The impact of depressive symptoms and chronic diseases on active life expectancy in older Americans.

Objectives: The authors prospectively examined whether depressive symptoms (DS) in older adults negatively affected active live expectancy (ALE), or remaining years free of disability, and mortality, independently and in the presence of chronic diseases, and after stratification by gender.

Design: Prospective cohort study, first three waves (1993-1998) of the Asset and Health Dynamics Among the Oldest Old.

Data Collection: University of Michigan; analysis: University of South Florida.

Participants: Nationally representative sample of community-dwelling adults age 70 and older (N = 7,381).

Measurements: DS (Center for Epidemiological Studies Depression, 8-item version), self-reported cancer, diabetes, heart disease, or stroke, difficulty with activities of daily living, death, and estimates of total, active, and disabled life expectancy.

Results: DS reduced ALE by 6.5 years for young-old men (age 70), 3.2 years for old-old men (age 85), 4.2 years for young-old women, and 2.2 years for old-old women, and these effects remained significant at all ages and across gender even after controlling for chronic disease, the one exception being DS and cancer in old-old women. DS also reduced total life expectancy significantly, although controlling for some chronic diseases (particularly cancer and stroke) eliminated the effect of DS across age and gender groups.

Conclusion: Depressive symptoms represent a serious and distinct threat to independent functioning in older adults. Whether experienced alone, or in combination with chronic diseases, depressive symptoms shorten ALE substantially. Timely diagnosis and treatment of depressive symptoms in older adults may delay the onset of disability and improve the quality of life.