Relationship among Fatness, Blood Lipids, and Insulin Resistance in Pakistani Children

Observations on associations between fatness and metabolic risks among South-East Asian adults have resulted in devising lower thresholds of body mass index (BMI) for them. Metabolic abnormalities, including type 2 diabetes, are now also appearing in children and are associated with obesity. There has not been much work done to identify indicators of metabolic risks among South Asian children. This study was undertaken to observe the relationship among fatness, blood lipids, and insulin resistance in Pakistani children. Fatness, lipids, and insulin resistance were assessed in 92 middle-class Pakistani school children aged 8-10 years. Height, weight, waist, hips, mid-arm circumference, and triceps skin-fold, measured in school, were used for calculating various indicators of fatness, i.e. BMI, waist hip ratio (WHR), and arm-fat percentage. Fasting blood samples were analyzed for total lipids, triglycerides (TG), total cholesterol (TC), high density lipoprotein (HDL), low density lipoprotein (LDL), glucose and insulin levels. Homeostasis model assessment (HOMA) index was calculated to assess insulin resistance. Two separate multiple regression models of various risk indicators (family history, sex, BMI, WHR, arm-fat percentage) showed that only arm-fat percentage had a significant positive association both with insulin levels (b=2.04, p= 0.044) andLDL (b= 2.11, p= 0.037). Only five children were overweight(BMI-for-age>85th percentile according to National Center for Health Statistics 2000 reference). Neither overweight children nor those who were in the uppermost tercile of BMI-for-age differed significantly from other children in terms of presence of higher-than-desirable values of lipids or insulin. However, compared to those in the lowest tercile, children who were in the uppermost tercile of arm-fat percentage had a significantly higher frequency of high blood cholesterol (40% vs 67%, p=0.027), high LDL (33.3% vs 61.3%, p=0.026), and markedly higher proportion above average insulin levels (16.7% vs 35.5%, p=0.083). Arm-fat percentage could be developed as a practical tool for determining the risk status of children. However, further cross-sectional assessments are needed to ascertain accurate relationships among arm-fat percentage, lipid profiles, and insulin resistance in larger and varied groups of children.

Keywords
Obesity; Lipids; Insulin resistance; Anthropometry; Child; HOMA; Pakistan