Relationships among blood pressure, triglycerides and verbal learning in African Americans

Enabling Lipidomic Biomarker Studies for Protected Populations by Combining Noninvasive Fingerprint Sampling with MS Analysis and Machine Learning

Triacylglycerols and wax esters are two lipid classes that have been linked to diseases, including autism, Alzheimer's disease, dementia, cardiovascular disease, dry eye disease, and diabetes, and thus are molecules worthy of biomarker exploration studies. Since triacylglycerols and wax esters make up the majority of skin-surface lipid secretions, a viable sampling method for these potential biomarkers would be that of groomed latent fingerprints. Currently, however, blood-based sampling protocols predominate in the field. The invasiveness of a blood draw limits its utility to protected populations, including children and the elderly. Herein we describe a noninvasive means for sample collection (from fingerprints) paired with fast MS data-acquisition (MassIVE data set MSV000092742) and efficient data analysis via machine learning. Using both supervised and unsupervised classification, we demonstrate the usefulness of this method in determining whether a variable of interest imparts measurable change within the lipidomic data set. As a proof-of-concept, we show that the method is capable of distinguishing between the fingerprints of different individuals as well as between anatomical sebum collection regions. This noninvasive, high-throughput approach enables future lipidomic biomarker researchers to more easily include underrepresented, protected populations, such as children and the elderly, thus moving the field closer to definitive disease diagnoses that apply to all.

Association Between Triglycerides and Risk of Dementia in Community-Dwelling Older Adults: A Prospective Cohort Study

BACKGROUND AND OBJECTIVES

It has been suggested that higher triglyceride levels were associated with a lower risk of Alzheimer disease. This study aimed to examine the association of triglycerides with dementia and cognition change in community-dwelling older adults.

METHODS

This prospective longitudinal study used data from the Aspirin in Reducing Events in the Elderly (ASPREE) randomized trial of adults aged 65 years or older without dementia or previous cardiovascular events at enrollment. The main outcome was incident dementia. Other outcomes included changes in composite cognition and domain-specific cognition (global cognition, memory, language and executive function, and psychomotor speed). The association between baseline triglycerides and dementia risk was estimated using Cox proportional hazard models adjusting for relevant risk factors. Linear mixed models were used to investigate cognitive change. The analysis was repeated in a subcohort of participants with available APOE-ε4 genetic data with additional adjustment for APOE-ε4 carrier status and an external cohort (UK Biobank) with similar selection criteria applied.

RESULTS

This study included 18,294 ASPREE participants and 68,200 UK Biobank participants (mean age: 75.1 and 66.9 years; female: 56.3% and 52.7%; median [interquartile range] triglyceride: 106 [80-142] mg/dL and 139 [101-193] mg/dL), with dementia recorded in 823 and 2,778 individuals over a median follow-up of 6.4 and 12.5 years, respectively. Higher triglyceride levels were associated with lower dementia risk in the entire ASPREE cohort (hazard ratio [HR] with doubling of triglyceride: 0.82, 95% CI 0.72-0.94). Findings were similar in the subcohort of participants with APOE-ε4 genetic data (n = 13,976) and in the UK Biobank cohort (HR was 0.82 and 0.83, respectively, all p ≤ 0.01). Higher triglycerides were also associated with slower decline in composite cognition and memory over time (p ≤ 0.05).

DISCUSSION

Older adults with higher triglyceride levels within the normal to high-normal range had a lower dementia risk and slower cognitive decline over time compared with individuals with lower triglyceride levels. Higher triglyceride levels may be reflective of better overall health and/or lifestyle behaviors that would protect against dementia development. Future studies are warranted to investigate whether specific components within the total circulating pool of plasma triglycerides may promote better cognitive function, with the hope of informing the development of new preventive strategies.

Plasma apolipoprotein E levels, isoform composition, and dimer profile in relation to plasma lipids in racially diverse patients with Alzheimer's disease and mild cognitive impairment

BACKGROUND

The APOEε4-promoted risk of Alzheimer's disease (AD) is lower in Black/African-Americans (B/AAs), compared to non-Hispanic whites (NHWs). Previous studies reported lower plasma apolipoprotein E (apoE) levels in NHW APOEε4-carriers compared to non-carriers, and low plasma apoE levels were directly associated with an increased risk of AD and all dementia. We further showed that APOEε3/ε3 AD patients exhibited reduced plasma apoE dimers compared to corresponding control subjects. Whether plasma apoE levels and apoE dimer formation differ between races/ethnicities and therefore may help explain AD risk racial disparity remains to be elucidated.

