Ethnicity and cognitive performance among older African Americans, Japanese Americans, and Caucasians: the role of education

Predictors of cognitive decline in a multi-racial sample of midlife women: A longitudinal study

Objective: Hypertension, diabetes, depressive symptoms, and smoking are predictors of cognitive decline in late life. It is unknown if these risk factors are associated with cognition during midlife or if the associations between these risk factors and cognition vary by race. This longitudinal study examined (a) risk factors for decline in episodic memory, processing speed, and working memory in midlife women and (b) if the associations between risk factors and cognitive decline were moderated by race. Method: Participants (aged 42-52) were European American (n = 1,000), African American (n = 516), and Asian American (n = 437) women from the Study of Women's Health Across the Nation. Two-level hierarchical linear models tested risk factors, race, and their interactions as predictors of cognitive change over time. Results: African Americans had poorer baseline episodic memory, processing speed, and working memory and greater episodic memory decline compared to European Americans. Asian Americans had poorer episodic memory and working memory, but better processing speed than European Americans. Depressive symptoms were associated with poorer episodic memory and processing speed at baseline; further, diabetes was associated with poorer processing speed at baseline. Greater depressive symptoms were associated with poorer episodic memory at baseline for African Americans but not European Americans. Conclusions: Our study results highlight racial disparities in cognition during midlife. Depressive symptoms may be particularly detrimental to the cognitive health of African Americans. Clinical and public health interventions for healthy cognitive aging should be tailored to the unique risks of racial groups. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Alzheimer's Disease and its Related Dementias among Asian Americans, Native Hawaiians, and Pacific Islanders: A Scoping Review

BACKGROUND

The Asian American, Native Hawaiian, and Pacific Islander (AANHPI) aging population is rapidly growing and the burden of Alzheimer's disease and its related dementias (ADRD) will likely mirror this demographic growth. AANHPIs face significant barriers in obtaining timely ADRD diagnosis and services; yet little is known about ADRD in this population.

OBJECTIVE

The study objective is to conduct a systematic review on the published literature on ADRD among AANHPIs to identify gaps and priorities to inform future research and action plans.

METHODS

The systematic review was conducted following the PRISMA Protocol for Systematic Reviews. Co-author (TR), an experienced Medical Librarian, searched PubMed, EMBASE, PsycINFO, Cochrane Central of Clinical Trials, Ageline, and Web of Science for peer-reviewed articles describing ADRD among AANHPIs. The search was not limited by language or publication date. Each citation was reviewed by two trained independent reviewers. Conflicts were resolved through consensus.

RESULTS

The title/abstract and full texts of 1,447 unique articles were screened for inclusion, yielding 168 articles for analysis. Major research topics included prevalence, risk factors, comorbidities, interventions and outreach, knowledge and attitudes, caregiving, and detection tools. A limited number of studies reported on national data, on NHPI communities generally, and on efficacy of interventions targeting AANHPI communities.

CONCLUSION

To our knowledge, this is the first systematic review on ADRD among AANHPI populations. Our review provides a first step in mapping the extant literature on ADRD among this underserved and under-researched population and will serve as a guide for future research, policy, and intervention.

The MATRICS Consensus Cognitive Battery (MCCB): Co-norming and standardization in China

MATRICS Consensus Cognitive Battery (MCCB), packaging 10 tests selected from more than 90 nominated tests, is a method developed by the Measurement and Treatment Research to Improve Cognition in Schizophrenia (MATRICS) group to evaluate the efficacy of treatments targeting cognitive impairments in schizophrenia. MCCB had been translated into a number of languages, but only the US and Spain had normative data reported. Inconsistency in translation and cultural differences make direct application of MCCB in China problematic. In this study, we administered the battery to a representative community sample based on Chinese population census in 2005 and obtained normative data. The effects of age, gender, education level, and scale of residence area on test performance were examined. The sample included 656 healthy volunteers from six sites in China. At each site, sample was stratified according to age, gender, and educational level, and scale of the area one was born in, grew up in and currently living in was recorded. We found age, gender, and education had significant effects on the normative data for MCCB in China, which are comparable to those found for the original standardized English version in the U.S. and the Spanish version in Spain. Remarkably, the residence scale effects on neuropsychological performance were significant, which should be taking into account when calculating the standardized T score for each subject. The practice effects were minor and test-retest reliability of MCCB was good, which suggests MCCB as an appropriate measure for clinical and research usage in China.

Racial differences in the association of education with physical and cognitive function in older blacks and whites

OBJECTIVES

Few studies have explicitly tested whether the health disadvantage among older blacks is consistent across the entire range of education. We examined racial differences in the cross-sectional association of education with physical and cognitive function performance in older adults.

