Depression and excess mortality in the elderly living in low- and middle-income countries: Systematic review and meta-analysis

Abstract

Objective: To investigate the association between depression and mortality in the elderly living in low- and middle-income countries.

Methods: A systematic review and meta-analysis was performed. We searched in five electronic databases for observational studies investigating the association between mortality and depression. Two reviewers worked independently to select articles, extract data, and assess study quality.

Results: A total of 10 studies including 13 828 participants (2402 depressed and 11 426 nondepressed) from six countries (Brazil, four articles; China, two articles; Botswana, India, South Africa, and South Korea, one article) were included. The overall unadjusted relative risk (RR) of mortality in depressed relative to nondepressed participants was 1.62 (95% CI, 1.39-1.88; P < 0.001), with high heterogeneity (I² = 66%; 95% CI, 33-83; P < 0.005). After adjustment for publication bias, the overall RR decreased to 1.60 (95% CI, 1.37-1.86; P < 0.001). No significant differences were observed between subgroups except those defined by study quality. The high-quality studies had a pooled RR of 1.48 (95% CI, 1.32-1.67; P < 0.001), while the low-quality studies resulted had a pooled RR of 1.82 (95% CI, 1.25-2.65; P < 0.005).

Conclusions: Depression is associated with excess mortality in the elderly living in low- and middle-income countries. In addition, this excess mortality does not differ substantially from that found in high-income countries. This suggests environmental factors occurring in low- and middle-income countries might not have a direct association with the excess mortality in the depressed elderly.

Keywords: depression; low- and middle-income countries; mortality.