BMI-C como preditor de Diabetes Mellitus tipo 2 - Validação em duas coortes independentes do NHANES (2015-16 e 2017-18)

AbstractObjective: To validate BMI-C (Body Morphometric Index – Corrected) as a predictor of Type2 Diabetes (T2D) in two independent cohorts of the US population, and to compare itsperformance with that of traditional body mass index (BMI).Methods: Cross-sectional study using NHANES 2015-16 (N=6,321) and 2017-18 (N=6,015).BMI-C was calculated using the proprietary algorithm available at bmi-c.com, with inputs:waist circumference (cm), height (cm), weight (kg), age (years), and sex. T2D was definedby self-reported diagnosis, use of insulin or oral hypoglycemic agents, HbA1c ≥ 6.5%, orfasting glucose ≥ 126 mg/dL. ROC curves, age- and sex-adjusted logistic regression, andrelative risk by category were calculated. BMI was calculated as weight/height² forcomparison. The 95% CI of AUCs was estimated by bootstrap (2,000 resamples).Results: T2D prevalence was 15.0% (2015-16) and 13.3% (2017-18). BMI-C showed AUCof 0.738 (95% CI: 0.723–0.755) and 0.719 (95% CI: 0.702–0.736), respectively. BMI showedAUC of 0.687 (95% CI: 0.670–0.704) and 0.662 (95% CI: 0.642–0.681). The AUC differencewas +0.051 and +0.057, respectively. The optimal BMI-C cut-off was 1.32 and 1.29; theoptimal BMI cut-off was 26.7 and 27.8 kg/m². The age- and sex-adjusted odds ratio forBMI-C was 12.48 (95% CI: 7.85–19.86) and 18.58 (95% CI: 11.47–30.09). Thedose-response relationship was consistent across cohorts: T2D risk ranged from 2.1%(BMI-C 0.8–0.9) to 42.9% (BMI-C 1.8–1.9) in 2015-16, and from 0.0% to 33.0% in 2017-18.Conclusion: BMI-C is a robust and replicable predictor of T2D, with performanceconsistently superior to BMI across two independent cohorts. Its low cost and simplicitymake it viable for initial screening in primary care, complementing — not replacing —laboratory-based diagnostic tests.