Exploring the silent epidemic: investigating the hidden burden of normal weight obesity in type 2 Diabetes Mellitus in India - a cross-sectional study.

Objective: This study aimed to determine the prevalence of Normal Weight Obesity (NWO) and evaluate its association with cardiometabolic risk factors among patients with Type 2 Diabetes Mellitus (T2DM) in Gujarat, India.

Methods: This cross-sectional study included 432 adults with T2DM attending a Non-Communicable Disease clinic. Anthropometric measurements, body composition analysis using bioelectrical impedance, and clinical parameters were assessed. NWO was defined as normal BMI (18.5-24.9 kg/m²) with high body fat percentage (≥ 25% for men, ≥ 32% for women). Cardiometabolic risk factors, including blood glucose, blood pressure, and lipid profile, were evaluated. Statistical analyses included descriptive statistics, correlation analysis, and multivariate logistic regression.

Results: The prevalence of NWO was 33% among the study population. Significant discordance was observed between BMI classification and body fat percentage, with 91% of males and 51.8% of females with normal BMI having obese levels of body fat. Individuals with NWO demonstrated higher cardiometabolic risk profiles compared to non-obese counterparts, including elevated random blood glucose levels (290 ± 110 mg/dL vs. 180 ± 80 mg/dL, p < 0.001), higher systolic (148.8 ± 25.4 mmHg vs. 122.5 ± 19.5 mmHg, p < 0.001) and diastolic blood pressure (98.5 ± 55.6 mmHg vs. 78.6 ± 36.6 mmHg, p < 0.001), and increased prevalence of hypertension (61% vs. 15%, p < 0.001). A moderate positive correlation was found between body fat percentage and random blood sugar levels (r = 0.504, p < 0.001). Multivariate analysis identified age, duration of diabetes, blood glucose levels, and blood pressure as independent factors associated with NWO.

Conclusion: The high prevalence of NWO and its significant association with adverse cardiometabolic risk factors in T2DM patients underscores the limitations of using BMI alone for obesity assessment. These findings highlight the need for incorporating body composition analysis in routine clinical practice to improve risk stratification and management strategies in T2DM patients, particularly in the Asian Indian population.