Reading ability mediates the relationship between education and executive function tasks

Cognitive enrichment and education quality moderate cognitive dysfunction in black and white adults with multiple sclerosis

OBJECTIVE

To examine the extent to which three sociobehavioral proxies of cognitive reserve-years of education, education quality, and cognitive enrichment-differ in their prediction of cognitive performance among Black and White people with MS (PwMS).

METHODS

82 PwMS (Black n = 41, White n = 41) underwent a neurological examination and a neuropsychological evaluation that included tests of word recognition (Wechsler Test of Adult Reading) as well as measures of verbal memory, visuospatial memory, and processing speed (the Brief International Cognitive Assessment for MS; BICAMS). Participants rated their lifetime engagement in various cognitively-enriching activities (Cognitive Reserve Scale).

RESULTS

For the full sample, education quality and cognitive enrichment were more strongly associated with cognitive performance than were years of education. Cognitive enrichment was not associated with cognitive performance among participants with high education quality. In contrast, among participants with low education quality, cognitive enrichment was strongly associated with cognitive performance, suggesting that high engagement in cognitively-enriching activities provided similar protection to high education quality. Furthermore, among Black participants, cognitive enrichment and educational quality moderated the relationship between disability level and cognitive performance. In contrast, among White participants, cognitive enrichment did not provide additional protection beyond the buffering effect of education quality.

CONCLUSIONS

PwMS can successfully build reserve through multiple routes, including formal education or informal cognitive enrichment. Treatment for MS should incorporate cognitively-enriching activities to build resilience against cognitive decline, particularly for members of marginalized racial/ethnic groups, who are at greatest risk for poor health outcomes, and for whom years of education may not best reflect education quality.

Cultural influence on clock drawing test: A systematic review

OBJECTIVE

Dementia among migrants is an emerging phenomenon worldwide and the development of neuropsychological tests sensitive to cultural differences is increasingly regarded as a priority. The Clock Drawing Test (CDT) is one of the most used screening tools for the detection of cognitive decline. Nevertheless, there is still a debate about its adoption as a cross-cultural assessment.

METHODS

To identify cultural variables influencing performance at CDT, we performed a systematic review of literature on three databases of all studies considering the role of at least one of the following: (1) language; (2) education; (3) literacy; (4) acculturation; and (5) ethnicity.

RESULTS

We extrapolated 160 analyses from 105 studies. Overall, an influence of cultural determinants on performance at CDT was found in 127 analyses (79.4%). Regarding specific cultural factors, 22 analyses investigated the effect of ethnicity on CDT scores, reporting conflicting results. Only two scoring systems turned out to be sufficiently accurate in a multicultural population. Language influenced performance in only 1 out of 8 analyses. A higher level of education positively influenced test performance in 118 out of 154 analyses (76.6%), and a better quality of education in 1 analysis out of 2. A negative influence of illiteracy on CDT performance emerged in 9 out of 10 analyses. Acculturation affected performances at CDT in 1 out of 2 studies.

CONCLUSIONS

Based on the present findings, caution is needed when using CDT in a multicultural context, even if it requires limited linguistic competence.

Reading activities compensate for low education-related cognitive deficits

BACKGROUND

The incidence of cognitive impairment is increasing with an aging population. Developing effective strategies is essential to prevent dementia. Higher education level is associated with better baseline cognitive performance, and reading activities can slow down cognitive decline. However, it is unclear whether education and reading activities are synergistic or independent contributors to cognitive performance.

METHODS

This was a sub-study of an ongoing prospective community cohort of China National Clinical Research Center Alzheimer's Disease and Neurodegenerative Disorder Research (CANDOR). Demographic and clinical information, educational levels, and reading activities were collected. All participants finished neuropsychological testing batteries and brain MRIs. We analyzed cognitive performance and brain structures with education and reading activities.

RESULTS

Four hundred fifty-nine subjectively cognitively normal participants were enrolled in the study. One hundred sixty-nine (36.82%) of them had regular reading activities. Participants in the reading group had better performance in all cognitive tests compared with those in the non-reading group, but no difference in brain MRI variables. Participants with higher education levels (more than 13 years) had better cognitive performance and higher hippocampal volumes. In low education groups (less than 12 years), more reading activities were associated with better cognitive test scores.

