Background: The apparent protective effect of high body mass index on postoperative outcomes, termed the "obesity paradox," has been postulated to reflect the relative frailty of patients without obesity. We wanted to examine the independent association between body mass index and outcomes after anatomic lung resection.
Methods: All adults undergoing elective lung resection for cancer were identified in the 2012-2020 National Surgical Quality Improvement Program. The modified Frailty Index quantified degree of patient frailty. Malnutrition was defined as a preoperative serum albumin <3.5g/dL. Multivariable regressions were used to examine the independent association of body mass index and major adverse events, analyzed as a composite of 30-day mortality, postoperative complications, and unplanned reoperation.
Results: Of an estimated 20,099 patients meeting study criteria, 6,424 (32.0%) had obesity. Relative to others, patients with obesity were significantly younger (49.3 vs 50.3 years), more commonly White (78.1 vs 74.9%), and more frequently frail (modified Frailty Index >1: 35.7 vs 22.5%, all P < .001). There was no significant difference in malnutrition rates (7.6 vs 8.4%, P = .05) or extent of resection between groups. After adjustment, obesity was associated with decreased odds of major adverse events (adjusted odds ratio 0.86, 95% confidence interval 0.78-0.94).
Conclusion: The present findings uphold the canonical obesity paradox in anatomic lung resection, despite adjustment for frailty and malnutrition. Further studies are warranted to characterize the nature of this association; however, our results may inform efforts to optimize risk stratification and patient selection for surgical intervention.
Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.