Daytime Sleepiness and Insomnia as Correlates of Depression

Insomnia and daytime sleepiness are often associated with depression. The possible relationshipsbetween sleep difficulties and depression are numerous. Insomnia and other sleep disturbances can beprecursors to the onset of major depressive disorder, so they may act as risk factors for or predictors ofdepression. The symptomatology of depression also prominently includes insomnia, and sleep disturbancesmay be residual symptoms after response to antidepressant treatment. Insomnia and the resultantdaytime sleepiness may be short-term or long-term side effects of antidepressant treatment aswell. Whether insomnia is a precursor, symptom, residual symptom, or side effect of depression or itstreatment, clinicians must give serious attention to and attempt to resolve sleep disturbances becauseof the risk of depression onset, worsening of depressive symptoms, and relapse of depression afterresponse to antidepressant treatment. Remission of depression cannot be fully achieved until the associatedinsomnia and daytime sleepiness are resolved. This article describes the relationships betweeninsomnia and depression and discusses the effects of various antidepressants on sleep. Finally, severaldifferent treatment options, including antidepressant monotherapy and augmentation of antidepressantswith other medications, are explored.