Prevalence of asthma and asthma-like symptoms in an adult population sample from Verona. ECRHS Verona. European Community Respiratory Health Survey.

The aim of the study was to assess the prevalence of asthma and asthma-like symptoms in the general population of Verona. A screening questionnaire, with seven questions on respiratory symptoms, was sent by mail to 3000 randomly selected subjects, aged 20-44 yrs. After three subsequent mailings, nonresponders were interviewed by telephone. The overall response rate was 92%. At least one respiratory symptom was reported by 44% subjects. The prevalence of the most frequent symptoms differed according to the type of contact: early respondents (i.e. those who responded by mail) were more likely to report symptoms than late respondents (i.e. those who were interviewed by telephone). Wheezing was reported by 11.3% of males and 8.0% of females (p < 0.01). The allergic rhinitis and hay-fever prevalence was 16.9% with no differences owing to sex or age. The prevalence of an "episode of asthma" (defined as a self-reported attack of asthma or treatment for asthma) and of "current asthma" (defined as a self-reported attack of asthma, treatment for asthma or wheezing other than due to a cold with dyspnoea in the last 12 months) was 4.1 and 4.7%, respectively. No differences were found on the basis of age and sex. The prevalence of asthma was greater in urban (5.0%) than in suburban (2.7%) areas (p < 0.05), where lower pollution levels were registered. The greater prevalence in urban areas suggests that some factors related to the urban environment could play a role in the development of asthma and asthma-like disorders.