Social prescribing for anxiety and depression in older adults: mechanistic pathways, implementation requirements, and limitations of current evidence.

Population ageing and the rising burden of multimorbidity require late-life anxiety and depression to be addressed beyond symptom control. Loneliness, social isolation, restricted activity, and loss of meaningful roles frequently interact with physical illness and functional decline; however, these determinants are not readily modified through conventional clinical care alone. Social prescribing offers a range of supported pathways through which health and care professionals connect individuals with non-clinical community resources, ranging from light-touch referrals to more holistic, relationally supported models. This narrative review used a structured literature search and an explicit evidence framework to distinguish between direct evaluations of social prescribing services, pathway-level evidence on constituent activities and mechanisms, and implementation evidence concerning referral, connector support, and community capacity. Current findings suggest the potential benefits for loneliness, social participation, quality of life, and selected depressive outcomes through strengthened social connections, behavioural activation, physical activity, engagement with nature and culture, and the restoration of valued social identities. Nevertheless, high-quality trials specifically enrolling older adults with diagnosed anxiety or depressive disorders remain scarce. Definitions of social prescribing, intervention intensity, comparators, and outcome measures vary substantially, while several proposed mechanisms are supported by indirect evidence rather than formal mediation analyses. Effectiveness, therefore, depends not only on the activity offered but also on appropriate risk stratification, shared decision-making, sufficient relational support when required, accessible community resources, and closed-loop evaluation. Future research should use complex intervention and implementation science frameworks to identify appropriate populations, core and adaptable components, causal mediators, cost-effectiveness, and equitable models that can be embedded within local primary care and ageing service systems.