Hypertension and Cognitive Impairment: A Review of Mechanisms and Key Concepts

DNA Methylation Mediates the Association Between Cardiometabolic Risk Factors and Cognition: Findings From the Health and Retirement Study

The association between cardiometabolic risk factors and cognitive function has been well documented, but the underlying mechanisms are not fully understood. This longitudinal study aimed to investigate the potential mediating role of DNA methylation in this association. We conducted the analyses in 3 708 participants (mean [standard deviation {SD}] age: 67.3 [9.5], women: 57.9%) from the Health and Retirement Study who were assessed in the 2014-2020 waves, had Infinium Methylation EPIC BeadChip methylation assays from the 2016 Venous Blood Study, and had cognitive assessment between 2016 and 2020. Causal mediation analyses were used to test the mediation role of DNA methylation in the associations between cardiometabolic risk factors and cognition, adjusting for demographic, socioeconomic, and lifestyle factors. Hypertension (-0.061 in composite cognitive z-score; 95% confidence interval [CI: -0.119, -0.004]) and diabetes (-0.134; 95% CI: [-0.198, -0.071]) were significantly associated with worse cognitive function while abnormal body weight and hypercholesterolemia were not. An increased number of cardiometabolic risk factors was associated with worse cognitive function (p = .002). DNA methylation significantly mediated the association of hypertension (mediated effect on composite cognitive z-score: -0.023; 95% CI: -0.033, -0.014), diabetes (-0.022; 95% CI: -0.032, -0.014), and obesity (-0.021; 95% CI: -0.033, -0.011) with cognitive function, whereas the mediation effect was not observed for having hypercholesterolemia. The estimated proportions mediated were 37.4% for hypertension and 16.7% for diabetes. DNA methylation may be an important mediator linking cardiometabolic risk factors to worse cognition and might even provide a potential target for dementia prevention.

Essential New Complexity-Based Themes for Patient-Centered Diagnosis and Treatment of Dementia and Predementia in Older People: Multimorbidity and Multilevel Phenomenology

Dementia is a highly prevalent condition with devastating clinical and socioeconomic sequela. It is expected to triple in prevalence by 2050. No treatment is currently known to be effective. Symptomatic late-onset dementia and predementia (SLODP) affects 95% of patients with the syndrome. In contrast to trials of pharmacological prevention, no treatment is suggested to remediate or cure these symptomatic patients. SLODP but not young onset dementia is intensely associated with multimorbidity (MUM), including brain-perturbating conditions (BPCs). Recent studies showed that MUM/BPCs have a major role in the pathogenesis of SLODP. Fortunately, most MUM/BPCs are medically treatable, and thus, their treatment may modify and improve SLODP, relieving suffering and reducing its clinical and socioeconomic threats. Regrettably, the complex system features of SLODP impede the diagnosis and treatment of the potentially remediable conditions (PRCs) associated with them, mainly due to failure of pattern recognition and a flawed diagnostic workup. We suggest incorporating two SLODP-specific conceptual themes into the diagnostic workup: MUM/BPC and multilevel phenomenological themes. By doing so, we were able to improve the diagnostic accuracy of SLODP components and optimize detecting and favorably treating PRCs. These revolutionary concepts and their implications for remediability and other parameters are discussed in the paper.

Epimedium flavonoids improve cerebral white matter lesions by inhibiting neuroinflammation and activating neurotrophic factor signal pathways in spontaneously hypertensive rats

Cerebral small vessel disease (CSVD) is one of the most common nervous system diseases. Hypertension and neuroinflammation are considered important risk factors for the development of CSVD and white matter (WM) lesions. We used the spontaneously hypertensive rat (SHR) as a model of early-onset CSVD and administered epimedium flavonoids (EF) for three months. The learning and memorization abilities were tested by new object recognition test. The pathological changes of WM were assessed using magnetic resonance imaging, transmission electron microscopy (TEM), Luxol fast blue and Black Gold staining. Oligodendrocytes (OLs) and myelin basic protein were detected by immunohistochemistry. The ultrastructure of the tight junctions was examined using TEM. Microglia and astrocytes were detected by immunofluorescence. RNA-seq was performed on the corpus callosum of rats. The results revealed that EF could significantly improve the learning and memory impairments in SHR, alleviate the injury and demyelination of WM nerve fibers, promote the differentiation of oligodendrocyte precursor cells (OPCs) into mature OLs, inhibit the activation of microglia and astrocytes, inhibit the expression of p38 MAPK/NF-κB p65/NLRP3 and inflammatory cytokines, and increase the expression of tight-junction related proteins ZO-1, occludin, and claudin-5. RNA-seq analysis showed that the neurotrophin signaling pathway played an important role in the disease. RT-qPCR and WB results showed that EF could regulate the expression of nerve growth factor and brain-derived neurotrophic factor and their downstream related proteins in the neurotrophin signaling pathway, which might explain the potential mechanism of EF's effects on the cognitive impairment and WM damage caused by hypertension.

Comparable cerebral cortex activity and gait performance in elderly hypertensive and healthy individuals during dual-task walking: A fNIRS study

BACKGROUND

Hypertension increases the risk of cognitive impairment and related dementia, causing impaired executive function and unusual gait parameters. However, the mechanism of neural function illustrating this is unclear. Our research aimed to explore the differences of cerebral cortex activation, gait parameters, and working memory performance between healthy older adults (HA) and older hypertensive (HT) patients when performing cognitive and walking tasks.

METHOD

A total of 36 subjects, including 12 healthy older adults and 24 older hypertensive patients were asked to perform series conditions including single cognitive task (SC), single walking task (SW), and dual-task (DT), wearing functional near-infrared spectroscopy (fNIRS) equipment and Intelligent Device for Energy Expenditure and Activity equipment to record cortical hemodynamic reactions and various gait parameters.

RESULTS

The left somatosensory cortex (L-S1) and bilateral supplementary motor area (SMA) showed higher cortical activation (p < .05) than HA when HT performed DT. The intragroup comparison showed that HT had higher cortical activation (p < .05) when performing DT as SW. The cognitive performance of HT was significantly worse (p < .05) than HA when executing SC. The activation of the L-S1, L-M1, and bilateral SMA in HT were significantly higher during SW (p < .05).

