Blood pressure and cognitive performances in middle-aged adults: the Aging, Health and Work longitudinal study

Development and Validation of a Predictive Model for Early Identification of Cognitive Impairment Risk in Community-Based Hypertensive Patients

Objective: To investigate the risk factors for the development of mild cognitive dysfunction in hypertensive patients in the community and to develop a risk prediction model. Method: The data used in this study were obtained from two sources: the China Health and Retirement Longitudinal Study (CHARLS) and the Chinese Longitudinal Healthy Longevity Survey (CLHLS). A total of 1121 participants from CHARLS were randomly allocated into a training set and a validation set, following a 70:30 ratio. Meanwhile, an additional 4016 participants from CLHLS were employed for external validation of the model. The patients in this study were divided into two groups: those with mild cognitive impairment and those without. General information, employment status, pension, health insurance, and presence of depressive symptoms were compared between the two groups. LASSO regression analysis was employed to identify the most predictive variables for the model, utilizing 14-fold cross-validation. The risk prediction model for cognitive impairment in hypertensive populations was developed using generalized linear models. The model's discriminatory power was evaluated through the area under the receiver operating characteristic (ROC) curve and calibration curves. Results: In the modeling group, eight variables such as gender, age, residence, education, alcohol use, depression, employment status, and health insurance were ultimately selected from an initial pool of 21 potential predictors to construct the risk prediction model. The area under the curve (AUC) values for the training, internal, and external validation sets were 0.777, 0.785, and 0.782, respectively. All exceeded the threshold of 0.7, suggesting that the model effectively predicts the incidence of mild cognitive dysfunction in community-based hypertensive patients. A risk prediction model was developed using a generalized linear model in conjunction with Lasso regression. The model's performance was evaluated using the area under the receiver operating characteristic (ROC) curve. Hosmer-Lemeshow test values yielded p = .346 and p = .626, both of which exceeded the 0.05 threshold. Calibration curves demonstrated a significant agreement between the nomogram model and observed outcomes, serving as an effective tool for evaluating the model's predictive performance. Discussion: The predictive model developed in this study serves as a promising and efficient tool for evaluating cognitive impairment in hypertensive patients, aiding community healthcare workers in identifying at-risk populations.

Analysis of the relationship between blood pressure variability and subtle cognitive decline in older adults

BACKGROUND

Blood pressure variability (BPV) has been shown to be related to mild cognitive impairment and Alzheimer's disease in a number of studies. However, the relationship between BPV and subtle cognitive decline (SCD) has received minimal attention in this field of research to date and has rarely been reported.

AIM

To examine whether SCD is independently associated with changes in BPV in older adults.

METHODS

Participants were selected based on having participated in cognitive function evaluation and ambulatory blood pressure measurement at the Shanghai Sixth People's Hospital Affiliated with Shanghai Jiao Tong University School of Medicine between June 2020 and August 2022. The participants included 182 individuals with SCD as the experimental group and 237 with normal cognitive function as the control group. The basic data, laboratory examinations, scale tests, and ambulatory blood pressure test results of the two groups were analyzed retrospectively, and the relationship between SCD and BPV was subsequently evaluated.

RESULTS

Significant differences were observed between the two groups of participants (P < 0.05) in terms of age, education level, prevalence rate of diabetes, fasting blood glucose level, 24-h systolic blood pressure standard deviation and coefficient of variation, 24-h diastolic blood pressure standard deviation and coefficient of variation. The scale monitoring results showed significant differences in the scores for memory, attention, and visual space between the experimental and control groups. Logistic regression analysis indicated that age, education level, blood sugar level, and BPV were factors influencing cognitive decline. Linear regression analysis showed that there was an independent correlation between blood pressure variation and SCD, even after adjusting for related factors. Each of the above differences was still significant.

CONCLUSION

This study suggests that increased BPV is associated with SCD.

