Asthma mortality, inhaled steroids, and changing asthma therapy in Argentina (1990-1999)

The asthma managing strategy has evolved and inhaled corticosteroids (ICS) are now the cornerstone of asthma treatment. Their effect on symptoms and exacerbations are well ascertained, whereas their effects on asthma mortality are still matter of debate. This ecological study evaluated asthma mortality rates and drug sales in the decade 1990-1999 in Argentina.

Mortality (overall and adjusted for 5-34 years) was obtained from the Argentinean Epidemiological Institute, and data on the sales of antiasthma drugs were provided by the International Marketing Survey.

There was a significant change in drug sales in the spanned period: ICS +479%, inhaled beta2 agonists +32%, theophylline -63%. The crude and adjusted mortality rates were 3.38 and 0.72 in the 1980-1989 decade, and 2.58 (P<0.05) and 0.38 (P<0.01) in the subsequent one. There was inverse correlation between inhaled corticosteroid sale and age-adjusted (5-34) asthma mortality (r=-0.84; P=0.003), and the same with global mortality rates (r=-0.81; P=0.005). A positive correlation was also seen between theophylline sales and mortality.

The increased sale of ICS and possibly the decrease of theophylline use seem to be the more relevant factors associated with decreased asthma mortality in Argentina.