Sex differences in the association of Framingham Cardiac Risk Score with cognitive decline in community-dwelling elders without clinical heart disease

Role of Cardiovascular Risk in Associations of Brain-Derived Neurotrophic Factor with Longitudinal Brain and Cognitive Trajectories in Older Adults

BACKGROUND

Higher levels of brain-derived neurotrophic factor (BDNF) have been associated with better neurocognitive outcomes. BDNF is present in cardiovascular tissue, and some evidence suggests it may benefit cardiovascular function. The current study assessed whether there is a mediating and/or moderating role of cardiovascular health in the relationship between BDNF and brain and cognitive outcomes.

METHOD

We examined longitudinal data from 397 older adults (aged 54-89;164 females, 233 males) enrolled in the Alzheimer's Disease Neuroimaging Initiative with available plasma BDNF, medical, neuroimaging, and cognitive assessments. We used path analysis and linear regression to estimate the mediating and moderating roles of two measures of cardiovascular health, the Framingham Risk Score (FRS) and pulse pressure, in the relationships between BDNF and longitudinal changes in brain structure (white matter hyperintensity volume, hippocampal volume, and primary visual cortex volume) and cognitive function (executive function, episodic memory, and language).

RESULTS

There was no significant association of plasma BDNF with FRS or pulse pressure (ps > 0.31), precluding mediation. There were no robust associations between BDNF and longitudinal change in any brain structural or cognitive measures (ps > .12). Higher FRS was significantly associated with greater increases in WMH volume (ps < .01). FRS and pulse pressure were not associated with any other brain structural or cognitive outcomes (ps > .07).

CONCLUSION

These results suggest that cardiovascular health may not play an important role in the influence of BDNF on neurocognitive health in older adults.

Predictors of cognitive change in cognitively healthy older women in Panama: the PARI-HD study

Background

Evidence suggests that a combination of biological and social factors influence risk of dementia differently for women and men. In healthy older women, several factors may contribute to changes in cognition.

Objective

Describe the characteristics associated with variation in cognition in a sample of cognitively healthy older Panamanian women.

Methods

The study includes cross-sectional analyses of cognitive domains at baseline (n = 357) and 17-month (SD = 2.0) follow-up (n = 200) for women aged 60 years and older enrolled in the Panama Aging Research Initiative-Health Disparities (PARI-HD) study. Instruments included clinical questionnaires, physiological measures, and a neuropsychological test battery assessing global cognition and seven cognitive domains. Multiple regression analyses examined the associations between demographic and clinical characteristics and cognition at baseline. Repeated measures analyses were used to investigate changes in cognition from baseline to follow-up.

Results

On average, participants were 68.6 years of age (SD = 5.9) with 16.1 years of education (SD = 4.7). Age, income, and education showed robust associations with baseline cognition. Subjective cognitive impairment was associated with lower performance in global cognition, verbal learning, and memory domains. Only performance in the attention domain decreased at follow-up, and subjective health state and depressive symptoms significantly predicted the change in attention.

Discussion

Our study findings contribute to the investigation of cognitive health in older Hispanic women and to the understanding of sociodemographic and health-related factors associated with cognitive decline and the progression to cognitive impairment and dementia.

Sex matters in the association between cardiovascular health and incident dementia: evidence from real world data

BACKGROUND

Cardiovascular health has been associated with dementia onset, but little is known about the variation of such association by sex and age considering dementia subtypes. We assessed the role of sex and age in the association between cardiovascular risk and the onset of all-cause dementia, Alzheimer's disease, and vascular dementia in people aged 50-74 years.

METHODS

This is a retrospective cohort study covering 922.973 Catalans who attended the primary care services of the Catalan Health Institute (Spain). Data were obtained from the System for the Development of Research in Primary Care (SIDIAP database). Exposure was the cardiovascular risk (CVR) at baseline categorized into four levels of Framingham-REGICOR score (FRS): low (FRS < 5%), low-intermediate (5% ≤ FRS < 7.5%), high-intermediate (7.5% ≤ FRS < 10%), high (FRS ≥ 10%), and one group with previous vascular disease. Cases of all-cause dementia and Alzheimer's disease were identified using validated algorithms, and cases of vascular dementia were identified by diagnostic codes. We fitted stratified Cox models using age parametrized as b-Spline.

RESULTS

A total of 51,454 incident cases of all-cause dementia were recorded over a mean follow-up of 12.7 years. The hazard ratios in the low-intermediate and high FRS groups were 1.12 (95% confidence interval: 1.08-1.15) and 1.55 (1.50-1.60) for all-cause dementia; 1.07 (1.03-1.11) and 1.17 (1.11-1.24) for Alzheimer's disease; and 1.34 (1.21-1.50) and 1.90 (1.67-2.16) for vascular dementia. These associations were stronger in women and in midlife compared to later life in all dementia types. Women with a high Framingham-REGICOR score presented a similar risk of developing dementia - of any type - to women who had previous vascular disease, and at age 50-55, they showed three times higher risk of developing dementia risk compared to the lowest Framingham-REGICOR group.