Mechanisms underlying HIV-associated cognitive impairment and emerging therapies for its management

People living with HIV are affected by the chronic consequences of neurocognitive impairment (NCI) despite antiretroviral therapies that suppress viral replication, improve health and extend life. Furthermore, viral suppression does not eliminate the virus, and remaining infected cells may continue to produce viral proteins that trigger neurodegeneration. Comorbidities such as diabetes mellitus are likely to contribute substantially to CNS injury in people living with HIV, and some components of antiretroviral therapy exert undesirable side effects on the nervous system. No treatment for HIV-associated NCI has been approved by the European Medicines Agency or the US Food and Drug Administration. Historically, roadblocks to developing effective treatments have included a limited understanding of the pathophysiology of HIV-associated NCI and heterogeneity in its clinical manifestations. This heterogeneity might reflect multiple underlying causes that differ among individuals, rather than a single unifying neuropathogenesis. Despite these complexities, accelerating discoveries in HIV neuropathogenesis are yielding potentially druggable targets, including excessive immune activation, metabolic alterations culminating in mitochondrial dysfunction, dysregulation of metal ion homeostasis and lysosomal function, and microbiome alterations. In addition to drug treatments, we also highlight the importance of non-pharmacological interventions. By revisiting mechanisms implicated in NCI and potential interventions addressing these mechanisms, we hope to supply reasons for optimism in people living with HIV affected by NCI and their care providers.

Cross-sectional associations between short and mid-term blood pressure variability, cognition, and vascular stiffness in older adults

Background

High blood pressure variability (BPV), particularly in older age, appears to be an independent risk factor for incident dementia. The current study aimed to investigate the association between different BPV measures (short- and mid-term BPV including circadian patterns) and cognitive functioning as well as vascular stiffness measures to better understand the role that BPV plays in cognitive impairment.

Methods

70 older adults (60-80-year-olds) without dementia completed a cognitive test battery and had their blood pressure (BP) assessed via a 24-hour ambulatory BP monitor (divided into sleep and wake for short-term BPV) and 4-day morning and evening home-based BP monitor (for day-to-day BPV). Arterial stiffness was evaluated via pulse wave analysis and pulse wave velocity (PWV) and cerebrovascular pulsatility was assessed via transcranial doppler sonography of the middle cerebral arteries.

Results

High systolic as well as diastolic short- and mid-term BPV were associated with poorer cognitive functioning, independent of the mean BP. Higher short-term BPV was associated with poorer attention and psychomotor speed, whilst day-to-day BPV was negatively linked with executive functioning. Circadian BP patterns (dipping and morning BP surge) showed no significant relationships with cognition after adjusting for covariates. Higher systolic short-term BPV was associated with higher arterial stiffness (PWV) and higher diastolic day-to-day BPV was linked with lower arterial stiffness. No significant associations between BPV measures and cerebrovascular pulsatility were present.

Conclusion

High BPV, independently of the mean BP, is associated with lower cognitive performance and increased arterial stiffness in older adults without clinically-relevant cognitive impairment. This highlights the role of systolic and diastolic BPV as a potential early clinical marker for cognitive impairment.

Treatment of hypertension and obstructive sleep apnea counteracts cognitive decline in common neurocognitive disorders in diagnosis-related patterns

The aim of this study was to investigate the effect of arterial hypertension (AH) and of obstructive sleep apnea (OSA) on cognitive course in the neurocognitive disorder (NCD) cohort RIFADE which enrolled patients with NCD due to Alzheimer's disease (AD), vascular NCD (vNCD), and mixed NCD (AD + vNCD = mNCD). Multiple risk factors (RF), including AH and OSA, that contribute to the development of various kinds of dementia have been identified in previous studies. Studies that observed AH lacked investigation of long-term effects and did not isolate it from other RF. Studies involving OSA as a risk factor did not include participants with all stages of NCD. 126 subjects were screened for AH and OSA. Repeated cognitive measurements were performed with the DemTect as primary outcome and the clock drawing test as secondary outcome measure. 90 patients had AH (71.4%) and 40 patients had OSA (31.7%). RF-status had a significant effect on cognitive outcome in models with RF as single factors (AH p = 0.027, OSA p < 0.001), a 2-factor analysis with AH × OSA (AH as main factor p = 0.027) as well as a model including the 3 factors AH × OSA × diagnosis (p = 0.038). Similarly, a 3-factor model was significant for the clock-drawing test, whereas single factor-models remained insignificant. AH and OSA appear to be risk factors in common NCD and cognitive decline can be mitigated by treatment of these RF.