METHODS

Using mass spectrometry, we determined total plasma apoE and apoE isoform levels in a cohort of B/AAs (n = 58) and NHWs (n = 67) including subjects with normal cognition (B/AA: n = 25, NHW: n = 28), mild cognitive impairment (MCI) (B/AA: n = 24, NHW: n = 24), or AD dementia (B/AA: n = 9, NHW: n = 15). Additionally, we used non-reducing western blot analysis to assess the distribution of plasma apoE into monomers/disulfide-linked dimers. Plasma total apoE, apoE isoform levels, and % apoE monomers/dimers were assessed for correlations with cognition, cerebrospinal fluid (CSF) AD biomarkers, sTREM2, neurofilament light protein (NfL), and plasma lipids.

RESULTS

Plasma apoE was predominantly monomeric in both racial groups and the monomer/dimer distribution was not affected by disease status, or correlated with CSF AD biomarkers, but associated with plasma lipids. Plasma total apoE levels were not related to disease status and only in the NHW subjects we observed lower plasma apoE levels in the APOEε4/ε4-carriers. Total plasma apoE levels were 13% higher in B/AA compared to NHW APOEε4/ε4 subjects and associated with plasma high-density lipoprotein (HDL) in NHW subjects but with low-density lipoprotein levels (LDL) in the B/AA subjects. Higher plasma apoE4 levels, exclusively in APOEε3/ε4 B/AA subjects, were linked to higher plasma total cholesterol and LDL levels. In the controls, NHWs and B/AAs exhibited opposite associations between plasma apoE and CSF t-tau.

CONCLUSIONS

The previously reported lower APOEε4-promoted risk of AD in B/AA subjects may be associated with differences in plasma apoE levels and lipoprotein association. Whether differences in plasma apoE levels between races/ethnicities result from altered APOEε4 expression or turnover, needs further elucidation.

Gender-specific association of blood lipids and reproductive trajectory with cognitive impairment: A community based cross-sectional study from India

Background

Abnormal blood lipid levels in the general population and adverse reproductive events among women have been associated with cognitive impairment (CI). However, their relationship has not been extensively studied in community settings. Hence, this study aims to explore the association of CI with blood lipid levels in both sexes and reproductive events/trajectory among women.

Methods

A cross-sectional study was conducted among a North Indian rural population. A total of 808 adults were recruited through door-to-door household survey. Data on socio-demographic variables, reproductive profile of women, and cognitive impairment status were collected. Fasting blood sample was collected to estimate serum lipid profile. Multivariate logistic regression was performed to test for association.

Results

The study demonstrated a lack of association between lipid profile and cognitive impairment among males. Surprisingly, low HDL-C among females was found to be protective against moderate/severe cognitive impairment (value of p = 0.049). Further, menopausal women and those having five or higher live births were found to be at higher risk of CI than pre-menopausal women and those with 1-2 live births, respectively.

Conclusion

The present study hints toward a gender-specific association of blood lipid levels with CI. Further, higher live births and menopause appear to be important risk factors for CI among women.

Components of metabolic syndrome associated with lower neurocognitive performance in youth with perinatally acquired HIV and youth who are HIV-exposed uninfected

We investigated the association of metabolic syndrome (MetS) and its components [abdominal obesity, elevated triglycerides (TG), low HDL cholesterol, elevated blood pressure (BP), and impaired fasting glycemia (IFG)] with neurocognitive impairment in youth with perinatally acquired HIV (YPHIV) or who are perinatally HIV-exposed uninfected (YPHEU). This was an observational study with a comparison group of 350 YPHIV and 68 YPHEU ages 10-19 years. Youth with MetS components measured between 1 year before and 3 months after a baseline neurocognitive assessment (Wechsler Intelligence Scale) were selected from the Pediatric HIV/AIDS Cohort Study (PHACS). A sub-group completed another assessment 3 years later. We assessed the association of each baseline MetS component with five standardized neurocognitive indices at baseline and changes in indices over time. At baseline, 15% of YPHIV and 18% of YPHEU met criteria for ≥ 2 MetS components. Among YPHIV, there was no association between MetS components and neurocognitive indices at baseline; however, over time, elevated baseline BP was associated with a greater decrease in mean Perceptual Reasoning scores (-4.3;95%CI: -8.8,0.3) and ≥ 2 MetS components with a greater decrease in mean Processing Speed scores (-5.1;95%CI: -9.4, -0.8). Among YPHEU, elevated TG was associated with lower mean Verbal Comprehension, Perceptual Reasoning, and Full-scale IQ scores at baseline, and IFG with lower mean Verbal Comprehension scores. Components of MetS in YPHIV (elevated BP) and YPHEU (elevated TG and IFG) were associated with lower neurocognitive performance index scores. Studies to elucidate how modifying metabolic risk factors early in life may improve neurocognitive outcomes in this population are warranted.

