Preoperative obesity is associated with decreased survival after heart transplantation

It is difficult to assess candidacy of obese patients for heart transplantation because the effect of obesity before heart transplantation on posttransplantation outcome has not been examined. Therefore, the purpose of this study was to examine the impact of both preoperative weight and postoperative weight gain on outcome after heart transplantation.

The retrospective sample included 193 consecutive patients undergoing transplantation between March 1984 and June 1991 (mean age 47 +/- 14 years, 75% male). Data were gathered from retrospective chart review. Percent ideal body weight was calculated for each patient. Patients were divided into three groups based on pretransplantation percent ideal body weight: < 90% ideal body weight (n = 30), 90% to 110% ideal body weight (n = 79), and > 110% ideal body weight (n = 84). Chi-square, analysis of variance, Kaplan-Meier survival distributions, and the Cox Proportional Hazards Model were used for analyses.

Patients > 110% ideal body weight tended to have more coronary artery disease and higher serum triglyceride levels and significantly higher cholesterol levels than patients < 90% ideal body weight. After heart transplantation, no significant differences were found among the three pretransplantation percent ideal body weight groups regarding acute rejection, infection, and allograft arteriopathy. Survival was significantly worse among patients who were overweight before surgery (p = 0.018). A multivariate survival analysis showed that percent ideal body weight was an independent predictor of survival after heart transplantation (p = 0.046).

Despite a similar incidence of infection and rejection after heart transplantation among the three percent ideal body weight groups, obesity before heart transplantation is associated with significantly decreased survival after heart transplantation.