Association between blood pressure control status, visit-to-visit blood pressure variability, and cognitive function in elderly Chinese: A nationwide study

Background

Cognitive function is a concern among the elderly, which is related to the quality of life, life expectancy, and economic burdens. The relationship between blood pressure (BP) control status, visit-to-visit BP variability, and cognitive function remains controversial.

Methods

We aimed to explore the association between BP control status at baseline, visit-to-visit BP variability, and cognitive function. This study included 3,511 elderlies in the China Health and Retirement Longitudinal Study, covering four waves for 7-year follow-up (baseline 2011, 2013, 2015, and 2018). BP was measured in Wave 2011, 2013, and 2015. Cognitive function was measured by Mini-Mental State Exam in Wave 2018. Participants were divided into two groups: mid-old group for reflecting midlife BP and cognition (45–59 years at baseline but aged 60 or over in Wave 2018), and old-old group for reflecting late-life BP and cognition (aged 60 or over at baseline). We use univariate analysis and general linear model to analyze.

Results

Late-life BP showed stronger associations with cognitive function than midlife BP. As to late-life BP control status, controlled hypertension group get higher cognitive score than uncontrolled hypertension group in language (adjusted β = −0.34, 95%CI −0.68 to 0.00), and untreated hypertension group in orientation (adjusted β = −0.41, 95%CI −0.72 to −0.11), language (adjusted β = −0.35, 95%CI −0.67 to −0.04), and total (adjusted β = −0.99, 95%CI −1.85 to −0.12). Regarding visit-to-visit BP variability, midlife visit-to-visit systolic blood pressure (SBP) variability was associated with language (adjusted β = −3.70, 95% CI −5.83 to −1.57), while late-life visit-to-visit SBP variability was associated with orientation (adjusted β = −2.99, 95% CI −4.84 to −1.14), recall (adjusted β = −1.69, 95% CI −2.89 to −0.48), language (adjusted β = −2.26, 95% CI −4.13 to −0.38), and total (adjusted β = −9.50, 95% CI −14.71 to −4.28); Midlife diastolic blood pressure (DBP) variability and pulse pressure (PP) variability showed a significant relationship with language (adjusted β = 3.25, 95% CI −1.31 to −5.19) and calculation (adjusted β = −0.26, 95% CI −0.47 to −0.04), respectively. No significant correlation was found between midlife BP control status, late-life visit-to-visit DBP variability, late-life visit-to-visit PP variability, and cognitive score. There was no significant correlation between BP and memory.

Conclusions

BP control status and visit-to-visit BP variability were significantly related to cognitive function among the Chinese elderly. Receiving effective late-life antihypertensive treatment and keeping SBP stable might contribute to prevent the development of cognitive impairment and dementia, especially for orientation and language function.

Diastolic Blood Pressure Variability in Later Life May Be a Key Risk Marker for Cognitive Decline

BACKGROUND

There is an increasing awareness of the need to understand the interaction between long-term blood pressure patterns and their impact on the brain and cognition.

METHODS

Our aim was to investigate the relationship between repeated blood pressure measures and change in cognitive performance over 12 years and imaging data at 12 years using a longitudinal population study. The data consisted of 2 cohorts, one midlife and one later life. Using linear regression, we examined the relationship between blood pressure (systolic, diastolic, change in blood pressure between visits, and visit-to-visit variability), change in cognitive performance and imaging at 12 years.

RESULTS

Data on cognitive change were available in 1054 at midlife, baseline age 42.7 (SD 1.5) and 1233 in later life, 62.5 (1.5) years. Imaging data were available in 168 and 233, respectively. After adjustment for multiple comparisons greater diastolic blood pressure variability in later life was associated with a -1.95 point decline (95% CI, -2.89 to -1.01) on an attention-based task and a -0.42 point (95% CI, -0.68 to -0.15) decline in performance on a psychomotor task. A higher SD in diastolic pressure across follow-up was associated with greater white matter hyperintensity volume (%increase per 10 mm Hg increase in the SD [1.50 (95% CI, 1.16-1.94]).

