Abstract
BACKGROUND: The burden of substance abuse among patients with heart failure and its association with subsequent emergency department visits and hospital admissions are poorly characterized. METHODS: We evaluated the medical records of patients with a diagnosis of heart failure treated at the University of California-San Diego from 2005 to 2016. We identified substance abuse via diagnosis codes or urine drug screens. We used Poisson regression to evaluate the incidence rate ratios (IRR) of substance abuse for emergency department visits or hospitalizations with a primary diagnosis of heart failure, adjusted for age, sex, race, medical insurance status, and medical diagnoses. RESULTS: We identified 11,268 patients with heart failure and 15,909 hospital encounters for heart failure over 49,712 person-years of follow-up. Substance abuse was diagnosed in 15.2% of patients. Disorders such as methamphetamine abuse (prevalence 5.2%, IRR 1.96, 95% confidence interval [CI] 1.85-2.07), opioid use and abuse (8.2%, IRR 1.54, 95% CI 1.47-1.61), and alcohol abuse (4.5%, IRR 1.51, 95% CI 1.42-1.60) were associated with a greater number of hospital encounters for heart failure, with associations that were comparable to diagnoses such as atrial fibrillation (37%, IRR 1.78, 95% CI 1.73-1.84), ischemic heart disease (24%, IRR 1.67, 95% CI 1.62-1.73), and chronic kidney disease (26%, IRR 1.57, 95% CI 1.51-1.62). CONCLUSIONS: Although less prevalent than common medical comorbidities in patients with heart failure, substance-abuse disorders are significant sources of morbidity that are independently associated with emergency department visits and hospitalizations for heart failure. Greater recognition and treatment of substance abuse may improve outcomes among patients with heart failure.