CONCLUSIONS

Both education and reading activities are important and synergistic for baseline cognitive function. Higher education level is associated with larger hippocampal volumes. Education may stimulate the growth and development of the hippocampus. Reading activities help to maintain and improve cognitive function in people with low levels of education.

TRIAL REGISTRATION

NCT04320368.

Markers of a plant-based diet relate to memory and executive function in older adults

BACKGROUND

Although it is known that plant-based foods are important for physical health, little is known about the relationship between plant-based foods and cognitive health. Emerging evidence suggests that some macronutrients may influence cognition, but it is unclear which domains of cognition are involved; more importantly, it is unknown how a plant-based diet relates to cognition.

OBJECTIVE

To examine associations between a plant-based dietary pattern and cognitive functioning.

METHODS

Participants were 3,039 older adults who participated in the 2011-2014 waves of the National Health and Nutrition Examination Survey (NHANES). The present cross-sectional study used data on macronutrient intake from 24-hour dietary interviews, as well as performance on tests of long-term memory and executive function (i.e., delayed word recall, digit symbol substitution test, and animal fluency). Principal component analysis was used to extract a dietary pattern consistent with a plant-based diet.

RESULTS

Greater adherence to a dietary pattern consistent with a plant-based diet was related to better performance on all cognitive tasks. Secondary analyses indicated that the associations between a plant-based dietary pattern and executive function accounted for the association between a plant-based dietary pattern and memory. Furthermore, this same plant-based dietary pattern was associated with reduced baseline inflammation in a separate dataset.

CONCLUSIONS

Experimental manipulations are needed to determine the potential causal relations of these associations, but these results suggest that a plant-based diet relates to better cognition, especially through improved executive control. Future work should also attempt to extend these results by examining potential mechanisms underlying these associations, such as reduced inflammation.

Age of First Exposure to Contact and Collision Sports and Later in Life Brain Health: A Narrative Review

A controversial theory proposes that playing tackle football before the age of 12 causes later in life brain health problems. This theory arose from a small study of 42 retired National Football League (NFL) players, which reported that those who started playing tackle football at a younger age performed worse on selected neuropsychological tests and a word reading test. The authors concluded that these differences were likely due to greater exposure to repetitive neurotrauma during a developmentally sensitive maturational period in their lives. Several subsequent studies of current high school and collegiate contact/collision sports athletes, and former high school, collegiate, and professional tackle football players have not replicated these findings. This narrative review aims to (i) discuss the fundamental concepts, issues, and controversies surrounding existing research on age of first exposure (AFE) to contact/collision sport, and (ii) provide a balanced interpretation, including risk of bias assessment findings, of this body of evidence. Among 21 studies, 11 studies examined former athletes, 8 studies examined current athletes, and 2 studies examined both former and current athletes. Although the literature on whether younger AFE to tackle football is associated with later in life cognitive, neurobehavioral, or mental health problems in former NFL players is mixed, the largest study of retired NFL players (N = 3,506) suggested there was not a significant association between earlier AFE to organized tackle football and worse subjectively experienced cognitive functioning, depression, or anxiety. Furthermore, no published studies of current athletes show a significant association between playing tackle football (or other contact/collision sports) before the age of 12 and cognitive, neurobehavioral, or mental health problems. It is important to note that all studies were judged to be at high overall risk of bias, indicating that more methodologically rigorous research is needed to understand whether there is an association between AFE to contact/collision sports and later in life brain health. The accumulated research to date suggests that earlier AFE to contact/collision sports is not associated with worse cognitive functioning or mental health in (i) current high school athletes, (ii) current collegiate athletes, or (iii) middle-aged men who played high school football. The literature on former NFL players is mixed and does not, at present, clearly support the theory that exposure to tackle football before age 12 is associated with later in life cognitive impairment or mental health problems.

Parental Educational Attainment, the Superior Temporal Cortical Surface Area, and Reading Ability among American Children: A Test of Marginalization-Related Diminished Returns

BACKGROUND

Recent studies have shown that parental educational attainment is associated with a larger superior temporal cortical surface area associated with higher reading ability in children. Simultaneously, the marginalization-related diminished returns (MDRs) framework suggests that, due to structural racism and social stratification, returns of parental education are smaller for black and other racial/ethnic minority children compared to their white counterparts.

