Advantages and disadvantages of separate norms for African Americans

Limitations of neuropsychological measures and normative data are exposed as use of these measures among culturally and linguistically different people expands in clinical and research settings. Several different tactics to solve the problem of poor specificity of cognitive measures among ethnic minorities have emerged in the literature; however, the development of separate racial/ethnic group norms has been the predominant approach. This commentary addresses the advantages and disadvantages of establishing separate norms for African Americans. Another approach, involving the deconstruction of race and education, may help to clarify the independent influences of race, culture, quality of education, and socioeconomic status on cognition and neuropsychological test performance.     

Advantages and Disadvantages of Separate Norms for African Americans

ABSTRACT

Limitations of neuropsychological measures and normative data are exposed as use of these measures among culturally and linguistically different people expands in clinical and research settings. Several different tactics to solve the problem of poor specificity of cognitive measures among ethnic minorities have emerged in the literature; however, the development of separate racial/ethnic group norms has been the predominant approach. This commentary addresses the advantages and disadvantages of establishing separate norms for African Americans. Another approach, involving the deconstruction of race and education, may help to clarify the independent influences of race, culture, quality of education, and socioeconomic status on cognition and neuropsychological test performance.     

Sex/gender differences in cognitive trajectories vary as a function of race/ethnicity

IntroductionThe present study sought to determine whether cognitive trajectories differ between men and women across and within racial/ethnic groups.MethodsParticipants were 5258 non-Hispanic White (NHW), Black, and Hispanic men and women in the Washington/Hamilton Heights-Inwood Columbia Aging Project who were administered neuropsychological tests of memory, language, and visuospatial abilities at 18- to 24-month intervals for up to 25 years. Multiple-group latent growth curve modeling examined trajectories across sex/gender by race/ethnicity.ResultsAfter adjusting for age and education, the largest baseline differences were between NHW men and Hispanic women on visuospatial and language, and between NHW women and Black men on memory. Memory and visuospatial decline was steeper for Black women compared with Hispanic men and NHW women, respectively.DiscussionThis study takes an important first step in understanding interactions between race/ethnicity and sex/gender on cognitive trajectories by demonstrating variability in sex/gender differences across race/ethnicity.     

Neuropsychological impairment in racial/ethnic minorities with HIV infection and low literacy levels: effects of education and reading level in participant characterization.

Educational attainment is an important factor in the interpretation of cognitive test scores but years of education are not necessarily synonymous with educational quality among racial/ethnic minority populations. This study investigated the comparability of educational attainment with reading level and examined whether discrepancies in education and reading level accounted for differences in neuropsychological test performance between HIV+ racial/ethnic minority and nonminority participants. Study participants (N=200) were derived from the Manhattan HIV Brain Bank (MHBB) where 50% of the cohort had < or =8th grade reading level but only 5% had < or =8 years of education. Significantly lower reading ability and education was found among African Americans and Hispanics, and these participants were more likely to have discrepant reading and education levels compared to non-Hispanic Whites. Discrepancy in reading and education level was associated with worse neuropsychological performance while racial/ethnic minority status was not. As years of schooling overestimated racial/ethnic minority participants' educational quality, standard norms based on education may inflate impairment rates among racial/ethnic minorities. Identifying appropriate normative standards is and will continue to be important in the detection of cognitive impairment in racial/ethnic minorities with HIV.     

Perspective on race and ethnicity in Alzheimer's disease research

There are adequate scientific, public health, and ethical justifications for studying Alzheimer's disease (AD) in persons of varying race and ethnicity, but to be meaningful variables, race and ethnicity must be examined in context. The complex interactions between race, ethnicity, lifestyle, and environmental factors, such as climate and diet, require that future studies of AD in specific racial or ethnic groups attend to measures of racial/ethnic homogeneity and the assessment of the environment and the elements that comprise the ethnicity of groups under study. Instead of arbitrarily selecting specific racial or ethnic groups in the hope of finding important differences, it may be in the long run less costly and more efficient to recruit families with highly positive (or negative) family histories, to search within these groups for possible racial or ethnic differences, and to investigate the possible racial or ethnic reasons for those differences.     

Kids are People (Who end up in Court) too!