CONCLUSIONS

We found a dose‒response association between the Framingham-REGICOR score and the onset of all dementia types. Poor cardiovascular health in midlife increased the onset of all dementia types later in life, especially in women.

Brief Report: Sex Differences in the Association Between Cerebrovascular Function and Cognitive Health in People Living With HIV in Urban China

BACKGROUND

Cardiometabolic and cerebrovascular disease are strong independent contributors to cognitive impairment in people living with HIV. Data suggest that cardiovascular risk may play a greater role in cognitive health in women than in men with HIV.

METHODS

We performed a cross-sectional study of 104 participants with virologically suppressed HIV from 2 clinics in urban China. Participants underwent neuropsychological testing from which we calculated T scores globally and in 5 cognitive domains. We assessed cerebral vasoreactivity of the middle cerebral arteries in response to breath holding. We constructed linear regression models to determine associations between cerebrovascular and cognitive function overall and stratified by sex.

RESULTS

Women were younger than men (48 versus 51 years, P = 0.053), had fewer years of education (9 years versus 12 years, P = 0.004), and fewer cardiometabolic risk factors (0 versus 1 factor, P = 0.008). In a model with all participants, cerebrovascular function was significantly associated with global cognition (2.74 higher T score per 1-point higher cerebral vasoreactivity [SE 1.30], P = 0.037). Cerebrovascular function remained significantly associated with global cognition among women (4.15 higher T score [SE 1.78], P = 0.028) but not men (1.70 higher T score [SE 1.74], P = 0.33). The relationships between cerebrovascular function and specific cognitive domains followed a similar pattern, with significant associations present among women but not men.

CONCLUSIONS

Women with well-controlled HIV may be more vulnerable to the effect of cerebrovascular injury on cognitive health than men. Studies evaluating strategies to protect against cognitive impairment in people living with HIV should include adequate representation of women and stratification of analyses by sex.

Associations Between Korean Coronary Heart Disease Risk Score and Cognitive Function in Dementia-Free Korean Older Adults

BACKGROUND

Cardiovascular risk is a modifiable factor that can help prevent dementia. Given the dearth of optimal treatment options, managing dementia risk factors is crucial. We examined the association between cardiovascular risk, as measured by the Korean coronary heart disease risk score (KRS), and cognitive function in dementia-free elderly individuals.

METHODS

We enrolled 8,600 individuals (average age: 69.74 years; 5,206 women) who underwent a medical evaluation from the National Health Insurance Service. KRS was calculated using age, sex, blood pressure, lipid profile, diabetes, and smoking status. Cognitive function was evaluated using Korean Dementia Screening Questionnaire-Cognition (KDSQ-C). Scores of ≥ 6 indicated a cognitive decline. Logistic regression analysis was used to estimate the odds ratio (OR) and 95% confidence interval (CI). Weight, height, stroke history, coronary heart disease history, alcohol consumption, and physical activity engagement were adjusted.

RESULTS

The lowest, middle, and highest groups, according to the KRS, were 5,923 (68.9%), 2,343 (27.2%), and 334 (3.9%), respectively. The highest KRS group in all participants exhibited a greater risk of cognitive decline than the lowest KRS group (OR, 1.339; 95% CI, 1.034-1.734; P = 0.027). The highest KRS female group aged 71-75 years old exhibited greater cognitive decline than the corresponding lowest KRS group (OR, 1.595; 95% CI, 1.045-2.434; P = 0.031).

CONCLUSION

Individuals with high cardiovascular risk were associated with poorer cognitive function than those with low risk, especially older women. Cardiovascular risk factors should be carefully managed to promote healthy mental aging in dementia-free elderly individuals.

Sex-specific effects of microglial activation on Alzheimer's disease proteinopathy in older adults

