Prospective study of chronotype and incident depression among middle- and older-aged women in the Nurses' Health Study II.

J Psychiatr Res
Authors
Keywords
Abstract

BACKGROUND: Prior cross-sectional studies have suggested that being a late chronotype is associated with depression and depressive symptoms, but prospective data are lacking.

METHODS: We examined the association between chronotype and incident depression (defined as self-reported physician/clinician-diagnosed depression or antidepressant medication use) in 32,470 female participants of the Nurses' Health Study II cohort who self-reported their chronotype (early, intermediate or late) and were free of depression at baseline in 2009 (average age: 55 yrs). Women updated their depression status on biennial questionnaires in 2011 and 2013. We used multivariable (MV)-adjusted Cox proportional hazards models to estimate hazard ratios (HR) and 95% confidence intervals (95%CI) for incident depression across chronotype categories (i.e., early, intermediate, and late chronotypes).

RESULTS: Across a follow-up period of 4 years, we observed 2,581 cases of incident depression in this cohort. Compared to intermediate chronotypes, early chronotypes had a modestly lower risk of depression after MV adjustment (MVHR = 0.88, 95%CI = 0.81-0.96), whereas late chronotypes had a similar risk of 1.06 (95%CI = 0.93-1.20); the overall trend across chronotype categories was statistically significant (ptrend0.01). Results were similar when we restricted analyses to women who reported average sleep durations (7-8 h/day) and no history of rotating night shift work at baseline.

CONCLUSIONS: Our results suggest that chronotype may influence the risk of depression in middle-to older-aged women. Additional studies are needed to confirm these findings and examine roles of both environmental and genetic factors to further our understanding of the role of chronotype in the etiology of mood disorders.

Year of Publication
2018
Journal
J Psychiatr Res
Volume
103
Pages
156-160
Date Published
2018 08
ISSN
1879-1379
DOI
10.1016/j.jpsychires.2018.05.022
PubMed ID
29860110
PubMed Central ID
PMC6016366
Links
Grant list
R01 OH009803 / OH / NIOSH CDC HHS / United States
R01OH009803 / ACL HHS / United States
R21 OH011052 / OH / NIOSH CDC HHS / United States
UM1 CA176726 / CA / NCI NIH HHS / United States