Gain in lung function after weight reduction in severely obese children.

Abstract

The primary objective of this prospective cohort study was to determine the effect of weight loss on pulmonary function values in extremely obese children. Obese children participated in a 26-week in-hospital or outpatient multidisciplinary treatment programme. Waist circumference was measured and pulmonary function tests were performed at enrolment and after 6 months. The data of 112 children were analysed. The children had a mean age of 14.4 (range 8.5-18.9) years and 62.5% were girls. The mean SD score-body mass index (SDS-BMI) was +3.38 at baseline and +2.91 after the intervention. Lung function improved significantly: functional vital capacity increased by 3.08% (95% CI 1.16% to 5.00%) of the predicted value, forced expiratory volume in 1 s (FEV(1)) by 2.91% (95% CI 1.11% to 4.71%) of the predicted value, total lung capacity by 2.27% (95% CI 1.16% to 5.00%) of the predicted value, and expiratory reserve volume (ERV) by 14.8% (95% CI 8.66% to 20.88%) of the predicted value. The increase in ERV correlated with the reduction in SDS-BMI and with the reduction in waist circumference. FEV(1) did not correlate with the reduction in either SDS-BMI or waist circumference. Weight loss in severely obese children correlated with an improvement in lung function, especially ERV. The improvement in ERV correlated with the decrease in SDS-BMI and waist circumference.