Obesity–atopy link differs by gender among children

ATLANTA — The association between atopic disease and obesity among children and adolescents was significantly influenced by gender, according to research presented at the annual meeting of the American Academy of Allergy, Asthma & Immunology.

“Our team was interested in looking at the association between obesity and atopy, and specifically how these associations were modified by gender,” Sairaman Nagarajan, MD, MPH, from the SUNY Downstate Medical Center, said during a press conference. “In particular, we wanted to examine individual markers of atopy, such as a history of allergic rhinitis, asthma, atopic dermatitis, and food allergies, as well as variables such as IgE, eosinophils counts, and absolute eosinophil percentages. We wanted to look at the association between each of these variables and the association between obesity as well as the association together with obesity.”

Sairaman Nagarajan

To ascertain this connection, Nagarajan and colleagues conducted a retrospective cohort study of 113 children (aged 0-21 years) in an urban university hospital, 23% of whom were obese (45% were female and 55% male). Following patient evaluation for individual markers of atopy, an atopic score variable was created to summate the total number of atopic diseases per patient.

Chi-square tests, t-tests and linear regression evaluated the association between obesity and atopic disease variables, while interaction effects were measured by gender.

According to study findings, the researchers found no differences in laboratory biomarkers and individual/cumulative atopic disease prevalence in obese children vs. control groups; however, stratification by gender demonstrated that obese females exhibited a higher mean atopic disease score (4.00 vs. 2.62, P<0.001) compared to controls patients.

In addition, obese males exhibited a lower atopic disease score (3.00 vs. 3.42, P<0.001) compared to control patients.

Regression models further demonstrated that obese females exhibited a significantly higher mean atopic disease score (Beta = +1.37, P=0.005) vs. controls, while obese males were protected (Beta = -0.42, P=0.006).

“Urban obese females were much more likely to be atopic by 1.5 diseases; urban males who were obese, on the other hand, were protected,” Nagarajan said. “After adjusting for age and race, it looks like gender, particularly female gender, is a strong positive risk factor for atopy and urban obese females may be particularly likely to benefit from lifestyle and weight reduction therapies in controlling atopy.” – by Bob Stott

Reference:

Nagarajan S, et al. Abstract L38. Presented at: American Academy of Allergy, Asthma & Immunology Annual Meeting; March 3-6, 2017; Atlanta.

Disclosure: The researchers report no relevant financial disclosures.