Females show a disproportionate burden of Alzheimer's disease pathology and higher Alzheimer's disease dementia prevalences compared to males, yet the mechanisms driving these vulnerabilities are unknown. There is sexual dimorphism in immunological functioning, and neuroimmune processes are implicated in Alzheimer's disease genesis. Using neuropathology indicators from human brain tissue, we examined the mediational role of microglial activation on the relationship between amyloid and tau and how it differs by sex. 187 decedents (64% female; 89 mean age at death; 62% non-demented) from the Rush Memory and Aging Project completed neuropathological evaluations with brain tissue quantified for microglial activation, amyloid-β and tau. Proportion of morphologically activated microglia was determined via immunohistochemistry (HLA-DP-DQ-DR) and morphological staging (stage I, II or III). Amyloid-β and tau burden were quantified via immunohistochemistry (M00872 or AT8, respectively). Using causal counterfactual modelling, we estimated the mediational effect of microglial activation on the amyloid-β to tau relationship in the whole sample and stratified by sex (amyloid-β → microglial activation → tau). Alternative models tested the role of microglia activation as the precipitating event (microglial activation → amyloid-β → tau). Microglial activation significantly mediated 33% [95% confidence interval (CI) 10-67] of the relationship between amyloid-β and tau in the whole sample; stratified analyses suggested this effect was stronger and only statistically significant in females. 57% (95% CI 22-100) of the effect of amyloid-β on tau was mediated through microglial activation in females, compared to 19% (95% CI 0-64) in males. Regional analyses suggested that mediational effects were driven by greater cortical versus subcortical microglial activation. Relationships were independent of cerebrovascular disease indices. Alternative models suggested that in females, microglial activation was a significant exposure both preceding the amyloid-β to tau relationship (mediational effect: 50%, 95% CI 23-90) and directly related to tau burden (microglia direct effect: 50%, 95% CI 10-77). By contrast, in males, only the direct effect of microglial activation to tau reached significance (74%, 95% CI 32-100) (mediational effect: 26%, 95% CI 0-68). Our models suggest a reciprocal, bidirectional relationship between amyloid-β and microglial activation that significantly accounts for tau burden in females. By contrast, in males, direct independent (non-mediational) relationships between microglial activation or amyloid-β with tau were observed. Microglial activation may be disproportionately important for Alzheimer's disease pathogenesis in females. Determining sex-specific vulnerabilities to Alzheimer's disease development both inform fundamental pathophysiology and support precision health approaches for this heterogeneous disease.

Sex and APOE ε4 modify the effect of cardiovascular risk on tau in cognitively normal older adults

The interaction between APOE ε4 and vascular risk factors on cognitive function is stronger in women than in men. These effects may be mediated by the amount of tau pathology in the brain. Therefore, we examined whether APOE ε4 and sex modify cross-sectional associations between cardiovascular risk and tau deposition in cognitively normal older adults from the Alzheimer’s Disease Neuroimaging Initiative. We calculated the Framingham Heart Study cardiovascular disease risk score for 141 participants (74 women, 47 APOE ε4 carriers) with complete medical history data, processed tau PET data and a Clinical Dementia Rating global score of 0.0 at the time of the tau PET scan, implying no significant cognitive or functional impairment. We used linear regression models to examine the effects of sex, APOE ε4, cardiovascular risk and their interactions on tau deposition in the entorhinal cortex, inferior temporal cortex and a composite meta-region of interest of temporal lobe areas. We found a significant three-way interaction among sex, APOE ε4 status, and cardiovascular disease risk on tau deposition in the entorhinal cortex (β = 0.04; 95% CI, 0.01 to 0.07; P =0.008), inferior temporal cortex (β = 0.02; 95% CI, 0.0 to 0.05; P =0.029) and meta-region (β = 0.02; 95% CI, 0.0–0.04; P = 0.042). After stratifying by APOE ε4 status to examine interactions between sex and cardiovascular disease risk on tau in APOE ε4 carriers and non-carriers, we found a significant two-way interaction between sex and cardiovascular disease risk on tau in the entorhinal cortex (β = 0.05; 95% CI, 0.02 to 0.08; P =0.001), inferior temporal cortex (β = 0.03; 95% CI, 0.01 to 0.05; P =0.009) and meta-region (β = 0.02; 95% CI, 0.01 to 0.04; P =0.008) only among APOE ε4 carriers. In analyses stratified by sex, higher cardiovascular risk scores were associated with higher levels of tau in the entorhinal cortex (β = 0.05; 95% CI, 0.02 to 0.08; P =0.002), inferior temporal cortex (β = 0.02; 95% CI, 0.0 to 0.05; P =0.023) and meta-region (β = 0.02; 95% CI, 0.01 to 0.04; P =0.013) in female APOE ε4 carriers but not in male carriers. Our findings suggest that cognitively normal older women carrying at least one APOE ε4 allele, may be particularly vulnerable to the effects of cardiovascular disease risk on early tau deposition.

The association between cardiovascular risk burden and cognitive function amongst the old: a 9-year longitudinal cohort study

BACKGROUND AND PURPOSE

Cardiovascular risk burden in midlife has been linked to cognitive decline in later life, but whether this association still exists in older cohorts is unclear.

METHODS

The association between the cardiovascular risk score and cognitive function was investigated using 9-year follow-up data. The risk score algorithms were from the Chinese guidelines on the prevention and treatment of dyslipidemia in adults (2016 revised), which were assessed at baseline and categorized into tertiles (low, middle and high). Full intelligence quotient (FIQ), verbal intelligence quotient (VIQ) and performance intelligence quotient (PIQ) were assessed at follow-ups with the Wechsler Adult Intelligence Scale-Chinese, revised (WAIS-RC). Data were analyzed using the linear mixed-effects model.

RESULTS

A total of 924 participants (mean age 78.06 ± 7.58 years) were included in our study. In all participants, the risk score ranged from 0.02 to 0.55 (mean score 0.16 ± 0.08). Compared with the low tertile, a higher risk score was associated with lower FIQ (β -0.094, 95% confidence interval [CI] -0.181, -0.007) and VIQ (β -0.100; 95% CI -0.192, -0.007) at the follow-up. There is a more significant association between higher risk score and lower FIQ amongst females (β -0.263; 95% CI -0.462, -0.065) and VIQ (β -0.268; 95% CI -0.478, -0.057).

