RESUMEN
Objectives: To identify important factors (linked to lifestyle, eating and sedentary behaviors) relating to waist circumference among urban South Indian children aged 3 to 16 years. Design: Cross sectional. Setting: Urban schools of Bangalore, from August 2008 to January 2010. Participants: 8444 children; 4707 children aged 3-10 years and 3737 children aged 10-16 years. Methods: Data were collected on the frequency of consumption of certain foods, physical activity patterns, sedentary habits at home, sleep duration and behaviors such as habits of snacking, skipping breakfast, eating in front of television and frequency of eating out. Simple linear regression analysis of waist circumference on various food items, physical activity, behavior and parental BMI were performed. A path model was developed to R E S E A R C H P A P E R identify potential causal pathways to increase in waist circumference. Results: Increased consumption of bakery items, non vegetarian foods, increased television viewing, decreased sleep duration, eating while watching television, snacking between meals, family meals, skipping breakfast (in older children), and parental BMI were found to be related to waist circumference. Older children possibly underreported their intake of “unhealthy” foods, but not behaviors. Conclusions: This study identified potential behaviors related to waist circumference in urban school children in India. Longitudinal studies with better measures of morbidity and adiposity are warranted in order to derive casual relationships between various determinants and waist circumference.
RESUMEN
Objectives: To develop age and gender specific waist circumference references for urban Indian children aged 3 -16 years. Design: Cross-sectional study. Setting: Urban preschools and schools of Bangalore. Participants: 9060 children (5172 boys and 3888 girls) in the age group of 3-16 years. Methods: Weight, height, and waist circumference were measured using standard anthropometric methodology. Percentiles for waist circumference and Waist/height ratio (W/Ht) for each age and gender were constructed and smoothed using the LMS method. Results: Mean waist circumference increased with age for both girls and boys. The upper end of curve in boys continued to increase, whereas in the girls it tended to plateau at 14 years. The waist circumference of the Indian children from the present study was higher than age and sex matched European children. The proportion of children with W/Ht ratio greater than 0.5 decreased as their age increased. Conclusions: These curves represent the first waist and waist height ratio percentiles for Indian children and could be used as reference values for urban Indian children. We suggest that for a start, the 75th percentile of waist circumference from this study be used as an “action point” for Indian children to identify obesity (as a tautological argument), while retaining the cut-off of 0.5 for the W/Ht ratio; however this underlines the need to derive biologically rational cut-offs that would relate to different levels of risk for adult cardiovascular disease.