Differences in utilization of asthma drugs between two neighbouring Swedish provinces: relation to treatment in individuals with airway disease

Abstract

Objective. To assess the extent to which drugs were used by individuals found to have asthma in a population survey. To assess the relative influence of the proportion of patients treated and doses reported on the sales of drugs. To study if observed differences in sales of asthma drugs between the county of Jämtland (with high sales) and Gävleborg (with lower sales) correlated to a difference in the control of the disease. Design. A cross-sectional population study with a postal questionnaire followed by an interview and examination of symptomatic individuals. Asthma was diagnosed in subjects reporting a typical history of asthma or repeated episodes of dyspnoea and wheezing, or dry cough combined with reversibility in FEV₁. PEF-variability or PC₂₀ ≤ 4 mg ml^-1. Setting. The county of Jämtland, and Gästrikland, a southern part of the county of Gävleborg in central Sweden. Subjects. All 16 year olds, and 13% (randomly selected) of 30–39 and of 60–69 year olds (totalling 12732 individuals). Subjects reporting airway symptoms in the questionnaire (n = 2100) and 450 asymptomatic controls were further investigated. Main outcome measures. Drug use and symptoms reported by individuals found to have asthma or chronic obstructive pulmonary disease (COPD). Results. Inhaled β₂ agonists and inhaled steroids were used more often by individuals with asthma and COPD in Jämtland. However, regular use was more common in Gävleborg. Most of the asthmatics did not use any medication in spite of the fact that symptoms were commonly reported. The drug combinations most often used were inhaled β₂ agonists alone or in combination with inhaled steroids. There were only minor differences in the prevalence of symptoms reported by individuals with asthma treated in different ways. Conclusion. Differences in the way anti-asthma drugs were used contributed to the observed difference in the sales of drugs. However, this difference was mainly caused by differences in the prevalence of asthma. The goals of asthma management plans were fulfilled only in a minority of patients despite the sales of asthma drugs being high.