CONCLUSIONS

In a largely normotensive/mildly hypertensive population, our analyses reported no relationships between blood pressure and cognition in midlife but a potential role for diastolic blood pressure variability in later life as a risk marker for cognitive decline. This may indicate an at-risk period or a means to identify an at-risk population at the age where diastolic pressure is starting to decline.

Recent Neurotherapeutic Strategies to Promote Healthy Brain Aging: Are we there yet?

Owing to the global exponential increase in population ageing, there is an urgent unmet need to develop reliable strategies to slow down and delay the ageing process. Age-related neurodegenerative diseases are among the main causes of morbidity and mortality in our contemporary society and represent a major socio-economic burden. There are several controversial factors that are thought to play a causal role in brain ageing which are continuously being examined in experimental models. Among them are oxidative stress and brain inflammation which are empirical to brain ageing. Although some candidate drugs have been developed which reduce the ageing phenotype, their clinical translation is limited. There are several strategies currently in development to improve brain ageing. These include strategies such as caloric restriction, ketogenic diet, promotion of cellular nicotinamide adenine dinucleotide (NAD+) levels, removal of senescent cells, 'young blood' transfusions, enhancement of adult neurogenesis, stem cell therapy, vascular risk reduction, and non-pharmacological lifestyle strategies. Several studies have shown that these strategies can not only improve brain ageing by attenuating age-related neurodegenerative disease mechanisms, but also maintain cognitive function in a variety of pre-clinical experimental murine models. However, clinical evidence is limited and many of these strategies are awaiting findings from large-scale clinical trials which are nascent in the current literature. Further studies are needed to determine their long-term efficacy and lack of adverse effects in various tissues and organs to gain a greater understanding of their potential beneficial effects on brain ageing and health span in humans.

Long-Term Blood Pressure Variability and Risk of Cognitive Decline and Dementia Among Older Adults

Background

Blood pressure variability (BPV) in midlife increases risk of late‐life dementia, but the impact of BPV on the cognition of adults who have already reached older ages free of major cognitive deficits is unknown. We examined the risk of incident dementia and cognitive decline associated with long‐term, visit‐to‐visit BPV in a post hoc analysis of the ASPREE (Aspirin in Reducing Events in the Elderly) trial.

Methods and Results

ASPREE participants (N=19 114) were free of dementia and significant cognitive impairment at enrollment. Measurement of BP and administration of a standardized cognitive battery evaluating global cognition, delayed episodic memory, verbal fluency, and processing speed and attention occurred at baseline and follow‐up visits. Time‐to‐event analysis using Cox proportional hazards regression models were used to calculate hazard ratios (HR) and corresponding 95% CI for incident dementia and cognitive decline, according to tertile of SD of systolic BPV. Individuals in the highest BPV tertile compared with the lowest had an increased risk of incident dementia and cognitive decline, independent of average BP and use of antihypertensive drugs. There was evidence that sex modified the association with incident dementia (interaction P=0.02), with increased risk in men (HR, 1.68; 95% CI, 1.19–2.39) but not women (HR, 1.01; 95% CI, 0.72–1.42). For cognitive decline, similar increased risks were observed for men and women (interaction P=0.15; men: HR, 1.36; 95% CI, 1.16–1.59; women: HR, 1.14; 95% CI, 0.98–1.32).

Conclusions

High BPV in older adults without major cognitive impairment, particularly men, is associated with increased risks of dementia and cognitive decline.

Registration

URL: https://www.clinicaltrials.gov; Unique identifier: NCT01038583; isrctn.com. Identifier: ISRCTN83772183.

Visit-to-Visit Blood Pressure Variability Is Associated With Cognitive Decline and Incident Dementia: The S.AGES Cohort

