研究者業績

岩田 仲生

イワタ ナカオ  (Nakao Iwata)

基本情報

所属
藤田医科大学 医学部 教授
学位
博士(医学)(名古屋大学)

J-GLOBAL ID
200901048638344557
researchmap会員ID
5000024641

外部リンク

1989年 名古屋大学医学部卒業
1993年 名古屋大学大学院修了 博士(医学)
1994年 名古屋大学医学部付属病院精神科 医員
1996年 National Institute of Health Visiting Fellow
1998年 藤田医科大学医学部精神神経科学 講師
2002年 藤田医科大学医学部精神神経科学 助教授
2003年 藤田医科大学医学部精神神経科学 教授(現職)
2011年 藤田医科大学研究支援推進本部 本部長(現職)
2015年 藤田医科大学医学部 医学部長(現職)
2016年 藤田医科大学 副学長(現職)
専門分野: 精神疾患の分子遺伝学、神経生化学、薬理遺伝学、臨床精神薬理学

学歴

 2

論文

 613
  • Taro Kishi, Kenji Sakuma, Makoto Okuya, Yuki Matsuda, Nakao Iwata
    Psychiatry and clinical neurosciences 74(5) 330-332 2020年5月  査読有り
  • Takeo Saito, Masashi Ikeda, Taisei Mushiroda, Nakao Iwata
    The Australian and New Zealand journal of psychiatry 54(5) 545-546 2020年5月  査読有り
  • Yui Murata, Tempei Ikegame, Shinsuke Koike, Takeo Saito, Masashi Ikeda, Tsukasa Sasaki, Nakao Iwata, Kiyoto Kasai, Miki Bundo, Kazuya Iwamoto
    Progress in neuro-psychopharmacology & biological psychiatry 99 109855-109855 2020年4月20日  査読有り
    Accumulating evidence suggests that aberrant epigenetic regulation is involved in the pathophysiology of major psychiatric disorders such as schizophrenia (SZ) and bipolar disorder (BD). We previously showed that the plasma level of betaine (N,N,N-trimethylglycine), a methyl-group donor, was significantly decreased in patients with first episode schizophrenia (FESZ). In this study, we identified decrease of global DNA methylation level in FESZ (N = 24 patients vs N = 42 controls), and found that global DNA methylation level was inversely correlated with scores on the global assessment of functioning (GAF) scale, and positively correlated with plasma betaine level. Notably, correlations between levels of betaine and its metabolites (N,N-dimethylglycine and sarcosine, N-methylglycine) were lower or lost in FESZ plasma, but remained high in controls. We further examined global DNA methylation levels in patients with chronic SZ (N = 388) and BD (N = 414) as well as controls (N = 430), and confirmed significant hypomethylation and decreased betaine level in SZ. We also found that patients with BD type I, but not those with BD type II, showed significant global hypomethylation. These results suggest that global hypomethylation associated with decreased betaine level in blood cells is common to SZ and BD, and may reflect common pathophysiology such as psychotic symptoms.
  • Taro Kishi, Kenji Sakuma, Nakao Iwata
    Pharmacopsychiatry 53(3) 109-114 2020年4月  
    INTRODUCTION: Several reports of the effectiveness of the use of psychostimulants for the treatment of Alzheimer's disease (AD) are available. METHODS: A systematic review and meta-analysis was conducted including double-blind, randomized, placebo-controlled trials. Outcomes were the improvement of apathy scales score (primary), mini-mental state examination (MMSE) score, activities of daily living scale score, Zarit burden interview score, all-cause discontinuation, discontinuation due to adverse events, and incidence of at least 1 adverse event. RESULTS: Three methylphenidate studies and 1 modafinil study were identified (n=156). Results from combined psychostimulants were superior to placebo in the improvement of apathy scales score (standardized mean differences [SMD]=-0.63 (-1.22, -0.04), p=0.04, all studies) and the MMSE score (SMD=-0.58 (-1.14, -0.02), p=0.04, 3 methylphenidate studies). The modafinil study was excluded from the meta-analysis for the improvement of apathy scales score; therefore, the effect size increased (SMD=-0.82 (-1.43, -0.20), p=0.009). However, no significant differences were observed in terms of other outcomes, including safety outcomes between the treatment groups. DISCUSSION: Methylphenidate would be effective in treating apathy and cognitive impairment in AD patients.
  • Ryoko Kawai, Akiko Watanabe, Shiho Fujita, Marina Hirose, Yuichi Esaki, Chiaki Arakawa, Nakao Iwata, Tsuyoshi Kitajima
    Sleep medicine 68 9-17 2020年4月  査読有り
    BACKGROUND: The minimum narcolepsy criteria "mean sleep latency (MSL) ≤8 min and ≥2 sleep onset rapid eye movement (REM) periods (SOREMPs) on polysomnography (PSG) and the multiple sleep latency test (MSLT)," according to The International Classification of Sleep Disorders, Third Edition (ICSD-3), are not specific to narcolepsy. Recently, the characteristic sleep stage sequences preceding SOREMPs in narcolepsy have received attention, but their diagnostic utility remains unclear. METHODS: We retrospectively reviewed PSG/MSLT records and chart data for 102 Japanese patients with hypersomnia and at least one SOREMP. We examined the sporadic rates of two sleep stage sequences preceding the SOREMPs-wakefulness or stage 1 to REM (W/S1→R) and stage 2 to REM (S2→R)-comparing these between patient groups with narcolepsy type 1 (N = 28), narcolepsy type 2 (N = 19), and other hypersomnia (N = 55). We also examined the utility of three simple indices using the occurrence of W/S1→R SOREMPs for distinguishing between narcolepsy and other hypersomnia in patients who satisfied the minimum narcolepsy criteria. RESULTS: W/S1→R SOREMPs were significantly more frequent in narcolepsy than in other hypersomnia, and this tendency was also observed even in the patients who satisfied the minimum narcolepsy criteria. The three indices had moderate sensitivities and specificities for distinguishing between narcolepsy and other hypersomnia in patients satisfying the minimum narcolepsy criteria. CONCLUSIONS: The W/S1→R pattern was observed significantly more frequently in narcolepsy than in other hypersomnia, suggesting it may help with differentiating narcolepsy from other hypersomnia in patients demonstrating the narcolepsy criteria, although its ability to do so may be modest.
  • Nana Matoba, Masato Akiyama, Kazuyoshi Ishigaki, Masahiro Kanai, Atsushi Takahashi, Yukihide Momozawa, Shiro Ikegawa, Masashi Ikeda, Nakao Iwata, Makoto Hirata, Koichi Matsuda, Yoshinori Murakami, Michiaki Kubo, Yoichiro Kamatani, Yukinori Okada
    Nature human behaviour 4(3) 308-316 2020年3月  
    Dietary habits are important factors in our lifestyle, and confer both susceptibility to and protection from a variety of human diseases. We performed genome-wide association studies for 13 dietary habits including consumption of alcohol (ever versus never drinkers and drinks per week), beverages (coffee, green tea and milk) and foods (yoghurt, cheese, natto, tofu, fish, small whole fish, vegetables and meat) in Japanese individuals (n = 58,610-165,084) collected by BioBank Japan, the nationwide hospital-based genome cohort. Significant associations were found in nine genetic loci (MCL1-ENSA, GCKR, AGR3-AHR, ADH1B, ALDH1B1, ALDH1A1, ALDH2, CYP1A2-CSK and ADORA2A-AS1) for 13 dietary traits (P < 3.8 × 10-9). Of these, ten associations between five loci and eight traits were new findings. Furthermore, a phenome-wide association study revealed that five of the dietary trait-associated loci have pleiotropic effects on multiple human complex diseases and clinical measurements. Our findings provide new insight into the genetics of habitual consumption.
  • Hiroyuki Kamei, Yuki Homma, Ippei Takeuchi, Genta Hajitsu, Kaori Tozawa, Masakazu Hatano, Aiko Fukui, Manako Hanya, Shigeki Yamada, Nakao Iwata
    Clinical psychopharmacology and neuroscience : the official scientific journal of the Korean College of Neuropsychopharmacology 18(1) 49-57 2020年2月29日  
    Objective: To improve poor medication adherence in schizophrenic patients, long-acting injectable (LAI) antipsychotics are used. However, it has not yet become common in Japan. Recently, aripiprazole LAI was approved for alternative injection into the deltoid muscle in addition to the gluteal muscle. The acceptance for the proposal to switch from gluteal to deltoid injections of aripiprazole LAI was investigated. Methods: The subjects were 32 outpatients with schizophrenia who had continuously received aripiprazole LAI administration into the gluteal muscle for ≥ 6 months. In the patients who had continued deltoid injection for 3 months after switching, the changes in the pain and shame in comparison with gluteal injections were evaluated. Results: Switching to the deltoid injection was chosen by 17 out of 32 patients. Three months later, 9 patients were still receiving deltoid injections with highly rated satisfaction. The main reasons for switching to deltoid injections included the pain and shame associated with gluteal injections. The main reason for returning to the gluteal injection was the pain experienced from the injection in the deltoid. Results: The option to select the injected area was based on the amount of pain in the deltoid and gluteal sites, leading to the widespread use of aripiprazole LAI.
  • Hiroyuki Kamei, Hanae Yamada, Masakazu Hatano, Manako Hanya, Shigeki Yamada, Nakao Iwata
    Clinical psychopharmacology and neuroscience : the official scientific journal of the Korean College of Neuropsychopharmacology 18(1) 159-163 2020年2月29日  
    In Japan, drug therapy for schizophrenia is characterized by high-dose antipsychotic polypharmacy, which is an uncommon approach internationally. In this study, we reduced the number of antipsychotic agents in 5 patients using the Safety Correction of High-dose Antipsychotic Polypharmacy (SCAP) method and conducted a survey regarding treatment satisfaction. The switch from polypharmacy to monotherapy was achieved in all patients. There was no deterioration in psychiatric symptoms, and adverse reactions were reduced. Three of the subjects were satisfied with the decrease in the number of antipsychotic agents and dose-reduction. These results suggest that the SCAP method is a safe and useful method that can be applied in a clinical setting.
