Literacy, Cognitive Function, and Health: Results of the LitCog Study

Abstract

BACKGROUND: Emerging evidence suggests the relationship between health literacy and health outcomes could be explained by cognitive abilities. OBJECTIVE:To investigate to what degree cognitive skills explain associations between health literacy, performance on common health tasks, and functional health status. DESIGN: Two face-to-face, structured interviews spaced a week apart with three health literacy assessments and a comprehensive cognitive battery measuring 'fluid' abilities necessary to learn and apply new information, and 'crystallized' abilities such as background knowledge. SETTING: An academic general internal medicine practice and three federally qualified health centers in Chicago, Illinois. PATIENTS: Eight hundred and eighty-two Englishspeaking adults ages 55 to 74. MEASUREMENTS: Health literacy was measured using the Rapid Estimate of Adult Literacy in Medicine (REALM), Test of Functional Health Literacy in Adults (TOFHLA), and Newest Vital Sign (NVS). Performance on common health tasks were globally assessed and categorized as 1) comprehending print information, 2) recalling spoken information, 3) recalling multimedia information, 4) dosing and organizing medication, and 5) healthcare problem-solving. RESULTS: Health literacy measures were strongly correlated with fluid and crystallized cognitive abilities (range: r=0.57 to 0.77, all p<0.001). Lower health literacy and weaker fluid and crystallized abilities were associated with poorer performance on healthcare tasks. In multivariable analyses, the association between health literacy and task performance was substantially reduced once fluid and crystallized cognitive abilities were entered into models (without cognitive abilities: β=−28.9, 95 % Confidence Interval (CI) -31.4

Health Literacy and the Digital Divide Among Older Americans

“…These patterns persisted even after adjusting for demographic covariates including age, sex, and race, as well as clinical covariates such as chronic medical conditions, functional impairment, and cognition. Interestingly, though past evidence has suggested that health literacy may be a proxy for general cognition, 40,41 our results suggest that each has an independent relationship with likelihood of regular Internet use. We found that health literacy was a more important predictor of Internet use for medical or health information than was level of cognitive function, suggesting that interventions specifically targeting health literacy among Internet-using older adults may be effective for narrowing the digital divide by facilitating their ability to obtain medical information online.…”

“…Other covariates were as expected: age greater than 75 years, education less than high school, and low cognitive function were also associated with a lack of regular Internet use. Interestingly, although existing evidence suggests that the relationship between health literacy and other health-related measures in many cases is rendered insignificant by the inclusion of measures of general cognitive function, 40,41 our results remained robust even after adjusting for these. We also repeated the regression analyses entering scores on each of the three cognitive tests separately (rather than in the combined 27-point scale), and our results were unchanged, so we are reporting the results using the combined 27-point scale.…”

The Mini Mental Status Exam as a Surrogate Measure of Health Literacy

“…A more complete description of the LitCog study and its battery has been published previously. 13 Northwestern University's Institutional Review Board approved this study.…”

“…Specifically, more recent studies have found that health literacy assessments are strongly correlated with various tests of cognitive abilities, 11,12 such that the relationship between literacy and health outcomes may in part be explained by a more global cognitive skill set. 13 If cognitive and health literacy measures are revealing a similar latent trait, then a clinical screening tool such as the Mini Mental Status Examination (MMSE), 14,15 a brief global assessment of cognitive function, may viably serve as a surrogate measure to identify patients at risk for limited health literacy. The advantages of using the MMSE in this manner could be twofold: 1) it would offer greater face validity of the actual problem, that being limited proficiency for understanding and acting on health information; and 2) the MMSE is already a well-vetted assessment used for clinical purposes.…”

The role of the nurse in improving health literacy among older adults

“…Older adults can have lower health literacy levels because of long-term influences, such as limited education or limited knowledge of expressing themselves [8], yet such limited levels of health literacy can also be, according to the findings of a number of researches that did not include dementia patients, linked to an age-related cognitive decline [9,10,11]. Besides that, several other resources, such as education, word knowledge, and decision-making manner, contribute to health literacy and are connected to recollection or memory function.…”