The Association Between Social Isolation and Medication Adherence Among Chinese Older Adults With Chronic Diseases: Serial Mediation of Social Support and Loneliness

Abstract Background Medication adherence is essential for chronic disease management among older adults. Previous studies have shown significant links among social isolation, social support, loneliness, and medication adherence, yet most were based on cross-sectional designs. Purpose We conducted a longitudinal cohort study among Chinese older adults with chronic diseases to explore the mediating effects of social support and loneliness in the association between social isolation and medication adherence. Methods This study followed a cohort of 797 older adults with chronic diseases in China from 2022 to 2023. The serial mediation model was examined via bootstrapping techniques to evaluate the mediating effect of social support and loneliness in the association between social isolation and medication adherence. Results From baseline to follow-up, there were significant decreases in social support (from 26.6 ± 6.2 to 23.5 ± 6.7) and medication adherence (from 6.7 ± 1.2 to 6.0 ± 1.5) and significant increases in social isolation (from 1.8 ± 1.3 to 2.5 ± 1.4) and loneliness (13.2 ± 4.1 to 23.5 ± 6.7), all with p < .001. A serial mediation model was confirmed, where social support and loneliness serially and partially mediated the association between social isolation and medication adherence (total effect c = −0.216, 95% CI = −0.296 to −0.136; direct effect cʹ = −0.094, 95% CI = −0.171 to −0.017; total indirect effect ab = −0.122, 95% CI = −0.179 to −0.070). Conclusions Our findings yield critical insights into the relationship between social isolation and medication adherence through various mediating mechanisms. These findings hold significant implications for devising psychosocial interventions to enhance medication adherence among older adults with chronic diseases, underscoring the pivotal role of bolstering social support and alleviating loneliness.