  • Nakao Iwata, Jun Ishigooka, Won-Hyoung Kim, Bo-Hyun Yoon, Shih-Ku Lin, Ahmad Hatim Sulaiman, Rowena Cosca, Lina Wang, Yury Suchkov, Alexey Agarkov, Kei Watabe, Tomohito Matsui, Takayuki Sato, Yoshifumi Inoue, Teruhiko Higuchi, Christoph U Correll, John M Kane
    Schizophrenia research 215 408-415 2020年1月  
    BACKGROUND: Blonanserin is a second-generation antipsychotic used for the treatment of schizophrenia. This study determined the efficacy, safety and pharmacokinetics of a blonanserin transdermal patch in patients with acutely exacerbated schizophrenia. METHODS: This double-blind, multicenter, phase 3 study consisted of a 1-week observation period during which patients were treated with two patches of placebo, followed by a 6-week double-blind period where patients were randomized (1:1:1) to receive once-daily blonanserin 40 mg, blonanserin 80 mg, or placebo patches. The primary endpoint was the change from baseline in the total Positive and Negative Symptom Scale (PANSS) score. Safety assessments included treatment-emergent adverse events (TEAEs). RESULTS: Between December 2014 and October 2018, patients were recruited and randomly assigned to blonanserin 40 mg (n = 196), blonanserin 80 mg (n = 194), or placebo (n = 190); of these, 77.2% completed the study. Compared with placebo, blonanserin significantly improved PANSS total scores at 6 weeks (least square mean [LSM] difference vs placebo: -5.6 with blonanserin 40 mg; 95% confidence interval [CI] -9.6, -1.6; adjusted p = 0.007, and - 10.4 with blonanserin 80 mg; 95% CI -14.4, -6.4; adjusted p < 0.001). Blonanserin was well tolerated; the most common TEAEs reported were application-site erythema and pruritus, akathisia, tremor, and insomnia. CONCLUSIONS: Blonanserin transdermal patch improved the symptoms of acute schizophrenia with acceptable tolerability.
  • Nakao Iwata, Jun Ishigooka, Ichiro Naoi, Masahiro Matsumoto, Yuichi Kanamori, Hiroshi Nakamura, Teruhiko Higuchi
    CNS drugs 34(1) 103-116 2020年1月  
    BACKGROUND: Blonanserin transdermal patch therapy is now available in Japan for the treatment of schizophrenia and may provide several advantages over the tablet formulation. OBJECTIVE: The aim was to evaluate the long-term safety and efficacy of blonanserin transdermal patches in Japanese patients with schizophrenia. METHODS: An open-label study was conducted in adults with schizophrenia at 37 sites in Japan. Patients were enrolled in either cohort 1 or 2. Patients in cohort 1 received 8-16 mg/day blonanserin tablets for 6 weeks and then 40-80 mg/day blonanserin patches for 52 weeks. The dose of blonanserin patches was determined according to the dose of the tablets. In cohort 2, every patient started from 40 mg/day and then 40-80 mg/day blonanserin transdermal patches for 52 weeks. Both cohorts had 1-2 weeks of follow-up. Safety endpoints included the incidence of adverse events (AEs), treatment-related AEs, extrapyramidal AEs [also assessed using the change in Drug-Induced Extrapyramidal Symptoms Scale (DIEPSS) score], the use of any concomitant antiparkinsonian drugs, and skin-related AEs, including skin irritation. Patients also underwent assessment of laboratory values including for serum prolactin concentration, vital signs, body weight, electrocardiographic (ECG) changes, and the corrected QT (QTc) interval. Suicidal ideation was assessed via the Columbia-Suicide Severity Rating Scale (C-SSRS) score. Efficacy was assessed via duration of blonanserin transdermal patch treatment, Positive and Negative Syndrome Scale (PANSS) total and subscale scores, and Clinical Global Impression-Severity (CGI-S) scores. Other endpoints included total Drug Attitude Inventory 10 (DAI-10) scores, EuroQol-5 Dimension (EQ-5D) effect values, and a patient questionnaire about the dosage form. RESULTS: A total of 223 patients with consents, 117 in cohort 1 and 106 in cohort 2 were included in the study. Of the 117 patients in cohort 1, 108 were treated with blonanserin tablets, and 97 received blonanserin patches and were included in the safety analysis set. In cohort 2, 103 of the 106 patients were treated with blonanserin transdermal patches and were included in the safety analysis set. In total, 91 patients were male (45.5%). The mean age was 43.8 years. Discontinuation occurred in 40 patients (41.2%) in cohort 1 and 44 patients (42.7%) in cohort 2. Discontinuation resulted from AEs in 18.6% (cohort 1) and 11.7% (cohort 2) and from withdrawal of consent in 13.4% (cohort 1) and 20.4% (cohort 2), and seven patients overall discontinued due to skin reactions. AEs were reported in 174 patients (87.0%), and 13 serious AEs occurred in 12 patients (6.0%), of which six patients were in cohort 1 and six patients were in cohort 2. Serious AEs were six schizophrenia (n = 6) and seven other AEs (n = 6), which included impulse-control disorder, fracture, epistaxis, asthma, pneumonia aspiration, pneumonia hemophilus, and pneumonia. The most common AEs were nasopharyngitis (n = 62, 31.0%), application site erythema (n = 45, 22.5%), application site pruritus (n = 23, 11.5%), and akathisia (n = 20, 10.0%). AE incidence was similar in cohort 1 (84.5%) and cohort 2 (89.3%). Extrapyramidal and skin-related AEs were reported in 51 patients (25.5%) and 83 patients (41.5%), respectively. None of these AEs were serious. The mean change from baseline in total DIEPSS score at Week 52 {last observation carried forward [LOCF] (standard deviation [SD])} was -0.1 (1.55), indicating no marked effect. In terms of concomitant medications used in cohort 1 and cohort 2, 33.0% (32/97) and 22.3% (23/103) used antiparkinsonian drugs, respectively. The majority of skin-related AEs occurred early in treatment and were appropriately managed with topical therapies. Of the patients who answered "No" to all C-SSRS categories at baseline (n = 129), 13 patients (10.1%) were evaluated as having emergence of suicidal ideation. Among patients who answered "No" to all C-SSRS suicidal behavior categories at baseline (n = 172), one (0.6%) was evaluated as having suicidal behavior during blonanserin transdermal patch treatment. There were no clinically significant changes in laboratory tests or examinations, including prolactin level, vital signs, body weight, ECG, metabolism-related parameters, and QTc interval. The mean (SD) change in body weight was - 0.04 (4.561) kg and - 0.67 (6.841) kg in cohort 1 and cohort 2, respectively. The mean changes from baseline in PANSS total score at Week 52 (LOCF [SD]) were - 0.1 [11.6] and - 3.4 [15.3] in cohort 1 and 2, respectively. PANSS scores did not change after switching from tablet to patch formulation in cohort 1 and decreased over the 52 weeks of treatment with the blonanserin patches. The mean change from baseline in CGI-S score at Week 52 (LOCF [SD]) was - 0.2 [1.03] in both cohorts combined. After 52 weeks of blonanserin patch treatment, the total DAI-10 score increased or remained unchanged compared with baseline in 82 of the 129 patients (63.6%) for whom these data were available. In the intention-to-treat population of the combined cohorts (n = 200), the mean (SD) change from baseline in EQ-5D score at the last assessment was - 0.0365 (0.17603). Patients' attitudes to the blonanserin transdermal patches were generally positive. CONCLUSIONS: Blonanserin transdermal patches are safe and effective in the long-term treatment of schizophrenia. CLINICALTRIALS. GOV REGISTRATION: NCT02335658.
  • Kosei Esaki, Masashi Ikeda, Tomo Okochi, Satoru Taniguchi, Kohei Ninomiya, Ayu Shimasaki, Yasuyo Otsuka, Yoshiko Oda, Takaya Sakusabe, Keiko Mano, Takeo Saito, Nakao Iwata
    PloS one 15(10) e0240466 2020年  
    Depressive symptoms are a serious problem in workplaces. Hospital staff members, such as newly licensed registered nurses (NLRNs), are at particularly increased risk of these symptoms owing to their limited experience. Previous studies have shown that a brief program-based cognitive behavioral therapy program (CBP) can offer effective treatment. Here, we conducted a longitudinal observational study of 683 NLRNs (CBP group, n = 522; no-CBP group, n = 181) over a period of 1 year (six times surveys were done during this period). Outcomes were assessed on the basis of surveys that covered the Beck Depression Inventory-I (BDI). The independent variables were CBP attendance (CBP was conducted 3 months after starting work), personality traits, personal stressful life events, workplace adversity, and pre-CBP change in BDI in the 3 months before CBP (ΔBDIpre-CBP). All factors were included in Cox proportional hazards models with time-dependent covariates for depressive symptoms (BDI ≥10), and we reported hazard ratios (HRs). Based on this analysis, we detected that CBP was significantly associated with benefit for depressive symptoms in all NLRNs (Puncorrected = 0.0137, HR = 0.902). To identify who benefitted most from CBP, we conducted a subgroup analysis based on the change in BDI before CBP (ΔBDIpre-CBP). The strongest association was when BDI scores were low after starting work and increased before CBP (Puncorrected = 0.00627, HR = 0.616). These results are consistent with previous findings, and indicate that CBP may benefit the mental health of NLRNs. Furthermore, selective prevention based on the pattern of BDI change over time may be important in identifying who should be offered CBP first. Although CBP is generally effective for all nurses, such a selective approach may be most appropriate where cost-effectiveness is a prominent concern.
  • Naomichi Okamoto, Keita Watanabe, LeHoa Ngyuyen, Atsuko Ikenouchi, Taro Kishi, Nakao Iwata, Shingo Kakeda, Yukunori Korogi, Reiji Yoshimura
    Neuropsychiatric disease and treatment 16 2569-2577 2020年  
