Health Literacy as a Predictor of Adverse Outcomes after Implantation of Left Ventricular Assist Device

Abstract

Introduction: Poor health literacy is associated with worse outcomes in patients with heart failure; however, the role of health literacy in predicting outcomes in patients implanted with left ventricular assist devices (LVADs) has not yet been studied. We hypothesized that health literacy would independently influence clinical outcomes in patients implanted with continuous-flow LVADs (CF-LVADs). Hypothesis: Poor health literacy is associated with worse outcomes in patients with end-stage heart failure implanted with CF-LVADs. Methods: We performed a prospective, single center, cohort study of adult patients with implanted CFLVADs. We identified 118 patients implanted with a Heart Mate II (n5101) or an HVAD (n517) implanted between 8/2005 and 9/2013. Health literacy was assessed using the Rapid Estimate of Adult Literacy in Medicine (REALM), with adequate health literacy defined as a score $ 61 (REALM IV) and poor literacy defined as a score ! 61 (REALM I-III). The primary outcome was combined all-cause death, stroke, gastrointestinal bleeding (GIB), LVAD-related infection, or hemolysis/pump thrombosis; components of the combined primary outcome were analyzed separately as secondary outcomes. Results: The majority of patients were implanted with Heart Mate II LVADs and had an INTERMACS profile of 2. The poor health literacy group (n538) had significantly more patients with a history of smoking (76% vs. 49%, p 5 0.005), a destination therapy strategy (53% vs. 30%, p 5 0.05), and a history of GIB (58% vs. 26%, p 5 0.003). There were no significant differences between cohorts with respect to age, date of implant, BMI, race, sex, etiology of cardiomyopathy, or history of diabetes. During a follow-up period of 88.8 patient-years there were 89 events: 32 in the poor health literacy group and 57 in the adequate health literacy group (84% vs. 71%, HR 1.56, CI 1.01-2.42, p 5 0.0466), see figure. This was driven primarily by GIB events of which there were 22 in both groups (58% vs. 28%, HR 2.57, CI 1.56-5.81). There were no significant differences in individual secondary outcomes of all-cause death,