CONCLUSION

Hypertension can lead to cognitive impairment in the elderly, including executive function and walking function decline. As a result of these functional declines, elderly patients with hypertension are unable to efficiently allocate brain resources to support more difficult cognitive interference tasks and need to meet more complex task demands by activating more brain regions.

Cognitive impairment in cerebral small vessel disease induced by hypertension

ABSTRACT

Hypertension is a primary risk factor for the progression of cognitive impairment caused by cerebral small vessel disease, the most common cerebrovascular disease. However, the causal relationship between hypertension and cerebral small vessel disease remains unclear. Hypertension has substantial negative impacts on brain health and is recognized as a risk factor for cerebrovascular disease. Chronic hypertension and lifestyle factors are associated with risks for stroke and dementia, and cerebral small vessel disease can cause dementia and stroke. Hypertension is the main driver of cerebral small vessel disease, which changes the structure and function of cerebral vessels via various mechanisms and leads to lacunar infarction, leukoaraiosis, white matter lesions, and intracerebral hemorrhage, ultimately resulting in cognitive decline and demonstrating that the brain is the target organ of hypertension. This review updates our understanding of the pathogenesis of hypertension-induced cerebral small vessel disease and the resulting changes in brain structure and function and declines in cognitive ability. We also discuss drugs to treat cerebral small vessel disease and cognitive impairment.

Hypertension Impacts the Oscillatory Dynamics Serving the Encoding Phase of Verbal Working Memory

BACKGROUND

Chronic hypertension is known to be a major contributor to cognitive decline, with executive function and working memory being among the domains most commonly affected. Despite the growing literature on such dysfunction in patients with hypertension, the underlying neural processes are poorly understood.

METHODS

In this cross-sectional study, we examine these neural processes by having participants with controlled hypertension, uncontrolled hypertension, and healthy controls perform a verbal working memory task during magnetoencephalography. Neural oscillations associated with the encoding and maintenance components of the working memory task were imaged and statistically evaluated among the 3 groups.

RESULTS

Differences related to hypertension emerged during the encoding phase, where the hypertension groups exhibited weaker α-β oscillatory responses compared with controls in the left parietal cortices, whereas such oscillatory activity differed between the 2 hypertension groups in the right prefrontal regions. Importantly, these neural responses in the prefrontal and parietal cortices during encoding were also significantly associated with behavioral performance across all participants.

CONCLUSIONS

Overall, our data suggest that hypertension is associated with neurophysiological abnormalities during working memory encoding, whereas the neural processes serving maintenance seem to be preserved. The right hemispheric neural responses likely reflected compensatory processing, which patients with controlled hypertension may use to achieve verbal working memory function at the level of controls, as opposed to the uncontrolled hypertension group where diminished resources may have limited such additional recruitment.

The Impact of Hypertension on Cognitive Decline and Alzheimer's Disease and Its Management: A Systematic Review

Hypertension, a major risk factor for cardiovascular diseases, has also been linked to cognitive decline and Alzheimer's disease (AD). This systematic review synthesizes the current evidence on how managing hypertension may influence cognitive health, particularly among elderly populations and those with cognitive impairments. By analyzing data from randomized controlled trials (RCTs), clinical trials, and cross-sectional studies, we evaluated the efficacy of various interventions, including pharmacological treatments, lifestyle modifications, and multidomain approaches that address blood pressure (BP) variability and intensive versus standard blood pressure control. Our findings reveal that effective blood pressure management can mitigate cognitive decline and potentially alter the course of Alzheimer's disease. However, the results also highlight complexities, such as the risk of adverse effects from intensive blood pressure control on cognitive processing and hippocampal volume. This review underscores the need for tailored hypertension management strategies that balance cardiovascular health with cognitive outcomes, suggesting that stabilizing blood pressure variability could play a crucial role. Future research should focus on longitudinal studies to refine these management strategies and enhance treatment guidelines, improving overall outcomes for patients at risk of cognitive decline.

An assessment of the mediating role of hypertension in the effect of long-term air pollution exposure on dementia

Background

Growing evidence links air pollution exposure to the risk of dementia. We hypothesized that hypertension may partially mediate this effect.

Methods

We previously documented an association between air pollution and dementia in the Ginkgo Evaluation of Memory Study, a randomized, placebo-controlled trial of 3069 adults ≥75 years across four US sites who were evaluated for dementia every 6 months from 2000-2008. We utilized a two-stage regression approach for causal mediation analysis to decompose the total effect of air pollution on dementia into its natural direct and indirect effect through prevalent hypertension. Exposure to air pollution in the 10 or 20 years before enrollment was assigned using estimates from fine-scale spatial-temporal models for PM2.5, PM10, and NO2. We used Poisson regression models for hypertension and Cox proportional hazard models for time-to-incident all-cause dementia, adjusting for a priori confounders.

Results

Participants were free of mild cognitive impairment at baseline (n = 2564 included in analyses); 69% had prevalent hypertension at baseline. During follow-up, 12% developed all-cause dementia (Alzheimer's disease [AD] = 212; vascular dementia with or without AD [VaD/AD mixed] = 97). We did not find an adverse effect of any air pollutant on hypertension. Hypertension was associated with VaD/AD mixed (HR, 1.92 [95% CI = 1.14, 3.24]) but not AD. We did not observe mediation through hypertension for the effect of any pollutant on dementia outcomes.

Conclusions

The lack of mediated effect may be due to other mechanistic pathways and the minimal effect of air pollution on hypertension in this cohort of older adults.

