The Hidden Burden of Climate Change: A Systematic Review of Mental Health Outcomes in Sub-Saharan Africa

Abstract

Background: Climate change is increasingly recognised as a major threat to mental health globally, particularly in vulnerable regions such as Sub-Saharan Africa (Bressan, Duranovic, Monasterolo, & Battiston). Rising temperatures, prolonged droughts, flooding, and other extreme weather events disrupt livelihoods, food and water security, and social systems, thereby increasing the risk of mental health disorders among affected populations. Despite growing evidence, the mental health consequences of climate change in SSA remain inadequately synthesised. Objective: This systematic review aimed to explore the effects of climate change on the mental health of people living in Sub-Saharan Africa, determine the prevalence of climate-related mental disorders, and identify regional differences in mental health outcomes associated with climate change events. Methods: The review followed a protocol registered on PROSPERO (CRD42024602491) and adhered to PRISMA guidelines. Peer-reviewed observational studies published between January 2015 and December 2025 were retrieved from Scopus, Science Direct, Embase, PubMed, and African Index Medicus. Eligible studies assessed the relationship between climate change-related exposures, including drought, flooding, extreme temperatures, and general climate variability, and mental health outcomes among populations in SSA. Data extraction and quality appraisal were independently conducted by multiple reviewers using the OHAT/HATs risk-of-bias tools and the GRADE framework. Narrative synthesis and heterogeneity analyses were performed using R version 4.3.6. Results: Ten studies involving 22,858 participants from Kenya, Nigeria, Tanzania, and South Africa met the inclusion criteria. Most studies were cross-sectional (n=9), with one longitudinal study. Climate change exposures included drought and reduced rainfall (n=4), flooding (n=1), extreme environmental temperatures (n=1), and general climate change (n=4). Reported mental health outcomes included depression, anxiety, climate anxiety, psychological distress, PTSD, substance use disorders, and suicidal ideation. Drought and reduced rainfall were consistently associated with increased anxiety, depressive symptoms, psychological distress, and suicidal ideation, particularly among women, youths, and smallholder farmers. Flood exposure was associated with elevated emotional distress, anxiety, depression, and PTSD among women living in vulnerable communities. General climate change concerns contributed significantly to climate anxiety, depression, stress, and suicidality among adolescents and young adults. High heterogeneity across studies limited the feasibility of quantitative meta-analysis. Conclusion: Climate change events substantially affect mental health in Sub-Saharan Africa, with vulnerable populations such as women, youths, rural communities, and low-income households disproportionately affected. Droughts, flooding, food insecurity, and climate-related uncertainty contribute to increased prevalence of anxiety, depression, PTSD, psychological distress, and suicidal ideation. However, limited longitudinal evidence and substantial methodological heterogeneity highlight the need for more robust studies to inform targeted mental health and climate adaptation policies in SSA.