The impact of climate change on the mental health of the ageing population: a systematic review

Abstract

OBJECTIVES: The convergence of climate change and population ageing poses a global health challenge, especially in LMICs, where older adults face unique vulnerabilities. Evidence on mental/cognitive impacts is fragmented and geographically skewed, hindering policy. We systematically synthesised quantitative evidence on these impacts in older adults. METHOD: Following PRISMA/PROSPERO guidelines, we searched Scopus, EBSCOHost, ScienceDirect, and Web of Science (Jan 2000-June 2025) for studies linking climate exposures (e.g. thermal stress, disasters) to mental/cognitive outcomes in older adults (>60 years). Two reviewers extracted data and assessed bias. Findings were narratively synthesised due to heterogeneity. RESULTS: We included 28 quantitative studies. Thermal stress (heat/cold) was robustly linked to increased depressive symptoms. Acute disasters were consistently associated with higher psychological distress, anxiety, and PTSD. An emerging link between heat exposure and cognitive impairment has been identified, although some studies suggest that older adults exhibit greater psychological resilience post-disaster than younger cohorts. Key pathways (physical health, sleep, social support) were identified. Critically, the evidence is profoundly concentrated in East Asia (primarily China), with significant data gaps in Africa and South Asia. CONCLUSION: Climate change poses a significant threat to older adults' mental and cognitive health. The severe geographic research imbalance, neglecting low- and middle-income settings-especially sub-Saharan Africa and South Asia-represents a major global health failure. Future research and funding must prioritise these high-risk, low-evidence regions and shift towards the development and testing of interventions.