Hospitalization of adults for asthma and inhaled corticosteroid use in an island population

Abstract

Inhaled corticosteroids have been shown to reduce morbidity and the need for hospitalization from asthma. Despite improvements in the therapy of asthma, epidemiologic data from several countries has shown that the hospital admission rates for asthma among adults at a population level are on the increase. The prevalence rate of hospital admission for asthma among Maltese adults aged 15–59 years was determined retrospectively from 1989 to 1993. Concurrent yearly total dispensal of inhaled corticosteroids for the whole population was also calculated. This study was undertaken amongst a well-defined island population served by a single medical facility offering emergency services, and a possible association between these two trends was investigated by means of logistic regression. The age-specific hospital admission rates for asthma decreased from 96.2 (95% CI: 109·7, 82·7) per 100 000 in 1989 to 38·1 (95% CI: 46·4, 29·8) per 100 000 in 1993. The prevalence rates of admission from asthma decreased from 67·6 (95% CI: 78·9, 56·3) per 100 000 in 1989 to 30·6 (95% CI: 38·0, 23·2) per 100 000 in 1993. The dispensal of inhaled beclomethasone dipropionate (BDP) increased from 0·99 defined daily dose (DDD) per 1000 population in 1989 to 3·28 DDD per 1000 in 1993. Logistic regression showed that increasing dispensal of inhaled BDP by 1 DDD per 1000 decreased the odds of an admission from asthma to 0·71 (95% CI: 0·65, 0·78) times their previous value. Similarly, the odds of an individual being hospitalized because of asthma decreased to 0·75 (95% CI: 0·67, 0·83) times their previous value. This study concludes that there was a progressive decrease in hospital admission rates for asthma in adults, and this trend correlates well with increasing use of inhaled corticosteroids at a community level. This must, however, be interpreted with care in light of the fact that increase in utilization of anti-inflammatory therapy probably also reflected improved general and widespread care for asthma.