To investigate the impact of visit-to-visit systolic blood pressure variability (BPV), diastolic BPV, mean arterial pressure variability, and pulse pressure variability on cognitive decline and incident dementia in noninstitutionalized patients aged ≥65 years. A total of 3319 subjects from the S.AGES (Sujets AGÉS-Aged Subjects) cohort underwent clinical examinations every 6 months during 3 years. Variability was evaluated using standard deviation (SD), coefficient of variation, average real variability, successive variation, variation independent of mean, and residual SD. Cognition was assessed using the Mini-Mental State Examination and dementia with the Diagnostic Statistical Manual of Mental Disorders. Linear mixed models and Cox proportional hazards models were used. Higher systolic BPV was associated with poorer cognition independently of baseline SBP: adjusted 1-SD increase of coefficient of variation: β (SE)=-0.12 (0.06), P=0.04. Similar results were observed for diastolic BPV and mean arterial pressure variability: β (SE)=-0.20 (0.06), P<0.001 for both. Higher pulse pressure variability was no longer associated with cognitive function after adjustment for age, except with residual SD (P=0.02). Among the 3319 subjects, 93 (2.8%) developed dementia. Higher systolic BPV was associated with greater dementia risk (adjusted 1-SD increase of coefficient of variation: hazard ratios=1.23 [95% CI, 1.01-1.50], P=0.04). Similar results were found for diastolic BPV and mean arterial pressure variability (P<0.01). Pulse pressure variability was not associated with dementia risk. Beyond hypertension, higher BPV is a major clinical predictor of cognitive impairment and dementia. Further studies are needed to assess whether controlling BP instability could be a promising interventional target in preserving cognition among older adults.

Antihypertensive medications ameliorate Alzheimer's disease pathology by slowing its propagation

INTRODUCTION

Mounting evidence supports an association between antihypertensive medication use and reduced risk of Alzheimer's disease (AD). Consensus on possible pathological mechanisms remains elusive.

METHODS

Human brain tissue from a cohort followed to autopsy that included 96 cases of AD (46 medicated for hypertension) and 53 pathological controls (33 also medicated) matched for cerebrovascular disease was available from the New South Wales Brain Banks. Quantified frontal cortex amyloid beta (Aβ) and tau proteins plus Alzheimer's neuropathologic change scores were analyzed.

RESULTS

Univariate analyses found no difference in amounts of AD proteins in the frontal cortex between medication users, but multivariate analyses showed that antihypertensive medication use was associated with a less extensive spread of AD proteins throughout the brain.

DISCUSSION

The heterogeneous nature of the antihypertensive medications is consistent with downstream beneficial effects of blood pressure lowering and/or management being associated with the reduced spreading of AD pathology observed.

The psychological consequences of (perceived) ionizing radiation exposure: a review on its role in radiation-induced cognitive dysfunction

PURPOSE

Exposure to ionizing radiation following environmental contamination (e.g., the Chernobyl and Fukushima nuclear accidents), radiotherapy and diagnostics, occupational roles and space travel has been identified as a possible risk-factor for cognitive dysfunction. The deleterious effects of high doses (≥1.0 Gy) on cognitive functioning are fairly well-understood, while the consequences of low (≤0.1 Gy) and moderate doses (0.1-1.0 Gy) have been receiving more research interest over the past decade. In addition to any impact of actual exposure on cognitive functioning, the persistent psychological stress arising from perceived exposure, particularly following nuclear accidents, may itself impact cognitive functioning. In this review we offer a novel interdisciplinary stance on the cognitive impact of radiation exposure, considering psychological and epidemiological observations of different exposure scenarios such as atomic bombings, nuclear accidents, occupational and medical exposures while accounting for differences in dose, rate of exposure and exposure type. The purpose is to address the question that perceived radiation exposure - even where the actual absorbed dose is 0.0 Gy above background dose - can result in psychological stress, which could in turn lead to cognitive dysfunction. In addition, we highlight the interplay between the mechanisms of perceived exposure (i.e., stress) and actual exposure (i.e., radiation-induced cellular damage), in the generation of radiation-induced cognitive dysfunction. In all, we offer a comprehensive and objective review addressing the potential for cognitive defects in the context of low- and moderate-dose IR exposures.

CONCLUSIONS

Overall the evidence shows prenatal exposure to low and moderate doses to be detrimental to brain development and subsequent cognitive functioning, however the evidence for adolescent and adult low- and moderate-dose exposure remains uncertain. The persistent psychological stress following accidental exposure to low-doses in adulthood may pose a greater threat to our cognitive functioning. Indeed, the psychological implications for instructed cohorts (e.g., astronauts and radiotherapy patients) is less clear and warrants further investigation. Nonetheless, the psychosocial consequences of low- and moderate-dose exposure must be carefully considered when evaluating radiation effects on cognitive functioning, and to avoid unnecessary harm when planning public health response strategies.

