Comparison of inhaled long-acting β-agonist and anticholinergic effectiveness in older patients with chronic obstructive pulmonary disease: a cohort study.

BACKGROUND: Chronic obstructive pulmonary disease (COPD), a largely preventable and manageable respiratory condition, affects an estimated 12% to 20% of adults. Long-acting inhaled β-agonists and anticholinergics have both been shown to improve COPD outcomes and are recommended for moderate to severe disease; however, little is known about their comparative effectiveness. OBJECTIVE: To compare survival in older patients with COPD who initially receive inhaled long-acting β-agonists with that of patients who receive anticholinergics. DESIGN: Population-based, retrospective cohort study. SETTING: Ontario, Canada. PATIENTS: Patients aged 66 years or older (who carry the largest burden of COPD and for whom data were available) who met a validated case definition of COPD on the basis of health administrative data and were newly prescribed an inhaled long-acting β-agonist or a long-acting anticholinergic (but not both) between 2003 and 2007. Patients were followed for up to 5.5 years. MEASUREMENTS: The primary outcome was all-cause mortality. RESULTS: A total of 46 403 patients with COPD (mean age, 77 years; 49% women) were included. Overall mortality was 38.2%. Mortality was higher in patients initially prescribed a long-acting anticholinergic than in those initially prescribed a long-acting inhaled β-agonist (adjusted hazard ratio, 1.14 [95% CI, 1.09 to 1.19]). Rates of hospitalizations and emergency department visits were also higher in those initially prescribed a long-acting anticholinergic. LIMITATION: Patients were classified as having COPD on the basis of health administrative records, which did not contain information about lung function. CONCLUSION: Older adults initially prescribed long-acting inhaled β-agonists for the management of moderate COPD seem to have lower mortality than those initially prescribed long-acting anticholinergics. Further research is needed to confirm these findings in younger patients and in a randomized, controlled trial. PRIMARY FUNDING SOURCE: Government of Ontario, Canada.