PURPOSE

This study used a large national sample of 9-10-year-old American children to investigate associations between parental educational attainment, the right and left superior temporal cortical surface area, and reading ability across diverse racial/ethnic groups.

METHODS

This was a cross-sectional analysis that included 10,817 9-10-year-old children from the Adolescent Brain Cognitive Development (ABCD) study. Parental educational attainment was treated as a five-level categorical variable. Children's right and left superior temporal cortical surface area and reading ability were continuous variables. Race/ethnicity was the moderator. To adjust for the nested nature of the ABCD data, mixed-effects regression models were used to test the associations between parental education, superior temporal cortical surface area, and reading ability overall and by race/ethnicity.

RESULTS

Overall, high parental educational attainment was associated with greater superior temporal cortical surface area and reading ability in children. In the pooled sample, we found statistically significant interactions between race/ethnicity and parental educational attainment on children's right and left superior temporal cortical surface area, suggesting that high parental educational attainment has a smaller boosting effect on children's superior temporal cortical surface area for black than white children. We also found a significant interaction between race and the left superior temporal surface area on reading ability, indicating weaker associations for Alaskan Natives, Native Hawaiians, and Pacific Islanders (AIAN/NHPI) than white children. We also found interactions between race and parental educational attainment on reading ability, indicating more potent effects for black children than white children.

CONCLUSION

While parental educational attainment may improve children's superior temporal cortical surface area, promoting reading ability, this effect may be unequal across racial/ethnic groups. To minimize the racial/ethnic gap in children's brain development and school achievement, we need to address societal barriers that diminish parental educational attainment's marginal returns for middle-class minority families. Social and public policies need to go beyond equal access and address structural and societal barriers that hinder middle-class families of color and their children. Future research should test how racism, social stratification, segregation, and discrimination, which shape the daily lives of non-white individuals, take a toll on children's brains and academic development.

Reading activity prevents long-term decline in cognitive function in older people: evidence from a 14-year longitudinal study

OBJECTIVE

This study examined the effect of daily life reading activity on the risk of cognitive decline and whether the effect differs regarding education levels.

DESIGN

A longitudinal study with 6-, 10-, and 14-year follow-up.

SETTING

Face-to-face interviews with structured questionnaires at home.

PARTICIPANTS

A representative sample of 1,962 Taiwanese community-dwelling older persons aged 64 and above, followed up in four waves of surveys over 14 years.

MEASUREMENTS

Baseline reading frequencies were measured based on a scale of leisure activity. The Short Portable Mental Status Questionnaire was used to measure cognitive performance. We performed logistic regression to assess associations between baseline reading and later cognitive decline. Interaction terms between reading and education were to compare the reading effects on cognitive decline at different education levels.

RESULTS

After adjusting for covariates, those with higher reading frequencies (≥1 time a week) were less likely to have cognitive decline at 6-year (adjusted odds ratio [AOR]: 0.54; 95% confidence interval [CI]: 0.34-0.86), 10-year (AOR: 0.58, 95% CI: 0.37-0.92), and 14-year (AOR: 0.54, 95% CI: 0.34-0.86); in a 14-year follow-up, a reduced risk of cognitive decline was observed among older people with higher reading frequencies versus lower ones at all educational levels.

CONCLUSIONS

Reading was protective of cognitive function in later life. Frequent reading activities were associated with a reduced risk of cognitive decline for older adults at all levels of education in the long term.

Dysfunction of the left angular gyrus may be associated with writing errors in ALS

Background: Language dysfunction is a feature of cognitive impairment in amyotrophic lateral sclerosis (ALS) that may compromise communication. Objective: To elucidate language dysfunction in patients with ALS and its relationship with other neuropsychological tests and to identify the brain regions associated with this dysfunction using perfusion image. Methods: Overall, 37 patients with ALS were included in this study. Their neuropsychological function was investigated using the Western Aphasia Battery (WAB), Frontal Assessment Battery and Behavioral Assessment of the Dysexecutive Syndrome. N-isopropyl-p-[¹²³I] iodoamphetamine single-photon emission computed tomography was used to examine regional cerebral blood flow and its relationship with WAB scores was investigated using multiple regression analyses, controlled for age, sex and years of education. Results: Frequency of language abnormality in ALS was 8.5% for spontaneous speech, 25.7% for auditory verbal comprehension, 8.8% for repetition, 14.7% for naming, 17.6% for reading and 51.4% for writing. The writing error was mainly omission and substitution of kana letters. Executive tests were correlated with naming (r > 0.5, p < 0.001) and reading (r > 0.4, p < 0.01) scores. With respect to the writing sub-test, positive perfusional relationship was only detected in the left angular gyrus. Conclusions: The left angular gyrus is the region associated with the writing errors observed in ALS.

