NEW YORK (Reuters Health) – Older people with chronic obstructive pulmonary disease may live longer if started on an inhaled long-acting beta-agonist than an inhaled long-acting anticholinergic, Canadian investigators report.

During a retrospective cohort study of patients over a 5.5 year period, 39.9% of those given anticholinergics and 36.5% given beta-agonists died, for a “modest but significantly higher adjusted rate of death” in the anticholinergic group (adjusted hazard ratio 1.14, p < 0.001). Results were similar for COPD hospitalizations (aHr 1.13, p < 0.001). Recent studies comparing the inhaled anticholinergic Tiotropium (Spirava) with inhaled beta agonists such as salmeterol (Serevent) or indacatrol (Onbrez), showed conflicting results over a year’s course of treatment in terms of exacerbations. However, no survival benefit of one over the other has been observed. In the Annals of Internal Medicine for May 3, Dr. Andrea Gershon, from the Institute for Clinical Evaluative Sciences in Toronto, Ontario, and her colleagues compared outcomes for the two types of agents using Canadian health administrative databases documenting health services, prescriptions, and mortality, but not lung function. They identified more than 28,000 COPD patients ages 66 and older first prescribed a long-acting anticholinergic and more than 17,000 initially prescribed a long-acting beta-agonist between 2003 and 2007. According to Dr. Gershon’s group, “The incremental risk associated with long-acting anticholinergics seemed to be independent of patient sex or coexisting medical conditions or whether the diagnosis of COPD was confirmed with spirometry.” They acknowledge that they cannot account for potential confounding by indication or by disease severity. “Thus, our findings suggest that long-acting beta-agonists may be more effective than long-acting anticholinergics at improving survival in older patients with COPD,” the authors conclude. They call for randomized control trials to confirm their findings, and a comparison of their risk-benefit ratios. Ann Int Med