Changing asthma mortality and sales of inhaled bronchodilators and anti-asthmatic drugs.

Abstract

Background: Increasing rates of death from asthma in the United States have stabilized somewhat since 1988. Case-control studies have suggested possible adverse effects of inhaled beta-adrenergic agonists that may have contributed to mortality.

Objective: To examine possible relationships between changing asthma mortality and sales of inhaled antiasthmatic drugs.

Methods: The National Center for Health Statistics supplied numbers and rates of death from asthma (ICD 493) by year. The Bureau of the Census supplied population data. IMS America provided estimates of total hospital and drugstore sales of inhaled beta-adrenergic agonists, cromolyn sodium, and inhaled corticosteroids by year and annual sales of AeroChambers and InspirEase kits. I calculated sales of the antiasthmatic drugs as puffs per person in the general population or doses per person for cromolyn sodium, defining a dose as a 20-mg capsule or vial or 2 mg by metered dose inhaler.

Results: Rates of death from asthma in the United States increased from 0.8 per 100,000 general population in 1977 and 1978 to 2.0 in 1989, then decreased to 1.9 in 1990 before increasing again to 2.0 in 1991. Rates of death for blacks 5 through 34 years of age increased from 0.9 in 1980 to 1.3 in 1990 and decreased to 1.2 in 1991. Estimated total hospital and drugstore sales of beta-adrenergic metered dose inhalers increased from 10.3 puffs per person in the general population in 1976 to 31.0 in 1991; those for inhaled corticosteroids, from 0.44 puffs per person in 1976 to 5.44 in 1991. Sales of cromolyn increased from 0.047 doses per person in 1978 to 0.91 in 1991. Sales of AeroChambers and InspirEase kits have also increased.

Conclusions: Since 1988 there has been some moderation in increases in rates of death from asthma while progressive increases in sales of inhaled antiasthmatic drugs have continued. These data are consistent with the likelihood that previous increases in rates of death from asthma were partly due to undertreatment.