Weight gain post–heart transplantation is associated with an increased risk for allograft vasculopathy and rejection

OBJECTIVE: Obesity and overweight are associated with an increased risk for cardiovascular disease. Since fat mass (FM) and fat-free mass (FFM) both contribute to total body weight (TBW), we characterized the post–heart transplantation (HT) change in TBW and its implications for outcomes. METHODS: Post-HT changes in TBW, FM, and FFM were reviewed for 211 HT patients assessed during 1997–2017. Endpoints included cardiac allograft vasculopathy (CAV) and rejection. RESULTS: Median TBW increased by 7.3% at 1 year, with a significant rise in the obese category (28% vs. 13%, p < 0.001) and with FM versus FFM making the main contribution (23% vs. 3%, p < 0.001). When patients were divided according to median TBW change (“high” vs. “low”), Kaplan–Meier analysis showed that 10-year freedom from CAV (log-rank p < 0.005) and rejection (log-rank p < 0.01) was significantly higher for the “low” TBW change group. Consistently, multivariable analyses showed that the “high” group was independently associated with significant 3.5-fold and 4.2-fold increased risks for CAV (95% CI 1.4–8.7, p = 0.01) and rejection (95% CI 1.2–15.4, p = 0.03), respectively. CONCLUSIONS: Weight gain, contributed mostly by FM, is independently associated with an increased risk for CAV and rejection. Follow-up emphasis should be placed on weight gain and preventative measures.