(HealthDay News) — Sex hormones and systemic inflammation may be mediating the obese-asthma phenotype, according to a study published in Allergy.

Hayley A. Scott, PhD, from the University of Newcastle in Australia, and colleagues assessed the associations between sex hormones, oral contraceptive pill (OCP) use, systemic inflammation and airway inflammation in 39 obese and 42 nonobese females and 24 obese and 25 nonobese males with asthma.

The researchers found that obese reproductive-age females had higher sputum neutrophils compared with nonobese reproductive-age females (P=.016), but there was no difference in sputum neutrophils in obese and nonobese males (P=.62) or older females (P=.087). 

Testosterone and OCP use were negative predictors of sputum neutrophils, while C-reactive protein and interleukin-6 were positive predictors of sputum neutrophils. In a multivariate model, BMI and age were not significant predictors. Reproductive-age females using OCP had significantly lower sputum neutrophils than those not using OCP.

“This study suggests that sex hormones and systemic inflammation may be mediating the obese-asthma phenotype,” the researchers wrote.


  1. Scott HA, Gibson PG, Garg ML, Upham JW, Wood LG. Sex Hormones and Systemic Inflammation are Modulators of the Obese-Asthma Phenotype. Allergy. 2016. doi:10.1111/all.12891.