Beta-blocker Use in Moderate and Severe Chronic Obstructive Pulmonary Disease
Introduction: The most appropriate choice of pharmacological treatment of heart rhythm disorders occurring in patients with chronic obstructive pulmonary disease (COPD) and cardiovascular comorbidity is often a topic of debate between pulmonologists and cardiologists in clinical practice, although numerous studies and clinical trials have demonstrated evidence to support the use of selective beta-blockers (BBs) in these patients. Aim: To examine the difference in the number of exacerbations in patients treated with a combination of verapamil and digoxin or BB alone in patients with different COPD stages. Patients and methods: The study included 68 patients (n = 68) diagnosed with COPD who were followed-up during a 12-month period, and the number of exacerbations were analyzed. The patients were divided into two groups according to the stage of COPD: GOLD II (moderate), and GOLD III (severe), and in each group a subdivision was established in relation to the use of either a combination of verapamil and digoxin or the use of BBs alone in pharmacological treatment. The inclusion criteria for patients were defined as following: a) established diagnosis of COPD according to present or deteriorated relevant clinical symptoms and signs, b) the ejection fraction (EF) of a left ventricle (LV) >35%, and c) spirometric cut-points classified as GOLD II (FEV1 / FVC <0.7, FEV1 predicted 50-80%), or GOLD III (FEV1/FVC <0.7, FEV1 predicted 30-50%) stage of the COPD. The exclusion criteria were EF of LV <35% and a lethal outcome during a follow-up period (2 patients were encountered). Exacerbation was defined as functional deterioration of the COPD symptoms verified by spirometric functional testing, frequency of hospitalizations according to GOLD stage assignment or verified clinical symptoms deterioration. Results: Regardless the pharmacological treatment, there is a statistically significant increase in the number of COPD exacerbations, in a 12-month period follow-up, in the GOLD III group (severe) compared to the GOLD II group (moderate). In the group of patients taking verapamil and digoxin, a two-tailed t-test was used to analyze the results between the GOLD II and GOLD III stage groups, p = 0.01, and 2. In the group of patients taking BBs, a two-tailed t-test was also used to analyze the results between the GOLD II and GOLD III stage groups, p = 0.003). Within the COPD GOLD II stage group, there appears to be no statistically significant difference in the number of exacerbations between the patients taking verapamil and digoxin (n = 24) and the patients taking BBs alone (n = 15), although, in patients taking BBs alone, there appears to be a trend towards a decrease in the exacerbations compared to the number of exacerbations in patients taking verapamil and digoxin (p = 0.007). Within the COPD GOLD III stage group, there is no difference in the number of exacerbations between the patients taking verapamil and digoxin (n = 20), and the patients taking BBs alone (n = 9), as analyzed by a two-tailed t-test, p = 0.577. Conclusion: Use of selective BBs in the treatment of cardiovascular comorbidity in patients with COPD represents a far better choice of pharmacological approach in the treatment of patients diagnosed with COPD GOLD II (moderate) stage.