Yuichi Esaki

INTRODUCTION: Circadian dysfunction is involved in the pathophysiology of bipolar disorders (BD), and circadian-based interventions are gaining recognition in their management. Moreover, basic and epidemiologic research has generated findings inspiring circadian-informed self- and clinician-management strategies. Despite these gains, many Clinical Practice Guidelines and clinical training programs have not incorporated this evidence in their recommendations and curricula. This International Society for Bipolar Disorders (ISBD) Chronobiology and Chronotherapy Task Force position paper reports a Delphi-based expert consensus on what is essential for mental health clinicians to know about the chronobiology and chronotherapy of BD. METHODS: An initial pool of statements was extracted from academic and grey literature, and experts could suggest additional statements. Statements were rated on a 5-point scale ('essential'; 'important'; 'don't know/depends'; 'unimportant'; 'should not be included'). Consensus was reached when statements were rated as essential or important by ≥ 80% of experts. RESULTS: Thirty experts from 15 countries in Europe, North and South America, and the Asia Pacific participated (mean age of 55.3 years [SD = 11.8]; 40% female; 83% psychiatrists; mean clinical experience of 26 years [SD = 10.8]). Eight-hundred-and-thirty-seven statements were rated across three rounds. Consensus was reached on 342 statements spanning four major themes: basic circadian science; circadian health and disruption; chronobiology of BD; and six chronotherapies (e.g., protocols, outcomes, risks/contraindications). CONCLUSIONS: An expert consensus was obtained on the essential information about the chronobiology and chronotherapy of BD, intended to help clinicians optimise their management of BD. Dissemination of this knowledge is expected to enhance the training and efficacy of clinicians.

STUDY OBJECTIVES: Accumulating evidences have investigated the impact of nighttime light exposure on metabolic dysfunction, including obesity, hypertension, diabetes, and dyslipidemia, in the general population. However, no study has investigated this effect in patients with schizophrenia. Therefore, this study aimed to investigate the association between nighttime light exposure and metabolic dysfunction in patients with schizophrenia. METHODS: This was a cross-sectional study including 222 outpatients with schizophrenia enrolled in the Light Exposure and Neurobiology in Schizophrenia (LENS) study. Nighttime light exposure was objectively evaluated using a wrist-worn actigraph and a bedside photometer over 7 consecutive days. Physical examinations and blood sampling were performed at the clinic. RESULTS: After adjusting for potential confounding factors, multivariable logistic regression analysis revealed that the participants with the highest quartile of nighttime illuminance measured using actigraphy had significantly higher odds ratios (OR) for obesity (OR, 4.01; 95% confidence interval [CI], 1.69-9.53), hypertension (OR, 3.38; 95% CI, 1.40-8.18), and dyslipidemia (OR, 2.41; 95% CI, 1.01-5.74) than those with the lowest quartile. No significant association was observed between nighttime illuminance and OR for diabetes. However, increased nighttime illuminance was significantly associated with higher glycosylated hemoglobin levels. A significant association was observed between nighttime illuminance measured using the bedside photometer and OR for hypertension. CONCLUSION: We found a significant association between nighttime light exposure and metabolic dysfunction in patients with schizophrenia. Further longitudinal studies are needed to clarify this association.