Cardiometabolic risk factors in young Indian men and their association with parameters of insulin resistance and beta-cell function

BACKGROUND: There is an unmet need to evaluate the burden of cardiometabolic risk factors in young South Asian adults, who are not preselected for glycaemia. AIM: To evaluate young North Indian men (aged 20-50 years) for burden of cardiometabolic risk factors, in relation to parameters of homeostatic model assessment for insulin resistance (HOMA-IR) and beta-cell function (oral disposition index [oDI]). METHODS: Study participants were invited in a fasting state. Sociodemographic, anthropometric, and medical data were collected, and 75 g oral glucose tolerance test was performed with serum insulin and plasma glucose estimation at 0, 30, and 120 min. Participants were divided into quartiles for HOMA-IR and oDI (category 1: Best HOMA-IR/oDI quartile; category 3: Worst HOMA-IR/oDI quartile) and composite HOMA-IR/oDI phenotypes (phenotype 1: Best quartile for both HOMA-IR and oDI; phenotype 4: Worst quartile for both HOMA-IR and oDI) were derived. RESULTS: We evaluated a total of 635 men at a mean (± SD) age of 33.9 ± 5.1 years and body mass index of 26.0 ± 3.9 kg/m(2). Diabetes and prediabetes were present in 34 (5.4%) and 297 (46.8%) participants, respectively. Overweight/obesity, metabolic syndrome, and hypertension were present in 388 (61.1%), 258 (40.6%), and 123 (19.4%) participants, respectively. The prevalence of dysglycaemia, metabolic syndrome, and hypertension was significantly higher in participants belonging to the worst HOMA-IR and oDI quartiles, either alone (category 3 vs 1) or in combination (phenotype 4 vs 1). The adjusted odds ratios for dysglycaemia (6.5 to 7.0-fold), hypertension (2.9 to 3.6-fold), and metabolic syndrome (4.0 to 12.2-fold) were significantly higher in individuals in the worst quartile of HOMA-IR and oDI (category 3), compared to those in the best quartile (category 1). The adjusted odds ratios further increased to 21.1, 5.6, and 13.7, respectively, in individuals with the worst, compared to the best composite HOMA-IR/oDI phenotypes (phenotype 4 vs 1). CONCLUSION: The burden of cardiometabolic risk factors is high among young Asian Indian men. Our findings highlight the importance of using parameters of insulin resistance and beta-cell function in phenotyping individuals for cardiometabolic risk.