Abstract

Objective: The aim of this study was to examine test performance on a cross-cultural neuropsychological test battery for assessment of middle-aged and elderly ethnic minority and majority populations in western Europe, and to present preliminary normative data. Method: The study was a cross-sectional multi-center study. Tests in the European Cross-Cultural Neuropsychological Test Battery (CNTB) cover several cognitive domains, including global cognitive function, memory, executive functions, and visuospatial functions. Results: A total of 330 participants were included: 14 Moroccan, 45 Pakistani/Indian Punjabi, 41 Polish, 66 Turkish, and 19 former Yugoslavian minority participants, and 145 western European majority participants. Significant differences between ethnic groups were found on most CNTB measures. However, ethnic groups differed greatly in demographic characteristics and differences in test scores were mainly related to educational differences, explaining an average of 15% of the variance. Preliminary multicultural CNTB normative data dichotomized by education and age were constructed using overlapping cells. Applying this normative data across the whole sample resulted in an acceptable number of participants scoring in the impaired range across all ethnic groups. Factor analyses found the CNTB to have a stable and clinically meaningful factor structure. Conclusions: The CNTB represents the first European joint effort to establish neuropsychological measures appropriate for ethnic minority populations in western Europe. The CNTB can be applied in approximately 60 min, covers several cognitive domains, and appears appropriate for assessment of the targeted populations. However, due to the small sample size in some ethnic groups further studies are needed replicate and support this.     

Quality, and not just quantity, of education accounts for differences in psychometric performance between african americans and white non-hispanics with Alzheimer's disease

The effect of race on cognitive test performance in the evaluation of Alzheimer's disease (AD) remains controversial. One factor that may contribute substantially to differences in cognitive test performance in diverse populations is education. The current study examined the extent to which quality of education, even after controlling for formal years of education, accounts for differences in cognitive performance between African Americans and White Non-Hispanics (WNHs). The retrospective cohort included 244 patients diagnosed with AD who self-identified as African Americans (n = 51) or WNHs (n = 193). The Wechsler Test of Adult Reading (WTAR) was used as an estimate of quality of education. In an analysis that controlled for traditional demographics, including age, sex, and years of formal education, African Americans scored significantly lower than WNHs on the Mini-Mental State Examination, as well as on neuropsychological tests of memory, attention, and language. However, after also adjusting for reading level, all previously observed differences were significantly attenuated. The attenuating effect remained even after controlling for disease severity, indicating that reading scores are not confounded by severity of dementia. These findings suggest that quality, and not just quantity, of education needs to be taken into account when assessing cognitive performance in African Americans with AD.     

Secular trends in cognitive trajectories of diverse older adults

IntroductionThis study aimed to determine if later birth year influences trajectory of age-related cognitive decline across racial/ethnic groups and to test whether years of school, childhood socioeconomic status, and cardiovascular disease burden explain such secular trends.MethodsWe compared cognitive trajectories of global cognition and subdomains in two successive racially/ethnically and educationally diverse birth cohorts of a prospective cohort study.ResultsLater birth year was associated with higher initial cognitive levels for Whites and Blacks, but not Hispanics. Later birth year was also associated with less rapid rate of decline in all three racial/ethnic groups. More years of education, higher childhood socioeconomic status, and, to a smaller extent, greater cardiovascular disease burden accounted for higher intercepts in the later-born cohort, but did not account for attenuated slope of cognitive decline.DiscussionLater birth year is related to a slower rate of age-related decline in some cognitive domains in some racial/ethnic groups. Our analyses suggest that racial/ethnic and social inequalities are part of the mechanisms driving secular trends in cognitive aging and dementia.     

Comparing cerebral perfusion in Alzheimer's disease and Parkinson's disease dementia: an ASL-MRI study

