Health Literacy and Outcomes Among Patients With Heart Failure: A Systematic Review and Meta-Analysis

Objectives: The purpose of this study was to determine if health literacy is associated with mortality, hospitalizations, or emergency department (ED) visits among patients living with heart failure (HF). Background: Growing evidence suggests an association between health literacy and health-related outcomes in patients with HF. Methods: We searched Embase, MEDLINE, PsycINFO, and EBSCO CINAHL from inception through January 1, 2019, with the help of a medical librarian. Eligible studies evaluated health literacy among patients with HF and assessed mortality, hospitalizations, and ED visits for all causes with no exclusion by time, geography, or language. Two reviewers independently selected studies, extracted data, and assessed the methodological quality of the identified studies. Results: We included 15 studies, 11 with an overall high methodological quality. Among the observational studies, an average of 24% of patients had inadequate or marginal health literacy. Inadequate health literacy was associated with higher unadjusted risk for mortality (risk ratio [RR]: 1.67; 95% confidence interval [CI]: 1.18 to 2.36), hospitalizations (RR: 1.19; 95% CI: 1.09 to 1.29), and ED visits (RR: 1.17; 95% CI: 1.03 to 1.32). When the adjusted measurements were combined, inadequate health literacy remained statistically associated with mortality (RR: 1.41; 95% CI: 1.06 to 1.88) and hospitalizations (RR: 1.12; 95% CI: 1.01 to 1.25). Among the 4 interventional studies, 2 effectively improved outcomes among patients with inadequate health literacy. Conclusions: In this study, the estimated prevalence of inadequate health literacy was high, and inadequate health literacy was associated with increased risk of death and hospitalizations. These findings have important clinical and public health implications and warrant measurement of health literacy and deployment of interventions to improve outcomes.