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).

The Role of High Triglycerides Level in Predicting Cognitive Impairment: A Review of Current Evidence

The burden of cognitive disorders is huge and still growing, however the etiology and the degree of cognitive impairment vary considerably. Neurodegenerative and vascular mechanisms were most frequently assessed in patients with dementia. Recent studies have shown the possible involvement of triglycerides levels in cognitive function through putative mechanisms such as brain blood barrier dysfunction or amyloid metabolism imbalance, but not all research in the field found this association. Several clinical studies evaluated the relationship between different forms of cognitive decline and levels of serum triglycerides, independent of other cardiovascular risk factors. This review focuses on the role of triglycerides in cognitive decline, cerebral amyloidosis and vascular impairment. Considering that the management of hypertriglyceridemia benefits from lifestyle modification, diet, and specific drug therapy, future studies are requested to appraise the triglycerides-cognitive impairment relationship.

D-ribose and pathogenesis of Alzheimer's disease

It is estimated that the global prevalence of dementia will rise as high as 24 million and predicted to be double in every 20 years which is attributed to the fact that the ageing population is increasing and so more individuals are at risk of developing neurodegenerative diseases like Alzheimer's. Many scientists favored glycation of proteins such as tau, amyloid beta (Aβ) etc. as one of the important risk factor in Alzheimer's disease (AD). Since, D-ribose shows highest glycation ability among other sugars hence, produces advanced glycation end products (AGEs) rapidly. However, there are several other mechanisms suggested by researchers through which D-ribose may cause cognitive impairments. There is a concern related to diabetic patients since they also suffer from D-ribose metabolism, may be more prone to AD risk. Thus, it is imperative that the pathogenesis and the pathways involved in AD progression are explored in the light of ribosylation and AGEs formation for identifying suitable diagnostics marker for early diagnosis or finding promising therapeutic outcomes.

CE: Original Research: Midlife Hypertension and Hypercholesterolemia in Relation to Cognitive Function Later in Life in Black Women

: Purpose: This study sought to evaluate midlife hypertension and hypercholesterolemia in relation to cognitive function later in life among black women.

METHODS

Participants were drawn from the Nurses' Health Study and the Women's Health Study databases. In these studies, health professionals reported health information by questionnaire at baseline and at regular follow-up intervals, including diagnoses of hypertension, hypercholesterolemia, or both; and they completed telephone-based cognitive assessments later in life. Multivariable-adjusted linear regression models were used to estimate mean differences in global cognition and executive function scores, comparing women with and without a history of hypertension at midlife and women with and without a history of hypercholesterolemia at midlife.

RESULTS

Data for 363 black female health professionals were analyzed. Those with a history of hypertension or hypercholesterolemia at midlife did not have lower global cognition and executive function scores later in life compared with those without such a history, although there were trends in this direction.

CONCLUSION

In the study sample, a history of hypertension or hypercholesterolemia at midlife was not related to worse cognitive function in later life. But there was a suggestive pattern of trends that warrants further exploration in larger studies.

Relationship between plasma lipids and mild cognitive impairment in the elderly Chinese: a case-control study

Background

High lipid levels may constitute a more important risk factor for cognitive health in previous studies. However, the association of plasma lipids with mild cognitive impairment (MCI) among elderly people had not been studied exactly. This study aims to explore the relationship between plasma lipids/lipoproteins and the risk of MCI in elderly Chinese individuals.

Methods

CSI-MCI study was a preliminary case-control study of the association of plasma lipids/lipoproteins with MCI in 112 MCI cases and 115 cognitively normal controls. Plasma total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and triglycerides (TG) levels were measured in fasting blood samples. Multivariable logistic regression was used to evaluate the potential association between MCI and these factors. Statistical models were adjusted for multiple demographic and biological covariates.

