How using body mass index cutoffs to determine eligibility for total shoulder arthroplasty affects health care...

The prevalence of obesity in the United States is continuously rising and is associated with increased morbidity, mortality, and health care costs. Body mass index (BMI) has been used as a risk stratification and counseling tool for patients undergoing total joint arthroplasty in an effort to focus on outcome-driven care. Although the use of BMI cutoffs may have benefits in minimizing complications when selecting patients for total shoulder arthroplasty (TSA), it may impact access to care for some patient populations and further increase disparities. The purpose of this study is to determine the implications of using BMI cutoffs on the eligibility for TSA among different ethnic and gender patient populations.

The American College of Surgeons National Surgical Quality Improvement Program database was queried to identify 20,872 patients who underwent anatomic and reverse TSA between 2015 and 2019. Patient demographics, including age, sex, race and ethnicity, and BMI, were compared between eligible and ineligible patients based on BMI for 5 cutoff values: 30, 35, 40, 45, and 50 kg/m².

Of the total patient population studied, the mean age was 69 years, 55% were female, and the mean BMI was 31 kg/m². For all BMI subgroups, there were more ineligible than eligible patients who were female or Black (P < .001). The relative rate of eligibility for Black patients was lower in each BMI cutoff group, whereas the relative rate of eligibility for White and Asian patients was higher for each group. There were more eligible than ineligible Asian patients for BMI cutoffs of 30 and 35 kg/m² (both P < .001), and there were no differences in eligibility and ineligibility in Hispanic patients (P > .05). Furthermore, White patients were more eligible than ineligible for all BMI cutoff groups (P < .001).

Enforcing BMI cutoffs for access to TSA may limit the procedure for female or Black patients for all BMI cutoffs, thus furthering the health care disparities these populations already face. However, there are more eligible than ineligible White patients for all BMI cutoff groups, which indicates a disparity in the access to TSA based on sex and race. Physicians may inadvertently increase health care disparities observed in TSA if they use BMI as the sole risk stratification tool for patients, even though BMI has been known to increase complications after TSA. Moreover, orthopedic surgeons should only use BMI as one of many factors in a more holistic process when determining if a patient should undergo TSA.