Association Between Blood Pressure and Later-Life Cognition Among Black and White Individuals

Racial/Ethnic Disparities in Young Adulthood and Midlife Cardiovascular Risk Factors and Late-life Cognitive Domains: The Kaiser Healthy Aging and Diverse Life Experiences (KHANDLE) Study

BACKGROUND

Midlife cardiovascular risk factors (CVRF) increase dementia risk. Less is known about whether CVRF identified before midlife impact late-life cognition in diverse populations.

METHODS

Linear regression models examined hypertension, hyperlipidemia, and overweight/obesity at ages 30 to 59 with late-life executive function, semantic memory, verbal episodic memory, and global cognition in a cohort of Asians, blacks, Latinos, and whites (n=1127; mean age=75.8, range=65 to 98). Models adjusted for age at CVRF, age at cognitive assessment, sex, race/ethnicity, participant education, and parental education.

RESULTS

Overall, 34% had 1 CVRF at ages 30 to 59; 19% had 2+. Blacks (26%) and Latinos (23%) were more likely to have 2+ CVRF than Asians (14%) or whites (13%). Having 2+ CVRF was associated with lower global cognition [β=-0.33; 95% confidence interval (CI)=-0.45, -0.21], executive function (β=-0.26; 95% CI=-0.39, -0.13), verbal episodic memory (β=-0.34; 95% CI=-0.48, -0.20), and semantic memory (β=-0.20; 95% CI=-0.33, -0.07). Interaction by age (P=0.06) indicated overweight/obesity was negatively associated with executive function at ages 30 to 39 but not at ages 40 to 59. Race/ethnic-specific effects showed disparities in CVRF prevalence impact population disparities in late-life cognition.

CONCLUSION

Being overweight/obese in early adulthood and having 2+ CVRF in early adulthood/midlife are modifiable targets to redress racial/ethnic disparities in cognitive impairment and dementia.

Blood pressure-related differences in brain health between young African Americans and Caucasian Americans

Background

Although there are moderating effects of race on blood pressure (BP) and brain health in older adults, it is currently unknown if these race‐related differences in cardiovascular and associated brain function are also present in younger adults. The purpose of this study was to investigate the interaction between race and BP on brain health in younger African (AA) and Caucasian Americans (CA).

Methods

We studied 971 younger adults (29.1 ± 3.5 years; 180 AAs and 791 CAs) who volunteered to participate in the Human Connectome Project. Cognitive composite scores, brain volume, and cortical thickness using MRI were cross‐sectionally assessed. ANCOVA was used to examine interactions between race and mean arterial pressure (MAP) on cognitive test scores and brain structure.

Results

After controlling for age, sex, education, and BMI, there were significant Race × MAP interaction effects on cognitive composite scores and cortical thickness. Among AAs but not CAs, as MAP increased, both global cognitive performance and entorhinal cortex (ERC) thickness decreased.

Conclusions

MAP was an important moderator of racial differences in cognitive performance and ERC thickness. Our findings suggest that young AAs may carry a greater hypertension‐associated risk for cognitive brain health deficit. Interventions that address early signs of hypertension in AAs are needed to determine if the racial disparities in BP‐related brain health in late adulthood can be reduced.

Collaborative Cohort of Cohorts for COVID-19 Research (C4R) Study: Study Design

The Collaborative Cohort of Cohorts for COVID-19 Research (C4R) is a national prospective study of adults at risk for coronavirus disease 2019 (COVID-19) comprising 14 established United States (US) prospective cohort studies. For decades, C4R cohorts have collected extensive data on clinical and subclinical diseases and their risk factors, including behavior, cognition, biomarkers, and social determinants of health. C4R will link this pre-COVID phenotyping to information on SARS-CoV-2 infection and acute and post-acute COVID-related illness. C4R is largely population-based, has an age range of 18-108 years, and broadly reflects the racial, ethnic, socioeconomic, and geographic diversity of the US. C4R is ascertaining severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and COVID-19 illness using standardized questionnaires, ascertainment of COVID-related hospitalizations and deaths, and a SARS-CoV-2 serosurvey via dried blood spots. Master protocols leverage existing robust retention rates for telephone and in-person examinations, and high-quality events surveillance. Extensive pre-pandemic data minimize referral, survival, and recall bias. Data are being harmonized with research-quality phenotyping unmatched by clinical and survey-based studies; these will be pooled and shared widely to expedite collaboration and scientific findings. This unique resource will allow evaluation of risk and resilience factors for COVID-19 severity and outcomes, including post-acute sequelae, and assessment of the social and behavioral impact of the pandemic on long-term trajectories of health and aging.

