This US study sought to determine whether low health literacy levels independently predict overall and cause-specific mortality in a prospective cohort of 3260 Medicare managed-care enrollees aged ≥65 years. They were interviewed in 1997 about their demographics and health. The participants also underwent a test of health literacy. Main outcome measures included all-cause and cause-specific (cardiovascular, cancer, and other) mortality using data from the National Death Index through 2003. Adequate (n=2094), marginal (n=366), and inadequate (n=800) health literacy scores were associated with crude mortality rates of 18.9%, 28.7%, and 39.4%, respectively. Adjusted hazard ratios for all-cause mortality were 1.52 and 1.13 for participants with inadequate and marginal health literacy, respectively, compared with participants with adequate health literacy. Participants with inadequate health literacy had higher risk-adjusted rates of cardiovascular death but not of death due to cancer. Years of school completed were only weakly associated with the risk of dying. In conclusion, this study revealed that reading fluency is a more powerful variable than education for examining the association between socioeconomic status and health.
