Effect of environmental pollution on the control of bronchial asthma and fractional exhaled nitric oxide (FeNO)

Objective: Study the impact that might have the environmental contaminants in the clinical control of asthmatic patients in stable condition. PATIENTS AND METHODS: (April-August 2012) We recruited from the pulmonary function laboratory, asthmatic patients who came to perform lung function tests for its control. We included patients without exacerbations or need for therapeutic changes in the past four weeks, and that had in the vicinity of their usual housing a measurement point of pollutants (MPP). We analyzed the age, gender, body mass index, smoking, usual treatment, presence of pollutants at home and sensitization to aeroallergens.We localized the patients geographically by their postal code and selected the nearest MPP. The measured pollutants were: particles larger than 10 microns in diameter, ozone and nitrogen dioxide. RESULTS: 77 cases. Mean age: 33 (19), 46 women (60 %). The mean values of the data analyzed were: FEV1 88% (SD 14), ACT 15.36 (SD 7.47), FeNO 30 ppb (SD 25.7), BMI 26.43 (SD 5.94), 9 patients (12.3%) were active smokers, 63 patients (84%) were receiving treatment with inhaled steroids and 19 patients (25.3%) used anti-leukotrienes. Presence of pollutants were found in 60% of the houses. The correlation study showed significant association between the values of the ACT with the NO2 measured the day of the interview and with the mean values of NO2 of the previous month, and the value of FeNO with the O3 measured the day of the test. There was no association between the rest of the pollutants and the values of ACT, FeNO or lung function. CONCLUSION:The NO2 seems to be the pollutant most related to the control of the asthma patient not exacerbated.