What role does social activity play in the relationship between hearing loss and cognitive decline or mental health in older adults: A systematic review and meta-analysis

OBJECTIVE: Hearing loss is a global public health concern among older adults, associated with cognitive decline and other mental health disorders. Social activity has been proposed as a potential pathway linking hearing loss and mental outcomes. This systematic review aimed to clarify the dual mediating and moderating roles of social activity in the links between hearing loss and mental health outcomes. METHODS: We searched five databases up to April 23, 2025, for empirical studies examining the role of social activity in the relationship between hearing loss and mental health. Data were synthesized using random-effects meta-analysis or best-evidence synthesis. RESULTS: Nineteen studies (11 longitudinal, 8 cross-sectional) were included, covering cognitive function (n = 12), depressive symptoms (n = 4), and positive emotional outcomes (n = 3). Meta-analysis showed a small but significant mediating effect of social activity on the hearing loss-cognitive decline link (estimate = -0.004, 95 % CI: -0.007 to -0.001), and a significant moderating effect (estimate = 0.087, 95 % CI: 0.050 to 0.124), with stronger negative effects among those with lower social activity. Best-evidence synthesis provided moderate support for mediation with depressive symptoms and positive emotional outcomes, and limited evidence for a moderating effect on depressive symptoms. CONCLUSION: This review highlights the dual role of social activity in mediating and moderating the association between hearing loss and mental health in older adults. These findings underscore the importance of promoting social activity as a potential target for interventions. Further research is needed to validate these findings and identify effective strategies to enhance social activity.