Hypertension is associated with reduced resting-state medial temporal lobe dynamic network flexibility in older African Americans

Hypertension disproportionately affects African Americans and is a risk factor for Alzheimer's disease (AD). We investigated the relationship of blood pressure (BP) with medial temporal lobe (MTL) dynamic network flexibility (a novel AD biomarker) and cognitive generalization in older African Americans. In a cross-sectional study, 37 normotensive (systolic BP <130 mmHg, 82.5% F, 64.4 ± 4.9 years; 14.3 ± 2.1 years of education) versus 79 hypertensive (systolic BP ≥130 mmHg, 79.5% F, 66.8 ± 4.1 years; 14.0 ± 0.2 years of education) participants were enrolled. All participants completed a 10-min resting-state functional magnetic resonance imaging scan to assess MTL dynamic network flexibility and two generalization tasks to assess cognition. Anthropometrics and aerobic fitness (via 6-min walk test) were also determined. There was no difference in BMI (29.7 ± 6.4 vs. 31.9 ± 6.3 kg/m2, p = 0.083) or aerobic fitness (15.5 ± 2.6 vs. 15.1 ± 2.6 mL/kg/min; p = 0.445) between normotensive and hypertensive groups. However, normotensive participants had higher MTL dynamic network flexibility compared to hypertensive participants (0.42 ± 0.23 vs. 0.32 ± 0.25 mL, p = 0.040), and this was associated with higher mean arterial blood pressure (r = -0.21, p = 0.036). Therefore, hypertensive older African Americans demonstrated lower MTL dynamic network flexibility compared to their normotensive counterparts independent of BMI and aerobic fitness. Further studies are required to determine how blood pressure mediates AD risk in African Americans.

Hypertension and Mild Cognitive Impairment: State-of-the-Art Review

BACKGROUND

Mid-life hypertension is associated with cognitive decline and dementia in later life. Reducing high blood pressure (BP) with antihypertensive agents is a well-researched strategy to prevent dementia and mild cognitive impairment (MCI). However, there is still limited direct evidence to support the approach, and particularly for the treatment of the very old and those with existing MCI.

METHODS

This review presents an overview of the current evidence for the relationship between MCI and hypertension, and of the potential pathophysiological mechanisms related to cognitive decline and incidence dementia in relation to aging.

RESULTS

Although observational data are near consistent in showing an association between mid-life hypertension and MCI and/or dementia, the evidence in relation to hypertension in younger adults and the very old (age >80 years) is much more limited. Most of the commonly available antihypertensive agents appear to provide beneficial effects in reducing the risk dementia, but there is limited evidence to support such treatment in those with existing MCI.

CONCLUSIONS

Further studies are needed to determine the optimal levels of BP control across different age groups, especially in adults with MCI, and which class(es) of antihypertensive agents and duration of treatment best preserve cognitive function in those at risk of, or with established, MCI.

2-(4-Methylthiazol-5-yl) Ethyl Nitrate Hydrochloride Ameliorates Cognitive Impairment via Modulation of Oxidative Stress and Nuclear Factor Kappa B (NF-κB) Signaling Pathway in Chronic Cerebral Hypoperfusion-Associated Spontaneously Hypertensive Rats

Hypertension reduces the bioavailability of vascular nitric oxide (NO) and contributes to the onset of vascular dementia (VaD). A loss of NO bioavailability increases inflammation and oxidative stress. 2-(4-Methylthiazol-5-yl) ethyl nitrate hydrochloride (W1302) is a novel nitric oxide donor (NOD) which is undergoing phase I clinical trials in China for the treatment of VaD. In this study, we investigated the protective effects of W1302 in VaD rats induced by the permanent occlusion of a bilateral common carotid arteries model related to spontaneous hypertension (SHR-2VO), and we further explored the underlying mechanisms. Nimodipine was used as a positive control. Our results showed that W1302 treatment for 4 weeks (10 mg/Kg/day) exhibited stronger improvement in the spatial learning and memory deficits in SHR-2VO rats compared with nimodipine with slightly lower systolic blood pressure (SBP). Meanwhile, W1302 treatment significantly increased NO and cGMP production, restored mitochondrial membrane potential and attenuated oxidative stress as evidenced by increasing ATP production and reducing malondialdehyde (MDA) levels in the brain. Furthermore, W1302 treatment markedly inhibited the iNOS activity and decreased TNF-α expression via inhibiting the nuclear factor kappa B (NF-κB) signaling pathway. Nimodipine treatment also restored these aberrant changes, but its ATP production was weaker than that of W1302, and there was no significant effect on NO release. Taken together, W1302 exhibited beneficial effects on complications in VaD with hypertension, which is involved in suppressing oxidative damage, and the inflammatory reaction might be mediated by an increase in NO release. Therefore, W1302 has therapeutic potential for the treatment of VaD caused by chronic cerebral hypoperfusion-associated spontaneous hypertension.

Leukoaraiosis: Epidemiology, Imaging, Risk Factors, and Management of Age-Related Cerebral White Matter Hyperintensities

Leukoaraiosis (LA) manifests as cerebral white matter hyperintensities on T2-weighted magnetic resonance imaging scans and corresponds to white matter lesions or abnormalities in brain tissue. Clinically, it is generally detected in the early 40s and is highly prevalent globally in individuals aged >60 years. From the imaging perspective, LA can present as several heterogeneous forms, including punctate and patchy lesions in deep or subcortical white matter; lesions with periventricular caps, a pencil-thin lining, and smooth halo; as well as irregular lesions, which are not always benign. Given its potential of having deleterious effects on normal brain function and the resulting increase in public health burden, considerable effort has been focused on investigating the associations between various risk factors and LA risk, and developing its associated clinical interventions. However, study results have been inconsistent, most likely due to potential differences in study designs, neuroimaging methods, and sample sizes as well as the inherent neuroimaging heterogeneity and multi-factorial nature of LA. In this article, we provided an overview of LA and summarized the current knowledge regarding its epidemiology, neuroimaging classification, pathological characteristics, risk factors, and potential intervention strategies.

Cognitive performance in children and adolescents with primary hypertension and the role of body mass

Objective

Primary hypertension has been shown to affect cognitive functions in adults but evidence in the pediatric population remain scarce and equivocal. We aimed to compare cognitive functioning between children diagnosed with primary hypertension and normotensive controls, with a focus on the role of different blood pressure (BP) parameters and body mass.

Methods

We conducted a single-center, prospective, cross-sectional study of children and adolescents (6-17 years old) with primary hypertension and age- and sex-matched normotensive controls. All participants underwent office BP, ambulatory BP monitoring (ABPM), and central BP measurements using an oscillometric device. Neurocognitive assessment consisted of evaluation of (i) intelligence quotient (IQ), (ii) categorical and phonemic fluency, (iii) verbal memory (verbal-logical story recall), and (iv) non-verbal computerized cognitive assessment.

