Prevalence and associated factors of depression in Sri Lanka: a systematic review and meta-analysis

Epidemiological data on depression are required to inform policies and service planning in mental health in Sri Lanka. This review aimed to synthesise data from existing studies to calculate the pooled prevalence of depression in Sri Lanka, assess its variability across subgroups, and identify associated factors within each subgroup.

PubMed, Embase, PsycINFO, Science Direct, Google Scholar and local journals were searched to identify peer-reviewed studies reporting the prevalence of depression among non-clinical adult, young, older, and maternal populations in Sri Lanka. A meta-analysis was performed using a random-effects model to calculate pooled prevalence estimates. Subgroup, sensitivity and moderator analyses were performed. A qualitative synthesis of factors associated with depression was conducted.

A total of 33 studies representing a total of 52,778 participants were included. Overall, the pooled prevalence of depression was 19.4% [14.44-25.54%]. Among subpopulations, the highest prevalence was reported among young persons (39%); the rates in adults, older persons and maternal populations were 8.7%, 18.4% and 16.9%, respectively. Prevalence estimates were higher when based on screening instruments (21.2%) compared to diagnostic interviews (4.3%). A high degree of heterogeneity (I² = 99.2) was observed. A qualitative synthesis of factors associated with depression, including individual attributes and behaviours, socio-economic circumstances and broader environmental factors, is reported for each age group.

Approximately one-fifth of the population was detected to have depression. Notable variations in prevalence were observed across age groups. The heterogeneity of studies limits the inferences drawn from this review.