Disease-Based Criteria vs BMI Level for Prioritization of Metabolic Surgery

BMI is widely used as a primary criterion for prioritizing candidates for metabolic surgery. However, it may not fully capture disease severity or mortality risks associated with comorbidities such as type 2 diabetes (T2D) and cardiovascular disease (CVD). This study aimed to assess whether BMI accurately reflects disease burden and risk in patients undergoing metabolic surgery.

A retrospective audit included 723 adult candidates for primary metabolic surgery at a tertiary care center between January 2014 and December 2022. Patients undergoing revisional surgeries were excluded. Clinical data, including demographics, comorbidities, and disease severity indicators (e.g., ASA score, Charlson Comorbidity Index [CCI], medication usage, and estimated 10-year survival), were analyzed. Patients were grouped by BMI (< or ≥ 50 kg/m²), T2D, and CVD status for comparison.

Prevalence rates for T2D, BMI ≥ 50 kg/m², and CVD were 41.6%, 37.3%, and 16.2%, respectively. Patients with BMI ≥ 50 kg/m² were generally younger, had fewer comorbidities, lower CVD prevalence, and better estimated 10-year survival than those with BMI < 50 kg/m². In contrast, patients with T2D and CVD had significantly higher ASA and CCI scores, greater medication usage, and reduced 10-year survival (p < 0.001 for T2D; p < 0.01 for CVD).

Higher BMI levels do not reflect greater disease burden and mortality risk among candidates for bariatric/metabolic surgery. These findings do not support the use of high BMI-based thresholds (e.g., ≥ 50 kg/m²) as criteria for expedited access. Clinically relevant measures of baseline disease burden should be used to determine the urgency of access to surgical treatment of obesity and T2D.