江崎 悠一

STUDY OBJECTIVES: Light information crucially influences the sleep initiation and continuity. The purpose of this study was to compare daily light exposure between patients with Parkinson's disease (PD) and non-PD older adults and evaluate the association of daily light exposure with objective sleep measures in patients with PD. METHODS: In this cross-sectional study of 189 outpatients with PD and 1101 community dwelling older adults (controls), daily light exposure was measured using wrist light meters during the daytime and light meters set in the bedrooms during the nighttime, and objective sleep quality was measured by wrist actigraphy. RESULTS: The median duration of exposure to ≥1000 lux light was significantly shorter in patients with PD than in controls. The median nighttime light intensity was higher in patients with PD than in controls. Among patients with PD, multivariable analysis suggested that the highest quartile of exposure to ≥1000 lux light during the daytime was linked to significantly higher sleep efficiency by 8.0% and shorter wake after sleep onset (WASO) by 36.9 min than the lowest quartile. During the nighttime, the highest quartile of mean light intensity had significantly lower sleep efficiency by 6.8%, longer WASO by 24.1 min, longer sleep onset latency, and higher fragmentation index, than the lowest quartile. Importantly, daytime and nighttime light levels were independently associated with objective sleep measures. CONCLUSION: The present study illustrated that greater daytime light exposure and lower nighttime light exposure are significantly associated with better objective sleep measures in patients with PD.

AIM: Sleep disturbance, a core feature of bipolar disorder, is closely associated with mood symptoms. We examined the association between actigraphy sleep parameters and mood episode relapses in patients with bipolar disorder. METHODS: This prospective cohort study analyzed 193 outpatients with bipolar disorder who participated in the Association between the Pathology of Bipolar Disorder and Light Exposure in Daily Life (APPLE) cohort study. The participants' sleep was objectively evaluated via actigraphy over 7 consecutive days for the baseline assessment and then at the 2-year follow-up appointment for mood episode relapses. The actigraphy sleep parameters were presented using the mean and variability (standard deviation) of each sleep parameter for 7 days. RESULTS: Of the 193 participants, 110 (57%) experienced mood episodes during follow-up. The participants with higher variability in total sleep time had a significantly shorter mean estimated time to mood episode relapses than those with lower variability (12.5 vs. 16.8 months; P < 0.001). The Cox proportional hazards model, when adjusted for potential confounders, demonstrated that variability in total sleep time was significantly associated with an increase in the mood episode relapses (per hour; hazard ratio [HR], 1.407; 95% confidence interval (CI), 1.057-1.873), mainly in the depressive episodes (per hour; HR, 1.477; 95% CI, 1.088-2.006). CONCLUSIONS: Our findings suggest that consistency in sleep time might be useful, as an adjunct therapy, in preventing the recurrence or relapse of mood episodes in bipolar disorder. This article is protected by copyright. All rights reserved.

BACKGROUND: Circadian activity rhythm disruption is a core feature in bipolar disorder. We investigated whether light exposure in daily life is associated with circadian activity rhythms in patients with bipolar disorder. METHODS: In a cross-sectional study, we enrolled 194 outpatients with bipolar disorder who were participants of the Association between Pathology of Bipolar Disorder and Light Exposure in Daily Life (APPLE) cohort study. The participants' physical activity and daytime illuminance were measured using an actigraph over 7 consecutive days. Nighttime illuminance in the bedroom was measured using a portable photometer. Circadian activity rhythm parameters were calculated using cosinor analysis and a nonparametric circadian rhythm analysis. RESULTS: The median daytime illuminance and nighttime illuminance were 224.5 lx (interquartile range, 154.5-307.5 lx) and 2.3 lx (0.3-9.4 lx), respectively. Multivariable linear regression analysis, adjusted for potential confounding factors, showed that higher daytime illuminance was significantly associated with higher amplitude and most active continuous 10-hour period, advanced acrophase, higher interdaily stability, and lower intradaily variability. Higher nighttime illuminance was significantly associated with lower relative amplitude, delayed onset of the least active continuous 5-hour period, and higher intradaily variability. LIMITATIONS: As this was a cross-sectional study, the results do not necessarily imply that light exposure alters circadian activity rhythms. CONCLUSIONS: Daytime light exposure was associated with a positive effect and nighttime light exposure with a negative effect on circadian activity rhythms in bipolar disorder.

