ボディマス指数、併存疾患、および新しいランセット肥満定義：形成外科および再建外科におけるリスク分析への影響

The Lancet Diabetes and Endocrinology Commission proposed a new definition of obesity that de-emphasizes body mass index (BMI) in favor of adiposity-related comorbidities. Our study evaluates the relevance of this paradigm shift to Plastic and Reconstructive Surgery (PRS) by analyzing the effects of BMI and adiposity-related comorbidities on 30-day complication rates.

The TriNetX health database was queried for patients undergoing PRS procedures. Patients were stratified by BMI categories and presence/absence of adiposity-related comorbidities. Cox regression analyses determined hazard ratios (HR) for 30-day complications with subset analyses performed by procedural complexity.

Among 957,985 patients, those with BMIs 25-39.9 and comorbidities (HR 1.05, p<0.001) or BMIs ≥40 (HR 1.40, p<0.0001) had significantly higher complication risks compared to normal-weight patients. Without comorbidities, patients with BMIs 25-29.9 had a lower risk (HR 0.83, p<0.0001), while those with BMIs 30-34.9 showed similar risk (HR 0.99, p=0.62) to normal-weight patients. An inflection point occurred at BMIs above 35, where complication risk increased even without comorbidities. Subset analysis revealed that BMI effects were most pronounced in body contouring procedures, with patients having BMIs ≥25 showing significantly increased risk, regardless of comorbidity status.

These findings partially support this new definition in the context of PRS. For patients with BMIs of 25-34.9 without comorbidities, weight loss may not change surgical risk. Comprehensive assessment of comorbidities should be considered for patients with BMIs 25-34.9, while weight loss or other risk mitigation strategies such as GLP-1 agonists may be recommended for patients with BMIs ≥35.