    Purpose: The kynurenine (KYN) pathway can directly or indirectly influence cerebral volume and neural integrity in patients with major depression (MD). The aim of the present study was to investigate neural network systems and the KYN pathway in patients with first-episode, drug-naïve MD. Patients and Methods: Twenty right-handed drug-naïve patients, with MD diagnosed using the Diagnostic and Statistical Manual for Mental Disorders, Fourth Edition, Text Revision, Research Version, were included in this study. Magnetic resonance imaging scans and scores on the Hamilton Rating Scale for Depression were assessed, and serum sampling was performed prior to the start of pharmacological treatment. Image processing and data analysis were performed according to our recently published procedure. Serum metabolomes were measured in the cation and anion modes of CE-FTMS-based metabolome analysis. Results: We found that serum KYN levels were positively correlated with the Z-scores of the salience network but not with those of the central executive network or default mode network. No associations were observed between serum glutamate levels and the Z-score of any of the three networks. Conclusion: Our results indicate that serum KYN levels might affect the activity of the salience network in first-episode, drug-naïve patients with MD.
  • Satoru Taniguchi, Kohei Ninomiya, Itaru Kushima, Takeo Saito, Ayu Shimasaki, Takaya Sakusabe, Yukihide Momozawa, Michiaki Kubo, Yoichiro Kamatani, Norio Ozaki, Masashi Ikeda, Nakao Iwata
    Psychiatry and clinical neurosciences 74(1) 35-39 2020年1月  査読有り
    AIMS: Recent studies have revealed that the interplay between polygenic risk scores (PRS) and large copy number variants (CNV; >500kb) is essential for the etiology of schizophrenia (SCZ). To replicate previous findings, including those for smaller CNV (>10kb), the PRS between SCZ patients with and without CNV were compared. METHODS: The PRS were calculated for 724 patients with SCZ and 1178 healthy controls (HC), genotyped using array-based comparative genomic hybridization and single nucleotide polymorphisms chips, and comparisons were made between cases and HC, or between subjects with and without 'clinically significant' CNV. RESULTS: First, we replicated the higher PRS in patients with SCZ compared to that in HC (without taking into account the CNV). For clinically significant CNV, as defined by the American College of Medical Genetics ('pathogenic' and 'uncertain clinical significance, likely pathogenic' CNV), 66 patients with SCZ carried clinically significant CNV, whereas 658 SCZ patients had no such CNV. In the comparison of PRS between cases with/without the CNV, despite no significant difference in PRS, significant enrichment of the well-established risk CNV (22q11.2 deletion and 47,XXY/47,XXX) was observed in the lowest decile of PRS in SCZ patients with the CNV. CONCLUSION: Although the present study failed to replicate the significant difference in PRS between SCZ patients with and without clinically significant CNV, SCZ patients with well-established risk CNV tended to have a lower PRS. Therefore, we speculate that the CNV in SCZ patients with lower PRS may contain 'genuine' risk; PRS is a possible tool for prioritizing clinically significant CNV because the power of the CNV association analysis is limited due to their rarity.
  • Kusui Yuka, Daisuke Nishizawa, Junko Hasegawa, Kyosuke Uno, Hajime Miyanishi, Hiroshi Ujike, Norio Ozaki, Toshiya Inada, Nakao Iwata, Ichiro Sora, Masaomi Iyo, Mitsuhiko Yamada, Naoki Kondo, Moo-Jun Won, Nobuya Naruse, Kumi Uehara-Aoyama, Kazutaka Ikeda, Atsumi Nitta
    Current pharmaceutical design 26(2) 260-264 2020年  査読有り
    BACKGROUND: Methamphetamine (METH) is one of the most widely distributed psychostimulants worldwide. Despite active counter measures taken by different countries, neither overall usage of METH nor the frequency of repeat users has reduced over the past decade. METH induces abuse and dependence as it acts on the central nervous system and temporarily stimulates the brain. The recidivism rate for abuse of stimulants in Japan is very high and therefore prevention of repeated usage is paramount. However, we lack information about the relationship between METH users and genomic changes in humans in Japan, which would provide important information to aid such efforts. OBJECTIVE: Shati/Nat8l is a METH-inducible molecule and its overexpression has protective effects on the brain upon METH usage. Here we investigated the effect of METH usage on DNA methylation rates at the promoter site of SHATI/NAT8L. We used DNA samples from human METH users, who are usually difficult to recruit in Japan. METHODS: We measured DNA methylation at SHATI/NAT8L promoter sites by pyrosequencing method using 193 samples of METH users and 60 samples of healthy subjects. In this method, DNA methylation is measured by utilizing the property that only non-methylated cytosine changes to urasil after bisulfite conversion. RESULTS: We found that the rate of DNA methylation at six CpG islands of SHATI/NAT8L promoter sites is significantly higher in METH users when compared to healthy subjects. CONCLUSION: These results suggest that the DNA methylation rate of SHATI/NAT8L promotor regions offers a new diagnostic method for METH usage.
  • Cell 179(7) 1469-1482 2019年12月12日  
    Genetic influences on psychiatric disorders transcend diagnostic boundaries, suggesting substantial pleiotropy of contributing loci. However, the nature and mechanisms of these pleiotropic effects remain unclear. We performed analyses of 232,964 cases and 494,162 controls from genome-wide studies of anorexia nervosa, attention-deficit/hyperactivity disorder, autism spectrum disorder, bipolar disorder, major depression, obsessive-compulsive disorder, schizophrenia, and Tourette syndrome. Genetic correlation analyses revealed a meaningful structure within the eight disorders, identifying three groups of inter-related disorders. Meta-analysis across these eight disorders detected 109 loci associated with at least two psychiatric disorders, including 23 loci with pleiotropic effects on four or more disorders and 11 loci with antagonistic effects on multiple disorders. The pleiotropic loci are located within genes that show heightened expression in the brain throughout the lifespan, beginning prenatally in the second trimester, and play prominent roles in neurodevelopmental processes. These findings have important implications for psychiatric nosology, drug development, and risk prediction.
  • Max Lam, Chia-Yen Chen, Zhiqiang Li, Alicia R Martin, Julien Bryois, Xixian Ma, Helena Gaspar, Masashi Ikeda, Beben Benyamin, Brielin C Brown, Ruize Liu, Wei Zhou, Lili Guan, Yoichiro Kamatani, Sung-Wan Kim, Michiaki Kubo, Agung A A A Kusumawardhani, Chih-Min Liu, Hong Ma, Sathish Periyasamy, Atsushi Takahashi, Zhida Xu, Hao Yu, Feng Zhu, Wei J Chen, Stephen Faraone, Stephen J Glatt, Lin He, Steven E Hyman, Hai-Gwo Hwu, Steven A McCarroll, Benjamin M Neale, Pamela Sklar, Dieter B Wildenauer, Xin Yu, Dai Zhang, Bryan J Mowry, Jimmy Lee, Peter Holmans, Shuhua Xu, Patrick F Sullivan, Stephan Ripke, Michael C O'Donovan, Mark J Daly, Shengying Qin, Pak Sham, Nakao Iwata, Kyung S Hong, Sibylle G Schwab, Weihua Yue, Ming Tsuang, Jianjun Liu, Xiancang Ma, René S Kahn, Yongyong Shi, Hailiang Huang
    Nature genetics 51(12) 1670-1678 2019年12月  
    Schizophrenia is a debilitating psychiatric disorder with approximately 1% lifetime risk globally. Large-scale schizophrenia genetic studies have reported primarily on European ancestry samples, potentially missing important biological insights. Here, we report the largest study to date of East Asian participants (22,778 schizophrenia cases and 35,362 controls), identifying 21 genome-wide-significant associations in 19 genetic loci. Common genetic variants that confer risk for schizophrenia have highly similar effects between East Asian and European ancestries (genetic correlation = 0.98 ± 0.03), indicating that the genetic basis of schizophrenia and its biology are broadly shared across populations. A fixed-effect meta-analysis including individuals from East Asian and European ancestries identified 208 significant associations in 176 genetic loci (53 novel). Trans-ancestry fine-mapping reduced the sets of candidate causal variants in 44 loci. Polygenic risk scores had reduced performance when transferred across ancestries, highlighting the importance of including sufficient samples of major ancestral groups to ensure their generalizability across populations.
  • Yuichi Esaki, Tsuyoshi Kitajima, Kenji Obayashi, Keigo Saeki, Kiyoshi Fujita, Nakao Iwata
    Journal of affective disorders 257(10) 314-320 2019年10月1日  査読有り
    BACKGROUND: Sleep disturbance in bipolar disorder (BD) is common and is associated with a risk for mood episode recurrence. Thus, it is important to identify factors that are related to sleep disturbance in BD. This cross-sectional study investigated the association between exposure to light at night (LAN) and sleep parameters in patients with BD. METHODS: The sleep parameters of 175 outpatients with BD were recorded using actigraphy at their homes for seven consecutive nights and were evaluated using the Insomnia Severity Index (ISI). The average LAN intensity in the bedroom during bedtime and rising time was measured using a portable photometer, and the participants were divided into two groups: "Light" (≥5 lx) and "Dark" (<5 lx). The association between LAN and sleep parameters was tested with multivariable analysis by adjusting for potential confounder such as age, gender, current smoker, mood state, day length, daytime light exposure, and sedative medications. RESULTS: After adjusting for potential confounder, the actigraphy sleep parameters showed significantly lower sleep efficiency (mean, 80.1%vs. 83.4%; p = 0.01), longer log-transformed sleep onset latency (2.9 vs. 2.6 min; p = 0.01), and greater wake after sleep onset (51.4 vs. 41.6 min; p = 0.02) in the Light group than in the Dark group. Whereas, there were no significant differences in the ISI scores between the groups. LIMITATIONS: This was a cross-sectional study; therefore, the results do not necessarily imply that LAN causes sleep disturbance. CONCLUSIONS: Reducing LAN exposure may contribute to improved sleep quality in patients with BD.