METHODS

Participants included over 9500 blacks and whites, aged ≥ 65 years, from the Chicago Health and Aging Project {64% black, 60% women, mean age = 73.0 (standard deviation [SD] = 6.9), mean education = 12.2 (SD = 3.5)}. Physical function was assessed using 3 physical performance tests, and cognitive function was assessed with 4 performance-based tests; composite measures were created and used in analyses.

RESULTS

In multiple regression models that controlled for age, age-squared, sex, and race, and their interactions, whites and those with higher education (>12 years) performed significantly better on both functional health measures. The association of education with each indicator of functional health was similar in older blacks and whites with low levels (≤ 12 years) of education. However, at higher levels of education, there was a significantly more positive association between years of education and these functional health outcomes among blacks than whites.

DISCUSSION

Results from this biracial population-based sample in the Midwest suggest that blacks may enjoy greater returns in functional health for additional education beyond high school.

"Below average" self-assessed school performance and Alzheimer's disease in the Aging, Demographics, and Memory Study

BACKGROUND

A low level of formal education is becoming accepted as a risk factor for Alzheimer's disease (AD). Although increasing attention has been paid to differences in educational quality, no previous studies addressed participants' own characterizations of their overall performance in school. We examined whether self-assessed school performance is associated with AD beyond the effects of educational level alone.

METHODS

Participants were drawn from the population-representative Aging, Demographics, and Memory Study (ADAMS, 2000-2002). The ADAMS participants were asked about their performance in school. Possible response options included "above average," "average," or "below average." The ADAMS participants also underwent a full neuropsychological battery, and received a research diagnosis of possible or probable AD.

RESULTS

The 725 participants (mean age, 81.8 years; 59% female; 16% African-American) varied in self-assessed educational performance: 29% reported "above average," 64% reported "average," and 7% reported "below average" school performance. Participants with a lower self-assessed school performance had higher proportions of AD: 11% of participants with "above average" self-assessed performance had AD, as opposed to 12% of participants with "average" performance and 26% of participants with "below average" performance (P < 0.001). After controlling for subjects' years in school, a literacy test score (Wide-Range Achievement Test), age, sex, race/ethnicity, apolipoprotein E-epsilon4 status, socioeconomic status, and self-reported comorbidities, respondents with "below average" self-assessed school performance were four times more likely to have AD compared with those of "average" performance (odds ratio, 4.0; 95% confidence interval, 1.2-14). "Above average" and "average" self-assessed school performance did not increase or decrease the odds of having AD (odds ratio, 0.9; 95% confidence interval, 0.5-1.7).

CONCLUSIONS

We suggest an association between "below average" self-assessed school performance and AD beyond the known association with formal education. Efforts to increase cognitive reserve through better school performance, in addition to increasing the number of years of formal education in early life, may be important in reducing vulnerability throughout the life course.

Age and education effects on relationships of cognitive test scores with brain structure in demographically diverse older persons

This study examined how age and education influence the relationship between neuropsychological test scores and brain structure in demographically diverse older adults spanning the range from normal cognition to dementia. A sample of 351 African Americans, 410 Hispanics, and 458 Whites underwent neuropsychological testing. Volumetric magnetic resonance imaging (MRI) measures of total brain, white matter hyperintensity, and hippocampus were available for 79 African Americans, 102 Hispanics, and 134 Whites. The authors used latent variable modeling to examine effects of age, education, and brain volumes on test scores and determine how much variance brain volumes explained in unadjusted and age- and education-adjusted scores. Age adjustment resulted in weaker relationships of test scores with MRI variables; adjustment for ethnicity yielded stronger relationships. Education adjustment increased relationships with MRI variables in the combined sample and Hispanics, made no difference in Whites, but decreased some associations in African Americans. Results suggest that demographic adjustment is beneficial when demographic variables are strongly related to test scores independent of measures of brain structure, but adjustment has negative consequences when effects of demographic characteristics are mediated by brain structure.

Accelerated hippocampal atrophy rates in stable and progressive amnestic mild cognitive impairment

Studies suggest that smaller hippocampal volume predicts Alzheimer's disease (AD) in mild cognitive impairment (MCI). However, few studies have demonstrated decline rates in cognition and hippocampal volume in MCI subjects with stable clinical presentation. Furthermore, the effects of apolipoprotein E (ApoE) on the change rates of medial temporal structures and cognition in MCI are rarely investigated. Fifty-eight subjects with amnestic MCI and 20 normal aging elderly controls received annual neuropsychological and magnetic resonance imaging (MRI) assessments. Annual decline rates in neuropsychological test scores, hippocampal and amygdalar volumes were calculated. ApoE genotypes were examined. Nineteen (32.7%) MCI subjects converted to AD during an average 22.5-month follow-up period. The annual hippocampal atrophy rate was correlated with a decline in memory test scores. The presence of the ApoE varepsilon4 allele did not affect the change rates in neuropsychological test scores and medial temporal structures volume. Compared to subjects with stable MCI (MCI-S) and normal aging, progressive MCI (MCI-P) had the highest annual decline rates in cognition and hippocampal volume. Logistic regression analysis showed that higher annual decline rates in hippocampal volume and global cognitive test scores were associated with conversion to AD. Furthermore, although MCI-S subjects had little cognitive decline, their hippocampal atrophy rates were higher than those of normal aging controls. Therefore, accelerated hippocampal atrophy rates may be an early and important presentation in MCI subjects.

