Informal unpaid caregivers provide most of the world's care needs, experiencing numerous health and wealth penalties as a result. As the COVID-19 pandemic has highlighted, informal care is highly gendered. Longitudinal evidence is needed to assess the causal effect of caregiving on mental health. This review addresses a gap by summarising and appraising the longitudinal evidence examining the association between unpaid caregiving and mental health among working age adults in high-income Organisation for Economic Co-operation and Development (OECD) countries and examining gender differences.
Six databases were searched (Medline, PsycInfo, EMBASE, Scopus, Web of Science, Econlit) from Jan 1, 2000 to April 1, 2022. Population-based, peer-reviewed quantitative studies using any observational design were included. Population of interest was working age adults. Exposure was any unpaid caregiving, and studies must have had a non-caregiving comparator for inclusion. Mental health outcomes (depression, anxiety, psychological distress/wellbeing) were measurable by validated self-report tools or professional diagnosis. Screening, data extraction and quality assessment (ROBINS-E) were conducted by two reviewers. The study was prospectively registered with PROSPERO (CRD42022312401).
Of the 4536 records screened; 13 eligible studies (133,426 participants) were included. Overall quality of evidence was moderate. Significant between-study heterogeneity precluded meta-analysis, so albatross and effect-direction plots complement the narrative synthesis. Results indicate a negative association between informal unpaid care and mental health in adults of working age. Importantly, all included studies were longitudinal in design. Where studies were stratified by gender, caregiving had a consistently negative impact on the mental health of women. Few studies examined men but revealed a negative effect where an association was found.