Incidence of depression among community-dwelling older adults: A systematic review

We aimed to synthesise information related to the incidence of depression and depressive symptoms (DDS) in a community-dwelling older adult population at a global level. In this systematic review, we included articles with a cohort study design that evaluated the incidence of depression or depressive symptoms in older adults aged 60 years or more in a community-dwelling environment. Six databases were used: Web of Science, PubMed, Scopus, LILACS, SciELO, and Cochrane, and the entire selection process was independently performed by peers. We divided the included articles into subgroups according to the DDS assessment instrument: (i) Geriatric Depression Scale; (ii) Center for Epidemiologic Studies Depression Scale; (iii) miscellaneous scales; and (iv) diagnostic interviews. Each cumulative incidence value obtained per item was adjusted for a 1-year follow-up period, which generated an annual cumulative incidence (AcI). From 46 articles, 42 used scales to evaluate the depressive variable, with an AcI estimate of around 4.5%. The articles that assessed depression categorically observed a variation in AcI between 0.2% and 7.0%. Among all the materials included, the group that used the Geriatric Depression Scale observed the lowest and the highest AcI, 1.3% and 26.6% respectively. Most of the productions were from countries in the Asian continent (52.2%), followed by Europe (30.4%), the Americas (13%), and Oceania (4.4%). Despite the variation of AcI, we found a frequent occurrence of DDS in older adults in the community-dwelling environment, which highlights the need for preventive actions and better-targeted early care, especially in terms of primary health care.