Prevalence of every night snoring and obstructive sleep apnoeas among 30-69-year-old men in Bologna, Italy.

An epidemiological survey of the prevalence of snoring and sleep apnoeas was performed on 3479 30-69-year-old men living in Bologna, north-east Italy. First a postal questionnaire was sent. It was returned with appropriate answers by 1170. A 20% random sample of those who did not answer were invited by telephone to return the questionnaire. Among these groups 119 (10%) and 19 (5.6%) respectively answered that they always snored. A random sample of 40 every-night snorers were studied by polysomnography. Based on the frequency of every-night snoring and the results of polysomnography we estimated that the minimal prevalence of sleep apnoea among 30-69-year-old men was 2.7% considering an apnoea + hypopnoea index of 10 or more pathological. According to the Lugaresi classification we had a 2.5% prevalence of heavy snorers' disease (HSD) Stage 1 or higher. These figures indicate that obstructive sleep apnoea during sleep is a major public health problem.