Leptin, as a major adipokine, positively correlates with the body’s fat, while atopy is an important feature in the development of childhood asthma. We aimed to evaluate the relationship between leptin, parameters of obesity, and atopy in children with asthma. The study included 112 children (73 boys, 39 girls, mean age 11.1±2.4). 41 were overweight, 38 had asthma and a normal body mass index (BMI), and 33 were overweight asthmatics. Serum leptin levels, BMI, waist circumference (WC), and waist to hips ratio (WHR) were measured. Skin prick test (SPT)/CAP, total serum IgE, fractional exhaled nitric oxide (FeNO), and pulmonary function tests were performed. In asthmatic children, serum leptin median level was 9.2±16.2 ng/ml, in overweight children was 30.6±21.6 ng/ml, and in overweight asthmatics was 31.1±20.3 ng/ml with a significant difference between the groups (p=0.0374), yet with a significantly lower median level in the group of children with asthma compared to the overweight children: with asthma (p=0.00001) and without asthma (p=0.00001). In the three groups of patients, BMI and WC displayed a significant positive correlation with leptin (for BMI r=0.652 vs. r=0.530 vs. r=0.563, respectively and for WC r=0.508 vs. r=0.426 vs. r=0.527, respectively). No significant correlations of leptin within atopy parameters (Eo, IgE, SPT/CAP, FeNO) in all three analyzed groups (p>0.05) was detected.
Conclusion: Atopy was not confirmed as an underlying mechanism of the association between asthma and being overweight. Leptin had a significant linear correlation as a parameter of central obesity with BMI and WC in all three groups, but not with WHR.