Comorbid depression and anxiety in later life: patterns of association, subjective well-being, and impairment.

Objective: Very little epidemiological work has examined comorbidity between depression and anxiety disorders in community-dwelling older adults, despite the fact these disorders are known to co-occur in younger adults and that this co-occurrence is associated with greater clinical severity. In this study, the authors examine psychiatric comorbidity and associated impairment of four disorders (major depression, panic disorder, social phobia, and agoraphobia) in a community-based sample of adults aged 55 and older.

Setting: Population-based sample of older adults (N=12,792) from the Canadian Community Health Survey-Mental Health and Well-Being (CCHS 1.2).

Method: The World Mental Health Composite International Diagnostic Interview was used to identify cases of 12-month disorder. Descriptive analysis and regression analysis is used to examine patterns of association between disorders and related impairment.

Results: Among adults aged 55 years and older, 4.4% met the criteria for at least one disorder and 0.8% had two or more. Social phobia was the most common comorbid disorder among respondents with depression, and depression was the most common comorbid disorder among respondents with any of the anxiety disorders. Respondents who report comorbid disorders reported significantly lower well-being and greater impairment.

Conclusion: Although comorbidity between physical health conditions and depression, and between dementias and depression, are well documented among older adults, these results suggest that comorbid depression and anxiety are also prevalent in later life. The significant impact of comorbidity on function and well-being underlines the need to screen for comorbid disorders in this population.