  • Nguyen L, Kakeda S, Katsuki A, Sugimoto K, Otsuka Y, Ueda I, Igata R, Watanabe K, Kishi T, Iwata N, Korogi Y, Yoshimura R
    European archives of psychiatry and clinical neuroscience 269(7) 785-794 2019年10月  査読有り
  • Jonathan L Hess, Daniel S Tylee, Manuel Mattheisen, Anders D Børglum, Thomas D Als, Jakob Grove, Thomas Werge, Preben Bo Mortensen, Ole Mors, Merete Nordentoft, David M Hougaard, Jonas Byberg-Grauholm, Marie Bækvad-Hansen, Tiffany A Greenwood, Ming T Tsuang, David Curtis, Stacy Steinberg, Engilbert Sigurdsson, Hreinn Stefánsson, Kári Stefánsson, Howard J Edenberg, Peter Holmans, Stephen V Faraone, Stephen J Glatt
    Molecular psychiatry 26(3) 800-815 2019年9月6日  
    Based on the discovery by the Resilience Project (Chen R. et al. Nat Biotechnol 34:531-538, 2016) of rare variants that confer resistance to Mendelian disease, and protective alleles for some complex diseases, we posited the existence of genetic variants that promote resilience to highly heritable polygenic disorders1,0 such as schizophrenia. Resilience has been traditionally viewed as a psychological construct, although our use of the term resilience refers to a different construct that directly relates to the Resilience Project, namely: heritable variation that promotes resistance to disease by reducing the penetrance of risk loci, wherein resilience and risk loci operate orthogonal to one another. In this study, we established a procedure to identify unaffected individuals with relatively high polygenic risk for schizophrenia, and contrasted them with risk-matched schizophrenia cases to generate the first known "polygenic resilience score" that represents the additive contributions to SZ resistance by variants that are distinct from risk loci. The resilience score was derived from data compiled by the Psychiatric Genomics Consortium, and replicated in three independent samples. This work establishes a generalizable framework for finding resilience variants for any complex, heritable disorder.
  • 土屋 晶子, 北島 剛司, 廣瀬 真里奈, 江崎 悠一, 河合 諒子, 荒川 千明, 熊谷 怜子, 山本 真太郎, 岩田 仲生
    心身医学 59(6) 573-573 2019年9月  
  • Kazuto Oya, Kenji Sakuma, Satoru Esumi, Yasuhiko Hashimoto, Masakazu Hatano, Yuki Matsuda, Yuki Matsui, Nobumi Miyake, Ikuo Nomura, Makoto Okuya, Nakao Iwata, Masaki Kato, Ryota Hashimoto, Kazuo Mishima, Norio Watanabe, Taro Kishi
    Neuropsychopharmacology reports 39(3) 241-246 2019年9月  査読有り
    AIM: Whether patients with adult bipolar disorder (BD) who have been clinically stabilized with lithium or lamotrigine should continue this medication is not established fully. This systematic review and meta-analysis evaluated the efficacy and safety of lithium and lamotrigine for maintenance treatment in clinically stable patients with adult BD. METHODS: This meta-analysis included only double-blind, randomized, placebo-controlled trials with an enrichment design that selected patients who responded acutely to lithium or lamotrigine. Reports prior to November 15, 2018, were retrieved from the PubMed/Cochrane Library/Embase. The primary outcome was the relapse rate due to any mood episode at the study endpoint. Other outcomes were relapse rates due to a manic/hypomanic/mixed episode or depression at the study endpoint, discontinuation rate, death, and death by suicide. Risk ratios (RRs) (95% confidence intervals) were calculated. When the random-effects model showed significant differences between groups, the number-needed-to-treat (NNT) was estimated. RESULTS: The search retrieved two studies regarding lithium (N = 218) and four evaluating lamotrigine (N = 706). Both drugs were superior to placebo for reducing the relapse rate due to any mood episode [lithium: RR = 0.52 (0.41-0.66), P < 0.00001, I2  = 0%, NNT = 2.3 (1.6-4.2); lamotrigine: RR = 0.81 (0.70-0.93), P = 0.004, I2  = 0%, NNT = 8.3 (5.0-25.0)] and all-cause discontinuation. There were no significant differences in other outcomes between lithium or lamotrigine and the placebo groups. CONCLUSION: Both drugs showed benefit for preventing relapse in clinically stable patients with adult BD. However, the number of studies and patients in this analysis was small.
  • Yuichi Esaki, Tsuyoshi Kitajima, Kenji Obayashi, Keigo Saeki, Kiyoshi Fujita, Nakao Iwata
    Journal of psychiatric research 116 151-156 2019年9月  査読有り
    OBJECTIVES: Controlled artificial daylight exposure, such as light therapy, is effective in bipolar depression, but the association between uncontrolled daytime light and depressive symptoms in bipolar disorder (BD) is unclear. This study investigated the association between daytime light exposure under real-life situations and depressive symptom in patients with BD. METHODS: This cross-sectional study enrolled 181 outpatients with BD. The average daytime light intensity and the total duration of light intensity of ≥1000 lux were recorded over 7 consecutive days using an actigraph that measured ambient light. Depressive symptoms were assessed using Montgomery-Åsberg Depression Rating Scale, and scores of ≥8 points were treated as depressed state. RESULTS: Ninety-seven (53.6%) subjects were depressed state. At higher average daytime light intensity tertiles, the proportion of depressed state was significantly lower (P for trend, 0.003). In multivariable analysis adjusted for age, employment status, age at onset of BD, Young Mania Rating Scale score, bedtime, and physical activity, the highest tertile group in average daytime light intensity suggested a significantly lower odds ratio (OR) for depressed state than the lowest tertile group (OR, 0.33; 95% confidence interval [CI], 0.14-0.75; P = 0.009). Similarly, the longest tertile group in light intensity ≥1000 lux duration was significantly associated with lower OR for depressed state than lowest tertile group (OR, 0.42; 95% CI, 0.18-0.93; P = 0.033). CONCLUSIONS: The findings suggest that greater daytime light exposure in daily life is associated with decreased depressive symptoms in BD.
  • Taro Kishi, Kenji Sakuma, Makoto Okuya, Kohei Ninomiya, Kazuto Oya, Momoko Kubo, Yuki Matsui, Ikuo Nomura, Yuji Okuyama, Shinji Matsunaga, Nakao Iwata
    Neuropsychopharmacology reports 39(3) 252-255 2019年9月  査読有り
    AIM: There have been no previous reports on the efficacy and safety of suvorexant for insomnia in people with psychiatric disorders. METHODS: This one-week, prospective, single-arm, clinical trial of fixed dose of suvorexant (20 mg if ages 18-64 or 15 mg if age ≥ 65 years) for insomnia included 57 patients with psychiatric disorders who had experienced any of the following insomnia symptoms for four or more nights during the week prior to the start of the study: total sleep time (TST) <6 hours, time to sleep onset (TSO) ≥30 minutes, or two or more episodes of wake after sleep onset. RESULTS: The mean age of the patients was 49.4 ± 17.3 years; 54.4% were women, 49.1% had a major depressive disorder, and 77.2% completed the trial. Compared with the baseline scores (the mean scores for the two days before the start of the study), taking suvorexant was associated with significant improvements in TST, TSO, wake time after sleep onset, and the patients' sleep satisfaction level at week 1. Adverse events included at least one adverse event (43.9%), sleepiness (28.8%), fatigue (11.5%), nightmares (5.8%), headache (3.8%), dizziness (3.8%), and vomiting (1.9%). CONCLUSION: Suvorexant was beneficial for the treatment of insomnia in people with psychiatric disorders. However, this study was of short duration and included only a relatively small number of patients. A larger, long-term study is needed to investigate the efficacy and safety of suvorexant for insomnia in people with psychiatric disorders.
  • Taro Kishi, Toshikazu Ikuta, Yuki Matsuda, Nakao Iwata
    Neuropsychopharmacology reports 39(3) 256-259 2019年9月  査読有り
    OBJECTIVE: It is unknown whether there are differences in efficacy and safety between quetiapine extended-release, 300 mg/d (QUEXR300), and olanzapine, 5-20 mg/d (OLA), for Japanese patients with bipolar depression. METHODS: We conducted a Bayesian analysis of data from phase 3 studies in Japan of QUEXR300 and OLA. Outcomes were remission rate (primary), response rate, improvement on the Montgomery-Åsberg Depression Rating Scale and 17-item Hamilton Depression Rating Scale scores, discontinuation rate, and incidence of individual adverse events. We calculated the standardized mean difference (SMD) and the risk ratio (RR) and 95% credible interval (95% CrI) for continuous and dichotomous data, respectively. RESULTS: There were no significant differences between QUEXR300 and OLA for any of the efficacy outcomes. QUEXR300 was associated with a higher incidence of somnolence than OLA (RR = 5.517; 95% CrI = 1.563, 19.787), while OLA was associated with greater increase body weight (SMD = -0.488; 95% CrI = -0.881, -0.089) and blood prolactin levels (SMD = -0.642; 95% CrI = -1.073, -0.213) than QUEXR300, and a greater decrease in high-density lipoprotein cholesterol levels (SMD = -0.408; 95% CrI = -0.785, -0.030) than QUEXR300. CONCLUSION: Although the two drugs' efficacy did not differ, OLA increased the risk of metabolic syndrome and QUEXR300 the risk of somnolence. A large scale, long-term, head-to-head comparison study of QUEXR300 vs OLA for Japanese patients with bipolar depression is needed to confirm the results of the current study.