Results

The study included a total of 59 patients with primary hypertension (14 ± 3 years) and 37 normotensive controls (14 ± 3 years). Participants in the primary hypertension group had a significantly higher body mass index z-score (BMIz: 2.1 ± 1.4 vs. 0.7 ± 0.9, p < 0.001), and 85% received antihypertensive therapy. Participants with primary hypertension showed worse performance in the domains of reaction speed, attention and processing speed, visual memory, new learning, and phonemic fluency. After adjusting for BMIz, only the differences in the reaction speed tasks remained significant. None of the BP parameters was associated with cognitive outcomes after adjustment for age, sex, and BMIz. BMIz associated with tasks of visual memory, new learning, spatial planning, and working memory, independent of age and sex.

Conclusion

Children and adolescents diagnosed with primary hypertension exhibit worse performance in the cognitive domains of reaction speed, attention, processing speed, visual memory, and new learning. These differences to healthy controls can be partially attributed to accompanying increase of body mass.

[Dementia Prevention]

Dementia is common and will continue to grow in importance and numbers in the future. However, as causal treatment is not possible in most cases, prevention is particularly important. This is not only aimed at cognitively healthy people, but is also a central element in all phases of the disease.

Prevalence and risk factors of cognitive impairment in Chinese patients with hypertension: a systematic review and meta-analysis

Background

Cognitive impairment is prevalent in Chinese patients with hypertension; however, current evidence on prevalence and risk factors is required to be synthesized.

Objectives

This systematic review and meta-analysis aimed to evaluate the prevalence and risk factors of cognitive impairment in Chinese patients with hypertension.

Methods

Two reviewers independently searched PubMed, Web of Science, Embase, The Cochrane Library, CNKI, CBM, the Wanfang database, and the VIP database from their inception to 7 June 2023. The gray literature and the reference lists of the included studies were also retrieved manually. Moreover, we also independently performed the eligibility screening, data extraction, and data synthesis. The primary outcome was the prevalence of cognitive impairment in Chinese patients with hypertension, and the secondary outcomes were the risk factors for cognitive impairment in patients with hypertension. R (version 4.0.3) was used for data synthesis.

Results

In total, 82 studies involving 53,623 patients with hypertension were included in this meta-analysis. The pooled prevalence of cognitive impairment in patients with hypertension was 37.6% (95% CI: 33.2-42.2%). A total of 12 risk factors, including advanced age (r = -0.34, 95% CI: -0.45, -0.21), female sex (OR = 1.15, 95% CI: 1.01-1.32), BMI > 24 Kg/m2 (OR = 1.76, 95% CI: 1.04-3.00), lower educational level (OR = 2.01, 95% CI: 1.10-3.67), single status (OR = 1.63, 95% CI: 1.32-2.02), complications with diabetes (OR = 1.44, 95% CI: 1.14-1.80), coronary heart disease (OR = 1.49, 95% CI: 1.12-1.97), higher stage of hypertension [stage 3 vs. stage 1, OR = 3.08, 95% CI: 1.82-5.22; stage 2 vs. stage 1, OR = 1.83, 95% CI: 1.29-2.60], no regular physical activity (OR = 0.40, 95% CI: 0.21-0.77), higher levels of systolic blood pressure (r = -0.25, 95% CI: -0.42, -0.08), Hcy (r = -0.39, 95% CI: -0.63, -0.09), and IL-6 (r = -0.26, 95% CI: -0.48, -0.02) were detected.

Conclusion

Cognitive impairment is prevalent in Chinese patients with hypertension, and the increased prevalence was associated with several demographic characteristics, complicated disease, no regular physical activity, worse hypertension status (higher stages and SBP), and high levels of biomarkers. Therefore, more attention should be paid to the early identification and treatment of patients with hypertension who are at high risk for cognitive impairment in clinical practice. In addition, relevant risk factors should be controlled to reduce the incidence of cognitive impairment.

Systematic review registration

http://www.crd.york.ac.uk/PROSPERO, identifier [CRD42023410437].

Alterations of White Matter Connectivity in Adults with Essential Hypertension

Purpose

To explore the topology of the white matter network in individuals with essential hypertension by graph theory.

Patients and Methods

T1-weighted image and diffusion tensor imaging (DTI) data from 43 patients diagnosed with essential hypertension (EHT) and 33 individuals with normotension (healthy controls, HCs) were incorporated in this cross-sectional study. Furthermore, structural networks were constructed by graph theory to calculate whole brain network characteristics and intracerebral node characteristics.

Results

Both EHT and HC groups displayed small-worldness in their structural networks. The area under the curve (AUC) of the small-worldness coefficient (σ) was higher in the EHT group compared to the HC group, whereas the AUC of assortativity was lower in the EHT group in contrast to the HC group. The nodal clustering coefficient (CP) and local efficiency (Eloc) of the EHT group decreased in the right dorsolateral superior frontal gyrus and the left medial superior frontal gyrus. These values increased in the left anterior cingulate and paracingulate gyrus. Furthermore, weight and body mass index (BMI) were positively correlated with σ.

Conclusion

The EHT group showed brain network separation and integration dysfunction. Weight and BMI were positively correlated with σ. The data acquired in this investigation implied that altered structural connectivity in the prefrontal region may be a potential neuroimaging marker in EHT patients.

Hypertension and Mild Cognitive Impairment: Understanding the Complexities of the Relationship in Understudied Populations

The association between hypertension and mild cognitive impairment (MCI) is complex. Both are increasing in prevalence worldwide and will have disproportionate effects on lower income countries across Latin America. Despite this, there is insufficient evidence investigating this relationship in this region or those of Hispanic or Latino ancestry in higher income countries. In this context, the Study of Latinos-Investigation of Neurocognitive Aging represents a unique dataset. Although more research is required, Márquez and colleagues show that hypertension in this population in the United States is associated with decline in cognitive measures and greater odds of MCI over seven years follow-up.

Late-life food insecurity and cognition: exploring timing, duration, and mechanisms among older Mexican adults

BACKGROUND

Food insecurity (FI) remains a global public health problem. FI is more prevalent in low-and middle-income countries than high-income countries. FI is related with worse cognitive outcomes including cognitive function, cognitive decline, and cognitive impairment. Few studies have sought to identify how patterns of FI relate with cognitive function in old age and the potential mechanisms underlying this association.