Ethnic and educational differences in cognitive test performance on mini-mental state examination in Asians

OBJECTIVE

The objective of this study is to examine ethnic differences in Mini-Mental State Examination (MMSE) test performance in discriminating between demented and nondemented elderly Asians.

METHODS

A nationally representative population sample (N = 1,092) of community-living elderly, comprising Chinese, Malays, and Indians in Singapore, was interviewed using MMSE, Geriatric Mental State, and demographic and health questionnaires.

RESULTS

There were significant ethnic differences in mean MMSE scores among Chinese (26.2), Indians (25.0), and Malays (23.6), but only in noneducated subjects. No ethnic differences in MMSE were observed in higher educated subjects. The sample proportion of subjects with dementia was 4.2% in Chinese, 9.4% in Malays, and 8.8% in Indians. Overall, MMSE discriminated well between subjects with and without dementia (cutoff: 23/24, area under the curve: 95%, sensitivity: 97.5%, specificity: 75.6%). MMSE test performance was much better in higher educated subjects (higher specificity: 85.2%). Lower specificities were shown in less educated subjects (57.3%), and in Malays (62.8%), and especially in less educated Malays (35.3%) and Indians (50.0%). Significant differences in MMSE scores in less educated subjects persisted after adjusting for differences in sociodemographic, health, and behavioral variables

CONCLUSION

Ethnic nonequivalence in MMSE test performance should be taken into account in dementia screening in Asians in less educated subjects. Known correlates of cognitive functioning did not sufficiently explain these differences.

Disparities Among Older Adults in Measures of Cognitive Function by Race or Ethnicity

This study examined racial or ethnic differences in cognitive function, cross-sectionally and longitudinally, using survey data from the Asset and Health Dynamics Among the Oldest Old. A version of the Telephone Interview for Cognitive Status (TICS), proxy assessments of cognition, and difficulties in performing daily tasks were assessed. Blacks performed below Whites on the TICS at baseline and on proxy assessments of cognition. TICS score declined with age for Whites and Blacks, with some relative gains for Blacks. At baseline, Blacks more often had difficulties in performing daily tasks, with some increase in difficulties relative to Whites with age. Differences between other groups and Whites were smaller than those between Blacks and Whites.

Education modifies the effect of apolipoprotein epsilon 4 on cognitive decline

OBJECTIVES

To assess the influence of education on the association between apolipoprotein E and cognitive change.

DESIGN

Prospective cohort.

PARTICIPANTS

HMO-based sample of 2168 non-demented community-dwelling elderly followed over 6 years.

MEASUREMENTS

Generalized estimating equations were used with the difference between baseline and follow-up cognitive abilities screening instrument (CASI) as the outcome variable.

RESULTS

At follow-up, 6% of the sample had a decline of 1.5 S.D. or greater on the CASI. Compared to individuals without an APOE4 allele, individuals with a single APOE4 allele did not have greater CASI decline. By contrast, individuals with two APOE4 alleles experienced greater decline in cognitive performance and the magnitude of that decline decreased as years of educational attainment increased. These relationships held after adjusting for age, gender, ethnicity, depression, diabetes, and history of vascular disease.

CONCLUSION

Lower education was associated with steep 4-year cognitive decline for APOE4 homozygotes but not for APOE4 heterozygotes. Potentially modifiable host factors such as education could influence the association of high-risk genotypes and cognitive decline.

Alcohol, aging, and cognitive performance: a cross-cultural comparison

This study investigated the relationship between alcohol consumption and cognitive performance in two culturally diverse community-based populations. METHODS. A cross-sectional analysis was used including Japanese Americans (n = 1,836) and Caucasians (n = 2,581) aged 65 and older. Cognitive performance was measured using the Cognitive Abilities Screening Instrument (CASI) (0 to 100 point scale) and reaction time. RESULTS. Multivariate analysis revealed significant cultural and gender differences with cognitive performance. Compared to abstainers, Caucasian drinkers scored higher than Japanese American drinkers on the CASI (adjusted means = 93.4 versus 91.6). In contrast, Japanese American drinkers scored faster than Caucasian drinkers on choice reaction time (adjusted means = 505 versus 579 milliseconds). DISCUSSION. Results showed that current drinking was associated with better cognition in both the Caucasian and Japanese American groups. Longitudinal studies are needed to support the possible protective effects of alcohol on cognition and explore whether culture may modify this apparent benefit.