ARE SYMPTOMS OF OBSTRUCTIVE SLEEP-APNEA SYNDROME-RELATED TO BRONCHITIC SYMPTOMS OR LUNG-FUNCTION IMPAIRMENT - REPORT FROM THE OBSTRUCTIVE LUNG-DISEASE IN NORTHERN SWEDEN STUDY

To investigate whether the high prevalence of symptoms related to obst ructive sleep apnoea syndrome (OSAS) in a bronchitic cohort is correla ted with the bronchitic symptoms or lung function impairment we examin ed two cohorts with bronchitic symptoms (n = 357 and 82) and a referen ce group who had reported no respiratory symptoms in a previous survey in 1986 (n = 140). The study was a part of the Obstructive Lung Disea se in Northern Sweden Study and included clinical examination and lung function tests. Although lung function measured as FEV, percentage pr edicted was correlated with bronchitic symptoms we found that bronchit ic symptoms and body mass index but not lung function impairment were correlated with symptoms related to obstructive sleep apnoea. Accordin g to our findings it was the various bronchitic symptoms such as longs tanding cough, wheezing, sputum production and chronic productive coug h that were correlated with OSAS symptoms. This might be due to increa sed upper airway swelling or increased upper airway resistance, and lu ng function impairment does not seem to be responsible for the high pr evalence of symptoms related to obstructive sleep apnoea in this bronc hitic cohort.