10/22/03 Inhaled corticosteroid (ICS) use in asthma and the prevention of myocardial infarctionSummaryAsthma patients may be at increased risk for cardiovascular problems due to 1) hypoxemia during asthma exacerbations and 2) tachycardias due to heavy use of beta agonists. It is generally felt that chronic treatment of asthma with ICS reduces the number of acute asthma flares and need for rescue use of inhaled beta agonists. Therefore, the question has arisen whether regular ICS use is associated with less frequent cardiac adverse events. Suissa et al of the Royal Victoria Hospital in Montreal, Canada investigated a population of subjects aged 5-44 years who were using anti-asthma drugs between 1975-1991, then followed until 1997 (or death). In a rested case-control approach 105 individuals with a recorded myocardial infarction (M.I.) was compared to 933 controls. They found that the use of ICS during the previous year was associated with a reduced risk for M.I. (risk ratio = 0.56) with a sequential decrease in the risk ratio of 12% associated with each canister of ICS used during the previous year. This reduction in risk for M.I. associated with ICS use was particularly great in those with more severe asthma (risk ratio = 0.19). The authors concluded that treatment of asthma with ICS may reduce the risk of M. I., particularly in those with severe asthma. Reference Am J Med 2003; 115:377-81 Editor's Comments interpreting findings in such analyses of large databases. It certainly is conceivable that reduction of asthma disease activity and the frequency of acute asthma flares (not documented in this study) by ICS therapy would reduce the periods when prominent hypoxemia was present. It would be of considerable interest to follow pulse-ox measurements in a group of severe asthmatics treated or not with ICS to see how often hypoxemia may be prevented by the ICS therapy.
|
