Clinically significant non-major depression in a community-dwelling elderly population: epidemiological findings

Objective The aim of this study was to investigate the 1-month prevalence, symptom profiles and demographic correlates in late-life clinically significant non-major depression (CSNMD) among a community-dwelling elderly population. Methods One thousand five hundred subjects aged 65 years and older, who were randomly selected from three communities in Taiwan, received comprehensive psychiatric assessment by trained psychiatrists. Two categorical diagnoses of depressive disorder, including major depression and CSNMD, were made. The 1-month prevalence was calculated. Frequencies of depressive symptoms across CSNMD and major depression were compared. The risks of CSNMD based on demographic characteristics were estimated using multinominal logistic regression. Results The 1-month prevalence of CSNMD among the community-dwelling elderly was 8.8%. Symptoms of diminished interest, appetite changes, sleep disturbance, worthlessness or inappropriate guilt, trouble in concentrating or indecisiveness, and suicidal thoughts or acts were less frequent in CSNMD than in major depression, but symptoms of depressed mood, psychomotor changes, and fatigue or loss of energy were as frequent in both categories of illness. CSNMD shares similar demographic risks, such as living in an urban area, female gender and low educational status, with major depression. Conclusions CSNMD is common among community-dwelling elders in Taiwan, and with its identical demographic characteristics, but qualitatively different presentation, we suggest CSNMD may be considered part of a spectrum of severe late life depressions with a distinct manifestation. Major depression and CSNMD may share common demographic characteristics with different manifestation. We conclude that late-life depression is a dimensional disease. Copyright (c) 2006 John Wiley & Sons, Ltd.