Emerging evidence suggests that Alzheimer''s disease (AD) and Parkinson''s disease dementia (PDD) share neurodegenerative mechanisms. We sought to directly compare cerebral perfusion in these two conditions using arterial spin labeling magnetic resonance imaging (ASL-MRI). In total, 17 AD, 20 PDD, and 37 matched healthy controls completed ASL and structural MRI, and comprehensive neuropsychological testing. Alzheimer''s disease and PDD perfusion was analyzed by whole-brain voxel-based analysis (to assess absolute blood flow), a priori specified region of interest analysis, and principal component analysis (to generate a network differentiating the two groups). Corrections were made for cerebral atrophy, age, sex, education, and MRI scanner software version. Analysis of absolute blood flow showed no significant differences between AD and PDD. Comparing each group with controls revealed an overlapping, posterior pattern of hypoperfusion, including posterior cingulate gyrus, precuneus, and occipital regions. The perfusion network that differentiated AD and PDD groups identified relative differences in medial temporal lobes (AD<PDD) and right frontal cortex (PDD<AD). In conclusion, the pattern of cerebral hypoperfusion is very similar in AD and PDD. This suggests closely linked mechanisms of neurodegeneration mediating the evolution of dementia in both conditions.     

Prevalence, patterns, and correlates of co-occurring substance use and mental disorders in the United States: variations by race/ethnicity

ObjectiveThis study examines racial/ethnic differences in the prevalence, patterns, and correlates of co-occurring substance use and mental disorders (COD) among Whites, Blacks, Latinos, and Asians using data from the Collaborative Psychiatric Epidemiology Studies.MethodWe first estimated the prevalence of various combinations of different co-occurring depressive and anxiety disorders among respondents with alcohol, drug, and any substance use (alcohol or drug) disorders in each racial/ethnic group. We then estimated the prevalence of different patterns of onset and different psychosocial correlates among individuals with COD of different racial/ethnic groups. We used weighted linear and logistic regression analysis controlling for key demographics to test the effect of race/ethnicity. Tests of differences between specific racial/ethnic subgroups were only conducted if the overall test of race was significant.ResultsRates of COD varied significantly by race/ethnicity. Approximately 8.2% of Whites, 5.4% of Blacks, 5.8% of Latinos, and 2.1% of Asians met criteria for lifetime COD. Whites were more likely than persons in each of the other groups to have lifetime COD. Irrespective of race/ethnicity, most of those with COD reported that symptoms of mental disorders occurred before symptoms of substance use disorders. Only rates of unemployment and history of psychiatric hospitalization among individuals with COD were found to vary significantly by racial/ethnic group.ConclusionsOur findings underscore the need to further examine the factors underlying differences between minority and nonminority individuals with COD as well as how these differences might affect help seeking and utilization of substance abuse and mental health services.     

Early environmental factors, ethnicity, and adult cognitive test performance

This study was conducted to better understand cross-cultural variation in neuropsychological test performance by exploring the relationship between early environmental factors and adult neuropsychological functioning in African Americans (AA) and Caucasians (CA). Cognitive testing data and detailed retrospective early environmental histories were obtained from 100 neurologically healthy adults (75 AA, 25 CA). Results indicate that: (a) consistent with previous research, the two ethnic groups differed significantly on their cognitive test performance; (b) early environmental factors were significantly related to performance on cognitive tests; (c) the two ethnic groups demonstrated slight, but significant, differences in their early environmental histories; but (d) covarying early environmental factors did not substantially reduce the group performance in cognitive test performance. The failure of reported environmental factors to account for more of the ethnic disparity in test performance may have resulted from the inherent weakness of the retrospective assessment method (i.e., lack of precision or objectivity in participants' recollections of their early environments). These results highlight the remaining need for ethnicity specific normative data until cross-cultural variation in neuropsychological test performance is better understood.     

Phenotypic Characteristics of Autism Spectrum Disorder in a Diverse Sample of Somali and Other Children

The potential for culture to impact diagnosis of autism spectrum disorder (ASD) is high, yet remains largely unstudied. This study examined differences across racial/ethnic groups in ASD symptoms, cognitive and adaptive skills, and related behaviors in children with ASD that included a unique subgroup, children from the Somali diaspora. Somali children were more likely to have ASD with intellectual disability than children from all other racial/ethnic groups. Few differences were found in the presence of specific symptoms and behaviors across groups once IQ was controlled. Results lend support to previous studies that found higher rates of ASD intellectual disability in children of immigrants from low human resource index countries compared to other groups. Implications for future research are discussed.     

