Leptin and asthma in overweight children at 12 years of age

Pediatr Allergy Immunol. 2004 Dec;15(6):523-30. doi: 10.1111/j.1399-3038.2004.00195.x.


Obesity is suggested as a risk factor for asthma, but the mechanisms are unclear. The relationship between obesity and asthma has not been considered in children born with very low-birth weight (VLBW). We hypothesized that overweight was a contributing factor for asthma in VLBW children, and that leptin and leptin-associated cytokines might play roles in overweight-related asthma. Seventy-four VLBW and 64 normal birth weight (NBW) children participated in a 12-yr follow up study assessing asthma and allergy. Twenty-seven (12 VLBW) of the 138 children were overweight according to the proposed international definition. The diagnosis of current asthma was made by a pediatrician. Serum levels of leptin and interferon (IFN)-gamma were analyzed by enzyme-linked immunosorbent assay (ELISA). Leptin levels were considerably higher in the overweight than in the non-overweight children (median value: 18.1 vs. 2.8 ng/ml, p < 0.001). In the overweight children, current asthmatics had twice as high levels of leptin as children without current asthma (median value: 30.8 vs. 14.3 ng/ml, p = 0.14), but this was not the case in the non-overweight children. IFN-gamma was more often detected in the overweight than in the non-overweight children (61% vs. 12%, p < 0.001), and there was a positive correlation between the levels of leptin and the levels of IFN-gamma (Rho = 0.40, p < 0.001). In the VLBW group, the overweight children had a significantly increased risk for current asthma compared with the non-overweight children after adjustment for the neonatal risk factors [adjusted odds ratio (OR) 5.8, 95% confidence interval (CI): 1.2-27]. Thus, overweight was associated with asthma in the VLBW children. Our hypothesis remained that leptin might be involved in the pathogenesis of asthma in the overweight children, and IFN-gamma might be a pathway in the process of leptin-induced inflammation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Asthma / blood*
  • Asthma / epidemiology*
  • Child
  • Comorbidity
  • Cytokines / blood
  • Enzyme-Linked Immunosorbent Assay / methods
  • Female
  • Follow-Up Studies
  • Humans
  • Infant, Newborn
  • Infant, Very Low Birth Weight / blood*
  • Leptin / blood*
  • Male
  • Obesity / blood*
  • Obesity / epidemiology*
  • Odds Ratio
  • Sex Factors
  • Skin Tests / methods
  • Spirometry / methods
  • Statistics, Nonparametric
  • Sweden / epidemiology


  • Cytokines
  • Leptin