  • Chenxing Liu, Tetsufumi Kanazawa, Ye Tian, Suriati Mohamed Saini, Serafino Mancuso, Md Shaki Mostaid, Atsushi Takahashi, Dai Zhang, Fuquan Zhang, Hao Yu, Hyoung Doo Shin, Hyun Sub Cheong, Masashi Ikeda, Michiaki Kubo, Nakao Iwata, Sung-Il Woo, Weihua Yue, Yoichiro Kamatani, Yongyong Shi, Zhiqiang Li, Ian Everall, Christos Pantelis, Chad Bousman
    Translational psychiatry 9(1) 205-205 2019年8月27日  査読有り
    Over 3000 candidate gene association studies have been performed to elucidate the genetic underpinnings of schizophrenia. However, a comprehensive evaluation of these studies' findings has not been undertaken since the decommissioning of the schizophrenia gene (SzGene) database in 2011. As such, we systematically identified and carried out random-effects meta-analyses for all polymorphisms with four or more independent studies in schizophrenia along with a series of expanded meta-analyses incorporating published and unpublished genome-wide association (GWA) study data. Based on 550 meta-analyses, 11 SNPs in eight linkage disequilibrium (LD) independent loci showed Bonferroni-significant associations with schizophrenia. Expanded meta-analyses identified an additional 10 SNPs, for a total of 21 Bonferroni-significant SNPs in 14 LD-independent loci. Three of these loci (MTHFR, DAOA, ARVCF) had never been implicated by a schizophrenia GWA study. In sum, the present study has provided a comprehensive summary of the current schizophrenia genetics knowledgebase and has made available all the collected data as a resource for the research community.
  • Taro Kishi, Toshikazu Ikuta, Kenji Sakuma, Yuki Matsuda, Nakao Iwata
    Journal of psychiatric research 115 121-128 2019年8月  査読有り
    This study evaluated the efficacy and safety/tolerability of quetiapine extended-release 300 mg/day (QUEXR300), quetiapine immediate-release 600 mg/day (QUEIR600), and quetiapine immediate-release 300 mg/day (QUEIR300) formulations for treating bipolar depression. A random-effect network meta-analysis of 8-week, double-blind, randomized placebo-controlled trials was used to determine the most optimal agent for intervention. Remission rate was set as the primary outcome. Secondary outcomes were response rate, improvement in the Montgomery-Åsberg Depression Rating Scale score, discontinuation rate, and the incidence of individual adverse events. Seven eligible studies including 3267 participants were included in the meta-analysis. The QUEIR600, QUEIR300, and QUEXR300 groups were superior to the placebo group in every efficacy outcome; however, there were no significant differences in the efficacy outcomes among the treatment groups. All treatment groups exhibited higher incidences of extrapyramidal symptoms, dry mouth, somnolence, constipation, and increase in body weight than the placebo group. The QUEIR600 and QUEIR300 groups had higher incidences of dizziness than the placebo group. The QUEIR600 group had a higher discontinuation rate due to adverse events than the placebo group, and the QUEIR300 group had higher blood HbA1c levels than the placebo group. The QUEIR600 and QUEXR300 groups had higher incidences of ≥7% weight gain than the placebo group. The QUEXR300 group had a higher incidence of fatigue than the QURIR300 and placebo groups. In conclusion, there were no significant differences in the efficacies of QUEIR600, QUEIR300, and QUEXR300 in treating bipolar depression; moreover, tolerance to QUEIR600 might be worse than the other treatments.
  • 池田 匡志, 金沢 徹文, 岩田 仲生
    臨床精神医学 48(7) 869-875 2019年7月  
  • Masashi Ikeda, Atsushi Takahashi, Yoichiro Kamatani, Yukihide Momozawa, Takeo Saito, Kenji Kondo, Ayu Shimasaki, Kohei Kawase, Takaya Sakusabe, Yoshimi Iwayama, Tomoko Toyota, Tomoyasu Wakuda, Mitsuru Kikuchi, Nobuhisa Kanahara, Hidenaga Yamamori, Yuka Yasuda, Yuichiro Watanabe, Satoshi Hoya, Branko Aleksic, Itaru Kushima, Heii Arai, Manabu Takaki, Kotaro Hattori, Hiroshi Kunugi, Yuko Okahisa, Tohru Ohnuma, Norio Ozaki, Toshiyuki Someya, Ryota Hashimoto, Takeo Yoshikawa, Michiaki Kubo, Nakao Iwata
    Schizophrenia bulletin 45(4) 824-834 2019年6月18日  査読有り
    Genome-wide association studies (GWASs) have identified >100 susceptibility loci for schizophrenia (SCZ) and demonstrated that SCZ is a polygenic disorder determined by numerous genetic variants but with small effect size. We conducted a GWAS in the Japanese (JPN) population (a) to detect novel SCZ-susceptibility genes and (b) to examine the shared genetic risk of SCZ across (East Asian [EAS] and European [EUR]) populations and/or that of trans-diseases (SCZ, bipolar disorder [BD], and major depressive disorder [MDD]) within EAS and between EAS and EUR (trans-diseases/populations). Among the discovery GWAS subjects (JPN-SCZ GWAS: 1940 SCZ cases and 7408 controls) and replication dataset (4071 SCZ cases and 54479 controls), both comprising JPN populations, 3 novel susceptibility loci for SCZ were identified: SPHKAP (Pbest = 4.1 × 10-10), SLC38A3 (Pbest = 5.7 × 10-10), and CABP1-ACADS (Pbest = 9.8 × 10-9). Subsequent meta-analysis between our samples and those of the Psychiatric GWAS Consortium (PGC; EUR samples) and another study detected 12 additional susceptibility loci. Polygenic risk score (PRS) prediction revealed a shared genetic risk of SCZ across populations (Pbest = 4.0 × 10-11) and between SCZ and BD in the JPN population (P ~ 10-40); however, a lower variance-explained was noted between JPN-SCZ GWAS and PGC-BD or MDD within/across populations. Genetic correlation analysis supported the PRS results; the genetic correlation between JPN-SCZ and PGC-SCZ was ρ = 0.58, whereas a similar/lower correlation was observed between the trans-diseases (JPN-SCZ vs JPN-BD/EAS-MDD, rg = 0.56/0.29) or trans-diseases/populations (JPN-SCZ vs PGC-BD/MDD, ρ = 0.38/0.12). In conclusion, (a) Fifteen novel loci are possible susceptibility genes for SCZ and (b) SCZ "risk" effect is shared with other psychiatric disorders even across populations.
  • Nana Matoba, Masato Akiyama, Kazuyoshi Ishigaki, Masahiro Kanai, Atsushi Takahashi, Yukihide Momozawa, Shiro Ikegawa, Masashi Ikeda, Nakao Iwata, Makoto Hirata, Koichi Matsuda, Michiaki Kubo, Yukinori Okada, Yoichiro Kamatani
    Nature human behaviour 3(5) 471-477 2019年5月  査読有り
    Cigarette smoking is a risk factor for a wide range of human diseases1. To investigate the genetic components associated with smoking behaviours in the Japanese population, we conducted a genome-wide association study of four smoking-related traits using up to 165,436 individuals. In total, we identified seven new loci, including three loci associated with the number of cigarettes per day (EPHX2-CLU, RET and CUX2-ALDH2), three loci associated with smoking initiation (DLC1, CXCL12-TMEM72-AS1 and GALR1-SALL3) and LINC01793-MIR4432HG, associated with the age of smoking initiation. Of these, three loci (LINC01793-MIR4432HG, CXCL12-TMEM72-AS1 and GALR1-SALL3) were found by conducting an additional sex-stratified genome-wide association study. This additional analysis showed heterogeneity of effects between sexes. The cross-sex linkage disequilibrium score regression2,3 analysis also indicated that the genetic component of smoking initiation was significantly different between the sexes. Cross-trait linkage disequilibrium score regression analysis and trait-relevant tissue analysis showed that the number of cigarettes per day has a specific genetic background distinct from those of the other three smoking behaviours. We also report 11 diseases that share genetic basis with smoking behaviours. Although the current study should be carefully considered owing to the lack of replication samples, our findings characterized the genetic architecture of smoking behaviours. Further studies in East Asian populations are warranted to confirm our findings.
  • Taro Kishi, Toshikazu Ikuta, Yuki Matsui, Ken Inada, Yuki Matsuda, Kazuo Mishima, Nakao Iwata
    Psychological medicine 49(5) 772-779 2019年4月  査読有り
    BACKGROUND: Discontinuation of antipsychotics predisposes patients with remitted/stable first-episode psychosis (FEP) to a higher risk of relapse, but it remains unclear how long discontinuation increases the relapse rate in these patients compared with maintenance. METHODS: This meta-analysis of randomized controlled trials (RCTs) compared relapse rates in FEP patients between antipsychotic treatment discontinuation and maintenance groups at 1, 2, 3, 6, 9, 12 (primary), and 18-24 months. The risk ratio (RR) and numbers needed to treat/harm (NNT/NNH) were calculated using a random-effects model. RESULTS: Ten RCTs were identified (n = 776; mean study duration, 18.6 ± 6.0 months). The antipsychotics were discontinued abruptly in four RCTs (which reported data only at 12 months) and after tapering off gradually over several months (mean length, 3 months) in six RCTs. Compared with the discontinuation group, the maintenance group experienced significantly fewer relapses at all time points except 1 month [RR (NNT): 2 months, 0.49 (13); 3 months, 0.46 (9); 6 months, 0.55 (6); 9 months, 0.48 (3); 12 months, 0.47 (3); and 18-24 months, 0.57 (4)]. The maintenance group was associated with higher discontinuation due to adverse events (RR, 2.61; NNH, not significant). CONCLUSIONS: Maintaining antipsychotic treatment prevented relapse for up to 24 months in FEP patients. Discontinuation of antipsychotics for ⩾2 months significantly increased the risk of relapse. However, 45.7% of patients who discontinued antipsychotics for 12 months (39.4% after 18-24 months) did not experience a relapse.
