SE ASIAN J TROP MED;Southeast Asian J. Trop. Med. Public Health;JAN;2015;46;1
Morbid obesity, the most significant risk factor for development of several respiratory diseases, is linked to decreased pulmonary function. The aim of this study was to determine the relationships between pulmonary function and plasma levels of homeostasis model assessment-insulin resistance (HOMA-IR), insulin, leptin, hs-CRP and fasting glucose. Values were measured in 39 Thai children and adolescents, divided into three groups according to lung function (forced expiratory volume in one second, FEV1); normal (Group A) FEV1 >= 80% (n=19), obese normal (Group B) FEV1, >= 80% (n=14) and obese (Group C) FEV1 <80% (n=6). Body mass index was highest in group C. Groups A and B were comparable for FEV1, forced vital capacity (FVC), maximal voluntary ventilation (MVV) and FEV1/FVC, whereas Group C exhibited significantly reduced FEV1, FVC and MVV but a normal FEV1/FVC ratio. All values except the FEV1/FVC ratio were significantly lower than in groups A and B. Group C had significantly higher levels of leptin, insulin, FG and HOMA-IR than Groups A and B (p<0.001). There was a significant negative correlation between FEV1 and MVV with leptin, insulin and HOMA-IR, but not with high-sensitivity C-reactive protein (hs-CRP). We conclude that FEV1 is reduced in obese children and adolescents and inversely correlates with plasma leptin, insulin and HOMA-IR levels. We have shown that the most important factor in inducing a restrictive lung in these patients may be related to leptin status.