Gender Differences in Relationship between Body Mass Index and Asthma.

Background: Asthma is one of the most common chronic diseases in the world. Obesity is the most common comorbidity of asthma and is connected to incidence and course of the disease. Obesity is associated with non-allergic asthma phenotype, but this relation could be influenced by gender. The aim of our study was to determine the relationship between BMI and asthma and to explore possible gender differences.

Subjects And Methods: Study included 149 patients with asthma (examined group) and 153 healthy blood donors (control group). Data from the medical records of patients with asthma were used, and all included subjects had their BMI calculated using standard formula. Data were analyzed using descriptive statistics methods. Data with non-parametric distribution were analysed with Mann-Whitney U test and showed through medians with corresponding interquartile ranges. Statistical significance of BMI differences between non-allergic asthma, allergic asthma and control groups were analyzed by one-way analysis of variance - ANOVA. The results were interpreted at a significance level of P<0.05.

Results: The comparison between median BMI values of two groups shows that examined group of patients with astma has significantly higher median BMI value in comparison with control group (P=0.035). Correlation was stronger for women than men (P=0.002 vs P=0.898). Incresed BMI of the examined group of patients with asthma was not asociated with non-allergic asthma (P=0.085). However, when stratified according to gender, there was a strong association of increased BMI with non-allergic asthma in women (P<0.001).

Conclusion: Patients with asthma in our study have higher BMI in comparison to healthy individuals, which contributes to hypothesis that BMI is a risk factor for development of asthma. We found that possible effect that BMI has on asthma is stronger in women, since there was a strong association between increased BMI and non-allergic asthma only in women.