LAUSR

OBJECTIVES This study investigated whether changes in loneliness and perceived social support predicted medical adherence in patients with coronary heart disease (CHD) over 12 months. Moreover, short-term and long-term buffering effects of social support on the association between loneliness and medical adherence were systematically examined. DESIGN A three-wave longitudinal study. METHODS Participants were 255 CHD patients with a mean age of 63 years. Medical adherence, loneliness, and perceived social support were assessed at baseline, 3 months, and 12 months. Hierarchical regression analyses were conducted to examine the influences of loneliness and social support as well as their changes on medical adherence over 12 months. Moderation analyses were performed to test buffering effects of baseline social support and its changes against loneliness and its changes, respectively. RESULTS Changes in loneliness significantly predicted medical adherence at 12 months (β = -.23, p = .001) but not at 3 months (β = -.10, p = .142). Changes in social support predicted medical adherence at both 3 (β = .23, p = .002) and 12 months (β = .26, p = .001). Social support concurrently buffered the adverse impact of loneliness on medical adherence (B = .29, SE = .12, p = .020) at baseline but did not at 3 or 12 months (Bs = -.21 to .40, SEs = .12 to .30, ps = .177 to .847). CONCLUSIONS Findings highlight the importance of monitoring loneliness and perceived social support continuously over time for CHD patients to promote medical adherence.