The 1-min Screening Test for Reading Problems in College Students: Psychometric Properties of the 1-min TIL

Reading is a central cognitive domain, but little research has been devoted to standardized tests for adults. We, thus, examined the psychometric properties of the 1-min version of Teste de Idade de Leitura (Reading Age Test; 1-min TIL), the Portuguese version of Lobrot L3 test, in three experiments with college students: typical readers in Experiment 1A and B, dyslexic readers and chronological age controls in Experiment 2. In Experiment 1A, test-retest reliability and convergent validity were evaluated in 185 students. Reliability was >.70, and phonological decoding underpinned 1-min TIL. In Experiment 1B, internal consistency was assessed by presenting two 45-s versions of the test to 19 students, and performance in these versions was significantly associated (r = .78). In Experiment 2, construct validity, criterion validity and clinical utility of 1-min TIL were investigated. A multiple regression analysis corroborated construct validity; both phonological decoding and listening comprehension were reliable predictors of 1-min TIL scores. Logistic regression and receiver operating characteristics analyses revealed the high accuracy of this test in distinguishing dyslexic from typical readers. Therefore, the 1-min TIL, which assesses reading comprehension and potential reading difficulties in college students, has the necessary psychometric properties to become a useful screening instrument in neuropsychological assessment and research. Copyright © 2017 John Wiley & Sons, Ltd.

Effects of education and race on cognitive decline: An integrative study of generalizability versus study-specific results

The objective of the study was to examine variability across multiple prospective cohort studies in level and rate of cognitive decline by race/ethnicity and years of education. We compare data across studies, we harmonized estimates of common latent factors representing overall or general cognitive performance, memory, and executive function derived from the: (a) Washington Heights, Hamilton Heights, Inwood Columbia Aging Project (N = 4,115), (b) Spanish and English Neuropsychological Assessment Scales (N = 525), (c) Duke Memory, Health, and Aging study (N = 578), and (d) Neurocognitive Outcomes of Depression in the Elderly (N = 585). We modeled cognitive change over age for cognitive outcomes by race, education, and study. We adjusted models for sex, dementia status, and study-specific characteristics. The results found that for baseline levels of overall cognitive performance, memory, and executive function, differences in race and education tended to be larger than between-study differences and consistent across studies. This pattern did not hold for rate of cognitive decline: effects of education and race/ethnicity on cognitive change were not consistently observed across studies, and when present were small, with racial/ethnic minorities and those with lower education declining at faster rates. In this diverse set of datasets, non-Hispanic Whites and those with higher education had substantially higher baseline cognitive test scores. However, differences in the rate of cognitive decline by race/ethnicity and education did not follow this pattern. This study suggests that baseline test scores and longitudinal change have different determinants, and future studies to examine similarities and differences of causes of cognitive decline in racially/ethnically and educationally diverse older groups is needed.

Educational Inequalities in Health Behaviors at Midlife: Is There a Role for Early-life Cognition?

Education is a fundamental cause of social inequalities in health because it influences the distribution of resources, including money, knowledge, power, prestige, and beneficial social connections, that can be used in situ to influence health. Recent studies have highlighted early-life cognition as commonly indicating the propensity for educational attainment and determining health and age of mortality. Health behaviors provide a plausible mechanism linking both education and cognition to later-life health and mortality. We examine the role of education and cognition in predicting smoking, heavy drinking, and physical inactivity at midlife using data from the Wisconsin Longitudinal Study (N = 10,317), National Survey of Health and Development (N = 5,362), and National Childhood Development Study (N = 16,782). Adolescent cognition was associated with education but was inconsistently associated with health behaviors. Education, however, was robustly associated with improved health behaviors after adjusting for cognition. Analyses highlight structural inequalities over individual capabilities when studying health behaviors.