Results

The subjects with MCI were significantly older, higher percentage of females and less educated than controls (P <0.05). As expected, subjects with MCI had lower MMSE score compared with controls (P <0.05). Multivariate logistic regression analysis showed that higher plasma TC level was associated with the risk of MCI in models adjusting for age, sex and education. However, This association was attenuated after adjusting for BMI, Type 2 diabetes mellitus, heart disease and hypertension. Plasma TG level was negatively associated with the risk of MCI. The adjusted odds ratio (OR) of MCI was significantly reduced for the highest quartile of plasma TG level (OR: 0.76, 95 % CI: 0.48–0.97), but not for the second or third quartile, compared with the lowest quartile (adjusted models). Plasma HDL level was significantly negatively associated with the risk of MCI. There was no association between plasma LDL level and the risk of MCI, adjustment for demographics, vascular disorders did not change this relation.

Conclusions

Plasma TC was significantly higher in MCI subjects compared to cognitively normal controls, Elevated plasma HDL and triglyceride were associated with the occurrence of MCI. These findings need to be confirmed in further longitudinal studies.

Older adult awareness of the influence of cardiovascular disease risk factors on cognitive function

AIMS AND OBJECTIVES

The aims of the current study were to (i) assess older people's awareness of the association between CVD risk factors and cognitive function; and (ii) examine whether awareness varies as a function of demographic factors.

BACKGROUND

Cardiovascular disease (CVD) risk factors have been linked to subtle deficits in cognitive function. CVD risk factors increase the risk of cognitive decline and dementia. The association between cardiovascular disease (CVD) risk factors and cognitive decrements has been well documented among older people; however, we are unaware of any studies that have measured older people's awareness of this relationship in an effort to assess educational needs.

DESIGN

A descriptive, cross-sectional survey design was employed.

METHODS

Community-based older adults aged 60 and older completed a survey that assessed their knowledge of the association between CVD risk factors and cognitive function.

RESULTS

One hundred fifty older adults, with a mean age of 72.88 years, completed the survey. Results showed that over 75% of the sample was aware that CVD risk factors affect cognitive function. White older adults and older adults with greater perceived financial well-being tended to be more aware of these relationships than non-White participants with less perceived financial well-being.

CONCLUSIONS

Results suggest that many, but not all older people have awareness of this relationship. As such, there is a need for increased education about the cognitive effects of CVD risk factors, particularly among older people who are already at risk for developing CVD and those with lesser financial well-being.

IMPLICATIONS FOR PRACTICE

Appropriate educational strategies can expose older patients to the importance of healthy lifestyle and self-care to maintain cognitive function. Nurses can incorporate education into care by identifying patients that would benefit from tailored interventions and providing information to at-risk patients about how to maintain their cognitive function through management of specific CVD risk factors.

Diet quality and cognitive function in an urban sample: findings from the Healthy Aging in Neighborhoods of Diversity across the Life Span (HANDLS) study

OBJECTIVE

Poor diet quality contributes to morbidity, including poor brain health outcomes such as cognitive decline and dementia. African Americans and individuals living in poverty may be at greater risk for cognitive decrements from poor diet quality.

DESIGN

Cross-sectional.

SETTING

Baltimore, MD, USA.

SUBJECTS

Participants were 2090 African Americans and Whites (57 % female, mean age=47·9 years) who completed two 24 h dietary recalls. We examined cognitive performance and potential interactions of diet quality with race and poverty status using baseline data from the Healthy Aging in Neighborhoods of Diversity across the Life Span (HANDLS) study. Healthy Eating Index-2010 (HEI-2010) scores were calculated and interpreted using federal guidelines. A neurocognitive test battery was administered to evaluate cognitive function over several domains.

RESULTS

Linear regression analyses showed that lower HEI-2010 scores were associated with poorer verbal learning and memory (P<0·05) after adjustment for covariates. Diet quality within the sample was poor. Significant interactions of HEI-2010 and poverty status (all P<0·05) indicated that higher diet quality was associated with higher performance on tests of attention and cognitive flexibility, visuospatial ability and perceptual speed among those below the poverty line. No significant race interactions emerged. Higher diet quality was associated with better performance on two measures of verbal learning and memory, irrespective of race and poverty status.

CONCLUSIONS

Findings suggest that diet quality and cognitive function are likely related at the population level. Future research is needed to determine whether the association is clinically significant.

Cognition and health in African American men

OBJECTIVE

Despite high rates of poor health outcomes, little attention has been focused on associations between prominent health factors and cognitive function in African American men, exclusively. The objective was to examine relationships between cardiovascular and pulmonary health, and cognitive function in African American men.

