The Impact of Sleep Disturbance on the Association Between Stressful Life Events and Depressive Symptoms.
OBJECTIVE
Sleep problems are common across the adult life span and may exacerbate depressive symptoms and the effect of common risk factors for depressive symptoms such as life stress. We examine sleep disturbance as a moderator of the association between stressful life events and depressive symptoms across five waves (25 years) of the nationally representative, longitudinal American Changing Lives Study.


METHODS
The sample includes 3,597 adults aged 25 years or older who were surveyed up to five times over 25 years. Multilevel models were run to examine between- and within-person variability in sleep disturbance and life event stress as predictors of depressive symptoms, and an interaction to test sleep disturbance as a moderator is included in a second step.


RESULTS
Life events and sleep disturbance were associated with elevated depressive symptoms at the between- and within-person levels. A significant sleep disturbance by interaction of life events was found, indicating that when individuals experienced an above average number of life events and slept more restlessly than usual, they had a higher risk for depressive symptoms than individuals who experienced above average stress but slept well.


CONCLUSIONS
Sleeping restfully may allow individuals the rejuvenation needed to manage stress adaptively and reduce depressive symptom burden.
Department of Psychiatry, University of Michigan Medical School, Ann Arbor. leggetta@med.umich.edu.
Amanda
A
Leggett
Department of Sociology, University of Michigan Ann Arbor. Population Studies Center, Institute for Social Research, University of Michigan, Ann Arbor.
Sarah
S
Burgard
Department of Psychiatry, University of Michigan Medical School, Ann Arbor. Department of Veterans Affairs, Center for Clinical Management Research, Ann Arbor, Michigan.
Kara
K
Zivin
D000328:Adult; D000368:Aged; D003863:Depression / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control; D005260:Female; D006801:Humans; D008016:Life Change Events; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D011316:Preventive Psychiatry / Q000379:methods; D011379:Prognosis; D011569:Psychiatric Status Rating Scales; D012307:Risk Factors; D012893:Sleep Wake Disorders / Q000150:complications* / Q000175:diagnosis / Q000453:epidemiology / Q000523:psychology; D013315:Stress, Psychological / Q000150:complications* / Q000175:diagnosis / Q000453:epidemiology; D014481:United States / Q000453:epidemiology
Depressive symptoms; Sleep disturbance; Stressful life events