Effect of β

β-Blockers are first-line agents for reduction in symptoms, hospitalization, and mortality in patients with heart failure having reduced ejection fraction (HFrEF). However, the safety and efficacy of continuous β-blocker therapy (BBT) in patients who actively use cocaine remain controversial, and available literature is limited. We aimed to evaluate the effect of BBT on hospital readmission and mortality in patients having HFrEF with concurrent cocaine use. We conducted a retrospective study of patients with a diagnosis of HFrEF between 2011 and 2014 based on International Classification of Diseases 9-Clinical Modification codes. We included patients aged 18 and older who tested positive for cocaine on a urine toxicology test obtained at the time of index admission. Patients were followed for 1 year. Multivariate logistic regression was used to assess the effect of BBT on the 30-day, all-cause and heart failure–related readmissions. The 30-day readmission rates for BBT versus no BBT groups were 20% versus 41% (odds ratio [OR]: 0.17, 95% confidence interval [CI] = 0.05-0.56, P = .004) for heart failure-related readmissions and 25% versus 46% (OR: 0.19, 95% CI = 0.06-0.64, P = .007) for all-cause readmissions. The BBT reduced 30-day, all-cause and heart failure–related readmission rate but not 1-year mortality in patients having HFrEF with concurrent cocaine use