Social support as a predictor of participation in cardiac rehabilitation after coronary artery bypass graft surgery.

Abstract

Cardiac rehabilitation promotes recovery and enhances quality of life after a coronary artery bypass graft (CABG), but participation in such rehabilitation is low. The role of social support in promoting participation has been suggested by prior studies, but is not clearly defined. The purpose of this study was to investigate the role of social support as an independent predictor of participation in cardiac rehabilitation. This study examined 944 patients who underwent first isolated CABG between May 1999 and February 2001, then were followed for 6 months after surgery. Social support before CABG and 6 weeks after CABG was assessed using the Enhancing Recovery in Coronary Heart Disease (ENRICHD) Social Support Inventory (ESSI) and evaluated for its association with participation in cardiac rehabilitation. Of 944 patients, 524 (56%) reported participation in rehabilitation. The participants were younger, better educated, more often employed, and less financially strained. The participants also had a lower prevalence of cardiovascular disease risk factors and better physical function. According to unadjusted analysis, the patients with low social support (ESSI </= 22) before surgery were less likely to participate in rehabilitation than the other patients (52% vs 59%; risk ratio [RR], 0.89; 95% confidence interval [CI], 0.78-0.99). However, adjustment for demographic factors, medical history, cardiovascular disease risk factors, physical and psychological function, and hospital complications attenuated this association (adjusted RR, 0.92; 95% CI, 0.78-1.07). A low ESSI score measured 6 weeks after CABG similarly did not significantly affect participation in rehabilitation (adjusted RR, 0.96; 95% CI, 0.81-1.11). Contrary to what is believed generally, social support may not be a strong determinant of participation in rehabilitation after CABG. Correlates of social support such as gender, socioeconomic status, and comorbidity burden may have a more important role in cardiac rehabilitation participation than social support itself. When marital status was examined as a main predictive variable, the analyses yielded similar results (unadjusted RR, 0.72; 95% CI, 0.58-0.86; RR adjusted for the same covariates, 0.80; 95% CI, 0.60-1.02).