Sex Differences in Cognitive Decline Among US Adults

Importance

Sex differences in dementia risk are unclear, but some studies have found greater risk for women.

Objective

To determine associations between sex and cognitive decline in order to better understand sex differences in dementia risk.

Design, Setting, and Participants

This cohort study used pooled analysis of individual participant data from 5 cohort studies for years 1971 to 2017: Atherosclerosis Risk in Communities Study, Coronary Artery Risk Development in Young Adults Study, Cardiovascular Health Study, Framingham Offspring Study, and Northern Manhattan Study. Linear mixed-effects models were used to estimate changes in each continuous cognitive outcome over time by sex. Data analysis was completed from March 2019 to October 2020.

Exposure

Sex.

Main Outcomes and Measures

The primary outcome was change in global cognition. Secondary outcomes were change in memory and executive function. Outcomes were standardized as t scores (mean [SD], 50 [10]); a 1-point difference represents a 0.1-SD difference in cognition.

Results

Among 34 349 participants, 26 088 who self-reported Black or White race, were free of stroke and dementia, and had covariate data at or before the first cognitive assessment were included for analysis. Median (interquartile range) follow-up was 7.9 (5.3-20.5) years. There were 11 775 (44.7%) men (median [interquartile range] age, 58 [51-66] years at first cognitive assessment; 2229 [18.9%] Black) and 14 313 women (median [interquartile range] age, 58 [51-67] years at first cognitive assessment; 3636 [25.4%] Black). Women had significantly higher baseline performance than men in global cognition (2.20 points higher; 95% CI, 2.04 to 2.35 points; P < .001), executive function (2.13 points higher; 95% CI, 1.98 to 2.29 points; P < .001), and memory (1.89 points higher; 95% CI, 1.72 to 2.06 points; P < .001). Compared with men, women had significantly faster declines in global cognition (-0.07 points/y faster; 95% CI, -0.08 to -0.05 points/y; P < .001) and executive function (-0.06 points/y faster; 95% CI, -0.07 to -0.05 points/y; P < .001). Men and women had similar declines in memory (-0.004 points/y faster; 95% CI, -0.023 to 0.014; P = .61).

Conclusions and Relevance

The results of this cohort study suggest that women may have greater cognitive reserve but faster cognitive decline than men, which could contribute to sex differences in late-life dementia.

Systolic Blood Pressure and Cognition in the Elderly: The Northern Manhattan Study

BACKGROUND

Increasing evidence suggests that hypertension is a risk factor for cognitive impairment and dementia. The relationship between blood pressure and cognition in a racially and ethnically diverse population remains unclear.

OBJECTIVE

To study association of blood pressure with cognition cross-sectionally and longitudinally in the elderly.

METHODS

Participants are stroke-free individuals from the racially and ethnically diverse Northern Manhattan Study (NOMAS) (n = 1215). General linear models are constructed to examine blood pressure in relation to cognition cross-sectionally and longitudinally at a five-year follow-up.

RESULTS

We found a cross-sectional association of systolic blood pressure (SBP) with word fluency/semantic memory, executive function, and processing speed/visual motor integration (VMI) function. This association was independent of demographics, vascular risk factors, white matter hyperintensity volume (WMHV), and carotid intima-media thickness (cIMT). The cross-sectional association of SBP with processing speed/VMI and executive function was attenuated after adjusting anti-hypertension medications in the models. Baseline SBP was associated with the change of processing speed/VMI function after adjusting vascular risk factors, WMHV, and cIMT at a 5-year follow-up. This longitudinal association was not found after adjusting anti-hypertension medications in the models. Further analyses revealed that individuals with category SBP from < 120 mmHg to≥140 mmHg had a linear decline in processing speed/VMI function at a 5-year follow-up.