AIM: Pharmacological treatments recommended for bipolar depression are inconsistent across guidelines. We compared the efficacy and safety of antipsychotics and mood stabilizers for bipolar depression. METHODS: A systemic review and meta-analysis of randomized controlled trials comparing antipsychotics and mood stabilizers for bipolar depression was conducted based on a literature search of major electronic databases. RESULTS: Three studies comparing quetiapine with lithium were identified and analyzed; no other antipsychotic-mood stabilizer combinations were found. The meta-analysis revealed no significant differences between quetiapine and lithium for the following outcomes: (1) remission from depressive episodes (risk ratio [RR]: 1.80, 95% CI: 0.51-6.40, P = 0.36), (2) changes in depressive symptom (standardized mean difference: -0.22, 95% CI: -0.52-0.08, P = 0.15), (3) changes in social function (standardized mean difference: -0.00, 95% CI: -0.19-0.18, P = 0.98), (4) suicide-related events (odds ratio [OR]: 2.35, 95% CI: 0.40-13.65, P = 0.34), (5) severe adverse events (OR: 1.63, 95% CI: 0.51-5.20, P = 0.41), (6) dropouts due to adverse events (RR: 1.19, 95% CI: 0.76-1.87, P = 0.45, 7) dropout for any reasons (RR: 0.95, 95% CI: 0.74-1.22, P = 0.70). CONCLUSION: Although this study found no differences in the efficacy and safety of quetiapine and lithium for bipolar depression, a comprehensive comparison of antipsychotics and mood stabilizers was not performed. Further studies are needed to clarify which of these, not just quetiapine and lithium, is more useful for bipolar depression.

OBJECTIVE: A previous cross-sectional study reported that nighttime light is associated with increased occurrence of manic symptoms in bipolar disorder; however, the longitudinal association between nighttime light and subsequent mood episode relapses remains unclear. We determined whether bedroom nighttime light was associated with mood episode relapses in patients with bipolar disorder. METHODS: This prospective cohort study included 172 outpatients with bipolar disorder who participated in an Association between the Pathology of Bipolar Disorder and Light Exposure in Daily Life (APPLE) cohort study. A portable photometer was used to measure illuminance in the bedroom from bedtime to rising time during 7 consecutive nights for baseline assessment. Then, the participants were assessed at a 2-year follow-up for mood episode relapses. RESULTS: Of the 172 participants, 157 (91%) completed the 2-year follow-up, and 39 (22%) experienced manic or hypomanic episodes (with or without mixed features), during that time. In the Cox proportional-hazards model, the hazard ratio (HR) for manic/hypomanic episode relapses was significantly higher when the average nighttime illuminance was ≥3 lux (n = 71) than when it was <3 lux (n = 101; HR, 2.54; 95% confidence interval (CI), 1.33-4.84). In the multivariable model adjusted for a propensity score in relation to nighttime light, the relationship remained significant (HR, 2.17; 95% CI, 1.04-4.52). The association between nighttime light and depressive episode relapses was not significantly different. CONCLUSIONS: Keeping the bedroom dark at night may prevent hypomanic and manic episodes.

Delayed sleep phase disorder (DSPD) and mood disorders have a close relationship. However, the shared mechanisms by DSPD and mood disorders have not been well-elucidated. We previously found that micro-fluctuations in human behaviors are organized by robust statistical laws (behavioral organization), where the cumulative distributions of resting and active period durations take a power-law distribution form and a stretched exponential functional form, respectively. Further, we found that the scaling exponents of resting period distributions significantly decreased in major depressive disorder (MDD). In this study, we hypothesized that DSPD had similar characteristics of the altered behavioral organization to that of MDD. Locomotor activity data were acquired for more than 1 week from 17 patients with DSPD and 17 age- and gender-matched healthy participants using actigraphy. We analyzed the cumulative distributions of resting and active period durations in locomotor activity data and subsequently derived fitting parameters of those distributions. Similar to patients with MDD, we found that resting period distributions took a power-law form over the range of 2-100 min, with significantly lower values of scaling exponents γ in patients with DSPD compared with healthy participants. The shared alteration in γ suggests the existence of similar pathophysiology between DSPD and MDD.