CONCLUSIONS

A higher cardiovascular risk score was associated with lower FIQ and VIQ. Higher cardiovascular risk burden increased the risk of cognition impairment and accelerated its progression over time. This study has implications for early detection of cognition impairment.

Smoking is associated with impaired verbal learning and memory performance in women more than men

Vascular contributions to cognitive impairment and dementia (VCID) include structural and functional blood vessel injuries linked to poor neurocognitive outcomes. Smoking might indirectly increase the likelihood of cognitive impairment by exacerbating vascular disease risks. Sex disparities in VCID have been reported, however, few studies have assessed the sex-specific relationships between smoking and memory performance and with contradictory results. We investigated the associations between sex, smoking, and cardiovascular disease with verbal learning and memory function. Using MindCrowd, an observational web-based cohort of ~ 70,000 people aged 18-85, we investigated whether sex modifies the relationship between smoking and cardiovascular disease with verbal memory performance. We found significant interactions in that smoking is associated with verbal learning performance more in women and cardiovascular disease more in men across a wide age range. These results suggest that smoking and cardiovascular disease may impact verbal learning and memory throughout adulthood differently for men and women.

Baseline 10-Year Cardiovascular Risk Scores Predict Cognitive Function in Older Persons, and Particularly Women, Living With Human Immunodeficiency Virus Infection

BACKGROUND

Cardiovascular disease (CVD) and associated comorbidities increase the risk of cognitive impairment in persons living with human immunodeficiency virus (PLWH). Given the potential composite effect of multiple cardiovascular risk factors on cognition, we examined the ability of the Atherosclerotic Cardiovascular Disease (ASCVD) risk score and the Framingham Heart Study Global CVD risk score (FRS) to predict future cognitive function in older PLWH.

METHODS

We constructed linear regression models evaluating the association between baseline 10-year cardiovascular risk scores and cognitive function (measured by a summary z-score, the NPZ-4) at a year 4 follow-up visit.

RESULTS

Among 988 participants (mean age, 52 years; 20% women), mean 10-year ASCVD risk score at entry into the cohort was 6.8% (standard deviation [SD], 7.1%) and FRS was 13.1% (SD, 10.7%). In models adjusted only for cognitive function at entry, the ASCVD risk score significantly predicted year 4 NPZ-4 in the entire cohort and after stratification by sex (for every 1% higher ASCVD risk, year 4 NPZ-4 was lower by 0.84 [SD, 0.28] overall, P = .003; lower by 2.17 [SD, 0.67] in women, P = .001; lower by 0.78 [SD, 0.32] in men, P = .016). A similar relationship was observed between FRS and year 4 NPZ-4. In multivariable models, higher 10-year ASCVD risk and FRS predicted lower NPZ-4 in women.

CONCLUSIONS

Baseline 10-year ASCVD risk and FRS predicted future cognitive function in older PLWH with well-controlled infection. Cardiovascular risk scores may help to identify PLWH, especially women, who are at risk for worse cognition over time.

Classic and Novel Sex Hormone Binding Globulin Effects on the Cardiovascular System in Men

In men, 70% of circulating testosterone binds with high affinity to plasma sex hormone binding globulin (SHBG), which determines its bioavailability in their target cells. In recent years, a growing body of evidence has shown that circulating SHBG not only is a passive carrier for steroid hormones but also actively regulates testosterone signaling through putative plasma membrane receptors and by local expression of androgen-binding proteins apparently to reach local elevated testosterone concentrations in specific androgen target tissues. Circulating SHBG levels are influenced by metabolic and hormonal factors, and they are reduced in obesity and insulin resistance, suggesting that SHBG may have a broader clinical utility in assessing the risk for cardiovascular diseases. Importantly, plasma SHBG levels are strongly correlated with testosterone concentrations, and in men, low testosterone levels are associated with an adverse cardiometabolic profile. Although obesity and insulin resistance are associated with an increased incidence of cardiovascular disease, whether they lead to abnormal expression of circulating SHBG or its interaction with androgen signaling remains to be elucidated. SHBG is produced mainly in the liver, but it can also be expressed in several tissues including the brain, fat tissue, and myocardium. Expression of SHBG is controlled by peroxisome proliferator-activated receptor γ (PPARγ) and AMP-activated protein kinase (AMPK). AMPK/PPAR interaction is critical to regulate hepatocyte nuclear factor-4 (HNF4), a prerequisite for SHBG upregulation. In cardiomyocytes, testosterone activates AMPK and PPARs. Therefore, the description of local expression of cardiac SHBG and its circulating levels may shed new light to explain physiological and adverse cardiometabolic roles of androgens in different tissues. According to emerging clinical evidence, here, we will discuss the potential mechanisms with cardioprotective effects and SHBG levels to be used as an early metabolic and cardiovascular biomarker in men.

