β-Blocker Use and Incidence of Chronic Obstructive Pulmonary Disease Exacerbations

Michelle Z Farland PharmD; Cassey J Peters PharmD; Juli D Williams MD; Kenneth M Bielak MD; R Eric Heidel PhD; Shaunta' M Ray PharmD

Disclosures

The Annals of Pharmacotherapy. 2013;47(5):651-656. 

In This Article

Abstract and Introduction

Abstract

Background: β-Adrenergic antagonist (β-blocker) use in patients with chronic obstructive pulmonary disease (COPD) has been avoided as a result of potential risk of pulmonary adverse effects. However, recent studies indicate that β-blocker use in patients with COPD can decrease outpatient visits and either decrease or have no effect on the number of hospitalizations. Long-term treatment with β-blockers has been shown to increase survival and decrease exacerbations in patients with COPD.

Objective: To assess the impact of β-blocker use on the incidence of exacerbations in patients with COPD.

Methods: In a retrospective cohort study of patients with COPD from 2 academic primary care practice sites who were seen in 2010, patients were identified using International Classification of Diseases, 9th revision, Clinical Modification codes for COPD and reviewing active medication lists for COPD-specific medications (tiotropium). Patients were classified as either a β-blocker user or a nonuser. Primary outcomes were incidence and severity of COPD exacerbations. Secondary outcomes included COPD exacerbations distinguished by β-blocker cardioselectivity and all-cause hospitalizations.

Results: The study enrolled 412 patients. Of those, 166 patients were β-blocker users and 246 were β-blocker nonusers. β-Blocker users were less likely to have a COPD exacerbation (OR 0.61, 95% CI 0.40–0.93) and had fewer mild exacerbations (OR 0.56; 95% CI 0.34–0.89). There was no significant difference in COPD exacerbations based on β-blocker cardioselectivity (OR 0.84, 95% CI 0.38–1.83). When controlled for, using a backwards stepwise logistic regression, β-blocker use was a variable in the model that predicted exacerbations but alone was not statistically significant (adjusted OR 0.62, 95% CI 0.39–1.01).

Conclusions: Patients with COPD prescribed a β-blocker were significantly less likely to have a COPD exacerbation and had fewer mild COPD exacerbations.

Introduction

Chronic obstructive pulmonary disease (COPD) is the cause of substantial economic and social burden worldwide and is projected to become the third leading cause of death by 2020.[1] Currently, β-adrenergic antagonists (β-blockers) are underused in patients with COPD for the perceived risk of bronchoconstriction.[2–4] In a study by Dransfield et al., only 31% of patients with COPD and an indication for a β-blocker (eg, myocardial infarction or congestive heart failure) received a β-blocker.[5] Multiple studies have shown that use of β-blockers (especially cardioselective β-blockers) is safe in patients with COPD and decreases mortality in patients with coronary vascular disease.[5–11] Conversely, pulmonary hypertension and cor pulmonale may make β-blocker use in patients with COPD less desirable. Because of the infeasibility of right heart catheterization for diagnosis, the prevalence of pulmonary hypertension and cor pulmonale in COPD is unknown, but it occurs more commonly in advanced stages of COPD.[12,13]

Despite an increase in emergency department visits by patients with COPD who are prescribed β-blockers,[9] use of these drugs in patients with COPD has been shown to decrease the number of clinic visits[10] and either decrease or have no effect on the number of hospitalizations when compared to β-blocker nonuse.[9,10] In addition, long-term treatment with β-blockers increased survival and decreased exacerbations in patients with COPD with and without cardiovascular disease.[6–8] Moreover, data suggest that β-blocker use does not significantly reduce lung function in patients with COPD and can be used safely in patients with COPD and coexistent ischemic heart disease, heart failure, or hypertension during hospitalization for a COPD exacerbation.[6,14,15] Although not completely elucidated, animal models have shown β-blocker upregulation of β2-receptors in the lung, possibly enhancing the effects of inhaled β-agonists.[16] This process is theorized to occur in humans as well and could serve as a theory to explain the decrease in COPD exacerbation in patients who use β-blockers.[6]

The objective of this study was to assess the impact of β-blocker use on the incidence and severity of COPD exacerbations in patients with and without cardiovascular disease.

processing....