Early Childhood Overweight and Asthma and Allergic Sensitization at 8 Years of Age

Jessica Ohman Magnusson and colleagues have conducted an impressive longitudinal study on a large (2075 children) birth cohort of children followed for 8 years assessing BMI status during the first 7 years of life and asthma and allergic sensitization at age 8 years (1). They found that high BMI at age 7 years was associated with an increased risk of asthma and sensitization to inhalant allergens. They postulated that an association between overweight and asthma is biologically plausible and most likely multifactorial. They also hypothesized that leptin may be one factor that might play a role in this regard. In fact, leptin is an adipokine that also exerts pro-inflammatory activities. The authors cited a study by Mai and coworkers supporting this theory: serum leptin levels were higher in overweight children and with asthma than in controls (2). However, the authors recognized that their study did not allow to draw any conclusion concerning the biological mechanisms underlying the association among overweight, asthma, and sensitization. Therefore, we would like to propose some our studies investigating these issues. Firstly, we provided the first evidence that BMI is significantly associated with bronchial hyperreactivity (mainly severe) both in subjects with asthma and allergic rhinitis (3). More recently, we demonstrated that BMI was significantly related with lung function both at baseline and after bronchodilation test in a large cohort of allergic children (4). Further, we evidenced that serum leptin levels were moderately related with BMI both in allergic males (r= 0.53) and in females (r= 0.58) and overall were very strongly inversely related with the allergy degree (such as the allergen threshold dose at the nasal allergen challenge) both in males (r= -0.85) and in females (r= -0.95) (5). This study thus underlined the close association between leptin levels and allergy severity. Finally, we very recently reported that serum leptin levels significantly decreased (p<0.001) in a group of 35obese children aging 8 years after a 6 month lifestyle intervention (i.e. concerning nutrition and physical activity) (6). This last study confirmed a close link between leptin levels and obese status. Therefore, all these studies suggest that leptin may be a pathogenic link among obesity, asthma, and allergy.

References 1) Ohman Magnusson J, Kull I, Xiao-Mei M, Wickman M, Bergstrom A- Early childhood overweight and asthma and allergic sensitization at 8 years of age. Pediatrics 2012;129:70-6 2) Mai XM, Bottcher MF, Leijon I. Leptin and asthma in overweight children at 12 years of age. Ped Allergy Immunol 2004;15:523-30 3) Ciprandi G, Pistorio A, Tosca MA, Ferraro MR, Cirillo I. Body mass index, respiratory function and bronchial hyperreractivity in allergic rhinitis and asthma. Resp Med 2009;103:289-95 4) Ciprandi G, Brambilla I, Tosca MA, Arrigo T, Salpietro A, Leonardi S, La Rosa M, Marseglia G. Body mass index is related with bronchial function and reversibility in children with allergic rhinitis and asthma. Int J Immunopathol Pharmacol 2011;24:21-4 5) Ciprandi G, Filaci G, Negrini S, DeAmici M, Fenoglio D. Serum leptin levels in patients with pollen-induced allergic rhinitis. Int Arch Allergy Immunol 2009;148:211-8 6) Arrigo T, Gitto L, Munaf? C, Alibrandi A, Salpietro A, Miraglia del Giudice M, Marseglia GL, La Rosa M, Salpietro C., Ciprandi G. Effect of weight reduction on leptin, total ghrelin and obestatin concentrations in prebubescent children. J Biol Reg 2012 (in press)

Conflict of Interest:

None declared