Body fat mass distribution and interrupter resistance, fractional exhaled nitric oxide, and asthma at school-age

Background: Obesity and asthma often coexist. We hypothesized that detailed body fat distribution measures might be more strongly associated than body mass index (BMI) with childhood asthma.
Objective: We examined the associations of total body and abdominal fat measures with respiratory resistance (Rint), fractional exhaled nitric oxide (FENO), and risks of wheezing and asthma in school-aged children.
Methods: In a population-based prospective cohort study among 6178 children aged 6 years, we measured BMI, fat mass index, android/gynoid ratio, and preperitoneal and subcutaneous fat mass by physical examinations, dual-energy x-ray absorptiometry, and ultrasound, respectively. We performed Rint and FENO measurements, and assessed physician-diagnosed wheezing and asthma by questionnaires.
Results: A higher BMI was associated with a higher Rint and increased risk of wheezing, but not with FENO or asthma. A high fat mass index was associated with a higher Rint. A high android/ gynoid fat mass ratio was associated with a lower FENO, whereas a high preperitoneal fat mass was associated with a higher FENO. Subcutaneous fat mass was not associated with any respiratory outcome.
Conclusions: Studying detailed body fat distribution measures might provide better insight into the obesity-asthma paradigm.