ASTHMA MEDICATIONS AND DISEASE EXACERBATIONS - AN EPIDEMIOLOGIC-STUDYAS A METHOD FOR ASTHMA SURVEILLANCE

Recent experimental and epidemiological studies have suggested that ou tcomes of asthma are significantly influenced by treatment patterns, T his study was conducted in order to investigate the Links between trea tment patterns in asthmatics and occurrence of disease exacerbations. We performed a nested case-control study in a cohort of 680 asthmatics identified between 1986 and 1991 in a drug dispensing database, After validation in a pilot study, the intermittent use of oral corticoster oids was used as a proxy for asthma exacerbations Cases with an exacer bation (n=133) were pair-wise matched with controls. The type of medic ations. used for the usual treatment of asthma were examined in relati on to the risk of asthma exacerbation. The use of oral xanthines and i nhaled fenoterol but not of inhaled salbutamol, corticosteroids, cromo glycate and ipratropium bromide was associated with an increased proba bility of asthma exacerbation. Within the cohort, the proportion of su bjects dispensed inhaled corticosteroids rose from 12 to 27% between 1 986 and 1991, The proportion of subjects using inhaled bronchodilators without inhaled corticosteroids also decreased over this period of ti me. The identification of markers of asthma exacerbations made it poss ible to link the probability of adverse outcome risk for such exacerba tions with treatment patterns, This method could be useful in further development of asthma surveillance using drug dispensing databases.