Abstract 11065: Paradoxical Impact of Overweightness on Mortality in Lung Transplantation
Background: Prognostic value of body mass index (BMI) and cardiorespiratory fitness (CRF) has been described extensively in various populations. The objective of this study was to examine impact of BMI and CRF on all-cause mortality in isolated lung transplant recipients.
Methods: Consecutive isolated lung transplant recipients from 2008 to 2013 were identified. Pre-transplant cardio-metabolic risk factors were collected. The cohort was categorized using BMI into normal (BMI 18.5-24.9 kg/m2), underweight (BMI < 18.5 kg/m2), overweight (BMI 25.0-29.9 kg/m2) and obese (BMI ≥ 30 kg/m2). Fit patient was defined as those who had pre-transplant six-minute-walk distance > 300 m.
Results: The study comprised of 324 patients with mean age of 57 ± 13 years. Fifty eight percent were male. Primary lung pathologies were 26.9% obstructive, 2.5% vascular, 6.5% cystic fibrosis and 64.2% restrictive lung diseases. Pertinent cardio-metabolic risk factors included 36.7% normal weight, 9.9% underweight, 33.6% overweight, 19.8% obese, 21.9% unfit, 13.9% coronary artery disease, 55.6% hypertension, 29.6% diabetes mellitus, 42.3% hyperlipidemia, 42.9% smoking history. Annualized mortality rate stratified by BMI exhibited J-shaped distribution with lowest mortality in overweight group (p 0.005). Kaplan Meier analysis correspondingly showed highest survival in overweight strata (p 0.006). In subgroup analysis by CRF, paradoxical impact of overweightness on mortality was diminished in fit patients (p>0.05) but not in those who were unfit (p<0.05) as shown in figure 1.
Conclusion: In our lung transplant cohort, BMI and mortality had J-shaped relationship with highest survival in overweight group. This paradoxical impact was diminished in patients who were fit. Our findings extend the paradigm of obesity paradox into lung transplantation arena.
Author Disclosures: K. Chaikriangkrai: None. H. Jhun: None. S. Jyothula: None.
- © 2014 by American Heart Association, Inc.