Impact of Functional Status on Survival After Coronary Artery Bypass Grafting in a Veteran Population

Abstract

Although functional impairment has been shown to be an adverse outcome of frailty, little is known of its effect on patients after cardiac operations. We aimed to assess the effect of limited functional status on long-term survival after coronary artery bypass grafting (CABG). We reviewed prospectively gathered data from 1,503 consecutive patients who underwent isolated CABG between 1997 and 2009. We compared the outcomes of 318 patients with limited functional status and 1,185 patients without any functional impairment. The mean follow-up period was 65 months (range, 1 to 157 months). We assessed the relationship between functional status impairment and long-term survival by Cox regression analysis adjusted for confounding factors. Functionally impaired patients were slightly older (63±9 vs 62±8 years, p=0.05) and had more risk factors for adverse outcomes than patients who were functionally unimpaired. After adjustment for potential confounding variables by multivariate logistic regression analysis, preoperative limited functional status was not an independent predictor (odds ratio [95% confidence interval]) of 30-day mortality (1.4 [0.3 to 5.8], p=0.67) or major adverse cardiac events (1.3 [0.5 to 3.3], p=0.71), nor was it predictive of reduced long-term survival (10-year hazard ratio 1.0 [0.7 to 1.4], p=0.85). Limited functional status was not an independent risk factor for early postoperative complications or death. Long-term survival in patients whose functional status was impaired before they underwent CABG was similar to that of patients who were functionally independent.