Patterns of beta-blocker intensification in ambulatory heart failure patients and short-term association with hospitalization

Background: In response to the short-term negative inotropic and chronotropic effects of beta-blockers, heart failure (HF) guidelines recommend initiating beta-blockers at low dose with gradual uptitration as tolerated to doses used in clinical trials. However, patterns and safety of beta-blocker intensification in routine practice are poorly described. Methods: We described beta-blocker intensification among Kaiser Colorado enrollees with a primary discharge diagnosis of HF between 2001-2009. We then assessed beta-blocker intensification in the 30 days prior to first hospital readmission for cases compared to the same time period following index hospitalization for non-rehospitalized matched controls. In separate analysis of the subgroup initiated on beta-blocker after index hospital discharge, we compared adjusted rates of 30-day hospitalization following initiation of high versus low dose beta-blocker. Results: Among 3,227 patients, median age was 76 years and 37% had ejection fraction <= 40% (LVSD). During a median follow up of 669 days, 14% were never on beta-blocker, 21% were initiated on beta-blocker, 43% were discharged on beta-blocker but never uptitrated, and 22% had discharge beta-blocker uptitrated; 63% were readmitted and 49% died. beta-blocker intensification occurred in the 30 days preceding readmission for 39 of 1,674 (2.3%) readmitted cases compared to 27 (1.6%) of matched controls (adjusted OR 1.36, 95% CI 0.81-2.27). Among patients initiated on therapy, readmission over the subsequent 30 days occurred in 6 of 155 (3.9%) prescribed high dose and 9 of 513 (1.8%) prescribed low dose beta-blocker (adjusted OR 3.10, 95% CI 1.02-9.40). For the subgroup with LVSD, findings were not significantly different. Conclusion: While beta-blockers were intensified in nearly half of patients following hospital discharge and high starting dose was associated with increased readmission risk, the prevailing finding was that readmission events were rarely preceded by beta- blocker intensification. These data suggest that beta-blocker intensification is not a major precipitant of hospitalization, provided recommended dosing is followed.