High prevalence of metabolic obesity in India: The ICMR-INDIAB national study (ICMR-INDIAB-23)

Background & objectives While obesity usually produces cardio-metabolic dysfunction, some obese individuals are metabolically healthy, and conversely, some nonobese individuals have significant metabolic dysfunction. This study aims to assess the national prevalence of various obesity subtypes and their association with type 2 diabetes (T2D), coronary artery disease (CAD), and chronic kidney disease (CKD) in the Indian Council of Medical Research-India Diabetes (ICMR-INDIAB) study. Methods The ICMR-INDIAB study is a nationally representative cross-sectional survey of 1,13,043 individuals aged ≥20 yr from urban and rural areas across 31 Indian States and Union Territories. In every fifth individual (n=19,370), venous blood glucose and lipids were measured. A body mass index (BMI) ≥25 kg/m2 was defined as being obese, and metabolic obesity was diagnosed if two risk factors, out of the following: high waist circumference, high blood pressure, elevated blood glucose, raised serum triglycerides, or low HDL cholesterol, were present. Four subgroups were identified: Metabolically Healthy Non-Obese (MHNO), Metabolically Healthy Obese (MHO), Metabolically Obese Non-Obese (MONO), and Metabolically Obese Obese (MOO). Results The prevalence of various obesity subtypes was as follows: MONO: 43.3 per cent [95% confidence interval (CI): 42.6-44%], MOO: 28.3 per cent (27.7-28.9%), MHNO: 26.6 per cent (26-27.2%), and MHO: 1.8 per cent (1.6-2%). MONO was more prevalent in rural areas [Rural vs. Urban: MONO: 46 per cent (45-46.9%) vs. 39.6 per cent (37.8-41.3%), P<0.001]. MOO showed the highest risk for T2D and CAD, while MONO showed the highest risk of CKD, especially among females. Interpretation & conclusions Individuals with MONO have a distinct phenotype with adverse metabolic consequences, highlighting the need to shift from body weight-focused approaches to broader strategies to identify and tackle non-communicable diseases (NCDs) in India.