Variables moderating cultural and ethnic differences in neuropsychological assessment: the case of Hispanic Americans

Problems associated with the use of culture and ethnicity as independent variables in neuropsychological assessment research are reviewed. Culture and ethnicity are complex multidimensional constructs that have defied operational definition. There are no clear criteria for separating cultural and ethnic groups. Cognitive differences between culture and ethnic groups encourage speculations of cultural or ethnic superiority and race-norming. An alternative approach is to focus upon measurable psychological variables that differ between cultural and ethnic groups and potentially impact neuropsychological test scores. To illustrate, research with Hispanic Americans is reviewed to show that English language fluency, length of residence within the United States, years of education, and persistence of poverty all impact test performance.     

Variables Moderating Cultural and Ethnic Differences in Neuropsychological Assessment: The Case of Hispanic Americans

Problems associated with the use of culture and ethnicity as independent variables in neuropsychological assessment research are reviewed. Culture and ethnicity are complex multidimensional constructs that have defied operational definition. There are no clear criteria for separating cultural and ethnic groups. Cognitive differences between culture and ethnic groups encourage speculations of cultural or ethnic superiority and race-norming. An alternative approach is to focus upon measurable psychological variables that differ between cultural and ethnic groups and potentially impact neuropsychological test scores. To illustrate, research with Hispanic Americans is reviewed to show that English language fluency, length of residence within the United States, years of education, and persistence of poverty all impact test performance.     

Distributed functional connectivity predicts neuropsychological test performance among older adults

Neuropsychological test is an essential tool in assessing cognitive and functional changes associated with late‐life neurocognitive disorders. Despite the utility of the neuropsychological test, the brain‐wide neural basis of the test performance remains unclear. Using the predictive modeling approach, we aimed to identify the optimal combination of functional connectivities that predicts neuropsychological test scores of novel individuals. Resting‐state functional connectivity and neuropsychological tests included in the OASIS‐3 dataset (n = 428) were used to train the predictive models, and the identified models were iteratively applied to the holdout internal test set (n = 216) and external test set (KSHAP, n = 151). We found that the connectivity‐based predicted score tracked the actual behavioral test scores (r = 0.08–0.44). The predictive models utilizing most of the connectivity features showed better accuracy than those composed of focal connectivity features, suggesting that its neural basis is largely distributed across multiple brain systems. The discriminant and clinical validity of the predictive models were further assessed. Our results suggest that late‐life neuropsychological test performance can be formally characterized with distributed connectome‐based predictive models, and further translational evidence is needed when developing theoretically valid and clinically incremental predictive models.     

Socioeconomic Status and Neuropsychological Functioning: Associations in an Ethnically Diverse HIV+ Cohort

Objective: There is limited research examining the relationship between socioeconomic status (SES) and neuropsychological functioning, particularly in racial/ethnic minority and HIV+ populations. However, there are complex associations between poverty, education, HIV disease, race/ethnicity, and health outcomes in the US. Method: We explored these relationships among an ethnically diverse sample of 134 HIV+ adults using a standardized SES measure (i.e., the Hollingshead scale), a comprehensive NP test battery, and a functional evaluation (i.e., Patient’s Assessment of Own Functioning Inventory and Modified Instrumental Activities of Daily Living Scale). Results: Bivariate analyses showed that adult SES was significantly, positively correlated with neuropsychological performance on specific tests within the domains of verbal fluency, attention/concentration, learning, memory, processing speed, and executive functioning, and childhood SES was significantly linked to measures of verbal fluency, processing speed, and executive functioning. In a series of linear regressions, controlling for SES significantly attenuated group differences in NP test scores between racial/ethnic minority individuals and non-Hispanic White individuals. Finally, SES scores significantly differed across HIV-Associated Neurocognitive Disorder (HAND) diagnoses. In a binary logistic regression, SES was the only independent predictor of HAND diagnosis. Conclusions: HIV+ individuals with lower SES may be more vulnerable to HIV-associated neuropsychological sequelae due to prominent health disparities, although the degree to which this is influenced by factors such as test bias remains unclear. Overall, our results suggest that SES is significantly linked to neuropsychological test performance in HIV+ individuals, and is an important factor to consider in clinical practice.     

Reading level attenuates differences in neuropsychological test performance between African American and White elders.

