The Longitudinal Stress-Buffer role of informal and formal support in later life

Introduction: We investigated whether type of instrumental support received – informal only, formal only or both informal and formal support – differentially buffered the harmful relationships between disability and depressive symptoms and life satisfaction over an eight-year period. The stress-buffer age-variation hypothesis (i.e., that the stressbuffer effects of social support strengthen in later life with increasing age) was also examined. Methods: We used multilevel modelling with three waves of data from a population-based sample of communitydwelling older adults (N=1961 at Wave 1). Time-invariant predictors were sociodemographic characteristics; social networks with children, relative and friends; and physical health variables. Time-varying predictors included marital status, cognitive status, functional limitations and type of support received. Dependent variables were depressive symptoms and life satisfaction. Results: Relative to no support, receipt of formal support in isolation moderated the negative association between increasing functional limitations and life satisfaction. Similarly, receipt of informal support only was associated with a weaker relationship between increasing functional limitations and depressive symptoms. Analyses also revealed that this second moderating effect strengthened with age. Finally, receipt of support was directly associated with greater depressive symptoms and lower life satisfaction, but only for individuals with few increases in functional limitations over time. Conclusions: Our findings highlight the complexity in the relationships between disability, received support and mental health. They indicate that instrumental support from both informal and formal sources has the potential to buffer the harmful effects of disability on mental health, and that these protective effects may strengthen in later life with increasing age.