Aim To investigate the relationship of Body Mass Index (BMI) percentile cut off with Homeostasis Model Assessment-Insulin Resistance (HOMA-IR), a surrogate marker for insulin resistance in obese, overweight and non-obese adolescents.
Study Design A cross-sectional analysis of 100 adolescents (divided into 50 overweight/obese and an equal number of non-obese) was performed on non-diabetic 11 to 18 year old school going adolescents. The main outcome measure of insulin resistance was calculated as HOMA-IR (greater than 3.16). Obesity was defined using the BMI criteria. BMI greater than or equal to 95th percentile for age and sex was defined as obese, overweight was defined as BMI greater than or equal to 85thpercentile and non-obese were defined as BMI less than 84.9th percentile. All adolescents were subjected to analysis of anthropometric parameters that included weight, height and BMI (body mass index). Biochemical parameters, namely venous plasma glucose (fasting) and venous plasma insulin (fasting) were included for insulin resistance calculation by HOMAIR.
Results Having a BMI of greater than or equal to 85th percentilewas associated with high HOMA-IR levels. As the BMI percentiles increased, the HOMA-IR levels also increased. Prevalence of insulin resistance for a BMI percentile of less than 84.9 was nil. Prevalence of insulin resistance for a BMI percentile of 85–94.9 was 25%. Prevalence of insulin resistance for BMI of greater than or equal to 95th percentile was 55%.
Conclusion Insulin resistance is highly prevalent in obese and overweight adolescents as compared to that in non-obese adolescents. Early primordial and primary prevention can thus alleviate the burden of future cardiometabolic disorders.