The current study sought to determine if discrepancies in quality of education could explain differences in cognitive test scores between African American and White elders matched on years of education. A comprehensive neuropsychological battery was administered to a sample of African American and non-Hispanic White participants in an epidemiological study of normal aging and dementia in the Northern Manhattan community. All participants were diagnosed as nondemented by a neurologist, and had no history of Parkinson's disease, stroke, mental illness, or head injury. The Reading Recognition subtest from the Wide Range Achievement Test-Version 3 was used as an estimate of quality of education. A MANOVA revealed that African American elders obtained significantly lower scores than Whites on measures of word list learning and memory, figure memory, abstract reasoning, fluency, and visuospatial skill even though the groups were matched on years of education. However, after adjusting the scores for WRAT-3 reading score, the overall effect of race was greatly reduced and racial differences on all tests (except category fluency and a drawing measure) became nonsignificant. These findings suggest that years of education is an inadequate measure of the educational experience among multicultural elders, and that adjusting for quality of education may improve the specificity of certain neuropsychological measures.     

Diversity and disparity in dementia: the impact of ethnoracial differences in Alzheimer disease

Debate exists regarding differences in the prevalence of Alzheimer disease (AD) in African Americans and Hispanics in the United States, with some evidence suggesting that the prevalence of AD may be considerably higher in these groups than in non-Hispanic whites. Despite this possible disparity, patients of minority ethnoracial groups often receive delayed diagnosis or inadequate treatment for dementia. This review investigates these disparities by conceptualizing the dementia disease process as a product of both biological and cultural factors. Ethnoracial differences in biological risk factors, such as genetics and cardiovascular disease, may help to explain disparities in the incidence and prevalence of AD, whereas race-specific cultural factors may impact diagnosis and treatment. Cultural factors include differences in perceptions about what is normal aging and what is not, lack of adequate access to medical care, and issues of trust between minority groups and the medical establishment. The diagnosis of AD in diverse populations may also be complicated by racial biases inherent in cognitive screening tools widely used by clinicians, but controlling for literacy level or using savings scores in psychometric analyses has the potential to mitigate these biases. We also suggest that emerging biomarker-based diagnostic tools may be useful in further characterizing diverse populations with AD. Recognizing the gap in communication that exists between minority communities and the medical research community, we propose that education and outreach are a critical next step in the effort to understand AD as it relates to diverse populations.     

Race in the "decade of the brain"

Despite NIMH efforts to facilitate the study of women and minorities in federally funded schizophrenia research, there is a significant lack of information about race differences in brain morphology and neuropsychological function in schizophrenia. A review of three major psychiatric journals between 1994 and 1996 revealed that only 14 (2.8%) of 502 schizophrenia articles reported the results of race analyses. Only 84 (16.7%) even reported the racial composition of the study sample. The study of race differences in schizophrenia, although fraught with methodological complexity and social/political tension, is necessary to prevent inappropriate generalization of research results across racial groups.     

Relationship of ethnicity, age, education, and reading level to speed and executive function among HIV+ and HIV- women: the Women's Interagency HIV Study (WIHS) Neurocognitive Substudy

Use of neuropsychological tests to identify HIV-associated neurocognitive dysfunction must involve normative standards that are well suited to the population of interest. Norms should be based on a population of HIV-uninfected individuals as closely matched to the HIV-infected group as possible and must include examination of the potential effects of demographic factors on test performance. This is the first study to determine the normal range of scores on measures of psychomotor speed and executive function among a large group of ethnically and educationally diverse HIV-uninfected, high-risk women, as well as their HIV-infected counterparts. Participants (n?=?1,653) were administered the Trail Making Test Parts A and B (Trails A and Trails B), the Symbol Digit Modalities Test (SDMT), and the Wide Range Achievement Test-3 (WRAT-3). Among HIV-uninfected women, race/ethnicity accounted for almost 5% of the variance in cognitive test performance. The proportions ofvariance in cognitive test performance accounted for by age (13.8%), years of school (4.1%), and WRAT-3 score (11.5%) were each significant, but did not completely account for the effect of race (3%). HIV-infected women obtained lower scores than HIV-uninfected women on time to complete Trails A and B, SDMT total correct, and SDMT incidental recall score, but after adjustment for age, years of education, racial/ethnic classification, and reading level, only the difference on SDMT total correct remained significant. Results highlight the need to adjust for demographic variables when diagnosing cognitive impairment in HIV-infected women. Advantages of demographically adjusted regression equations developed using data from HIV-uninfected women are discussed.