Effect of central adiposity on lung function tests in adolescents

Objectives: The objectives of the study were to study the relation of total body adiposity and abdominal adiposity markers with forced expiratory volume in the first second (FEV1) and forced vital capacity (FVC) in adolescents in Bengaluru. Methods: 125 healthy children from a school and 70 asthmatics from Ramaiah hospital between 10 and 15 years were included in the study. Anthropometry including weight, body mass index (BMI), waist and hip circumference, and abdominal height was done in all study adolescents. The subjects were categorized according to BMI. Pulmonary function tests (PFTs) were done by Knudson methodand FEV1, FVC, and peak expiratory flow (PEF) were measured. The patients were classified by their asthma severity according to GINA guidelines. Results: BMI, weight, waist and hip circumference correlated with abdominal height in male asthmatics and controls where they revealed significant correlations with FEV1/FVC% ratio. In females, abdominal height correlated with BMI, weight, waist and hip circumference in both the groups. PEF correlated with BMI, weight, waist circumference, and abdominal height in healthy females. FEV1/FVC correlated with BMI, abdominal height in female asthmatics, with weight in healthy females.Independent predictors of FEV1/FVC% ratio were hip circumference in males and abdominal height, and waist circumference in females. Conclusion: Increase in obesity is associated with reduced lung volumes and flows. The abdominal adiposity markers (waist and hip circumference, and abdominal height) are significant and effective predictors of obesity and the variations of PFT’s than total adiposity markers (BMI and weight)