Age-related decline in verbal learning is moderated by demographic factors, working memory capacity, and presence of amnestic mild cognitive impairment

Age-related memory changes are highly varied and heterogeneous. The study examined the rate of decline in verbal episodic memory as a function of education level, auditory attention span and verbal working memory capacity, and diagnosis of amnestic mild cognitive impairment (a-MCI). Data were available on a community sample of 653 adults aged 17-86 years and 70 patients with a-MCI recruited from eight broad geographic areas in Greece and Cyprus. Measures of auditory attention span and working memory capacity (digits forward and backward) and verbal episodic memory (Auditory Verbal Learning Test [AVLT]) were used. Moderated mediation regressions on data from the community sample did not reveal significant effects of education level on the rate of age-related decline in AVLT indices. The presence of a-MCI was a significant moderator of the direct effect of Age on both immediate and delayed episodic memory indices. The rate of age-related decline in verbal episodic memory is normally mediated by working memory capacity. Moreover, in persons who display poor episodic memory capacity (a-MCI group), age-related memory decline is expected to advance more rapidly for those who also display relatively poor verbal working memory capacity.

Executive functioning as a mediator of the relationship between premorbid verbal intelligence and health risk behaviors in a rural-dwelling cohort: a Project FRONTIER study

Limited research is available regarding the impact of neuropsychological functioning on health risk behaviors in rural-dwelling elderly populations. This cross-sectional study examined the relationships between estimated premorbid verbal IQ (AMNART), executive functioning impairment (EXIT25), and health risk behaviors including alcohol use (AUDIT), smoking, compliance with recommended cancer screenings, and obesity (BMI). The total sample included 456 English-speaking adults and older adults of non-Hispanic White and Hispanic origin seen as part of an ongoing study of rural cognitive aging, Project FRONTIER. Regression analyses revealed significant independent effects of AMNART and EXIT25 on most health risk behaviors, and supported the hypothesized mediating role of EXIT25 on the relationships between AMNART and smoking, cancer screenings, and BMI in both cognitively impaired and healthy subgroups. This study clarifies the relationships between executive functioning, premorbid IQ, and health risk behaviors in diverse groups, and confirms that premorbid IQ represents an important determinant of health behaviors and neurocognitive outcomes.

Perceived discrimination and cognition in older African Americans

Existing evidence suggests that psychosocial stress is associated with cognitive impairment in older adults. Perceived discrimination is a persistent stressor in African Americans that has been associated with several adverse mental and physical health outcomes. To our knowledge, the association of discrimination with cognition in older African Americans has not been examined. In a cohort of 407 older African Americans without dementia (mean age = 72.9; SD = 6.4), we found that a higher level of perceived discrimination was related to poorer cognitive test performance, particularly episodic memory (estimate = -0.03; SE = .013; p < .05) and perceptual speed tests (estimate = -0.04; SE = .015; p < .05). The associations were unchanged after adjusting for demographics and vascular risk factors, but were attenuated after adjustment for depressive symptoms (Episodic memory estimate = -0.02; SE = 0.01; Perceptual speed estimate = -0.03; SE = 0.02; both p's = .06). The association between discrimination and several cognitive domains was modified by level of neuroticism. The results suggest that perceived discrimination may be associated with poorer cognitive function, but does not appear to be independent of depressive symptoms. (JINS, 2012, 18, 1-10).

Indicators of childhood quality of education in relation to cognitive function in older adulthood

BACKGROUND

The association between years of education and cognitive function in older adults has been studied extensively, but the role of quality of education is unknown. We examined indicators of childhood educational quality as predictors of cognitive performance and decline in later life.

METHODS

Participants included 433 older adults (52% African American) who reported living in Alabama during childhood and completed in-home assessments of cognitive function at baseline and 4 years later. Reports of residence during school years were matched to county-level data from the 1935 Alabama Department of Education report for school funding (per student), student-teacher ratio, and school year length. A composite measure of global cognitive function was utilized in analyses. Multilevel mixed effects models accounted for clustering of educational data within counties in examining the association between cognitive function and the educational quality indices.

RESULTS

Higher student-teacher ratio was associated with worse cognitive function and greater school year length was associated with better cognitive function. These associations remained statistically significant in models adjusted for education level, age, race, gender, income, reading ability, vascular risk factors, and health behaviors. The observed associations were stronger in those with lower levels of education (≤12 years), but none of the education quality measures were related to 4-year change in cognitive function.

