Obesity And Weight Gain Following Heart Transplantation

Abstract

Purpose: Obesity is a common co-morbidity in both heart failure and heart transplantation. Our purpose was to examine changes in body weight and body mass index (BMI) over 3 years post-transplant and assess for correlation with right heart hemodynamics. Methods: We identified 257 consecutive patients (mean age 52 ± 13 years; 78% male) who underwent heart transplantation at our institution from 2007 through December 2019. Re-transplants and heart/lung transplant were excluded. Height, weight, and BMI were recorded at the time of transplant and at 1-year and at 3-year post-transplant. Patients were characterized according to BMI: underweight (BMI < 18.5 kg/m2), normal (18.5 to < 25 kg/m2), overweight (25 to < 30 kg/m2), and obese (> 30 kg/m2). Right heart catheterization hemodynamics were analyzed at 3 years post-transplant. Data was available for 237 patients at 1 year (93% survival; 18 deaths) and 211 patients at 3 years (82% survival; 38 deaths, 5 transferred to another center, and 3 lost to follow-up). Results: Changes in body weight and BMI are shown in the table. There was a modest yet significant increase in weight and BMI at both 1-year and 3-year post-transplant (*p < 0.05 1-year and 3-year versus transplant). In the first year post-transplant, 53 patients experienced 10 kg of weight gain, whereas only 22 patients had 10 kg of weight loss. The proportion of patients who were overweight or obese was 74% at 1-year and 80% at 3-year. At 3 years post-transplant, obese patients had significantly higher right atrial pressure (9 ± 4 versus 6 ± 4 mm Hg), mean pulmonary artery pressure (24 ± 5 versus 19 ± 5 mm Hg), and pulmonary capillary wedge pressure (15 ± 4 versus 11 ± 4 mm Hg; p < 0.01 for all) versus overweight/normal patients. Conclusion: In our patient population, weight gain was common post-transplant with 80% of patients being either overweight or obese by BMI criteria 3-years post-transplantation. Obesity was associated with elevation in filling pressures and mean pulmonary artery pressure.