Survival Outcomes of Lung Recipients with Body Mass Index ≥35 kg/m2

Abstract

<h3>Purpose</h3> Transplant consensus statements identify advanced lung disease patients with a body mass index (BMI) ≥35 kg/m² as unlikely candidates for lung transplantation (LT); however, such patients with an otherwise acceptable risk profile tend to cluster in large volume centers. We reviewed our experience with long-term survival of overweight and obese lung transplant recipients (LTRs). <h3>Methods</h3> Of 1004 LTRs from 2007-2021, patients were excluded for BMI <25 kg/m² (n=410), retransplant (n=30), or missing data (n=3); remaining LTRs were divided by listing BMI: overweight (OWT, 25-29.9 kg/m²), obesity class-I (C-I, 30-34.9 kg/m²), and obesity class-II (C-II, ≥35 kg/m²). The primary endpoint was survival. <h3>Results</h3> In total, 561 LTRs were divided into OWT (n=337), C-I (n=208), and C-II (n=16). Subjects in C-II were younger than those in OWT (p<0.01), tended to be the sickest (median LAS 40 [37, 56]), and underwent LT fairly quickly after listing (median 19 [9, 45] days). Of note, the median BMI of C-II patients (35.9 [35, 36] kg/m²) was at the low end of the class. Length of stay for LT was comparable between groups. Compared to OWT, the risk of death at 60 days after LT was 6-fold higher in C-I and 11-fold higher in C-II [p=0.03 and p<0.01, respectively]. At 60 days after LT, OWT had the highest probability of survival followed by C-I and C-II [99.4% vs 96.6% vs 93.8%, respectively, p=0.02]; however, there was no difference between C-I and C-II. Furthermore, survival at 1 and 5 years was similar between groups (Figure 1). <h3>Conclusion</h3> Carefully selected candidates with a BMI slightly higher than 35 kg/m², no other contraindications to LT, and rapidly decompensating lung disease were a small proportion of the overall cohort with an unrealistic amount of time to lose weight. Despite higher perioperative mortality, LTRs with a listing BMI ≥35 kg/m² may have near-equivalent long-term survival as those with BMI 30-34.9 kg/m². In otherwise strong candidates, severe obesity should not be a significant predictor of long-term mortality. Further validation is needed.