Socioeconomic Status, Race/Ethnicity, and Unexpected Variation in Dementia Classification in Longitudinal Survey Data

Moderating Role of Neighborhood Environment in the Associations Between Hearing Loss and Cognitive Challenges Among Older Adults: Evidence From US National Study

This study examined the associations between hearing loss and cognitive challenges among community-dwelling older adults and whether neighborhood characteristics (physical disorder and low social cohesion) moderated the associations. Cross-sectional national data from Round 11 of the National Health and Aging Trends Study were adopted (N = 2,515). Multinomial logistic regressions were used to examine associations among variables and interactive analyses were conducted to examine moderating effects. Results indicated significant relationships between the experience of hearing loss and possible dementia and between severe or profound hearing loss and probable dementia. Interactive models suggested that residing in neighborhoods with physical disorder and low social cohesion were negatively associated with possible dementia among older adults with moderate and severe or profound hearing loss, respectively, compared to those without hearing loss. Findings underscore the necessity of environmental and social interventions to enhance cognitive health among older adults with varying degrees of hearing challenges.

Under-Diagnosis of Dementia with Lewy Bodies in Individuals Racialized as Black: Hypotheses Regarding Potential Contributors

Dementia with Lewy bodies (DLB) is one of the most common degenerative dementias after Alzheimer's disease (AD) dementia. DLB is under-diagnosed across populations but may be particularly missed in older Black adults. The object of this review was to examine key features of DLB and potential associations with race in order to hypothesize why DLB may be under-diagnosed in Black adults in the U.S. In terms of dementia, symptoms associated with high rates of co-pathology (e.g., AD, vascular disease) in older Black adults may obscure the clinical picture that might suggest Lewy body pathology. Research also suggests that clinicians may be predisposed to give AD dementia diagnoses to Black adults, potentially missing contributions of Lewy body pathology. Hallucinations in Black adults may be misattributed to AD or primary psychiatric disease rather than Lewy body pathology. Research on the prevalence of REM sleep behavior in diverse populations is lacking, but REM sleep behavior disorder could be under-diagnosed in Black adults due to sleep patterns or reporting by caregivers who are not bed partners. Recognition of parkinsonism could be reduced in Black adults due to clinician biases, cultural effects on self-report, and potentially underlying differences in the frequency of parkinsonism. These considerations are superimposed on structural and systemic contributions to health (e.g., socioeconomic status, education, structural racism) and individual-level social exposures (e.g., social interactions, discrimination). Improving DLB recognition in Black adults will require research to investigate reasons for diagnostic disparities and education to increase identification of core symptoms in this population.

Understanding Racial Disparities in Dementia Prevalence Among Veterans

Background

Black and Hispanic older adults have greater incidence of Alzheimer's disease and related dementias relative to White adults, but factors underlying these disparities are not well understood, limiting the ability to address them.

Objective

To determine the impact of demographics, cardiovascular disease (CVD) and risk factors, social determinants of health (SDOH), and neuropsychiatric risk factors on racial/ethnic disparities in dementia risk among Veterans.

Methods

We examined a random sample of 1,579,919 older Veterans (age ≥55) without dementia who received care from the VHA from October 1, 1999 to September 30, 2021. All variables were extracted from national VHA data. We used Cox proportional hazard regression models to examine change in variance in risk of dementia across racial/ethnic groups.

Results

During follow up (mean 11.1 years), 13% of Veterans developed dementia. Relative to White Veterans, the adjusted hazard ratios (AHRs) for developing dementia in sex-adjusted models with age as timescale were 1.65 (95% CI, 1.63-1.67) for Black Veterans and 1.50 (95% CI, 1.44-1.56) for Hispanic Veterans. In the model examining CVD and risk factors, AHRs were 1.53 (95% CI, 1.50-1.55) for Black Veterans and 1.38 (95% CI, 1.33-1.44) for Hispanic Veterans. In the model examining SDOH, AHRs were 1.46 (95% CI, 1.43-1.49) for Black Veterans and 1.34 (95% CI, 1.29-1.40) for Hispanic Veterans.

Conclusions

SDOH and CVD and risk factors accounted for the greatest amount of variance in racial/ethnic disparities in dementia risk. Cardiovascular disease and SDOH are strong possible targets for interventions designed to reduce these disparities.

Health Disparities in Cognitive Impairment and Dementia: Role of Social Strain, Depression, and C-Reactive Protein

We investigated the association of social strain from friends, depression, and systemic inflammation (C-Reactive Protein [CRP]) with cognitive impairment without dementia (CIND) and dementia among 9,262 participants (age ≥ 65). We analyzed data from the Health Retirement Study (HRS), performing Chi-squared and logistic regression analyses. Measures included the 27-point HRS cognition scale, social strain scale, Center for Epidemiological Studies Depression scale, and dried-blood CRP levels. Black and Hispanic participants had a significantly increased dementia risk (OR = 2.69 and OR = 2.54). Black participants also had a high risk of CIND (OR = 2.80), but no association of Hispanic participants with CIND. Increased social strain from friends and depression were significantly associated with CIND (OR = 1.50 and OR = 1.44) and dementia (OR = 1.57 and OR = 1.78). Elevated CRP levels were only linked to CIND risk (OR = 1.03), not dementia. Early detection and interventions targeting social strain, depression, and CRP levels may help promote cognitive functioning in older adults.