METHODS

Data from the 2015 and 2018 waves of the Mexican Health and Aging Study (n = 9,654, age 50+) were used in this study. Reports of FI in 2015 and 2018 were combined to create four patterns of FI groups: "persistently food secure", "became food secure", "became food insecure", and "persistently food insecure". Linear regression was used to estimate associations between patterns of FI and cognitive task performance. The mediating roles of depressive symptoms, body mass index, and chronic conditions were tested using Karlson, Holm, and Breen methodology.

RESULTS

Approximately half of the sample were persistently food secure, 17% became food secure, 14% became FI, and 15% experienced persistent FI. When adjusting for demographic/socioeconomic confounders, persistent FI related with worse Verbal Learning, Verbal Recall, Visual Scanning, and Verbal Fluency performance compared to the persistently food secure. Becoming FI related with worse Verbal Learning, Visual Scanning, and Verbal Fluency. Mediation analyses provided support for depressive symptoms mediating associations between FI and poorer cognition, where 48% of the association between persistent FI and worse Verbal Recall performance was attributed to higher depressive symptoms. Becoming food secure was not associated with cognitive performance compared to the persistently food secure.

CONCLUSIONS

FI may represent an important modifiable risk factor for poorer cognitive outcomes among older adults. Public health efforts should focus on providing stable food access to older adults, especially those living in poverty.

Association of medication adherence quality measures for diabetes, hypertension, and hyperlipidemia with cognitive decline

Background

While diabetes, hypertension, and hyperlipidemia each are associated with increased risk of cognitive decline, little is known regarding how nonadherence to medications for these conditions is associated with cognitive decline risk.

Methods

We identified patients enrolled in a Medicare Advantage Prescription Drug plan who were eligible for inclusion in the CMS Star Medication Adherence quality measures for diabetes, hypertension, and hyperlipidemia in 2018, 2019, and 2020. To achieve an adherence quality measure, patients had to meet 80% of the proportion of days for the medication. We used propensity score with inverse probability of treatment weighting to balance outcomes for baseline characteristics and logistic regression models to compare odds of cognitive decline outcomes across patient groups.

Results

The study population of 99,774 individuals had a mean age of 71.0 years and was 49.1% female, 73.9% White, and 17.8% Black, with 62.0% living in an urban setting. Compared with patients who missed zero adherence measures, those who missed one measure had 23%-33% increased odds of cognitive decline (any decline OR = 1.23; dementia OR = 1.33; Alzheimer's disease OR = 1.27; all P values <0.01). Patients who missed 2-3 measures had 37%-96% increased odds of cognitive decline (any decline OR = 1.37; dementia OR = 1.58; Alzheimer's disease OR = 1.96; all P values <0.01). Patients who missed ≥4 adherence measures had the greatest odds of cognitive decline (any decline OR = 1.64; dementia OR = 2.05; Alzheimer's disease OR = 2.48; all P values <0.01).

Conclusion

Not achieving CMS Star Medication Adherence quality measures for diabetes, hypertension, and hyperlipidemia therapies was associated with increased risk of cognitive decline outcomes.

Association between Dietary Patterns and Cognitive Function among Qatari Adults: A Cross-Sectional Analysis of the Qatar Biobank Study

This study aimed to assess the association between dietary patterns and cognitive function among Qatari adults. In a cross-sectional analysis, data on 1000 Qatari adults attending the Qatar Biobank Study (QBB) aged ≥18 years were obtained. Using factor analysis, dietary patterns were constructed based on habitual dietary intake assessed by food frequency questionnaires (FFQs). The mean reaction time (MRT) derived from self-administered touch screen tests was used as an indicator of cognitive function. The association between dietary patterns and MRT was investigated using linear regression. The mean age of the participants was 35.8 (SD 10.3) years, and the mean MRT was 715.3 (SD 204.1) milliseconds. Three dietary patterns were identified. The "traditional" dietary pattern, characterized by high intakes of white rice, mixed dishes and soups/starters possibly high in saturated fat and sodium, was positively associated with MRT. In the multivariable model, comparing the highest to lowest quartiles of the traditional pattern, the regression coefficient for MRT was 50.0 (95% CI 16.9, 83.1; p for trend 0.001). There was an effect modification of diabetes and age on the association between the "modern" dietary pattern and MRT. The "convenient" dietary pattern was not associated with cognition. In conclusion, the traditional rice-based dietary pattern may be associated with poor cognitive function.

Longitudinal trajectories of memory among middle-aged and older people with hearing loss: the influence of cochlear implant use on cognitive functioning

Introduction

Cochlear implants (CI) are the gold standard intervention for severe to profound hearing loss, a known modifiable risk factor for dementia. However, it remains unknown whether CI use might prevent the age-related cognitive decline. Recent studies are encouraging but are limited, mainly by short follow-up periods and, for ethical reasons, lack of appropriate control groups. Further, as age-related cognitive decline is multifaceted and not linear, other statistical approaches have to be evaluated.

Materials and methods

Immediate and delayed recall as measures of cognitive function were assessed in 75 newly implanted CI users (mean age 65.41 years ± 9.19) for up to 5 years (mean 4.5 ± 0.5) of CI use and compared to 8,077 subjects of the same age range from two longitudinal cohort studies, the Health and Retirement Study (HRS) and the English Longitudinal Study of Aging (ELSA). Linear and quadratic changes in cognitive trajectories were analyzed in detail using mixed growth models, considering possible confounders.

Results

For CI users, the linear time slope showed a significant improvement in the specific domains (recall and delayed recall) over time. The quadratic time slope clearly indicated that the predicted change after CI provision followed an inverted U-shape with a predicted decline 2 years after CI provision. In the hearing-impaired group, a significant decline over time was found, with steeper declines early on and the tendency to flatten out in the follow-up.

Conclusion

Cochlear implant use seems to boost cognitive trajectories in the first years after implantation. However, long-term prevention of dementia seems to need far more than restoration of hearing loss.