Sex-specific associations between lipids and cognitive decline in the middle-aged and elderly: a cohort study of Chinese adults

Background

Studies regarding the lipid-cognition relationship have increasingly gained popularity but have generated much mixed results. To date, few studies have focused on the difference between sexes.

Methods

This study included 6792 Chinese adults aged over 45 years (women, 48.56%; mean age, 57.28 years), who were free of severe conditions known to affect cognitive function at the baseline (2011). Blood concentrations of total cholesterol (TC), high-density lipoprotein cholesterol (HDL-c), low-density lipoprotein cholesterol (LDL-c), and triglycerides (TG) were assessed at baseline, and both continuous and categorical values were used in final analyses. Global cognitive functions were assessed by the word recall test and the mental status test in 2011, 2013, and 2015, respectively. We graded participants into three groups according to the cognitive change slopes: no decline (≥ 0), moderate decline (median to 0), and severe decline (< median). Sex-specific associations between blood lipids and cognitive decline were analyzed using ordinal logistic models, adjusting for sociodemographic information, lifestyle behaviors, and health status.

Results

Higher baseline TC and LDL-C concentrations exhibited no significant association with 5-year cognitive decline in men but were significantly associated with greater 5-year cognitive decline in women [odds ratio (OR) 1.026, 95% confidence interval (CI) 1.003, 1.050; OR 1.026, CI 1.002, 1.051, respectively]. For higher serum HDL-c levels, a significantly protective effect on cognition was observed in men, but a slightly adverse effect was found in women (not significant after Bonferroni correction). TG presented almost no effect on later cognition in either sex.

Conclusion

Different associations between sexes were observed for the lipid-cognition relationship, and maintaining serum cholesterol levels at an appropriate range may have a positive effect on cognitive health.

Associations Between Cardiovascular Risk, Structural Brain Changes, and Cognitive Decline

BACKGROUND

The impact of cardiovascular risk burden on cognitive trajectories and brain structure changes remains unclear.

OBJECTIVES

This study aimed to examine whether cardiovascular risk burden assessed by the Framingham General Cardiovascular Risk Score (FGCRS) is associated with cognitive decline and structural brain differences.

METHODS

Within the Rush Memory and Aging Project, 1,588 dementia-free participants (mean age: 79.5 years) were followed for up to 21 years. FGCRS was assessed at baseline and categorized into tertiles (lowest, middle, and highest). Episodic memory, semantic memory, working memory, visuospatial ability, and perceptual speed were assessed annually with a battery of 19 tests, from which composite scores were derived. A subsample (n = 378) of participants underwent magnetic resonance imaging. Structural total and regional brain volumes were estimated. Data were analyzed using linear mixed-effects models and linear regression models.

RESULTS

In all participants, FGCRS ranged from 4 to 28 (mean score: 15.6 ± 3.7). Compared with the lowest tertile of FGCRS, the highest tertile was associated with faster decline in global cognition (β = -0.019; 95% confidence interval [CI]: -0.035 to -0.003), episodic memory (β = -0.023; 95% CI: -0.041 to -0.004), working memory (β = -0.021; 95% CI: -0.035 to -0.007), and perceptual speed (β = -0.027; 95% CI: -0.042 to -0.011) over the follow-up. In magnetic resonance imaging data analyses, higher FGCRS was related to smaller volumes of the hippocampus (β = -0.021; 95% CI: -0.042 to -0.000), gray matter (β = -1.569; 95% CI: -2.757 to -0.382), and total brain (β = -1.588; 95% CI: -2.832 to -0.344), and greater volume of white matter hyperintensities (β = 0.035; 95% CI: 0.001 to 0.069).

CONCLUSIONS

Higher cardiovascular risk burden may predict decline in episodic memory, working memory, and perceptual speed and is associated with neurodegeneration and vascular lesions in the brain.

Associations Between Midlife (but Not Late-Life) Elevated Coronary Heart Disease Risk and Lower Cognitive Performance: Results From the Framingham Offspring Study

It is unclear how coronary heart disease (CHD) risk across the adult life span affects late-life cognition. We estimated associations of midlife and late-life elevated CHD risk with cognitive trajectories (general cognitive performance, processing speed/executive function, memory) in later life (after age 55 years or age 70 years) among 2,892 Framingham Offspring Study participants who had completed CHD risk assessments approximately every 4 years since 1971 and had undergone neuropsychological testing between 1999 and 2014. We stratified analyses by apolipoprotein E gene (APOE) Ɛ4 allele carrier status. Using linear mixed-effects models, elevated CHD risk in midlife (age 55 years) was associated with lower levels of general cognitive performance (β = -0.560 standard deviation (SD) units, 95% confidence interval (CI): -0.874, -0.246), executive function (β = -0.624 SD units, 95% CI: -0.916, -0.332), and memory (β = -0.560 SD units, 95% CI: -0.907, -0.213) at age 70 years but not with rates of cognitive change. Late-life (age 70 years) elevated CHD risk, however, was associated with somewhat better levels of general cognitive performance and memory. There were associations between duration of elevated CHD risk during midlife and levels (but not trajectories) of later-life cognitive outcomes. Associations were not modified by APOE-ɛ4 status. These findings suggest that midlife elevated CHD risk is associated with lower cognition, independently of APOE-ɛ4 status, suggesting that risk of vascular disease may not contribute a "second hit" to AD risk.