CONCLUSION

We show that SBP is negatively associated with cognition cross-sectionally and longitudinally in the elderly. Anti-hypertension treatment eliminates the negative association of SBP with processing speed/VMI function longitudinally. Our findings support the treatment of stage 1 systolic hypertension in the elderly.

Pre-Statistical Considerations for Harmonization of Cognitive Instruments: Harmonization of ARIC, CARDIA, CHS, FHS, MESA, and NOMAS

BACKGROUND

Meta-analyses of individuals' cognitive data are increasing to investigate the biomedical, lifestyle, and sociocultural factors that influence cognitive decline and dementia risk. Pre-statistical harmonization of cognitive instruments is a critical methodological step for accurate cognitive data harmonization, yet specific approaches for this process are unclear.

OBJECTIVE

To describe pre-statistical harmonization of cognitive instruments for an individual-level meta-analysis in the blood pressure and cognition (BP COG) study.

METHODS

We identified cognitive instruments from six cohorts (the Atherosclerosis Risk in Communities Study, Cardiovascular Health Study, Coronary Artery Risk Development in Young Adults study, Framingham Offspring Study, Multi-Ethnic Study of Atherosclerosis, and Northern Manhattan Study) and conducted an extensive review of each item's administration and scoring procedures, and score distributions.

RESULTS

We included 153 cognitive instrument items from 34 instruments across the six cohorts. Of these items, 42%were common across ≥2 cohorts. 86%of common items showed differences across cohorts. We found administration, scoring, and coding differences for seemingly equivalent items. These differences corresponded to variability across cohorts in score distributions and ranges. We performed data augmentation to adjust for differences.

CONCLUSION

Cross-cohort administration, scoring, and procedural differences for cognitive instruments are frequent and need to be assessed to address potential impact on meta-analyses and cognitive data interpretation. Detecting and accounting for these differences is critical for accurate attributions of cognitive health across cohort studies.

Approaches to Studying Determinants of Racial-Ethnic Disparities in Stroke and Its Sequelae

Disparities are differences in health outcomes among groups that originate from sources including historically experienced social injustice and broadly defined environmental exposures. Large health disparities exist, defined by many factors including race/ethnicity, sex, age, geography, and socioeconomic status. Studying disparities relies on measures of disease burden. Traditional measures, such as mortality, may be less applicable to neurological disorders, which often lead to substantial morbidity and lower quality of life, without necessarily causing death. Measures such as disability-adjusted life-years or healthy life expectancy may be more appropriate for assessing neurological disease and permit comparisons across diseases and communities. There are many approaches that can be used to study disparities. Analyses of population-based observational studies, patient registries, and administrative data all contribute to the understanding of disparities in humans. Animal and other experimental designs, including clinical trials, may be used to identify mechanisms and strategies to reduce disparities. All of these approaches have strengths and weaknesses. Ultimately, understanding and mitigating disparities will require use of all of these methods. Crucially, a focus on not only improving outcomes among all individuals in society but minimizing or eliminating differences between those with better outcomes and those who have historically been disadvantaged should drive the ongoing investigations into disparities. This review is focused on epidemiological approaches to examining the depth and determinants of racial-ethnic disparities in the United States related to stroke, stroke care, and stroke outcomes.

Interventions Targeting Racial/Ethnic Disparities in Stroke Prevention and Treatment

Systemic racism is a public health crisis. Systemic racism and racial/ethnic injustice produce racial/ethnic disparities in health care and health. Substantial racial/ethnic disparities in stroke care and health exist and result predominantly from unequal treatment. This special report aims to summarize selected interventions to reduce racial/ethnic disparities in stroke prevention and treatment. It reviews the social determinants of health and the determinants of racial/ethnic disparities in care. It provides a focused summary of selected interventions aimed at reducing stroke risk factors, increasing awareness of stroke symptoms, and improving access to care for stroke because these interventions hold the promise of reducing racial/ethnic disparities in stroke death rates. It also discusses knowledge gaps and future directions.

Ideal vascular health and cognitive performance in the Brazilian Longitudinal Study of Adult Health

BACKGROUND AND PURPOSE

Most evidence for the association between ideal vascular health (IVH) and cognitive performance comes from high income countries. The aim was to investigate this association in the Brazilian Longitudinal Study of Adult Health.