BACKGROUND: Sleep disturbance is a core feature of bipolar disorder; hence, sleep must be accurately assessed in patients with bipolar disorder. Subjective sleep assessment tools such as sleep diary and questionnaires are often used clinically for assessing sleep in these patients. However, the insight into whether these tools are as accurate as objective tools, such as actigraphy, remains controversial. METHODS: This cross-sectional study included 164 outpatients with a diagnosis of bipolar disorder, including patients who had euthymic and residual symptomatic periods. Objective sleep assessment was conducted prospectively using actigraphy for 7 consecutive days, whereas subjective sleep assessment was conducted prospectively using a sleep diary. RESULTS: The correlations were high and moderate between sleep diary and actigraphy when assessing the total sleep time and sleep onset latency, respectively (r = 0.81 and 0.47). These correlations remained significant after correction for multiple testing (both p < 0.001) and in both euthymic and residual symptomatic states (total sleep time: r = 0.86 and 0.77; sleep onset latency: r = 0.51 and 0.40, respectively). The median (interquartile ranges) of the percentage difference (sleep diary parameters minus actigraphy parameters divided by actigraphy parameter) in the total sleep time was relatively small (6.2% [-0.2% to 13.6%]). CONCLUSIONS: Total sleep time assessment using a sleep diary could be clinically useful in the absence of actigraphy or polysomnography.

A significant proportion of patients with bipolar disorder experience mood episode relapses. We examined whether circadian activity rhythms were associated with mood episode relapses in patients with bipolar disorder. This prospective cohort study included outpatients with bipolar disorder who participated in a study titled "Association between the Pathology of Bipolar Disorder and Light Exposure in Daily Life (APPLE) cohort study." The participants' physical activity was objectively assessed using a wrist-worn accelerometer over 7 consecutive days for the baseline assessment and then at the 12-month follow-up for mood episode relapses. The levels and timing of the circadian activity rhythms were estimated using a cosinor analysis and a nonparametric circadian rhythm analysis. Of the 189 participants, 88 (46%) experienced mood episodes during follow-up. The Cox proportional hazards model adjusting for potential confounders showed that a robust circadian activity rhythm, including midline-estimating statistic of rhythm (MESOR) and amplitude by cosinor analysis and 10 consecutive hours with the highest amplitude values (M10) by the nonparametric circadian rhythm analysis, was significantly associated with a decrease in mood episode relapses (per counts/min, hazard ratio [95% confidence interval]: MESOR, 0.993 [0.988-0.997]; amplitude, 0.994 [0.988-0.999]; and M10, 0.996 [0.993-0.999]). A later timing of the circadian activity rhythm (M10 onset time) was significantly associated with an increase in the depressive episode relapses (per hour; 1.109 [1.001-1.215]). We observed significant associations between circadian activity rhythms and mood episode relapses in bipolar disorder.

OBJECTIVE: Light therapy has been suggested to have a curative effect on bipolar depression; however, preventive effects of light exposure on depressive episodes remain unclear. This study evaluated whether daytime light exposure in real-life situations was associated with a preventive effect on relapse into depressive episodes in patients with bipolar disorder. METHODS: This prospective, naturalistic, observational study was conducted in Japan between August 2017 and June 2020. Outpatients with bipolar disorder were objectively evaluated for daytime light exposure over 7 consecutive days using an actigraph that could measure ambient light at baseline assessment and then assessed at 12-month follow-up for relapse into mood episodes. RESULTS: Of 202 participants, 198 (98%) completed follow-up at 12 months and 78 (38%) experienced relapse into depressive episodes during follow-up. In a Cox proportional hazards model adjusting for potential confounders, a longer time above 1000 lux at daytime was significantly associated with decrease in relapse into depressive episodes (per log min; hazard ratio, 0.66; 95% confidence interval, 0.50-0.91). In addition, a higher average illuminance and longer time above 1000 lux in the morning exhibited a significant decrease in relapse into depressive episodes (per log lux and per log min; hazard ratio, 0.65 and 0.61; 95% confidence interval, 0.49-0.86 and 0.47-0.78, respectively). The association between daytime light exposure and relapse into manic/hypomanic/mixed episodes was not significantly different. CONCLUSION: A significant association was observed between increased daytime light exposure, mainly in the morning, and decreased relapse into depressive episodes.

