RESUMO
OBJECTIVES: (1) To describe the prevalence of minor depression in a community-dwelling population aged 80 years and over. (2) To compare the sleep pattern, memory function and the prevalence rate of other psychiatric diagnoses between normal controls and subjects with minor depressive disorder. DESIGN: A random representative sample (sample=77 subjects/county population of oldest-old =219--35%) aged 80 years or more was selected from the county of Veranópolis in the Brazilian rural southern region. Of this group, eight subjects who met the DSM-IV criteria for minor depression, and 50 subjects without diagnosed delirium disorder, cognitive or affective problems were compared. RESULTS: The prevalence rate of minor depression was 12%. Subjects with this diagnosis were more likely to complain about sleep and memory problems than elderly people without any other affective disorder (major depression or dysthymic disorder). Otherwise, objective evaluation of these two areas, memory and sleep, did not show differences between the groups. Moreover, in terms of factors such as life satisfaction and some domains from the Short-form 36 Quality of Life Scale (SF-36), subjects with minor depression presented worse self-reported evaluations. Female gender was associated (p=0.01) with a more frequent presence of minor depression disorder, and those with this diagnosis were more likely to have co-morbidity with generalized anxiety disorder (p=0.007) when compared with elderly people without any depressive disorder. CONCLUSION: In this study, minor depression has been significantly associated with lower life satisfaction and worse indexes of life quality. The results supported the current concept that minor depression is prevalent in later life, especially among the oldest-old. Subjects with minor depression had worse self-reported opinions about memory and sleep patterns, but when these variables were objectively measured, no meaningful differences could be determined by the research team. Female gender and the concurring presence of generalized anxiety disorder were both significantly associated with the presence of minor depression diagnosis.