  • 鈴木 顕, 秋山 雅人, 石垣 和慶, 金井 仁弘, 細江 隼, 庄嶋 伸浩, 岩田 仲生, 池田 匡志, 池川 志郎, 前田 士郎, 村上 善則, 若井 建志, 津金 昌一郎, 佐々木 真理, 山本 雅之, 岡田 随象, 久保 充明, 鎌谷 洋一郎, 堀越 桃子, 山内 敏正, 門脇 孝
    糖尿病 62(Suppl.1) S-108 2019年4月  
  • Laura M Huckins, Amanda Dobbyn, Douglas M Ruderfer, Gabriel Hoffman, Weiqing Wang, Antonio F Pardiñas, Veera M Rajagopal, Thomas D Als, Hoang T Nguyen, Kiran Girdhar, James Boocock, Panos Roussos, Menachem Fromer, Robin Kramer, Enrico Domenici, Eric R Gamazon, Shaun Purcell, Ditte Demontis, Anders D Børglum, James T R Walters, Michael C O'Donovan, Patrick Sullivan, Michael J Owen, Bernie Devlin, Solveig K Sieberts, Nancy J Cox, Hae Kyung Im, Pamela Sklar, Eli A Stahl
    Nature genetics 51(4) 659-674 2019年4月  
    Transcriptomic imputation approaches combine eQTL reference panels with large-scale genotype data in order to test associations between disease and gene expression. These genic associations could elucidate signals in complex genome-wide association study (GWAS) loci and may disentangle the role of different tissues in disease development. We used the largest eQTL reference panel for the dorso-lateral prefrontal cortex (DLPFC) to create a set of gene expression predictors and demonstrate their utility. We applied DLPFC and 12 GTEx-brain predictors to 40,299 schizophrenia cases and 65,264 matched controls for a large transcriptomic imputation study of schizophrenia. We identified 413 genic associations across 13 brain regions. Stepwise conditioning identified 67 non-MHC genes, of which 14 did not fall within previous GWAS loci. We identified 36 significantly enriched pathways, including hexosaminidase-A deficiency, and multiple porphyric disorder pathways. We investigated developmental expression patterns among the 67 non-MHC genes and identified specific groups of pre- and postnatal expression.
  • Kenji Sakuma, Taro Kishi, Nakao Iwata
    Psychopharmacology 236(4) 1403-1404 2019年4月  査読有り
  • Ken Suzuki, Masato Akiyama, Kazuyoshi Ishigaki, Masahiro Kanai, Jun Hosoe, Nobuhiro Shojima, Atsushi Hozawa, Aya Kadota, Kiyonori Kuriki, Mariko Naito, Kozo Tanno, Yasushi Ishigaki, Makoto Hirata, Koichi Matsuda, Nakao Iwata, Masashi Ikeda, Norie Sawada, Taiki Yamaji, Motoki Iwasaki, Shiro Ikegawa, Shiro Maeda, Yoshinori Murakami, Kenji Wakai, Shoichiro Tsugane, Makoto Sasaki, Masayuki Yamamoto, Yukinori Okada, Michiaki Kubo, Yoichiro Kamatani, Momoko Horikoshi, Toshimasa Yamauchi, Takashi Kadowaki
    Nature genetics 51(3) 379-386 2019年3月  査読有り
    To understand the genetics of type 2 diabetes in people of Japanese ancestry, we conducted A meta-analysis of four genome-wide association studies (GWAS; 36,614 cases and 155,150 controls of Japanese ancestry). We identified 88 type 2 diabetes-associated loci (P < 5.0 × 10-8) with 115 independent signals (P < 5.0 × 10-6), of which 28 loci with 30 signals were novel. Twenty-eight missense variants were in linkage disequilibrium (r2 > 0.6) with the lead variants. Among the 28 missense variants, three previously unreported variants had distinct minor allele frequency (MAF) spectra between people of Japanese and European ancestry (MAFJPN > 0.05 versus MAFEUR < 0.01), including missense variants in genes related to pancreatic acinar cells (GP2) and insulin secretion (GLP1R). Transethnic comparisons of the molecular pathways identified from the GWAS results highlight both ethnically shared and heterogeneous effects of a series of pathways on type 2 diabetes (for example, monogenic diabetes and beta cells).
  • Taro Kishi, Yuki Matsui, Yuki Matsuda, Asuka Katsuki, Hikaru Hori, Hiroko Yanagimoto, Kenji Sanada, Kiichiro Morita, Reiji Yoshimura, Yoshihisa Shoji, Katsuhiko Hagi, Nakao Iwata
    Pharmacopsychiatry 52(2) 52-62 2019年2月  査読有り
    INTRODUCTION: We conducted an updated systematic review and meta-analysis of randomized controlled trials (RCTs) comparing blonanserin with other antipsychotics (amisulpride, aripiprazole, haloperidol, paliperidone, and risperidone). METHODS: Weighted mean difference (WMD), risk ratio, and number needed to harm (NNH) with 95% confidence intervals (95% CIs) were calculated using random-effects model. RESULTS: Ten RCTs (n=1521) were included in this study. Blonanserin was superior to aripiprazole in improvement of Positive and Negative Syndrome Scale total scores (WMD=-10.62, 95% CI=-17.67 to -3.560, p=0.003). Blonanserin was associated with a higher incidence of all-cause discontinuation (RR=1.373, 95% CI=1.088-1.734, p=0.008, NNH=11), akathisia, extrapyramidal disorder, and agitation/excitement and a lower risk of hyperprolactinemia compared with risperidone + paliperidone. DISCUSSION: The current meta-analytic study did not update the comparison of blonanserin vs. haloperidol because there were no new RCTs. Our results suggest that the efficacy of blonanserin for schizophrenia is comparable with that of other antipsychotics, and blonanserin seems to be well tolerated.
  • Hisatsugu Koshimizu, Shun Nogawa, Shinya Asano, Masashi Ikeda, Nakao Iwata, Shoko Takahashi, Kenji Saito, Tsuyoshi Miyakawa
    Translational psychiatry 9(1) 52-52 2019年1月31日  査読有り
    Major depressive disorder (MDD) is a common and disabling psychiatric disorder. A recent mega analysis of genome-wide association studies (GWASs) identified 44 loci associated with MDD, though most of the genetic etiologies of the MDD/psychological distress remain unclear. To further understand the genetic basis of MDD/psychological distress, we conducted a GWAS in East Asia with more than 10,000 participants of Japanese ancestry who had enrolled in a direct-to-consumer genetic test. After quality control on the genotype data, 10,330 subjects with a total of 8,567,708 imputed SNPs were eligible for the analysis. The participants completed a self-administered questionnaire on their past medical history and health conditions that included the 6-item Kessler screening scale (K6 scale) for psychological distress (cut-off point of 5) and past medical history of MDD, resulting in 3981 subjects assigned to "psychologically distressed group" [cases], and the remaining 6349 subjects were assigned to the "non-psychologically distressed group" [controls]. In this GWAS, we found an association with genome-wide significance at rs6073833 (P = 7.60 × 10-9) in 20q13.12. This is, to the best of our knowledge, the first large-scale GWAS for psychological distress using data from direct-to-consumer (DTC) genetic tests in a population of non-European-ancestry, and the present study thus detected a novel locus significantly associated with psychological distress in the Japanese population.
  • Reiji Yoshimura, Taro Kishi, Nakao Iwata
    Neuropsychiatric disease and treatment 15 2655-2661 2019年  
    Objective: IL-6 and catecholamines play roles in the pathophysiology of major depressive disorder (MDD). Aim: The present study investigated associations between plasma IL-6 and plasma catecholamine metabolites in patients with MDD. Participants and methods: A total of 148 patients (male/female 65/83, age 49.5±12.1 years) who met the criteria for MDD based on the Diagnostic and Statistical Manual of Mental Disorders IV and 40 participants as healthy controls (HC; male/female 23/17, age 44.0±10.5 years) were enrolled in the present study. Plasma levels of 3-methoxy-4-hydroxyphenylglycol (MHPG) and homovanillic acid (HVA) were analyzed using high-performance liquid chromatography, and plasma IL-6 levels were measured using ELISA. Results: No correlations were observed among plasma IL-6 levels, MHPG levels, and HVA levels in patients with MDD. Plasma IL-6 levels in patients with MDD were significantly higher than in the HC. A positive correlation was found between plasma IL-6 levels and Hamilton Rating Scale for Depression-17 scores. Conclusion: No correlations existed between plasma IL-6 levels and plasma catecholamine metabolite levels in patients with MDD, and the severity of depressive state was related to plasma IL-6 levels in MDD.
  • Hirofumi Igeta, Yuichiro Watanabe, Ryo Morikawa, Masashi Ikeda, Ikuo Otsuka, Satoshi Hoya, Masataka Koizumi, Jun Egawa, Akitoyo Hishimoto, Nakao Iwata, Toshiyuki Someya
    Neuropsychiatric disease and treatment 15 2353-2363 2019年  査読有り
    Purpose: Whole-exome sequencing (WES) of multiplex families is a promising strategy for identifying causative variations for common diseases. To identify rare recessive risk variations for schizophrenia, we performed a WES study in a consanguineous family with affected siblings. We then performed follow-up sequencing of SPATA7 in schizophrenia-affected families. In addition, we performed a case-control study to investigate association between SPATA7 variations and schizophrenia. Patients and methods: WES was performed on two affected siblings and their unaffected parents, who were second cousins, of a multiplex schizophrenia family. Subsequently, we sequenced the coding region of SPATA7, a potential risk gene identified by the WES analysis, in 142 affected offspring from 137 families for whom parental DNA samples were available. We further tested rare recessive SPATA7 variations, identified by WES and sequencing, for associations with schizophrenia in 2,756 patients and 2,646 controls. Results: Our WES analysis identified rare compound heterozygous missense SPATA7 variations, p.Asp134Gly and p.Ile332Thr, in both affected siblings. Sequencing SPATA7 coding regions from 137 families identified no rare recessive variations in affected offspring. In the case-control study, we did not detect the rare compound heterozygous SPATA7 missense variations in patients or controls. Conclusion: Our data does not support the role of the rare compound heterozygous SPATA7 missense variations p.Asp134Gly and p.Ile332Thr in conferring a substantial risk of schizophrenia.
