Atypical depression has been found to be distinct from other types of depression in terms of psychiatric symptom profile and treatment response. However, debate continues regarding its specific characteristics, impact, and diagnostic criteria. The current study was conducted to increase understanding of atypical depression diagnosed using only the reversed vegetative symptoms of hypersomnia and hyperphagia.
An atypical depression group (n = 304 [36.4% of the depressed sample; 39.0% when weighted to approximate the national population]) was identified within the US National Comorbidity Survey, which assessed psychiatric disorders among a nationally representative sample using the Composite International Diagnostic Interview. The atypical group was identified based on DSM-III-R criteria for a major depressive episode, in addition to atypical features of hypersomnia and hyperphagia. Comparison groups were those with nonatypical depression (n = 532) and individuals without a psychiatric disorder(n = 4071).
Compared with nonatypical depression, atypical depression was associated with a greater percentage of women and an earlier age of onset. The atypical group also reported higher rates of most depressive symptoms, suicidal thoughts and attempts, psychiatric comorbidity (panic disorder, social phobia, and drug dependence), disability and restricted activity days, use of some health care services, paternal depression, and childhood neglect and sexual abuse(P<.05). Compared with people without psychiatric disorders, the atypical group reported higher rates of disability and restricted activity days, use of all mental health care services, parental depression, and childhood abuse (P<.001).
This analysis of a nationally representative US sample suggests that overeating and oversleeping can be used to identify an atypical depression subgroup that is distinct from other depressed patients in terms of demographics, psychiatric comorbidities, and abuse history. Findings also suggest that atypical depression is associated with increased distress, suicidal ideation, and disability compared with nonatypical depression.