Beta-blocker choice and exchangeability in patients with heart failure and chronic obstructive pulmonary disease: an Italian register-based cohort study.

Clinical guidelines suggest that for patients with heart failure and concurrent chronic obstructive pulmonary disease (COPD), metoprolol/bisoprolol/nebivolol should be preferred over carvedilol. However, studies suggest a high proportion of carvedilol usage that remains unexplained. Therefore, we aimed to investigate the predictors of carvedilol choice in patients with heart failure and COPD that were naïve to carvedilol or metoprolol/bisoprolol/nebivolol. Caserta Local Health Unit databases (Italy) were used as data sources. Age, sex, chronic/acute comorbidities, and co-medications were included in a logistic regression model to assess predictors of carvedilol choice. Chronic comorbidities include those defined in the Elixhauser comorbidity index and all hospitalizations within two years prior to the first beta-blocker prescription. Comedications include all redeemed prescriptions within one year prior to the beta-blocker prescription. Kernel density estimations were used to assess the overlap in propensity and preference scores distributions for receiving carvedilol and thereby potential beta-blocker exchangeability. Totally, 10091 patients composed the study population; 2011 were exposed to carvedilol. The overlapping of propensity scores distributions was 57%. Accordingly, the exchangeability was not reached. Atrioventricular block (Odds Ratio, OR 8.20; 95% Confidence Interval, 95% CI 1.30-51.80), cerebrovascular thrombosis (OR 7.06; 95% CI 1.14-43.68), chronic kidney disease (OR 4.32; 95% CI 1.16-16.02), and acute heart failure (OR 1.97; 95% CI 1.28-3.03) hospitalizations were statistically significantly associated with carvedilol choice. Analogously, human insulin (OR 3.00; 95% CI 1.24-7.24), fondaparinux (OR 2.47; 95% CI 1.17-5.21) or strontium ranelate (OR 2.03; 95% CI 1.06-3.90) redeemed prescriptions. In conclusion, this study suggests the absence of beta-blockers exchangeability and a preferential choice of carvedilol in patients with heart failure, COPD and concurrent chronic kidney disease, atrioventricular block, cerebrovascular thrombosis, acute heart failure or redeeming human insulin, fondaparinux or strontium ranelate prescriptions. Therefore, it suggests that choice of prescribing carvedilol over metoprolol/bisoprolol/nebivolol is driven by differences in comorbidities and co-treatments.

Comparison of treatment initiation with bisoprolol vs. enalapril in chronic heart failure patients: rationale and design of CIBIS-III.

BACKGROUND: Angiotensin-converting-enzyme (ACE) inhibitors and beta-blockers are standard therapy for chronic heart failure (CHF). beta-blockers are recommended to be initiated after ACE-inhibitors, but this order is not evidence based. The initiation order may be important since many, especially elderly CHF patients cannot tolerate target doses of both. Data suggest that beta-blockers may be more important to CHF patients than ACE-inhibitors, especially in early stages of CHF. AIMS: To compare the effect on combined death or hospitalisation of initial monotherapy with either bisoprolol or enalapril, followed by combination therapy. METHODS: One-thousand CHF patients without ACE-inhibitor, beta-blocker or angiotensin-receptor-blocker therapy will be randomised 1:1 to monotherapy with either enalapril or bisoprolol for 6 months, followed by combined therapy for 6-18 months. The primary objective is to show non-inferiority for bisoprolol-first vs. enalapril-first regarding combined death or hospitalisation. If that is shown, superiority for bisoprolol-first will be tested. CONCLUSIONS: If the trial shows non-inferiority for bisoprolol-first vs. enalapril-first, the first CHF therapy may be chosen based on individual judgement in each patient. If bisoprolol-first is superior to enalapril-first, a beta-blocker should be given prior to an ACE-inhibitor in CHF, and the paradigm of testing CHF compounds against a background of ACE-inhibitor therapy will be challenged.