The Role of Long-Acting β-Agonists in the Management of Asthma: Analysis, Meta-Analysis, and More Analysis

We teach that medical decisions, including prescription of treatments, should be informed by the available data addressing the problem in question. Practicing in accord with evidence-based medicine precepts assumes that the practitioner can become familiar with which studies and expert guidelines are relevant to a particular patient and which studies best control for important confounding variables. It assumes, in other words, identification of the “best” evidence. While this process may be straightforward for some conditions or treatment alternatives, it is often quite a challenge.

The place of long-acting β-agonists (LABAs) in the management of asthma exemplifies that reality. Although these agents have been widely prescribed for the management of asthma for some years, their use has been controversial for much of that time. Thus, while several studies have supported the efficacy and safety of LABAs for treating asthma (1-4) (as has 1 recent summary of several Cochrane database reviews [5]), other studies (6-8) have reported very worrisome rates of serious asthma morbidity and death with the use of these drugs. Indeed, some of these latter studies prompted the U.S. Food and Drug Administration to issue a warning about the increased risk for adverse outcomes associated with LABAs.

This issue introduces a new participant in this debate. The report by Salpeter and colleagues (9) details a meta-analysis of 19 randomized, controlled clinical trials involving 33 826 asthmatic patients. The purpose of the study was to estimate the rate of and risk for serious adverse effects from LABAs. The investigators found that use of LABAs was associated with increased asthma exacerbations and increased asthma-related deaths. Moreover, statistically significant increases in hospitalizations …