Physical Activity Is Associated With Lower Odds of Cognitive Impairment in Women but Not Men Living With Human Immunodeficiency Virus Infection

Background

Cardiovascular comorbidities are risk factors for human immunodeficiency virus (HIV)-associated cognitive impairment. Given differences in cardiometabolic risk profiles between women and men with HIV, we investigated whether associations between cardiometabolic risk factors and prevalent cognitive impairment differ by sex.

Methods

Separate logistic regression models were constructed for women and men at entry into a prospective study of older persons with HIV (PWH) to assess the association of cardiometabolic and other risk factors with cognitive impairment.

Results

Of 988 participants, 20% were women. Women had higher total cholesterol (194 vs 186 mg/dL; P = .027), hemoglobin A1c (5.9% vs 5.7%; P = .003), and body mass index (30.8 vs 27.4 kg/m2; P < .001) compared with men, and were less physically active (43% vs 55%; P = .005). In a multivariable model, physical activity was associated with lower odds of cognitive impairment in women (odds ratio, 0.35 [95% confidence interval, .15-.80]; P = .013) but not men.

Conclusions

Physical activity may have a greater positive impact on cognitive health in women than in men with HIV. This finding should be confirmed in studies examining the longitudinal association between physical activity and incident cognitive impairment in PWH and the effect of interventions that increase physical activity on cognitive impairment in women with HIV.

Cognitive Associates of Current and More Intensive Control of Hypertension: Findings From the Hispanic Community Health Study/Study of Latinos

BACKGROUND

Hypertension control in Hispanics/Latinos lag behind general US trends by 10-15%. Intensive systolic blood pressure (SBP) management <120 mm Hg may significantly reduce morbidity/mortality risk in adults with hypertension; less is known about cognition. We investigated cross-sectional associations of cognition with observed hypertension control at currently recommended (SBP < 140 mm Hg) and more intensive (SBP < 120 mm Hg) levels using baseline data from the Hispanic Community Health Study/Study of Latinos.

METHODS

From this multicenter cohort study, we focused on 1,735 Hispanic/Latino men and women ages 45-74 years with hypertension and verified antihypertensive use. Verbal fluency, information processing speed, learning, and memory were tested in Spanish or English.

RESULTS

Separate linear regressions revealed that being on 1 vs. >1 antihypertensive medication was not associated with cognition; however, individuals with SBP controlled to currently recommended levels outperformed individuals with uncontrolled SBP on verbal fluency [Beta = 1.44 (0.52), P < 0.01] and information processing speed [Beta = 3.01 (0.89), P < 0.001] in age-adjusted regression analyses; only information processing speed remained significant (P < 0.05) after additional adjustments including acculturation, health insurance, and other cardiovascular disease risk factors. When regrouping individuals based on more intensive SBP control, individuals with levels <120 mm Hg outperformed individuals with higher SBP on verbal fluency regardless of adjustments (P < 0.01). More intensive rather than currently recommended levels of control associated with higher verbal fluency performance regardless of adjustments (P < 0.05).

CONCLUSIONS

Individual cognitive test scores related to distinct SBP management with more intensive management appearing more robust against confounders. While cognitive associations with hypertension in Hispanics/Latinos may be multifactorial, different levels of SBP control should be considered in future prospective intervention studies.

Pathophysiologic relationship between Alzheimer's disease, cerebrovascular disease, and cardiovascular risk: A review and synthesis

As the population ages due to demographic trends and gains in life expectancy, the incidence and prevalence of dementia increases, and the need to understand the etiology and pathogenesis of dementia becomes ever more urgent. Alzheimer's disease (AD), the most common form of dementia, is a complex disease, the mechanisms of which are poorly understood. The more we learn about AD, the more questions are raised about our current conceptual models of disease. In the absence of a cure or the means by which to slow disease progress, it may be prudent to apply our current knowledge of the intersection between AD, cardiovascular disease, and cerebrovascular disease to foster efforts to delay or slow the onset of AD. This review discusses our current understanding of the epidemiology, genetics, and pathophysiology of AD, the intersection between AD and vascular causes of dementia, and proposes future directions for research and prevention.

Predicting Risk of Cognitive Decline in Very Old Adults Using Three Models: The Framingham Stroke Risk Profile; the Cardiovascular Risk Factors, Aging, and Dementia Model; and Oxi-Inflammatory Biomarkers

OBJECTIVES

To examine the Framingham Stroke Risk Profile (FSRP); the Cardiovascular Risk Factors, Aging, and Incidence of Dementia (CAIDE) risk score, and oxi-inflammatory load (cumulative risk score of three blood biomarkers-homocysteine, interleukin-6, C-reactive protein) for associations with cognitive decline using three cohort studies of very old adults and to examine whether incorporating these biomarkers with the risk scores can affect the association with cognitive decline.