OBJECTIVE: Sleep disturbance, a core feature of bipolar disorder, is associated with residual mood symptoms, mood episode recurrence and suicide ideation. We investigated the effect of evening light exposure on sleep in patients with bipolar disorder. METHODS: In this longitudinal analysis, we measured the sleep parameters of 207 outpatients with bipolar disorder using actigraphy at their homes for seven consecutive nights. We measured the white-light illuminance and the irradiance of each wavelength during the 4 hours before each participant's bedtime. We used mixed-effect linear regression analysis for repeated measures to evaluate the effect of evening light exposure on subsequent sleep parameters. RESULTS: The median white-light illuminance was 25.8 lux (interquartile range, 12.9-50.1 lux). In a multivariable model adjusted for potential confounders, we found higher white-light illuminance to be significantly associated with lower sleep efficiency (per log lux: 95% confidence interval = [-1.328, -0.133]; p = 0.017), prolonged sleep-onset latency (95% confidence interval = [0.006, 0.172]; p = 0.035) and longer wake after sleep onset (95% confidence interval = [1.104, 4.459]; p = 0.001). This effect size was larger in the younger age group (aged < 44 years) stratified by median age. Higher irradiance of the blue wavelength range was significantly associated with longer wake after sleep onset, a result similar to those for the green and red wavelength ranges. CONCLUSION: We observed significant associations between evening light exposure and subsequent sleep in patients with bipolar disorder. The effects of various light wavelengths on sleep in bipolar disorder require further investigation.

Obesity and overweight are highly prevalent in individuals with bipolar disorder and are associated with a risk of developing not only physical but also mental problems. The current study aimed to determine the association between bedroom light exposure at night and obesity in individuals with bipolar disorder. This cross-sectional study enrolled 200 outpatients with bipolar disorder. The light intensity in the bedroom between bedtime and rising time was measured for seven consecutive nights using a portable photometer. Body mass index (BMI) was determined using self-reported height and weight, and obesity was defined as a BMI ≥ 25 kg/m2. The overall prevalence of obesity was 44%. In the multivariable logistic regression analysis adjusted for age, gender, use of psychiatric medications, sleep parameters, and physical activity, the odds ratio (OR) for obesity was significantly higher in the group exposed to an average light intensity ≥ 3 lux (n = 112) than in the group exposed to an average light intensity < 3 lux (n = 88) (OR, 2.13; 95% confidence interval, 1.19-4.21; P = 0.01). Furthermore, individuals exposed to an average light intensity ≥ 3 lux were significantly higher body weight (adjusted mean, 68.7 vs. 64.4 kg; P = 0.03) and BMI (adjusted mean, 25.6 vs. 24.2 kg/m2; P = 0.04) than those exposed to an average light intensity < 3 lux. A significant association was observed between bedroom light exposure at night and obesity in patients with bipolar disorder. Further longitudinal investigations are necessary to clarify this association.

BACKGROUND: Patients with bipolar disorder (BD) frequently self-harm, and this is strongly associated with subsequent suicide. This study investigated the association between chronotype and intentional self-harm in patients with BD. METHODS: Two-hundred and five outpatients with BD participated in this cross-sectional study. Each participant's chronotype was evaluated using the Morningness-Eveningness Questionnaire, dividing the scores into three types: evening, 16-41 points; intermediate, 42-58 points; and morning, 59-86 points. Intentional self-harm over the past year were self-reported by questionnaire. Propensity score for evening chronotype was estimated from age, sex, socioeconomic factors, mood symptoms, total sleep time, age at the onset of BD, psychiatric inpatient history, family history of suicide, psychiatric comorbidity, and use of lithium. RESULTS: Thirty-six (18%) of the 205 participants reported self-harm. A substantially higher proportion of the evening chronotype group self-harmed compared to the other groups (evening, 37%; intermediate, 13%; morning 10%). In multivariable analysis adjusted for propensity score, the odds ratio (OR) for self-harming significantly increased from morning to intermediate to evening chronotype (ORs: morning, 1.00; intermediate, 1.56; evening, 3.61; P for trend = 0.038). LIMITATIONS: This study was a cross-sectional and small sample size. CONCLUSIONS: Although a third factors, such as personality disorder or disrupted circadian rhythm, may have influenced, these findings suggest association between chronotype and intentional self-harm in BD patients.