Life's Essential 8: Optimizing Health in Older Adults

The population worldwide is getting older as a result of advances in public health, medicine, and technology. Older individuals are living longer with a higher prevalence of subclinical and clinical cardiovascular disease (CVD). In 2010, the American Heart Association introduced a list of key prevention targets, known as "Life's Simple 7" to increase CVD-free survival, longevity, and quality of life. In 2022, sleep health was added to expand the recommendations to "Life's Essential 8" (eat better, be more active, stop smoking, get adequate sleep, manage weight, manage cholesterol, manage blood pressure, and manage diabetes). These prevention targets are intended to apply regardless of chronologic age. During this same time, the understanding of aging biology and goals of care for older adults further enhanced the relevance of prevention across the range of functions. From a biological perspective, aging is a complex cellular process characterized by genomic instability, telomere attrition, loss of proteostasis, inflammation, deregulated nutrient-sensing, mitochondrial dysfunction, cellular senescence, stem cell exhaustion, and altered intercellular communication. These aging hallmarks are triggered by and enhanced by traditional CVD risk factors leading to geriatric syndromes (eg, frailty, sarcopenia, functional limitation, and cognitive impairment) which complicate efforts toward prevention. Therefore, we review Life's Essential 8 through the lens of aging biology, geroscience, and geriatric precepts to guide clinicians taking care of older adults.

Validation of the German Montreal-Cognitive-Assessment-H for hearing-impaired

Background

Hearing loss and dementia are highly prevalent in older age and often co-occur. Most neurocognitive screening tests are auditory-based, and performance can be affected by hearing loss. To address the need for a cognitive screening test suitable for people with hearing loss, a visual version of the Montreal-Cognitive-Assessment was developed and recently validated in English (MoCA-H), with good sensitivity and specificity for identifying cases of dementia. As the MoCA is known to perform differently across languages, revalidation of the German MoCA-H was necessary. The aim of the present study was to assess the diagnostic accuracy of the German MoCA-H among those with normal cognition, mild cognitive impairment (MCI) and dementia and to determine an appropriate performance cut- off.

Materials and methods

A total of 346 participants aged 60-97 years (M = 77.18, SD = 9.56) were included; 160 were cognitively healthy, 79 with MCI and 107 were living with dementia based on the GPCOG and a detailed medical questionnaire as well as a comprehensive examination by a neurologist in case of cognitive impairment. Performance cut-offs for normal cognition, MCI and dementia were estimated for the MoCA-H score and z-scores using the English MoCA-H cut-off, the balanced cut-off and the Youden's Index.

Results

A mean score of 25.49 (SD = 3.01) points in the German MoCA-H was achieved in cognitively healthy participants, 20.08 (SD = 2.29) in the MCI and 15.80 (SD = 3.85) in the dementia group. The optimum cut-off for the detection of dementia was ≤21 points with a sensitivity of 96.3% and a specificity of 90%. In the MCI group, a cut-off range between 22 and 24 points is proposed to increase diagnostic accuracy to a sensitivity and specificity of 97.5 and 90%, respectively.

Conclusion

The German MoCA-H seems to be a sensitive screening test for MCI and dementia and should replace commonly used auditory-based cognitive screening tests in older adults. The choice of a cut-off range might help to better reflect the difficulty in clinical reality in detecting MCI. However, screening test batteries cannot replace a comprehensive cognitive evaluation.

Computerized working memory training for hypertensive individuals with executive function impairment: a randomized clinical trial

Background

Hypertension is associated with working memory (WM) impairment. However, the benefits of Cogmed WM training for the hypertensive population are unknown. Therefore, we aimed to evaluate Cogmed's effects on the WM performance of hypertensive individuals with executive function (EF) impairment.

Methods

We included 40 hypertensive patients (aged 40-70 years, 68% female) with EF impairment. They were randomized in a 1:1 ratio to receive 10 weeks of adaptive Cogmed training or a non-adaptive control training based on online games. The primary outcome was the WM performance. The secondary outcomes were verbal memory, visuospatial ability, executive function, global cognition, and the neuronal activity measured using functional magnetic resonance imaging (fMRI) under two WM task conditions: low (memorization of 4 spatial locations) and high (memorization of 6 spatial locations). An intention-to-treat (ITT) and per-protocol (PP) analysis were performed.

Results

Cogmed did not show a significant effect on WM or any other cognitive outcome post-training. However, under the WM-low load and WM-high load conditions of the fMRI, respectively, the Cogmed group had an activation decrease in the right superior parietal lobe (ITT and PP analyses) and left inferior frontal lobe (PP analysis) in comparison to the control group.

Conclusion

The Cogmed showed no effects on the WM performance of hypertensive individuals with EF impairment. However, activation decreases were observed in frontoparietal areas related to the WM network, suggesting a more efficient neuronal activity after training.

The A-to-Z factors associated with cognitive impairment. Results of the DeCo study

Introduction

Cognitive impairment (CI) is known to be mediated by several risk and protective factors, many of which are potentially modifiable. Therefore, it is important to have up-to-date studies that address a standard assessment of psychosocial, clinical and lifestyle variables.

Materials and methods

We conducted a cross-sectional observational study, with a 24-month timeframe, to estimate the relationship between risk and protective factors associated with dementia, according to the A-to-Z Dementia Knowledge. Participants were considered at CI risk if they tested positive for at least one of three validated CI screening tests: The Memory Impairment Screening, Short Portable Mental State Questionnaire, and Semantic Verbal Fluency. The A-to-Z data Collection included Mediterranean Diet Adherence Screener and Geriatric Depression Scale.

Results

The estimated prevalence of CI was 22.6% in a sample of 709 patients with an average of 69.3±10.3 years. The risk factors gradually associated with cognitive decline were hypertension, loneliness, and depression. In contrast, the protective factors gradually associated with less cognitive decline were internet use, reading, and intellectually stimulating jobs. Finally, living alone, having diabetes, taking benzodiazepines, and sleeping more than 9 h were statistically significant associated with CI, whereas to do memory training or a family history of dementia was characteristic of patients without CI.

Conclusion

A joint assessment of the influence of psychosocial, clinical, and lifestyle-related factors is needed to develop dementia prevention strategies.