DESIGN

Three longitudinal, population-based cohort studies.

SETTING

Newcastle-upon-Tyne, United Kingdom; Leiden, the Netherlands; and Lakes and Bay of Plenty District Health Board areas, New Zealand.

PARTICIPANTS

Newcastle 85+ Study participants (n = 616), Leiden 85-plus Study participants (n = 444), and Life and Living in Advanced Age, a Cohort Study in New Zealand (LiLACS NZ Study) participants (n = 396).

MEASUREMENTS

FSRP, CAIDE risk score, oxi-inflammatory load, FSRP incorporating oxi-inflammatory load, and CAIDE risk score incorporating oxi-inflammatory load. Oxi-inflammatory load could be calculated only in the Newcastle 85+ and the Leiden 85-plus studies. Measures of global cognitive function were available for all three data sets. Domain-specific measures were available for the Newcastle 85+ and the Leiden 85-plus studies.

RESULTS

Meta-analysis of pooled results showed greater risk of incident global cognitive impairment with higher FSRP (hazard ratio (HR) = 1.46, 95% confidence interval (CI) = 1.08-1.98), CAIDE (HR = 1.53, 95% CI = 1.09-2.14), and oxi-inflammatory load (HR = 1.73, 95% CI = 1.04-2.88) scores. Adding oxi-inflammatory load to the risk scores increased the risk of cognitive impairment for the FSRP (HR = 1.65, 95% CI = 1.17-2.33) and the CAIDE model (HR = 1.93, 95% CI = 1.39-2.67).

CONCLUSION

Adding oxi-inflammatory load to cardiovascular risk scores may be useful for determining risk of cognitive impairment in very old adults.

Cognitive Impairment Among the Aging Population in a Community in Southwest Nigeria

Background. Vascular risk models can be quite informative in assisting the clinician to make a prediction of an individual’s risk of cognitive impairment. Thus, a simple marker is a priority for low-capacity settings. This study examines the association of selected simple to deploy vascular markers with cognitive impairment in an elderly population. Method. This cross-sectional study assessed the cognitive functions of older persons 65 years and older in southwest Nigeria. Vascular parameters and risk factors were also measured. Analysis was done using SPSS, and logistic regression was used to explore the association between cognitive impairment and certain vascular risk factors such as elevated blood pressure, diabetes, and pulse pressure. Results. The study population comprised 623 participants (29.1% men) with mean age 73 ± 8.9 years. Having mean arterial pressure (MAP) and pulse pressure in the fourth quartiles (27% and 29.9%, respectively) was significantly associated with cognitive impairment ( p = .001, p < .001). Predicted cardiovascular risks of 10% or more was significantly associated with cognitive impairment ( p < .001). After adjusting for age, gender, educational level, and years of smoking, those with MAP in the fourth quartile were up to 3 times more likely to have cognitive impairment compared to those within the first quartile. Conclusion. Our study demonstrated that among elderly Nigerians, MAPs of 114 mmHg and more was an independent predictor of cognitive impairment. This is a simple measure that is available in low-capacity areas.

Insulin resistance is associated with poorer verbal fluency performance in women

AIMS/HYPOTHESIS

Type 2 diabetes is an independent risk factor for cognitive decline. Insulin resistance occurring during midlife may increase the risk of cognitive decline later in life. We hypothesised that insulin resistance is associated with poorer cognitive performance and that sex and APOE*E4 might modulate this association.

METHODS

The association of insulin resistance and APOE*E4 genotype on cognitive function was evaluated in a nationwide Finnish population-based study (n = 5,935, mean age 52.5 years, range 30-97 years). HOMA-IR was used to measure insulin resistance. Cognitive function was tested by word-list learning, word-list delayed-recall, categorical verbal fluency and simple and visual-choice reaction-time tests. Linear regression analysis was used to determine the association between HOMA-IR and the results of the cognitive tests.

RESULTS

Higher HOMA-IR was associated with poorer verbal fluency in women (p < 0.0001) but not in men (p = 0.56). Higher HOMA-IR was also associated with poorer verbal fluency in APOE*E4 -negative individuals (p = 0.0003), but not in APOE*E4 carriers (p = 0.28). Furthermore, higher HOMA-IR was associated with a slower simple reaction time in the whole study group (p = 0.02).

CONCLUSIONS/INTERPRETATION

To our knowledge, this is the first comprehensive, population-based study, including both young and middle-aged adults, to report that female sex impacts the association of HOMA-IR with verbal fluency. Our study was cross-sectional, so causal effects of HOMA-IR on cognition could not be evaluated. However, our results suggest that HOMA-IR could be an early marker for an increased risk of cognitive decline in women.

Are different vascular risk scores calculated at midlife uniformly associated with subsequent poor cognitive performance?

BACKGROUND

Research concerning the link between individual vascular risk factors and cognition is plentiful but few studies have investigated the role of global vascular risk. We examined the cross-time associations of several vascular risk scores with cognitive performance during aging.

