Smoking and Obesity Increase Airway Hyperesponsiveness Risk in the Elderly

Objective: of our study was assessing whether smoking and obesity might affect airways hyperresponsiveness (AHR) differently in younger and older subjects and whether this influence might be due to their different impacts on baseline lung function values at different ages. Methods: 3,903 consecutive adult subjects with normal lung function (1,920 males; mean age 35.1±16.2; median FEV1:97.3% of predicted [interquartile range (IQR):89.7-105.2] and FEV1/FVC: 84.6% of predicted [IQR:79.8-89.2]), having performed a methacholine test, were considered. They were subdivided into three groups according to age (18-39, 40-64 and ≥65 years) and into different sub-groups according to body mass index (BMI) and smoking habits, considering two AHR level cut-offs (PD20≤1600 μg and PD20≤800 μg). Results: PD20 was significantly lower (p 65 (OR: 12.786 [IQR: 1.450-112.753]; p 65 years) (OR: 3.120 [IQR: 1.144-8.509]; p 65 years. A small airway age-related reduction may cause the increased smoking/obesity induced AHR risk in older people.