Longitudinal characterization of cerebral hemodynamics in the TgF344-AD rat model of Alzheimer's disease

Alzheimer's disease (AD) is a global healthcare crisis. The TgF344-AD rat is an AD model exhibiting age-dependent AD pathological hallmarks. We confirmed that AD rats developed cognitive deficits at 6 months without alteration of any other major biophysical parameters. We longitudinally characterized cerebral hemodynamics in AD rats at 3, 4, 6, and 14 months. The myogenic responses of the cerebral arteries and arterioles were impaired at 4 months of age in the AD rats. Consistent with the ex vivo results, the AD rat exhibited poor autoregulation of surface and deep cortical cerebral blood flow 2 months preceding cognitive decline. The dysfunction of cerebral hemodynamics in AD is exacerbated with age associated with reduced cerebral perfusion. Further, abolished cell contractility contributes to cerebral hemodynamics imbalance in AD. This may be attributed to enhanced ROS production, reduced mitochondrial respiration and ATP production, and disrupted actin cytoskeleton in cerebral vascular contractile cells.

Population attributable fraction of hypertension for dementia: global, regional, and national estimates for 186 countries

Background

Quantifying the proportion of dementia attributable to highly prevalent modifiable risk factors, such as hypertension, is important in informing effective dementia prevention strategies. We aim to quantify the population attributable fraction (PAF) of hypertension for dementia (the proportion of dementia cases that would not occur if hypertension was eliminated) at global, regional, and national levels.

Methods

In this study, we searched international and governmental websites for global, regional, and national data reporting population hypertension (according to 10-year age categories) and dementia prevalence. MEDLINE was searched for studies reporting the risk of dementia from age at hypertension diagnosis from database inception to December 31, 2022. Longitudinal observational studies with >500 participants reporting hazard ratios by age at hypertension diagnosis for risk of future all-cause dementia were eligible for inclusion. Studies excluded had cross-sectional methodology, specific vascular dementia or 'cognitive impairment' outcomes, and no age-specific metrics of association reported. The PAF of hypertension for dementia was calculated globally and for each country and region worldwide.

Findings

Data from the Global Burden of Disease, United Nations Population Prospectus, NCD Risk Factor Collaboration, UK Biobank, and Atherosclerosis Risk in Communities Study were obtained. 186 countries reported dementia and hypertension prevalence data. The global PAF of hypertension for dementia was 15.8% [95% Credible Interval (CI), 8.8%-22.7%]. Latin America and the Caribbean (18.0% [95% CI, 9.4%-26.6%]), and Europe (17.2% [95% CI, 9.6%-24.7%]) had the highest PAF of hypertension for dementia. Hypertension diagnosed between the ages of 30-44 had the highest age-specific global attributable fraction for dementia (8.4% [95% CI, 3.4%-13.5%]), followed by ages 45-54 (2.92% [ 95% CI, 0.96%-4.88%]), 55-64 (2.59% [95% CI, 1.15%-4.03%]) and 65-74 (1.82% [95% CI, -2.31%-5.96%]).

Interpretation

The population attributable risk of hypertension for dementia is 15.8%, suggesting that optimal detection and treatment, particularly at midlife, has the potential to markedly reduce the global burden of dementia.

Funding

Wellcome Trust; Health Research Board of Ireland; Alzheimer's Association.

Epigenetic Signatures in Hypertension

Clear epigenetic signatures were found in hypertensive and pre-hypertensive patients using DNA methylation data and neural networks in a classification algorithm. It is shown how by selecting an appropriate subset of CpGs it is possible to achieve a mean accuracy classification of 86% for distinguishing control and hypertensive (and pre-hypertensive) patients using only 2239 CpGs. Furthermore, it is also possible to obtain a statistically comparable model achieving an 83% mean accuracy using only 22 CpGs. Both of these approaches represent a substantial improvement over using the entire amount of available CpGs, which resulted in the neural network not generating accurate classifications. An optimization approach is followed to select the CpGs to be used as the base for a model distinguishing between hypertensive and pre-hypertensive individuals. It is shown that it is possible to find methylation signatures using machine learning techniques, which can be applied to distinguish between control (healthy) individuals, pre-hypertensive individuals and hypertensive individuals, illustrating an associated epigenetic impact. Identifying epigenetic signatures might lead to more targeted treatments for patients in the future.

Effects of Melissa officinalis Extract Containing Rosmarinic Acid on Cognition in Older Adults Without Dementia: A Randomized Controlled Trial

BACKGROUND

Previous in vitro and in vivo studies on Alzheimer's disease (AD) models have reported that rosmarinic acid (RA) can inhibit the formation of amyloid-β fibrils as well as the oligomerization and deposition of amyloid-β protein. Melissa officinalis (M. officinalis) extract containing 500 mg of RA is tolerable and safe in healthy individuals and patients with mild AD dementia.

OBJECTIVE

This randomized placebo-controlled double-blind trial aimed to assess the effects of M. officinalis extract on cognition in older adults without dementia.

METHODS

This study included individuals who were diagnosed with subjective or mild cognitive impairment (n = 323). The trial involved M. officinalis extract supplementation (500 mg of RA per day) period of 96 weeks followed by a washout period of 24 weeks. The primary endpoint was the Alzheimer's Disease Assessment Scale-cognitive subscale score, and the secondary endpoints were other cognitive measure results as well as safety and tolerability.

RESULTS

There were no significant differences in cognitive measures between the placebo and M. officinalis groups from baseline to 96 weeks. However, based on the analysis of Clinical Dementia Rating Sum of Boxes scores in participants without hypertension, the score was found to be increased by 0.006 and decreased by 0.085 in the M. officinalis and placebo groups, respectively; this difference was statistically significant (p = 0.036). Furthermore, there were no differences in vital signs, physical and neurological measures, or hippocampal volume between the two groups.

CONCLUSION

These results indicate that M. officinalis extract may help prevent cognitive decline in older adults without hypertension.

Identification of the molecular mechanism of insulin-like growth factor-1 (IGF-1): a promising therapeutic target for neurodegenerative diseases associated with metabolic syndrome

Neurodegenerative disorders are accompanied by neuronal degeneration and glial dysfunction, resulting in cognitive, psychomotor, and behavioral impairment. Multiple factors including genetic, environmental, metabolic, and oxidant overload contribute to disease progression. Recent evidences suggest that metabolic syndrome is linked to various neurodegenerative diseases. Metabolic syndrome (MetS) is known to be accompanied by symptoms such as hyperglycemia, abdominal obesity, hypertriglyceridemia, and hypertension. Despite advances in knowledge about the pathogenesis of neurodegenerative disorders, effective treatments to combat neurodegenerative disorders caused by MetS have not been developed to date. Insulin growth factor-1 (IGF-1) deficiency has been associated with MetS-related pathologies both in-vivo and in-vitro. IGF-1 is essential for embryonic and adult neurogenesis, neuronal plasticity, neurotropism, angiogenesis, metabolic function, and protein clearance in the brain. Here, we review the evidence for the potential therapeutic effects of IGF-1 in the neurodegeneration related to metabolic syndrome. We elucidate how IGF-1 may be involved in molecular signaling defects that occurs in MetS-related neurodegenerative disorders and highlight the importance of IGF-1 as a potential therapeutic target in MetS-related neurological diseases.