CONCLUSIONS

Educational factors other than years of schooling may influence cognitive performance in later life. Understanding the role of education in cognitive aging has substantial implications for prevention efforts as well as accurate identification of older adults with cognitive impairment.

Influence of reading ability on neuropsychological performance in African American elders

Use of normative data stratified by education may result in misclassification of African American older adults because reading ability, an estimate of educational attainment, is lower than reported years of education for some African American elders. This study examined the contribution of reading ability versus education to neuropsychological test performance in 86 community-dwelling African American elders ages 56-91 with 8-18 years of education. Hierarchical multiple regression analyses revealed that reading ability, but not education, was significantly associated with performances on the Trail Making Test, Controlled Oral Word Association Test, Animal Naming, Digit Span, and the Stroop test. Reading ability was not significantly related to performances on measures of memory. Medium to large effect sizes (Cohen's d = 0.58-1.41) were found when comparing mean performances on neuropsychological measures in groups with low versus high reading scores. Results indicate that reading ability contributes beyond educational attainment to performances on some neuropsychological measures among African American elders. These findings have implications for reducing misclassification among minority populations through the use of appropriate normative data.

The relationship between education level and mini-mental state examination domains among older Mexican Americans

To study the effect of education and language of response at the interview on performance in the Mini-Mental State Examination (MMSE) domains, we studied 2861 Mexican Americans aged 65 and older from the Hispanic Established Populations for Epidemiologic Studies of the Elderly (EPESE) followed from 1993 to 1994 until 2004 to 2005. The MMSE was examined as total score (0-30) or divided into 2 global domains: (1) no-memory (score 0-24): Orientation, attention, and language; and (2) memory (score 0-6): working and delayed memory. Mean age and total MMSE were 72.7 years and 24.6 at baseline, and 81.7 years and 20.5 at 11 years of follow-up. Spanish-speaking participants had less education (4.1 vs 7.4 years, P < .0001), they had significantly higher adjusted mean scores for memory, no-memory, and total MMSE compared with English-speaking participants. In multivariate longitudinal analyses, participants with more years of education performed better than those with less education, especially in total MMSE and no-memory domain. Spanish-speaking participants with 4 to 6 years of education had higher memory scores than those speaking English (estimate 0.40, standard error [SE] = 0.14, P < .001), 7 to 11 (estimate 0.27, standard error = 0.13, P < .01) or 12+ (estimate 0.44, standard error = 0.13, P < .001). Results suggest that cultural factors and variables related to preferred language use determined variations in MMSE performance. Because the memory domain of the MMSE is less affected by education, it may be used along with other cognitive tests for early detection of cognitive decline in older populations with low education.

A Comparison of Self-Rated and Objectively Measured Successful Aging Constructs in an Urban Sample of African American Older Adults

Sixty-seven (N = 67) urban African American older adults were divided into successful and nonsuccessful aging groups based on objective MacArthur (i.e., physical and cognitive functioning) and on self-rated health criteria. Only 30% of the sample met objective MacArthur criteria for successful aging compared to 63% who rated themselves as successful. Self-rated successful aging was best predicted by regular exercise, whereas objective successful aging was best predicted by demographic characteristics and cognition. Reading ability mediated the relationship between both education and cognition to objectively defined success. Finally, objective successful aging was related to quantity and quality of education, whereas self-rated successful aging was related to a wider variety of variables. Defining successful aging on objective factors alone may limit our understanding of successful aging in urban African American older adults.

Normative performance on an executive clock drawing task (CLOX) in a community-dwelling sample of older adults

The CLOX is a clock drawing test used to screen for cognitive impairment in older adults, but there is limited normative data for this measure. This study presents normative data for the CLOX derived from a diverse sample of 585 community-dwelling older adults with complete cognitive data at baseline and 4-year follow-up. Participants with evidence of baseline impairment or substantial 4-year decline on the Mini-Mental State Examination were excluded from the normative sample. Spontaneous clock drawing (CLOX1) and copy (CLOX2) performances were stratified by age group and reading ability from the Wide Range Achievement Test, 3rd edition (WRAT-3). Lowest mean CLOX scores were observed for the oldest age group (75+ years old) with the lowest WRAT-3 reading scores. For all groups, average scores were higher for CLOX2 than CLOX1. These normative data may be helpful to clinicians and researchers for interpreting CLOX performance in older adults with diverse levels of reading ability.

