Abstract
BACKGROUND
Approximately half of the US population has marginal or inadequate health literacy, a measure highly associated with health outcomes. This measure is often linked to age and education, but recent evidence from patients with chronic heart failure suggests that much of age-related variability in health literacy can be explained by cognitive abilities (e.g., working memory, processing speed).
OBJECTIVE
We examined the role of cognitive and sensory abilities as mediators of age and education in determining functional health literacy among patients with hypertension.
PARTICIPANTS
Four hundred ninety two community-dwelling adults diagnosed with hypertension (aged 21 to 92 years) participated. They were primarily female (73%), African-American (68%), and reported taking on average 7.8 prescribed medications.
MEASUREMENTS
Before participation in a medication adherence intervention study, participants completed a battery of health literacy-related tasks. They completed tests that measured health literacy [Short Test of Functional Health Literacy in Adults (STOFHLA)], cognitive abilities (working memory, processing speed), sensory abilities (visual acuity and hearing), and physical health.
RESULTS
Regression analyses showed that health literacy was related to age, education, and race (accounting for 24.4% of variance in STOFHLA scores). Cognitive ability accounted for an additional 24% of variance and greatly reduced the influence of age, education, and race (by 75%, 40%, and 48%, respectively).
CONCLUSIONS
When controlling for cognitive and sensory variables, the association of age and education with STOFHLA scores was dramatically reduced. Thus, future interventions aimed at improving self-care for patients with low health literacy should aim to reduce demands on patients’ cognitive abilities.
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ACKNOWLEDGMENTS
Research support from National Institutes of Health (NIH) grants R01 HL69399 and 5K23AG020088-02. Any opinions, findings, and conclusions or recommendations expressed in this publication are those of the authors and do not necessarily reflect the views of the NIH.
Conflict of Interest
None disclosed.
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Levinthal, B.R., Morrow, D.G., Tu, W. et al. Cognition and Health Literacy in Patients with Hypertension. J GEN INTERN MED 23, 1172–1176 (2008). https://doi.org/10.1007/s11606-008-0612-2
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DOI: https://doi.org/10.1007/s11606-008-0612-2