METHOD

Data from 257 men were pooled from two studies of African American aging. The mean age of participants was 58.15 and mean educational attainment was 11.78 years. Participants provided self-reported health and demographic information, completed cognitive measures, and had their blood pressure and peak expiratory flow assessed.

RESULTS

After adjustment, significant relationships were found between average peak expiratory flow rate (APEFR) and cognitive performance measures.

DISCUSSION

Results suggest that lung function is important to consider when examining cognitive function in African American men. Understanding the role of health in cognition and implications for quality of life in this population will be critical as life expectancies increase.

Task demand influences relationships among sex, clustering strategy, and recall: 16-word versus 9-word list learning tests

OBJECTIVE

We compared the relationships among sex, clustering strategy, and recall across different task demands using the 16-word California Verbal Learning Test-Second Edition (CVLT-II) and the 9-word Philadelphia (repeatable) Verbal Learning Test (PrVLT).

BACKGROUND

Women generally score higher than men on verbal memory tasks, possibly because women tend to use semantic clustering. This sex difference has been established via word-list learning tests such as the CVLT-II.

METHODS

In a retrospective between-group study, we compared how 2 separate groups of cognitively healthy older adults performed on a longer and a shorter verbal learning test. The group completing the CVLT-II had 36 women and 26 men; the group completing the PrVLT had 27 women and 21 men.

RESULTS

Overall, multiple regression analyses revealed that semantic clustering was significantly associated with total recall on both tests' lists (P<0.001). Sex differences in recall and semantic clustering diminished with the shorter PrVLT word list.

CONCLUSIONS

Semantic clustering uniquely influenced recall on both the longer and shorter word lists. However, serial clustering and sex influenced recall depending on the length of the word list (ie, the task demand). These findings suggest a complex nonlinear relationship among verbal memory, clustering strategies, and task demand.

High normal plasma triglycerides are associated with preserved cognitive function in Chinese oldest-old

OBJECTIVE

to explore the relationship between blood lipids/lipoproteins and cognitive function in the Chinese oldest-old.

DESIGN

multivariate statistical analysis using cross-sectional data.

SETTING

community-based setting in longevity areas in China.

SUBJECTS

eight hundred and thirty-six subjects aged 80 and older were included in the sample.

METHODS

plasma total cholesterol, triglycerides, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, blood pressure and fasting plasma glucose were measured and information about demographics and lifestyle was collected. Cognitive status was assessed using the Mini-Mental State Examination (MMSE).

RESULTS

cumulative logit model analysis showed that triglyceride was significantly negatively associated with cognitive impairment. By general linear modelling, there was a significant linear trend of MMSE scores with the level of triglyceride, but not with levels of cholesterol after adjustment. The odds ratio (OR) of cognitive impairment (MMSE score < 18) was significantly reduced for the highest quartile of plasma triglyceride concentration (OR: 0.52, 95% CI: 0.33-0.84), but not for the second or third quartile, compared with the lowest quartile (adjusted models). There were no significant associations between cognitive impairment and cholesterol.

CONCLUSION

we concluded that high normal plasma triglyceride was associated with preservation of cognitive function while lower concentrations were not in the Chinese oldest-old.

Role of the blood-brain barrier in the evolution of feeding and cognition

The blood-brain barrier (BBB) regulates the blood-to-brain passage of gastrointestinal hormones, thus informing the brain about feeding and nutritional status. Disruption of this communication results in dysregulation of feeding and body weight control. Leptin, which crosses the BBB to inform the CNS about adiposity, provides an example. Impaired leptin transport, especially coupled with central resistance, results in obesity. Various substances/conditions regulate leptin BBB transport. For example, triglycerides inhibit leptin transport. This may represent an evolutionary adaptation in that hypertriglyceridemia occurs during starvation. Inhibition of leptin, an anorectic, during starvation could have survival advantages. The large number of other substances that influence feeding is explained by the complexity of feeding. This complexity includes cognitive aspects; animals in the wild are faced with cost/benefit analyses to feed in the safest, most economical way. This cognitive aspect partially explains why so many feeding substances affect neurogenesis, neuroprotection, and cognition. The relation between triglycerides and cognition may be partially mediated through triglyceride's ability to regulate the BBB transport of cognitively active gastrointestinal hormones such as leptin, insulin, and ghrelin.