Relative influence of overall and central body adiposity on lung function and development of lung function predictive model for adolescents in Tripura

Abstract

Background: Population-specific reference values are necessary for maintaining the reliability of pulmonary function evaluation. There are very few studies that have included body adiposity markers as the predictors of lung function, instead of age and height. Objectives: A gender-specific lung function predictive model of adolescents was developed using overall and central adiposity markers. The relative influences of both markers on pulmonary functions were also evaluated. Methods: Anthropometric and pulmonary function parameters of the subjects were recorded. The percentage body fat, fat mass (FM), fat-free mass (FFM), and body density were calculated. Statistical analysis was done using SPSS 16.0. Results: Significant differences between sexes for anthropometric measures were observed. The mean values of waist circumference (71.94 ± 2.33 mm for female vs. 71.37 ± 2.25 mm for male; P < 0.0005), body composition (5.83 ± 1.27 mm for female vs. 4.71 ± 0.83 mm for male; P < 0.0005), and sum of skinfolds (35.71 ± 4.48 mm for female vs. 34.66 ± 3.01 mm for male; P < 0.0005) were higher in female in comparison to male. Males had significantly higher subscapular skinfold thickness (9.39 ± 1.05 mm, compared with 9.17 ± 1.05 mm for females; P = 0.003). Mean values of central adiposity markers such as waist-hip-ratio (0.88 ± 0.01 for female vs. 0.87 ± 0.01, for male; P < 0.0005) and waist-to-height ratio (0.47 ± 0.004 for female vs. 0.47 ± 0.01, for male; P = 0.002) as well as overall adiposity markers such as percentage body fat (23.81 ± 1.11 for female vs. 18.98 ± 1.20, for male; P = 0.001) and FM (11.27 ± 1.83 kg for female vs. 8.94 ± 1.16, kg for male; P < 0.0005) were significantly higher in female compared to male. Mean FFM (38.17 ± 4.38 mm for male vs. 35.81 ± 3.93 mm for female; P < 0.0005) was significantly higher in male. All the pulmonary function parameters were significantly higher in male compared to female. Results showed the existence of significant mean differences in pulmonary function measures across the three body fat percentage groups in both sexes, with linear decrease of mean values of lung function with the increase of body fat percentage. Post hoc pair-wise multiple comparisons were done to compare the lung function between groups. Conclusion: Overall adiposity marker would explain variation in the pulmonary function parameters better than central adiposity markers in adolescents of both sexes.