METHODS

Cognition was assessed using the word list, verbal fluency and trail making tests. The IVH score included ideal metrics for body mass index, smoking, physical activity, diet, blood pressure, fasting glucose and total cholesterol. Poor, intermediate and optimal health were characterized in those presenting 0-2, 3-4, 5-7 ideal metrics, respectively. To determine the association between IVH score and cognitive performance, linear regression models adjusted for age, sex, education, race, alcohol use, depression and thyroid function were used.

RESULTS

In 12 271 participants, the mean age was 51.3 ± 8.9 years, 54% were women, 57% White and 53% had poor vascular health. Participants with intermediate (β = 0.064, 95% confidence interval 0.033; 0.096) and optimal health (β = 0.108, 95% confidence interval 0.052; 0.164) had better global cognitive Z-scores. In addition, interactions of IVH score with age, education and race were found, suggesting a better cognitive performance with higher IVH in older adults, Black/Brown participants and those with lower levels of education.

CONCLUSION

Ideal vascular health was associated with better cognitive performance. Older, Black/Brown and low-educated participants had better cognition in the presence of higher IVH scores.

Hypertension (Blood Pressure) and Lifetime Risk of Target Organ Damage

PURPOSE OF REVIEW

The purpose of this review is to describe the long-term or lifetime relationship between blood pressure and target organ damage. The use of the term "blood pressure" as opposed to hypertension is purposeful. The risk of cardiovascular disease from blood pressure begins below the levels of blood pressure defined as hypertension by contemporary definitions.

RECENT FINDINGS

An important recent publication that bears on this topic was the 2017 ACC/AHA Blood Pressure Management Guidelines. The redefinition of hypertension and blood pressure treatment goal to 130/80 mmHg and the decision to rely almost exclusively on data from event-based randomized controlled clinical trials, which led to a recommendation for lifestyle therapy only for most with stage 1 hypertension, were important. A report from the CARDIA study demonstrated significant risk for cardiovascular disease at 20 years for stage 1 hypertension. Based on all evidence, clinicians should consider the use of medication for stage 1 hypertension in those uncontrolled on lifestyle therapy.

Hypertension and Cognitive Health Among Older Adults in India

OBJECTIVES

To assess the prevalence of diagnosed and undiagnosed hypertension and their relationship to cognitive function in older adults in India.

DESIGN

Longitudinal Aging Study in India-Diagnostic Assessment of Dementia (LASI-DAD), an in-depth national study of late-life cognition and dementia.

SETTING

Geriatric hospitals and respondents' homes across 14 states in India.

PARTICIPANTS

N = 2,874 individuals aged 60 years and older from LASI-DAD.

MEASUREMENTS

Hypertension was identified by self-report of physician diagnosis or measured blood pressure (BP) of 140/90 mmHg or higher. Undiagnosed hypertension was defined as hypertensive BP measurements, but no physician diagnosis. Controlled hypertension was defined as BP lower than 140/90 mmHg among those with a physician diagnosis. Total hypertension included both diagnosed and undiagnosed hypertension. A summary cognition score, derived from the sum of 18 cognitive tests administered in the LASI-DAD (range = 0-360) was used to assess cognitive function.

RESULTS

Total hypertension prevalence was 63.2% (41.5% diagnosed and 21.6% undiagnosed). Among those with hypertension, 34.5% were undiagnosed, 34.2% were diagnosed but uncontrolled, and 31.3% were diagnosed and controlled. Neither diagnosed nor undiagnosed hypertension was related to cognitive function in fully adjusted models. Older age, female sex, less education, being widowed, rural residence, residing in the north or central regions, being in a scheduled caste or tribe, low consumption, being underweight, and history of stroke were all independently associated with worse cognitive test performance.

CONCLUSION

Two-thirds of older Indian adults had hypertension, with the majority being undiagnosed or diagnosed but not adequately controlled. Hypertension was not independently associated with cognitive function, whereas sociodemographic factors were independently related to cognitive function. J Am Geriatr Soc 68:S29-S35, 2020.