Social Capital and Depression: A Systematic Review

Background: Previous research has brought forth contradicting evidence on the association between social capital and depression. We reviewed the published literature to examine the present evidence of the association between social capital and depression. Methods: In this systematic review, we searched PubMed, Scopus, Web of Science, ProQuest, CINAHL and APA databases for studies. Search terms included “social capital” and variations of the term “depression”. Inclusion criteria included Finnish, Swedish or English language, and only scientific literature such as research and journal articles, and scientific publications. Articles not specifying and measuring depressive symptoms as an outcome variable were excluded. Articles where the outcome variable was a combination of different mental health outcomes which did not allow for the observation of only depressive symptoms were also excluded. Articles were appraised using the Covidence software, thus allowing for the two authors to appraise articles blindly. Findings: Originally 2487 studies were identified, which were reduced to 1224 after the duplicates were removed. 1096 studies were found irrelevant, and 128 studies were assessed for eligibility through a full-text review. In the end, 40 studies were found to be eligible for this review. Risk of bias assessment was conducted using the Cochrane bias analysis, which indicated no risk of bias in the articles included in the review. Interpretation: Various research highlighted an inverse association between social capital and depression. However, the generalisability of the results is limited, as there were variations between the aspects of social capital measured between studies. If causal association is found, it would interventions focusing on the prevention of depressive disorder through enhancing individuals’ social capital from early on. Depression is a major health burden globally and thus, focus should be on prevention of depression, rather than its treatment.Funding Information: The author Johanna Kemppainen is employed by Oulu University Hospital. The employee has had no part in any part of the article (writing, data collection, data analysis etc.) The co-author Markku Timonen is employed by the University of Oulu. The university had no part in any part of the article (writing, data collection, data analysis etc.) No other funding has been provided for this article. Declaration of Interests: There are no conflicting interests.