Blood pressure and cognitive decline - the impact of hypertension over one decade

BACKGROUND

Midlife hypertension is a risk factor for cognitive decline in late-life but little is known about the impact of long-term hypertension on cognitive change over time.

METHODS

We examined blood pressure and cognitive function in 2777 participants (baseline: 2000-2003, 45-75 years, 48.4% men) from the Heinz Nixdorf Recall study. Blood pressure was assessed at three study visits and cognitive function was assessed at both follow-ups (mean follow-up: 5.1 years). Z-score differences in five neuropsychological tests, defining cognitive decline, were derived from linear regression models including age and education. The association of cognitive decline over 5 years and blood pressure over 10 years (classified as: normal blood pressure (>10 years, reference), prevalent hypertension (>10 years), incident hypertension t1 (>5 years), incident hypertension t2 (<5 years), temporary hypertension (at least one hypertensive reading)) was calculated using linear regression models resulting in coefficient b and 95% confidence interval. We calculated interactions with age (linear and with a cutoff at 65 years).

RESULTS

Participants with prevalent hypertension showed a greater cognitive decline in both verbal memory tests. Incident hypertension t1 was associated with a greater decline in the visuospatial organization test. There was no interaction with age.

CONCLUSION

This study showed that prevalent high blood pressure over 10 years is related to cognitive decline. Prevalent hypertension with longer exposure time may be more detrimental than temporary hypertension for cognitive function.

Systolic inter-arm blood pressure difference and risk of cognitive decline in older people: a cohort study

BACKGROUND

Systolic inter-arm difference in blood pressure (IAD) and cognitive decline are both associated with cardiovascular disease; therefore, it was hypothesised that IAD may be predictive of cognitive decline.

AIM

To examine associations of IAD with cognitive decline in a community population.

DESIGN AND SETTING

A prospective study of older Italian adults enrolled in the InCHIANTI study.

METHOD

Univariable and multivariable associations of IAD were explored with declines in mini mental state examination (MMSE) scores, Trail Making Test A and B scores, and a composite outcome representing substantial decline in any of these scores. Backward stepwise regression was used to adjust observed associations of IAD with cognitive decline.

RESULTS

The rate of decline for MMSE scores in 1133 participants was greater with IAD ≥5 mmHg or ≥10 mmHg. On univariable analyses continuous IAD was associated with the composite outcome (odds ratio [OR] 1.16 per 5 mmHg of IAD, 95% confidence interval [CI] = 1.02 to 1.31). Substantial decline in MMSE score was seen with IAD ≥5 mmHg (OR 1.41, 95% CI = 1.03 to 1.93), and in the composite outcome with IAD ≥5 mmHg (OR 1.44, 95% CI = 1.10 to 1.89) or ≥10 mmHg (OR 1.39, 95% CI = 1.03 to 1.88). After multivariable adjustment, an IAD ≥ 5 mmHg remained associated with reductions in the composite outcome, reflecting declining cognitive performance (OR 1.46, 95% CI = 1.05 to 2.03).

CONCLUSION

An IAD ≥5 mmHg is associated with cognitive decline in a representative older population. Given that systolic inter-arm differences in blood pressure are easily measured, confirmation of these findings could inform individualised treatment for the prevention of cognitive decline and dementia.

Non-Amyloid Approaches to Disease Modification for Alzheimer's Disease: An EU/US CTAD Task Force Report

While amyloid-targeting therapies continue to predominate in the Alzheimer’s disease (AD) drug development pipeline, there is increasing recognition that to effectively treat the disease it may be necessary to target other mechanisms and pathways as well. In December 2019, The EU/US CTAD Task Force discussed these alternative approaches to disease modification in AD, focusing on tau-targeting therapies, neurotrophin receptor modulation, anti-microbial strategies, and the innate immune response; as well as vascular approaches, aging, and non-pharmacological approaches such as lifestyle intervention strategies, photobiomodulation and neurostimulation. The Task Force proposed a general strategy to accelerate the development of alternative treatment approaches, which would include increased partnerships and collaborations, improved trial designs, and further exploration of combination therapy strategies.