OBJECTIVES:
We hypothesized that depressive symptoms not meeting full standard criteria for Major Depression would be associated with significant functional impairment among older adults over the course of a 13-year follow-up interval. Specifically, we developed criteria for a form of depression whose core symptoms did not include sadness or dysphoria.
DESIGN:
Population-based 13-year follow-up survey.
SETTING:
Community-dwelling adults living in East Baltimore in 1981.
PARTICIPANTS:
Subjects were the 1612 participants of the Baltimore sample of the Epidemiologic Catchment Area Program aged 50 years and older at the initial interview in 1981.
MEASUREMENTS:
The subjects were sorted into four categories based on their responses at baseline: (1) persons meeting standard criteria for Major Depression; (2) persons meeting alternative criteria for depression with dysphoria or (3) without dysphoria; and (4) a comparison category of persons not meeting any criteria for depression ("noncases"). The mortality and functional status of each group were compared after a 13-year follow-up interval.
RESULTS:
Compared with non-cases, participants aged 50 years and older who reported depressive symptoms but who denied sadness or dysphoria (nondysphoric depression) were at increased risk for death (relative risk (RR) = 1.70; 95% confidence interval (CI) (1.09, 2.67)), impairment in activities of daily living (RR = 3.76; 95% CI (1.73, 8.14)), impairment in instrumental activities of daily living (RR = 5.07; 95% CI (2.24, 11.44)), psychologic distress (RR = 3.68; 95% CI (1.47, 9.21)), and cognitive impairment (RR = 3.00; 95% CI (1.31, 6.89)) after a 13-year follow-up interval. The findings were not wholly explained by potentially influential baseline characteristics such as age, education, selected comorbid medical conditions, and functional status.
CONCLUSION:
Among adults aged 50 years and older, nondysphoric depression may be as important as Major Depression in relation to the development of functional disability and other long-term outcomes.