Effects of race and socioeconomic status on the relative influence of education and literacy on cognitive functioning

Previous research has shown that reading ability is a stronger predictor of cognitive functioning than years of education, particularly for African Americans. The current study was designed to determine whether the relative influence of literacy and education on cognitive abilities varies as a function of race or socioeconomic status (SES). We examined the unique influence of education and reading scores on a range of cognitive tests in low- and higher-SES African Americans and Whites. Literacy significantly predicted scores on all but one cognitive measure in both African American groups and low-SES Whites, while education was not significantly associated with any cognitive measure. In contrast, both education and reading scores predicted performance on many cognitive measures in higher-SES Whites. These findings provide further evidence that reading ability better predicts cognitive functioning than years of education and suggest that disadvantages associated with racial minority status and low SES affect the relative influence of literacy and years of education on cognition.

Health literacy and cognitive performance in older adults

OBJECTIVES

To study the relationship between health literacy and memory and verbal fluency in older adults.

DESIGN

Cross-sectional cohort.

SETTING

Twenty senior centers and apartment buildings in New York, New York.

PARTICIPANTS

Independently living, English- and Spanish-speaking adults aged 60 and older (N=414).

MEASUREMENTS

Health literacy was measured using the Short Test of Functional Health Literacy in Adults (S-TOFHLA). The associations between S-TOFHLA scores and immediate and delayed recall (Wechsler Memory Scale II), verbal fluency (Animal Naming), and global cognitive function (Mini-Mental State Examination, MMSE) were modeled using multivariable logistic and linear regression.

RESULTS

Health literacy was inadequate in 24.3% of participants. Impairment of immediate recall occurred in 20.4%; delayed recall, 15.0%; verbal fluency, 9.9%; and MMSE, 17.4%. Abnormal cognitive function was strongly associated with inadequate health literacy: immediate recall (adjusted odds ratio (AOR)=3.44, 95% confidence interval (CI)=1.71-6.94, P<.001), delayed recall (AOR=3.48, 95% CI=1.58-7.67, P=.002), and verbal fluency (AOR=3.47, 95% CI=1.44-8.38, P=.006). These associations persisted in subgroups that excluded individuals with normal age-adjusted MMSE scores.

CONCLUSION

Memory and verbal fluency are strongly associated with health literacy, independently of education and health status, even in those with subtle cognitive dysfunction. Reducing the cognitive burden of health information might mitigate the detrimental effects of limited health literacy in older adults. Research that examines the effect of materials modified to older adults' cognitive limitations on health literacy and health outcomes is needed.

FAS and CFL forms of verbal fluency differ in difficulty: a meta-analytic study

The Controlled Oral Word Association (COWA) Test is a brief and sensitive measure of executive cognitive dysfunction. There are two commonly used forms of the test, one using the letters F, A, and S, and the other using C, F, and L. This study examines the relative difficulty of the two forms using a meta-analytic approach that includes multiple samples of normal individuals. The effects of age, education, gender composition, exclusion criteria, and age of study are also examined. Results indicate that the CFL form of the test is more difficult and that age, education, and the use of strict exclusion criteria influence performance. Performance is more variable for the FAS form, and age and age of study influence performance variability.

Mild cognitive dysfunction: an epidemiological perspective with an emphasis on African Americans

This review begins with a historical accounting of the evolution of the concept of mild cognitive dysfunction, including nomenclature and criteria from Kral to Petersen. A critical analysis of the main elements relating to assessment and diagnosis of mild cognitive dysfunction is provided. Methodological limitations in design, measurement, and characterization, especially as they relate to older African Americans, are identified. Data from a 15-year longitudinal study of community-dwelling African Americans in Indianapolis, Indiana, indicate a 23% prevalence of all-cause mild cognitive dysfunction, with approximately 25% progressing to dementia in 2 years and another 25% reverting to normal cognition in the same interval. Factors contributing to this longitudinal variability in outcomes are reviewed, including the role of medical health factors. The review closes with suggestions for next steps in the epidemiological research of mild cognitive impairment.