Asthma mortality in portugal : impact of treatment with inhaled corticosteroids and leukotriene receptor antagonists.

Objective: To determine whether the use of inhaled corticosteroids or leukotriene receptor antagonists (LTRAs) has had an impact on asthma mortality in Portugal during the period 1991-2001.

Methods: A population-based ecological study was conducted for the period 1991-2001. Yearly asthma death rates were computed for all ages. Data on sales of inhaled corticosteroids and LTRAs were obtained and expressed in defined daily doses (DDDs)/year. The association between the yearly rate of asthma deaths and consumption of these medications was estimated using Poisson regression.

Results: The rate of asthma death decreased steadily from 39.4 per million inhabitants in 1991 to 14.2 in 2001. At the same time, the use of inhaled corticosteroids in the population increased from 5.8 to 22.2 million DDDs per year. The adjusted rate ratio of asthma death was 0.85 (95% CI 0.78, 0.92) for every additional 5 million DDDs of inhaled corticosteroids per year and 0.84 (95% CI 0.70, 1.02) for every additional 5 million DDDs of LTRAs per year.

Conclusion: The increasing use of inhaled corticosteroids and leukotriene receptor antagonists during the 1990s in Portugal appears to have contributed to the reduction in asthma mortality in that country.