The Serum Level of Leptin in Patients with Obesity: Asthmatic and Non-Asthmatic Children

Leptin is a pro-inflammatory cytokine produced by adipose tissue. Considering the association between obesity and asthma, the current study aimed at investigating if leptin was in the pathway of obesity-asthma relationship in children and if it played a distinctive role in children with asthma and obesity versus the ones with obesity but without asthma.
The current case-control study was conducted on 23 children with asthma and obesity and 13 children with obesity but without asthma (body mass index ≥ 95%) aged 6 to 15 years from October 2011 to October 2012 in Mofid Children’s Hospital, Tehran, Iran. Group 1 included 23 children with asthma and obesity with a mean BMI of 24.3 kg/m2, while group 2, included 13 cases with obesity but without asthma and a mean BMI of 26.6 kg/m2. Both groups were evaluated for their serum leptin, triglyceride, cholesterol, and IgE mean levels. The serum leptin levels were measured by the enzyme-linked immunosorbent assay (ELISA) technique. The results were analyzed with SPSS version 19. The Mann-Whitney test was employed to compare the results.
The mean serum leptin level in the children with asthma and obesity was 2.19 ng/mL and in the ones with obesity but without asthma was 2.85 ng/mL (P = 0.006). The mean serum triglyceride and cholesterol levels in the group 1 were 175.4 mg/dL and 189 mg/dL, respectively, while in the group 2 were 175.4 mg/dL and 226.2 mg/dL, respectively. A significant difference was observed in serum leptin levels between the children in groups 1 and 2 (P = 0.006), but surprisingly the increased leptin was detected in the group 2 subjects.
The current study findings indicated that serum levels of leptin were significantly higher in the cases with obesity but without asthma. Therefore, other cytokines appeared to play a role in the children with asthma and obesity.