Across-shift changes of exhaled nitric oxide and spirometric indices among cotton textile workers.

OBJECTIVES: For the purpose of evaluation of exhaled NO as an index of airway inflammation, we assessed changes in fractional exhaled NO (FeNO) across a work shift and its relationship with respiratory complaints. MATERIAL AND METHODS: Chronic and work-aggravated respiratory complaints were assessed using a questionnaire in 89 male textile workers. FeNO and spirometry were performed before and after a work shift and all the changes were registered. RESULTS: A significant increase in FeNO after a work shift was observed. Post-shift FeNO was significantly higher among the subjects with chronic respiratory complaints. There was an obvious decrease in FVC, and FEV1 after a work shift; however, we couldn't find a significant relationship between changes in respiratory parameters and concentration of inhalable dusts. CONCLUSIONS: FeNO increase after a work shift along with pulmonary function decrement and higher post-shift FeNO among subjects with respiratory complaints makes across-shift FeNO a non-invasive test for assessment of airway hyper-responsiveness in textile workers.

The association between exhaled nitric oxide and sleep apnea: the role of BMI.

BACKGROUND: Obstructive sleep apnea syndrome is associated with airway inflammation. Measurement of exhaled nitric oxide is a non-invasive method for evaluation of airway diseases. It seems that obesity is an exacerbating factor for airway inflammation. We aimed to evaluate the changes of exhaled nitric oxide after sleep in patients suffering from OSA regarding BMI. METHOD: In 54 patients referred for polysomnography, exhaled nitric oxide measurements were performed before and after sleep. Subjects were divided into three categories: normal, obese with sleep apnea and non-obese, based on polysomnographic recordings and BMI. RESULTS: 47 subjects had abnormal apnea/hypopnea index (AHI mean = 39.7) and 7 were normal regarding AHI (AHI mean = 3.0). BMI was significantly correlated to AHI, number of desaturations and hypoxia. Among those with apnea, 31 subjects were obese and 16 were non-obese. Exhaled nitric oxide levels in normal and OSA subjects showed no significant change, but a significant increase was found in obese patients with apnea (14.7 pre-sleep mean, 20.0 post-sleep mean). CONCLUSIONS: Obesity is an effective factor in the inflammation of airways in patients with obstructive apnea.