Exhaled nitric oxide in overweight and obese asthma patients compared to normal weight asthmatic patients

Abstract

Introduction: The differences in phenotypes of the asthma are increasingly recognized with potential implications in treatments of these phenotypes. We investigated the difference in exhaled nitric oxide (eNO) level in patients with obese and non-obese asthmatics. Materials and Methods: 135 patients with asthma without prior history of treatment with inhaled or systemic steroids were selected from a respiratory subspecialty clinic in Tabriz, Iran. After full history and physical examination all patients had eNO measurement (using NObreath provided by Bedfont, UK) and spirometry (using Jaeger spirometer, Germany) performed with standard techniques. The level of eNO compared in asthma patients from different BMI groups and also the correlation of the eNO with different parameters of pulmonary function was analyzed. Results: The eNo levels in overweight and obese asthmatics with BMI of 25 kg/m2 or higher were significantly lower than asthma patients with BMI less than 25 kg/m2( 44.1 ppb versus 63.9 ppb respectively; p Conclusion and Clinical Implications: These findings indicates that eNO is lower in overweight and obese asthmatic patients with associated metabolic and mitochondrial changes compared with normal weight asthmatics and this is in line with possible differences in disease mechanisms with potential clinical implications of varied efficacy of drugs in these phenotypes of asthma.