Differences in utilization of asthma drugs between two neighbouring Swedish provinces: relation to symptom reporting

Utilization of anti-asthma drugs is rapidly increasing and varies markedly between counties in Sweden. In 1989, the sales in the county of Gävleborg were less than 60% of those in neighbouring Jämtland. In order to study the possible reasons for--and effects of--this difference, an epidemiological survey was started in 1989, the first part of which is reported here. A questionnaire was sent to all 16 yr olds, and to a random sample of 30-39 and 60-69 yr olds, in the two counties. A total of 12,500 questionnaires were distributed. Overall response rate was 90%. A total of 7.2% in Jämtland and 5.8% in Gävleborg (p < 0.01) reported that they had had asthma at some time. A similar significant difference between the counties was also present in response to questions on attacks of shortness of breath, wheezing and self-reported diagnosis of asthma, as well as on use of anti-asthma drugs. There were no statistically significant differences between the counties in positive answers to questions concerning history and symptoms of chronic bronchitis; approximately 5% in the oldest age group. The findings support earlier results indicating a high asthma prevalence in northern Sweden. Contrary to reports from other countries, the prevalence was higher in the colder and less urbanised of the two provinces. We conclude that the differences in drug sales between the counties reflect a difference in prevalence of asthmatic symptoms.