  • Masakazu Hatano, Hiroyuki Kamei, Ippei Takeuchi, Kaori Tozawa, Shinya Makino, Manako Hanya, Shigeki Yamada, Nakao Iwata
    Human psychopharmacology 34(1) e2681 2019年1月  査読有り
    OBJECTIVE: Long-acting injectable (LAI) aripiprazole is recommended to be combined with oral aripiprazole for 2 weeks after its introduction. However, we often experience patients who require more than 2 weeks of combined use. Therefore, differences in combination periods need to be examined. METHODS: This was a case-control study. We surveyed prescription profiles for oral aripiprazole administration in conjunction with LAI aripiprazole introduction and assessed the clinical course during a 12-week follow-up period. RESULTS: Among 121 patients, 58 (47.9%) were administered both oral and LAI aripiprazole for more than 2 weeks. Although there was no significant difference in treatment failure (defined as psychiatric hospitalization or discontinuation of LAI aripiprazole from any cause) between the two groups, the group that was administered oral aripiprazole for more than 2 weeks received less additional benzodiazepines compared with that of the 2 weeks group (adjusted odds ratio, 0.055; 95% confidence interval [0.0060, 0.50]; p < 0.01). CONCLUSIONS: Our data support a flexible co-administration period for oral and LAI aripiprazole in consideration of the pharmacokinetics, but further studies are needed.
  • Shingo Kakeda, Keita Watanabe, Asuka Katsuki, Koichiro Sugimoto, Issei Ueda, Natsuki Igata, Taro Kishi, Nakao Iwata, Osamu Abe, Reiji Yoshimura, Yukunori Korogi
    Neuropsychiatric disease and treatment 15 375-383 2019年  査読有り
    Background: A genome-wide association study using megadata identified 17 single-nucleotide polymorphisms (SNPs) in candidate genes for major depressive disorder (MDD). These MDD susceptibility polymorphisms may affect white matter (WM) integrity. This study aimed to investigate the relationship between WM alterations and 17 SNPs in candidate genes for MDD in the first depressive episode of drug-naive MDD patients using a tract-based spatial statistics (TBSS) method. Methods: Thirty-five drug-naive MDD patients with a first depressive episode and 47 age-and sex-matched healthy subjects underwent diffusion tensor imaging scans and genotyping. The genotype-diagnosis interactions related to WM integrity were evaluated using TBSS for the 17 SNPs. Results: For the anterior thalamic radiation, cingulum, corticospinal tract, inferior fronto-occipital fasciculus, inferior longitudinal fasciculus, superior longitudinal fasciculus, uncinate fasciculus, forceps major, and forceps minor, the genotype effect significantly differed between diagnosis groups (P<0.05, family-wise error corrected) in only one SNP, rs301806, in the arginine-glutamic acid dipeptide (RE) repeats (RERE) gene. Conclusion: The RERE polymorphism was associated with WM alterations in first-episode and drug-naive MDD patients, which may be at least partially related to the manifestation of MDD. Future studies are needed to explore the gene-environment interactions with regard to individual WM integrity.
  • Taro Kishi, Ikuo Nomura, Kenji Sakuma, Tsuyoshi Kitajima, Kazuo Mishima, Nakao Iwata
    Neuropsychiatric disease and treatment 15 1479-1486 2019年  査読有り
    Objective: This study was a systematic review and meta-analysis of double-blind, randomized, placebo-controlled trials, investigating the efficacy and tolerability/safety of melatonin receptor agonists, such as ramelteon and melatonin, for patients with bipolar disorder. Methods: We carried out a literature search through PubMed and the Cochrane Library from the date of inception to January 6, 2019. The risk ratio (RR), number needed to treat (NNT), and standardized mean difference (SMD) ±95% CI were calculated. The primary outcome was all-cause discontinuation. Results: We identified three ramelteon (n=746) and two melatonin (n=53) studies. One of these two melatonin studies reported only data on all-cause discontinuation, whereas the other study did not report data relevant for a meta-analysis. We found no significant differences between the treatment and placebo groups regarding all-cause discontinuation, neither individually (p: ramelteon=0.86, melatonin=1.00) nor pooled together (p=0.85). Although we found no significant differences between ramelteon and placebo regarding the relapse due to mania/hypomania or mixed episode; Pittsburgh Sleep Quality Index scores; depression scales scores; Quality of Life Enjoyment and Satisfaction Questionnaire - Short Form scores; and the incidence of individual adverse events, such as headaches, insomnia, somnolence, anxiety, and dizziness, ramelteon was associated with a lower incidence of relapse due to depression than placebo (RR=0.67, 95% CI=0.48-0.94, p=0.02, NNT=14). Conclusion: Ramelteon might prevent relapse due to depression in patients with bipolar disorder. However, because of the small number of studies included in the present systematic review and meta-analysis, further studies comparing ramelteon and placebo with larger samples of patients with bipolar disorder are warranted. We also did not evaluate the efficacy and safety of melatonin for patients with bipolar disorder in detail.
  • Yuka Otsuka, Shingo Kakeda, Koichiro Sugimoto, Asuka Katsuki, Le Hoa Nguyen, Ryohei Igata, Keita Watanabe, Issei Ueda, Taro Kishi, Nakao Iwata, Yukunori Korogi, Reiji Yoshimura
    Neuropsychiatric disease and treatment 15 1537-1545 2019年  査読有り
    Purpose: Compared with healthy subjects (HS), patients with major depressive disorder (MDD) exhibit volume differences that affect the volume changes in several areas such as the limbic, cortical, subcortical, and white matter. Catechol-O-methyltransferase (COMT) is a methylation enzyme that catalyzes endogenous catecholamines. The Val158Met polymorphism of COMT has been reported to affect the dopamine (DA) levels, which plays an important role in psychiatric diseases. However, the relationships among both DA levels, COMT genotype, and brain morphology are complicated and controversial. In previous studies that investigated the hippocampal subfields, the greatest brain abnormalities in MDD patients were observed in Cornu Ammonis (CA)1 and the subiculum, followed by that in CA2-3. We have prospectively demonstrated the relationship between the single-nucleotide polymorphism of the Val158Met COMT gene (rs4680) and the hippocampal subfields in drug-naive MDD patients. Patients and methods: In this study, we compared 27 MDD patients and 42 HS who were divided into groups based on their COMT genotype. The effects of the diagnosis, genotype, and genotype-diagnosis interaction related to CA1 and the subiculum volumes, as well as the whole-brain cortical thickness, were evaluated by performing a FreeSurfer statistical analysis of high-resolution magnetic resonance imaging (MRI) findings. Results: The results revealed that there was a statistically significant interaction between the effects of diagnosis and genotype on the right subiculum (a component of the hippocampus). Conclusion: This Val158Met COMT polymorphism may influence the subiculum volume in drug-naive, first-episode MDD patients.
  • Kanako Ishizuka, Hiroki Kimura, Itaru Kushima, Toshiya Inada, Yuko Okahisa, Masashi Ikeda, Nakao Iwata, Daisuke Mori, Branko Aleksic, Norio Ozaki
    Psychiatric genetics 28(5) 90-93 2018年10月  査読有り
    Enhanced carbonyl stress has been observed in a subgroup of patients with schizophrenia. Glyoxalase I, which is encoded by GLO1, is an enzyme that protects against carbonyl stress. In this study, we focused on the association between rare genetic variants of GLO1 and schizophrenia. First, we identified one heterozygous frameshift variant, p.P122fs, in 370 Japanese schizophrenia cases with allele frequencies of up to 1% by exon-targeted mutation screening of GLO1. We then performed an association analysis on 1282 cases and 1764 controls with this variant. The variant was found in three cases and eight controls. There was no statistically significant association between p.P122fs in GLO1 and schizophrenia (P=0.25). This frameshift variant in GLO1 might occur at near-polymorphic frequencies in the Japanese population, although further investigations using larger samples and biological analyses are needed to exclude the possibility of a low-penetrance genetic risk associated with this variant.
  • Shinji Matsunaga, Taro Kishi, Ikuo Nomura, Kenji Sakuma, Makoto Okuya, Toshikazu Ikuta, Nakao Iwata
    Expert opinion on drug safety 17(10) 1053-1061 2018年10月  査読有り
    INTRODUCTION: Currently, five pharmacotherapeutic options are available to treat Alzheimer's disease: memantine; the three cholinesterase inhibitors donepezil, galantamine, and rivastigmine; and combination treatments with memantine and one cholinesterase inhibitor. Selection of the best course of treatment is based upon the evidence gathered by systematic reviews and meta-analyses of randomized controlled trials. Areas covered: This article provides a risk-benefit analysis of these treatments using evidence from meta-analyses on their safety and their efficacy. Expert opinion: Memantine improves cognitive functions and behavioral disturbances more efficiently than the placebo, both as monotherapy and in combination with donepezil. Although memantine monotherapy and combination therapy are associated with a few individual adverse events such as somnolence, it is well-tolerated and its safety (all-cause discontinuation) is comparable or superior to that of the placebo (agitation). Pooled cholinesterase inhibitors are superior to the placebo in the improvement of cognitive functions, but not behavioral disturbances and they are not well-tolerated, as evaluated by the high discontinuation rate. Donepezil (10 mg/day) and oral rivastigmine and galantamine monotherapies carry the risk for some adverse events including gastrointestinal symptoms. Therefore, we consider that combined treatment with memantine and donepezil is the most useful treatment for Alzheimer's disease.
