Increased body mass index and bronchial impairment in allergic rhinitis

Background: Several studies have outlined a possible relationship between an increased body mass index (BMI) and respiratory allergic diseases, such as asthma and allergic rhinitis (AR). The aim of this study was to analyze the relationship among BMI, spirometry, bronchial hyperreactivity (BHR), and fractional concentration of exhaled nitric oxide (FeNO) in a cohort of AR patients. Methods: The study included 155 patients with persistent AR alone and 155 healthy controls. All subjects were evaluated performing skin-prick test, spirometry, bronchoprovocation test with methacholine, and FeNO measurement. Results: BMI values were significantly higher in AR patients than in control subjects (p = 0.038). Overweight/obese AR patients had more altered functional and inflammatory parameters than normal weight patients. BMI > 25 is a risk factor for (i) early bronchial airflow limitation (odds ratio [OR], 3.81), (ii) high FeNO values (OR, 1.96), and BHR (OR, 3.29). Conclusions: The present study may suggest that BMI assessment should be routinely considered in AR patients for assessing risk for early bronchial impairment, such as suggesting possible evolution to asthma.