Body Mass Index (BMI) Cutoffs and Racial, Ethnic, Sex, or Age Disparities in Patients Treated With Total Ankle Arthroplasty

Abstract

Background: The rising prevalence of obesity among American adults has disproportionately affected Black adults and women. Furthermore, body mass index (BMI) has historically been used as a relative contraindication to many total joint arthroplasty (TJA) procedures, including total ankle arthroplasty. The purpose of this study was to investigate potential disparities in patient eligibility for total ankle arthroplasty based on race, ethnicity, sex, and age by applying commonly used BMI cutoffs to the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database. Methods: Patients in the ACS-NSQIP database who underwent TAA from 2011 to 2020 were retrospectively reviewed in a cross-sectional analysis. BMI cutoffs of <50, <45, <40, and <35 were then applied. The eligibility rate for TAA was examined for each BMI cutoff, and findings were stratified by race, ethnicity, sex, and age. Independent t tests, chi-squared tests, and Fisher exact tests were performed to compare differences at an α = 0.05. Results: A total of 1215 of 1865 TAA patients (65.1%) were included after applying the exclusion criteria. Black patients had disproportionately lower rates of eligibility at the most stringent BMI cutoff of <35 ( P = .004). Hispanic patients had generally lower rates of eligibility across all BMI cutoffs. In contrast, Asian American and Pacific Islander patients had higher rates of eligibility at the BMI cutoffs of <35 ( P = .033) and <40 ( P = .039), and White non-Hispanic patients had higher rates of eligibility across all BMI cutoffs. Females had lower eligibility rates across all BMI cutoffs. Ineligible patients were also younger compared to eligible patients across all BMI cutoffs. Conclusion: Stringent BMI cutoffs may disproportionately disqualify Black, female, and younger patients from receiving total ankle arthroplasty. Level of Evidence: Level III, retrospective cross-sectional study.