  • Itaru Kushima, Branko Aleksic, Masahiro Nakatochi, Teppei Shimamura, Takashi Okada, Yota Uno, Mako Morikawa, Kanako Ishizuka, Tomoko Shiino, Hiroki Kimura, Yuko Arioka, Akira Yoshimi, Yuto Takasaki, Yanjie Yu, Yukako Nakamura, Maeri Yamamoto, Tetsuya Iidaka, Shuji Iritani, Toshiya Inada, Nanayo Ogawa, Emiko Shishido, Youta Torii, Naoko Kawano, Yutaka Omura, Toru Yoshikawa, Tokio Uchiyama, Toshimichi Yamamoto, Masashi Ikeda, Ryota Hashimoto, Hidenaga Yamamori, Yuka Yasuda, Toshiyuki Someya, Yuichiro Watanabe, Jun Egawa, Ayako Nunokawa, Masanari Itokawa, Makoto Arai, Mitsuhiro Miyashita, Akiko Kobori, Michio Suzuki, Tsutomu Takahashi, Masahide Usami, Masaki Kodaira, Kyota Watanabe, Tsukasa Sasaki, Hitoshi Kuwabara, Mamoru Tochigi, Fumichika Nishimura, Hidenori Yamasue, Yosuke Eriguchi, Seico Benner, Masaki Kojima, Walid Yassin, Toshio Munesue, Shigeru Yokoyama, Ryo Kimura, Yasuko Funabiki, Hirotaka Kosaka, Makoto Ishitobi, Tetsuro Ohmori, Shusuke Numata, Takeo Yoshikawa, Tomoko Toyota, Kazuhiro Yamakawa, Toshimitsu Suzuki, Yushi Inoue, Kentaro Nakaoka, Yu-Ichi Goto, Masumi Inagaki, Naoki Hashimoto, Ichiro Kusumi, Shuraku Son, Toshiya Murai, Tempei Ikegame, Naohiro Okada, Kiyoto Kasai, Shohko Kunimoto, Daisuke Mori, Nakao Iwata, Norio Ozaki
    Cell reports 24(11) 2838-2856 2018年9月11日  査読有り
    Compelling evidence in Caucasian populations suggests a role for copy-number variations (CNVs) in autism spectrum disorder (ASD) and schizophrenia (SCZ). We analyzed 1,108 ASD cases, 2,458 SCZ cases, and 2,095 controls in a Japanese population and confirmed an increased burden of rare exonic CNVs in both disorders. Clinically significant (or pathogenic) CNVs, including those at 29 loci common to both disorders, were found in about 8% of ASD and SCZ cases, which was significantly higher than in controls. Phenotypic analysis revealed an association between clinically significant CNVs and intellectual disability. Gene set analysis showed significant overlap of biological pathways in both disorders including oxidative stress response, lipid metabolism/modification, and genomic integrity. Finally, based on bioinformatics analysis, we identified multiple disease-relevant genes in eight well-known ASD/SCZ-associated CNV loci (e.g., 22q11.2, 3q29). Our findings suggest an etiological overlap of ASD and SCZ and provide biological insights into these disorders.
  • Taro Kishi, Toshikazu Ikuta, Kazuto Oya, Shinji Matsunaga, Yuki Matsuda, Nakao Iwata
    The international journal of neuropsychopharmacology 21(8) 748-757 2018年8月1日  査読有り
    BACKGROUND: We conducted a systematic review and meta-analysis of double-blind, randomized, placebo-controlled trials of anti-dementia drugs plus antipsychotics for schizophrenia. METHODS: Primary outcomes of efficacy and safety included improving overall symptoms (Positive and Negative Syndrome Scale and Brief Psychiatric Rating Scale scores) and all-cause discontinuation, respectively. Other outcomes included psychopathology subscales (positive, negative, general, and anxiety/depressive symptoms), cognitive function (attention/vigilance, reasoning/problem solving, social cognition, speed of processing, verbal learning, visual learning, working memory, and cognitive control/executive function), Mini-Mental State Examination scores, treatment discontinuation due to adverse events and inefficacy, and individual adverse events. We evaluated the effect size using a random effects model. RESULTS: We identified 37 studies (n=1574): 14 donepezil-based (n=568), 10 galantamine-based (n=371), 4 rivastigmine-based (n=146), and 9 memantine-based (n=489) studies. Pooled anti-dementia drugs plus antipsychotics treatments were superior to placebo plus antipsychotics in improving the overall symptoms (24 studies, 1069 patients: standardized mean difference=-0.34, 95% CI=-0.61 to -0.08, P=.01), negative symptoms (24 studies, 1077 patients: standardized mean difference =-0.62, 95% CI=-0.92 to -0.32, Pcorrected=.00018), and Mini-Mental State Examination scores (7 studies, 225 patients: standardized mean difference=-0.79, 95% CI=-1.23 to -0.34, P=.0006). No significant differences were found between anti-dementia drugs plus antipsychotics and placebo plus antipsychotics regarding other outcomes. CONCLUSIONS: Although the results suggest that anti-dementia drugs plus antipsychotics treatment improves negative symptoms and Mini-Mental State Examination scores in schizophrenia patients, they possibly were influenced by a small-study effect and some bias. However, it was not superior to placebo plus antipsychotics in improving composite cognitive test score, which more systematically evaluates cognitive impairment than the Mini-Mental State Examination score. Overall, the anti-dementia drugs plus antipsychotics treatment was well tolerated.
  • Kenji Sakuma, Shinji Matsunaga, Ikuo Nomura, Makoto Okuya, Taro Kishi, Nakao Iwata
    Psychopharmacology 235(8) 2303-2314 2018年8月  査読有り
    RATIONALE: This study aims to examine whether folate/folic acid/methylfolate/folinic acid supplemented to antipsychotics (FA + AP) is beneficial in schizophrenia treatment. OBJECTIVE: We conducted a comprehensive systematic review and meta-analysis of double-blind, placebo-controlled, randomized clinical trials (RCTs) of FA + AP for schizophrenia. METHODS: The primary outcome was an improvement in total symptoms. Other outcomes were psychopathology subscales (positive, negative, general, and depressive symptoms), discontinuation due to all-cause and adverse events, and individual adverse events. The meta-analysis evaluated the effect size based on a random-effects model. RESULTS: Although we included ten RCTs with 925 patients in total (seven folic acid RCTs (n = 789), two methylfolate RCTs (n = 96), and one folinic acid RCT (n = 40)) in the systematic review, only seven RCTs were included in the meta-analysis. Pooled FA + AP treatments were not superior to placebo + AP in the improvement of total (N = 7, n = 340; standardized mean difference (SMD) = - 0.20, 95% confidence interval (CI) = - 0.41, 0.02, p = 0.08, I2 = 0%), positive, general, or depressive symptoms. Pooled FA + AP treatments were more effective than placebo + AP for negative symptoms (N = 5, n = 281; SMD = -0.25, 95% CI = -0.49, -0.01, p = 0.04, I2 = 0%). Although pooled FA + AP treatments were associated with a lower incidence of serious adverse events than placebo treatments (N = 4, n = 241; risk ratio = 0.32, 95% CI = 0.12-0.82, p = 0.02, I2 = 0%; number needed to harm = not significant), there were no significant differences in other safety outcomes between both treatments. CONCLUSIONS: Our findings suggest that pooled FA + AP treatment improves negative symptoms in schizophrenia patients. Moreover, this treatment was well tolerated. However, because our results might exhibit a small-study effect, future studies with a larger sample should be conducted to obtain more robust results.
  • Hirose M, Arakawa C, Watanabe A, Esaki Y, Kawai R, Iwata N, Kitajima T
    Fujita Medical Journal 4(3) 70-76 2018年8月  査読有り
  • Akiko Watanabe, Marina Hirose, Chiaki Arakawa, Nakao Iwata, Tsuyoshi Kitajima
    Journal of clinical sleep medicine : JCSM : official publication of the American Academy of Sleep Medicine 14(7) 1265-1267 2018年7月15日  査読有り
    ABSTRACT: Non-24-hour sleep-wake rhythm disorder (N24SWD) occurs when the intrinsic circadian pacemaker does not entrain (synchronize) to the 24-hour light/dark cycle. There is currently no established treatment for sighted patients with N24SWD. To the best of our knowledge, there have been very few reports on the efficacy of ramelteon administered to sighted patients with N24SWD. We report the case of a sighted patient with N24SWD whose free-running sleep-wake pattern recorded by actigraphy was stopped after the administration of a low dose of ramelteon combined with behavioral education.
  • Guiyan Ni, Jacob Gratten, Naomi R Wray, Sang Hong Lee
    Scientific reports 8(1) 10168-10168 2018年7月5日  
    Previous studies have shown an increased risk for mental health problems in children born to both younger and older parents compared to children of average-aged parents. We previously used a novel design to reveal a latent mechanism of genetic association between schizophrenia and age at first birth in women (AFB). Here, we use independent data from the UK Biobank (N = 38,892) to replicate the finding of an association between predicted genetic risk of schizophrenia and AFB in women, and to estimate the genetic correlation between schizophrenia and AFB in women stratified into younger and older groups. We find evidence for an association between predicted genetic risk of schizophrenia and AFB in women (P-value = 1.12E-05), and we show genetic heterogeneity between younger and older AFB groups (P-value = 3.45E-03). The genetic correlation between schizophrenia and AFB in the younger AFB group is -0.16 (SE = 0.04) while that between schizophrenia and AFB in the older AFB group is 0.14 (SE = 0.08). Our results suggest that early, and perhaps also late, age at first birth in women is associated with increased genetic risk for schizophrenia in the UK Biobank sample. These findings contribute new insights into factors contributing to the complex bio-social risk architecture underpinning the association between parental age and offspring mental health.

MISC

 625

書籍等出版物

 6

共同研究・競争的資金等の研究課題

 15