OBJECTIVES: Recent studies have suggested that evening blue light exposure is associated with sleep and circadian rhythm abnormalities. This study examined the effect of blue-blocking (BB) glasses on sleep and circadian rhythm in patients with bipolar disorder (BD). METHODS: We used a randomized, placebo-controlled, double-blinded design. Outpatients with BD and also with insomnia were randomly assigned to wear either orange glasses (BB) or clear ones (placebo) and were instructed to use these from 20:00 hours until bedtime for 2 weeks. The primary outcome metric was the difference in change from baseline to after intervention in sleep quality, as measured by the visual analog scale (VAS). RESULTS: Forty-three patients were included in this study (BB group, 21; placebo group, 22). The change in sleep quality as per the VAS metric was not significantly different between the two groups (95% confidence interval [CI], -3.34 to 24.72; P = .13). However, the Morningness-Eveningness Questionnaire score had shifted to an advanced rhythm in the BB group and to a delayed rhythm in the placebo group, and the difference in these changes was statistically significant (95% CI, 1.69-7.45; P = .003). The change in the actigraphy sleep parameters and mood symptoms was not significantly different between the two groups. CONCLUSION: Although concurrent medications may have influenced, our results suggest that BB glasses may be useful as an adjunctive treatment for circadian rhythm issues in patients with BD.

Previous studies have found that keeping the room dark at night was associated with a decrease in manic symptoms for patients with bipolar disorder (BD). However, the association between light at night of real-life conditions and manic symptoms is unclear. We investigated the association between bedroom light exposure at night and manic symptoms in BD patients. One-hundred and eighty-four outpatients with BD participated in this cross-sectional study. The average light intensity at night during sleep was evaluated using a portable photometer for seven consecutive nights. Manic symptoms were assessed using the Young Mania Rating Scale (YMRS), and scores ≥5 were treated as a "hypomanic state." The median (interquartile range) YMRS score was 2.0 (0-5.0), and 52 (28.2%) participants were in a hypomanic state. The prevalence of a hypomanic state was significantly higher in the participants with an average light intensity at night exposure of ≥3 lux than in those with <3 lux (36.7% versus 21.9%; P = .02). In multivariable logistic regression analysis adjusted for BD type, depressive symptoms, sleep duration, and daytime physical activity, the odds ratio (OR) for a hypomanic state was significantly higher for the participants with an average light intensity at night exposure of ≥3 lux than for those with <3 lux (OR: 2.15, 95% confidence interval: 1.09-4.22, P = .02). This association remained significant at the cutoff value of YMRS score ≥6 (OR: 2.51, 95% confidence interval: 1.15-5.46; P = .02). The findings of this study indicate bedroom light exposure at night is significantly associated with manic symptoms in BD patients. Although the results of this cross-sectional investigation do not necessarily imply causality, they may serve to inform beneficial nonpharmacological intervention and personalized treatment of BD patients.

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.

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.

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.

The objective of the study was to investigate the efficacy of ramelteon for insomnia, particularly with circadian disturbance, focusing on the relevance of dose and timing of administration. We reviewed the chart data of 145 continuous patients who received ramelteon for insomnia for the first time at the sleep clinic of the Department of Psychiatry, Fujita Health University Hospital (Aichi, Japan) between October 2010 and May 2014. Treatment efficacy was assessed using the Clinical Global Impression of Improvement (CGI-I) scale and this relationship with the dose and timing of administration was further analyzed. Symptoms in 56.6% of patients were improved (CGI-I ≦ 3). In a subgroup of 114 patients, especially aiming for phase advance, the ratio of improvement was 64.0%. The ratio of patients reporting symptom improvement tended to be great in the low-dose (1 or 2 mg) group and the low-dose + early administration (&gt 5 h before habitual bedtime) group, as compared with the remaining group however, this difference was not statistically significant. Significantly fewer cases in the low-dose group reported carry-over effects. In our specialized sleep clinic, there were many refractory cases of insomnia however, ramelteon was effective in about half of such patients. Particularly, ramelteon tended to be more effective for patients with insomnia and circadian disturbances, although differences among groups were not statistically significant. The effectiveness of the low-dose administration or the combination of low-dose and early-administration was equal or slightly better and acceptability tended to be better than other modes of administration.

