Impact of body weight on long-term survival after lung transplantation

Study objectives. The purpose of this study was to determine the impact of a pretransplantation determination of body mass index (BMI) on survival after lung transplantation. Design and patients: Univariate and multivariate survival analyses of a single institution database consisting of 85 patients who had undergone lung transplantations between March 1994 and October 1998. Setting: University of Florida Health Science Center. Results: Kaplan-Meier survival curves showed that patients who were obese (ie, BMI, greater than or equal to 30) at a pretransplantation assessment had a marked decrease in posttransplantation survival time (log rank, p < 0.05; Wilcoxon, p < 0.05). The final Cox regression model revealed that the most powerful predictors of mortality after lung transplantation were higher pretransplantation BMI and the development of obliterative bronchiolitis. Conclusions: Our results suggest that the posttransplantation risk for mortality is possibly three times greater for obese patients than for nonobese patients. Additional study is needed to identify the mechanisms for such higher risk in obese patients. Our data also suggest that transplantation centers should not routinely reject underweight patients (ie, BMI, < 18.5) or overweight patients (ie, BMI, 25 to 29.9) for lung transplantation listing solely on the basis of weight, as their outcomes may not be significantly different than patients with normal BMIs.