Cognitive impairment in patients with heart failure: molecular mechanism and therapy

Heart failure (HF) is associated with multiple organ dysfunction and many comorbidities. Its incidence is high among the elderly and is a major health burden worldwide. Cognitive impairment (CI) is highly prevalent in older patients with HF, which is an abnormality in one or more of the items of cognition, attention, memory, language, psychomotor function, and visual spatial acuity. Studies have shown that the incidence of CI in HF patients is between 13 and 54%, and patients with both conditions have poor self-care ability and prognosis, as well as increased mortality rates. However, the mechanisms of CI development in HF patients are still unclear. In this review, we describe the epidemiology and risk factors as well as measures of improving CI in HF patients. We update the latest pathophysiological mechanisms related to the neurocognitive changes in HF patients, expounding on the mechanisms associated with the development of CI in HF patients.

Alterations to Cerebral Perfusion, Metabolite Profiles, and Neuronal Morphology in the Hippocampus and Cortex of Male and Female Mice during Chronic Exposure to a High-Salt Diet

Excess dietary salt reduces resting cerebral blood flow (CBF) and vascular reactivity, which can limit the fueling of neuronal metabolism. It is hitherto unknown whether metabolic derangements induced by high-salt-diet (HSD) exposure during adulthood are reversed by reducing salt intake. In this study, male and female mice were fed an HSD from 9 to 16 months of age, followed by a normal-salt diet (ND) thereafter until 23 months of age. Controls were continuously fed either ND or HSD. CBF and metabolite profiles were determined longitudinally by arterial spin labeling magnetic resonance imaging and magnetic resonance spectroscopy, respectively. HSD reduced cortical and hippocampal CBF, which recovered after dietary salt normalization, and affected hippocampal but not cortical metabolite profiles. Compared to ND, HSD increased hippocampal glutamine and phosphocreatine levels and decreased creatine and choline levels. Dietary reversal only allowed recovery of glutamine levels. Histology analyses revealed that HSD reduced the dendritic arborization and spine density of cortical and hippocampal neurons, which were not recovered after dietary salt normalization. We conclude that sustained HSD exposure throughout adulthood causes permanent structural and metabolic alterations to the mouse brain that are not fully normalized by lowering dietary salt during aging.

The Impact of Intermittent Hypoxia on Metabolism and Cognition

Intermittent hypoxia (IH), one of the primary pathologies of sleep apnea syndrome (SAS), exposes cells throughout the body to repeated cycles of hypoxia/normoxia that result in oxidative stress and systemic inflammation. Since SAS is epidemiologically strongly correlated with type 2 diabetes/insulin resistance, obesity, hypertension, and dyslipidemia included in metabolic syndrome, the effects of IH on gene expression in the corresponding cells of each organ have been studied intensively to clarify the molecular mechanism of the association between SAS and metabolic syndrome. Dementia has recently been recognized as a serious health problem due to its increasing incidence, and a large body of evidence has shown its strong correlation with SAS and metabolic disorders. In this narrative review, we first outline the effects of IH on the expression of genes related to metabolism in neuronal cells, pancreatic β cells, hepatocytes, adipocytes, myocytes, and renal cells (mainly based on the results of our experiments). Next, we discuss the literature regarding the mechanisms by which metabolic disorders and IH develop dementia to understand how IH directly and indirectly leads to the development of dementia.

Blood pressure control and risk of post-stroke dementia among the elderly: A population-based screening study

Background

Post-stroke dementia (PSD) has adverse effects on the quality of work and life in elderly stroke survivors. There are inconsistent results on the impacts of blood pressure control on the risk of PSD in people aged 65 years and above.

Objective

This study was performed to explore whether poorly-controlled blood pressure was associated with an increasing risk of PSD.

Methods

The study population was enrolled from cross-sectional research conducted in 106 communities of rural northern China. In Phase I, a total of 7,448 people aged ≥65 years, including 830 with stroke history, completed a questionnaire, a physical examination, and a cognitive assessment. Phase II further confirmed the diagnosis of PSD. Well-controlled blood pressure was defined as an average systolic blood pressure of &lt;140 mmHg and average diastolic blood pressure of &lt;90 mmHg over two readings in person. Failure to meet these criteria was considered as poorly-controlled blood pressure.

Results

The crude prevalence rate of PSD among stroke survivors aged 65 years and over was 17.8% [95% confidence interval (CI) 15.2–20.4%]. Among the 830 stroke survivors, the proportions of PSD gradually increased with age and the crude prevalence rates for PSD were 10.2% (95% CI 5.6–14.9%), 14.8% (95% CI 10.1–19.5%), 18.8% (95% CI 14.1–23.5%), and 27.4% (95% CI 20.8–34.1%) in subjects aged 65–69, 70–74, 75–79 and ≥80 years, respectively. Participants in the poorly-controlled blood pressure group were more likely to suffer from PSD (28.4 vs.15.3%, P &lt; 0.001), be older (75.81 ± 4.97 vs. 74.74 ± 5.83, P &lt; 0.05), and have a worse cognitive level (22.26 ± 7.05 vs. 24.10 ± 6.02, P &lt; 0.05). Compared with well-controlled blood pressure patients, poorly-controlled blood pressure in stroke survivors significantly increased risk of PSD (odds ratio = 2.20, 95% CI 1.45–3.32) after adjusting for age, gender, and education.

Conclusions

The crude prevalence of PSD among stroke survivors aged ≥65 years was 17.8% at community level. In addition to lower education level and older age, poorly-controlled blood pressure was also an independent risk factor for PSD among the elderly, which is amenable to intervention. Therefore, it is essential to control blood pressure to reduce PSD incidence.