We describe a case of parasomnia overlap disorder (POD) caused by paroxetine. Some reports have associated antidepressants such as selective serotonin reuptake inhibitors (SSRI) with rapid eye movement sleep behavior disorder. However, to the best of our knowledge, there have been no reports of POD caused by paroxetine. We diagnosed POD in a patient taking paroxetine using video-polysomnography (v-PSG) and then confirmed the improvement of POD symptoms by v-PSG after discontinuing the drug.

Blue wavelengths form the portion of the visible electromagnetic spectrum that most potently regulates circadian rhythm. We hypothesized that wearing blue-blocking (BB) glasses in the evening may influence circadian rhythm disturbances in patients with major depressive disorder (MDD), resulting in improved sleep and mood. We used a randomized placebo-controlled double-blinded design. Patients with MDD with sleep onset insomnia were randomly assigned to wearing either BB glasses or clear glasses (placebo). Patients were instructed to wear the glasses from 20:00 hours until bedtime for 2 weeks. We assessed sleep state (sleep quality on a visual analog scale, the Morningness-Eveningness Questionnaire [MEQ], and a sleep diary) and depressive symptoms at baseline and after 2 weeks. Data were analyzed with a full analysis set. In total, 20 patients were randomly assigned to the BB and placebo groups (BB group, n = 10; placebo group, n = 10). There were three dropouts (BB group, n = 1; placebo group, n = 2). At baseline, sleep quality, sleep latency (assessed via a sleep diary), and antipsychotics use differed between the groups. To take account of these differences, the baseline sleep state or depressive symptoms and antipsychotics use were used as covariates in the later analysis. The change scores for sleep quality did not show a significant improvement in the BB group compared with the placebo group (mean [standard deviation, SD] scores for BB versus placebo: 36.1 [31.7] versus 16.2 [15.1], p = 0.43), although half of the BB group showed a clear improvement in sleep quality. The change in MEQ scores did not significantly differ between the groups (p = 0.14), although there was a trend of a shift to morning type in the BB group (3.10 [4.95] points) and to evening type in the placebo group (0.50 [3.89] points). There were no statistically significant changes in depressive symptoms in either group. Across both groups, 40% of the participants reported pain or discomfort from wearing the glasses, which were available in only one size. Thus, the failure to find significant differences may have resulted from the glasses used in this study. Glasses fitted to individual patients may improve efficacy and safety. Replication of the study with a larger sample size and size-adjustable glasses is needed.

STUDY OBJECTIVES: Patients with circadian rhythm sleep disorders (CRSDs) often have coincidence of orthostatic dysregulation (OD). Both disorders have many common clinical features. However, the prevalence of OD in patients with CRSD has not been examined. METHODS: Thirty-eight patients with CRSD with either delayed sleep phase disorder or free-running disorder were tested for OD using the new orthostatic test, which was originally established by Tanaka et al. (< 20 years) and the Schellong test, i.e., the active standing test (≥ 20 years). RESULTS: The overall prevalence of OD in patients with CRSD was 57.9% (22/38), and prevalence of OD was 70% in patients under 20 years of age (14/20). These rates exceed the previously reported values in adolescents aged 14-15 years (15%), regarded as the age with highest OD prevalence. Prevalence was not significantly associated with CRSD severity and medications used. CONCLUSIONS: We observed a high prevalence of OD in patients with CRSD, suggesting some relationship between CRSD and OD. Large-scale case-control studies are warranted to investigate the underlying mechanisms for this comorbidity.

