“…The van Walraven modification of the Elixhauser Comorbidity Index was utilized to evaluate the burden of chronic diseases [ 16 ]. Patients were stratified by obesity class using ICD-10 codes and World Health Organization classification, into class 1 (BMI = 30.0–34.9), class 2 (BMI = 35.0–39.9), and class 3 (BMI ≥ 40.0) (Supplemental Table 1) [ 17 , 18 ]. To facilitate comparison, patients with class 3 obesity comprised the Class 3 cohort, with all others classified as Class 1–2 .…”