STUDY OBJECTIVES: Rapid eye movement (REM) sleep behavior disorder (RBD) is a parasomnia characterized by REM sleep without atonia and elaborate motor activity in association with dream mentation. The melatonin receptor agonist ramelteon has been documented as being effective in two patients with secondary RBD. However, there are no reports on ramelteon treatment for idiopathic RBD. METHODS: In an open-labeled trial, we treated 12 consecutive patients with idiopathic RBD for at least 4 w with 8 mg ramelteon given within 30 min before bedtime. RESULTS: Ramelteon treatment did not have a clear effect on REM sleep without atonia or an RBD severity scale measured by video-supported polysomnography. However, clinical assessment using a visual analog scale showed a trend toward significance and there were also definitely positive changes in some individual cases. Ramelteon was well tolerated in most patients, with minor side effects. CONCLUSIONS: Considering that ramelteon is associated with few side effects, further study may ascertain whether patients with RBD could be effectively treated by ramelteon, especially when clonazepam may not be suitable due to its side effects. COMMENTARY: A commentary on this article appears in this issue on page 643.

It has been recently discovered that blue wavelengths form the portion of the visible electromagnetic spectrum that most potently regulates circadian rhythm. We investigated the effect of blue light-blocking glasses in subjects with delayed sleep phase disorder (DSPD). This open-label trial was conducted over 4 consecutive weeks. The DSPD patients were instructed to wear blue light-blocking amber glasses from 21:00 p.m. to bedtime, every evening for 2 weeks. To ascertain the outcome of this intervention, we measured dim light melatonin onset (DLMO) and actigraphic sleep data at baseline and after the treatment. Nine consecutive DSPD patients participated in this study. Most subjects could complete the treatment with the exception of one patient who hoped for changing to drug therapy before the treatment was completed. The patients who used amber lens showed an advance of 78 min in DLMO value, although the change was not statistically significant (p = 0.145). Nevertheless, the sleep onset time measured by actigraph was advanced by 132 min after the treatment (p = 0.034). These data suggest that wearing amber lenses may be an effective and safe intervention for the patients with DSPD. These findings also warrant replication in a larger patient cohort with controlled observations.

A sleep diary is often employed for diagnosing and treating hypersomnia. However, its reliability needs to be evaluated because overlooked chronic sleep insufficiency could be misdiagnosed as narcolepsy. In this study, we compared simultaneous sleep measurements using a sleep diary and by actigraphy in patients visiting our sleep clinic for the first time with complaints of excessive daytime sleepiness. Of the 28 patients enrolled, 24 complied with both these requirements. In this population, the results obtained using a sleep diary tended to estimate a statistically significant earlier sleep onset time and longer total sleep time than those via actigraphy. For total sleep time, this tendency was more prominent in patients with a higher Epworth Sleepiness Scale score. In 5 of the 24 (20.8%) patients, the sleep diary records indicated >6h of total sleep time while the actigraphy records indicated <6h of total sleep time, with a discrepancy of >1h. These results suggested that sleep insufficiency in hypersomnia patients may be overlooked when their sleep time is assessed using only a sleep diary in the initial phase of the diagnostic procedure, and the simultaneous use of actigraphy may be preferable in this assessment.

Patients with schizophrenia frequently exhibit behavioral abnormalities associated with its pathological symptoms. Therefore, a quantitative evaluation of behavioral dynamics could contribute to objective diagnoses of schizophrenia. However, such an approach has not been fully established because of the absence of quantitative biobehavioral measures. Recently, we studied the dynamical properties of locomotor activity, specifically how resting and active periods are interwoven in daily life. We discovered universal statistical laws ("behavioral organization") and their alterations in patients with major depressive disorder. In this study, we evaluated behavioral organization of schizophrenic patients (n = 19) and healthy subjects (n = 11) using locomotor activity data, acquired by actigraphy, to investigate whether the laws could provide objective and quantitative measures for a possible diagnosis and assessment of symptoms. Specifically, we evaluated the cumulative distributions of resting and active periods, defined as the periods with physical activity counts successively below and above a predefined threshold, respectively. Here we report alterations in the laws governing resting and active periods; resting periods obeyed a power-law cumulative distribution with significantly lower parameter values (power-law scaling exponents), whereas active periods followed a stretched exponential distribution with significantly lower parameter values (stretching exponents), in patients. Our findings indicate enhanced persistency of both lower and higher locomotor activity periods in patients with schizophrenia, probably reflecting schizophrenic pathophysiology.