METHODS

Using data from the French SU.VI.MAX cohort, we studied a sample of 3061 participants. Framingham coronary heart disease, cardiovascular and stroke risk profiles were computed using baseline data (1994-1996). Cognitive performance was assessed after a mean of 13 years via a battery of six validated instruments. Principal component analysis identified scores for verbal memory and working memory. Associations between risk profiles (as continuous variables and in quartiles (Q)) and subsequent poor performance (defined as cognitive score ≤10th percentile) were examined via logistic regression (odds ratios, 95% CI) and analysis of covariance.

RESULTS

All continuous-scale Framingham risk scores assessed at midlife were inversely and uniformly associated with subsequent poor global cognitive performance, and especially in terms of verbal memory. Considering risk score Q, higher Q were associated with poorer performance in verbal memory: The fully-adjusted odds ratios (95% CI), comparing Q4 versus Q1, were 2.84 (1.70, 4.75), 2.31 (1.43, 3.73) and 1.77 (1.13, 2.76) for Framingham coronary heart disease, cardiovascular and stroke risk profiles, respectively. Similar findings were observed when modeling cognitive outcomes as continuous variables using covariance analyses.

CONCLUSION

This study supports the existence of an inverse cross-time association between midlife vascular risk profiles and subsequent poor cognitive performance, especially in the verbal memory domain. Beyond their importance as regards vascular risk, such risk scores may help primary prevention efforts in identifying and targeting middle-aged individuals at high risk of cognitive aging.

Plasma leptin levels are not predictive of dementia in patients with mild cognitive impairment

BACKGROUND

animal studies suggest a neuroprotective role for leptin, but human studies have shown mixed results. We examined whether plasma leptin levels in individuals with mild cognitive impairment (MCI) were related to cognitive function at baseline and whether higher leptin levels were associated with reduced risk of dementia.

METHODS

we categorised 352 MCI participants into sex-specific tertiles based on log-transformed fasting plasma leptin levels. In sex-stratified analyses, we investigated whether cognitive ability differed by leptin tertile. We also examined whether the risk of dementia over a 3-year follow-up period differed by leptin level. Analyses controlled for numerous potential confounding variables, including body mass index, hypertension and levels of blood insulin and C-reactive protein.

RESULTS

baseline cognitive ability did not differ as a function of leptin level, nor were higher leptin levels associated with reduced hazard of developing dementia. Controlling for related co-variates did not reveal any significant associations between leptin and dementia risk.

CONCLUSION

in this cohort of older adults with MCI, plasma leptin level was not associated with cognitive function at baseline, nor did it predict risk of dementia. Other biological measures, such as volumetric MRI and cerebrospinal fluid protein levels, have demonstrated robust dementia prediction in this cohort. Thus, the current negative findings suggest that plasma leptin, on its own, is unlikely to become a useful clinical biomarker for Alzheimer's disease. Efforts to develop other blood-based biomarkers are needed.

Cardiovascular disease risk models and longitudinal changes in cognition: a systematic review

Background

Cardiovascular disease and its risk factors have consistently been associated with poor cognitive function and incident dementia. Whether cardiovascular disease prediction models, developed to predict an individual's risk of future cardiovascular disease or stroke, are also informative for predicting risk of cognitive decline and dementia is not known.

Objective

The objective of this systematic review was to compare cohort studies examining the association between cardiovascular disease risk models and longitudinal changes in cognitive function or risk of incident cognitive impairment or dementia.

Materials and Methods

Medline, PsychINFO, and Embase were searched from inception to March 28, 2014. From 3,413 records initially screened, 21 were included.

Results

The association between numerous different cardiovascular disease risk models and cognitive outcomes has been tested, including Framingham and non-Framingham risk models. Five studies examined dementia as an outcome; fourteen studies examined cognitive decline or incident cognitive impairment as an outcome; and two studies examined both dementia and cognitive changes as outcomes. In all studies, higher cardiovascular disease risk scores were associated with cognitive changes or risk of dementia. Only four studies reported model prognostic performance indices, such as Area Under the Curve (AUC), for predicting incident dementia or cognitive impairment and these studies all examined non-Framingham Risk models (AUC range: 0.74 to 0.78).

Conclusions

Cardiovascular risk prediction models are associated with cognitive changes over time and risk of dementia. Such models are easily obtainable in clinical and research settings and may be useful for identifying individuals at high risk of future cognitive decline and dementia.

Association of vascular risk factors with cognition in a multiethnic sample

OBJECTIVES

To examine the relationship between cardiovascular risk factors (CVRFs) and cognitive performance in a multiethnic sample of older adults.

METHOD

We used longitudinal data from the Washington Heights-Inwood Columbia Aging Project. A composite score including smoking, stroke, heart disease, diabetes, hypertension, and central obesity represented CVRFs. Multiple group parallel process multivariate random effects regression models were used to model cognitive functioning and examine the contribution of CVRFs to baseline performance and change in general cognitive processing, memory, and executive functioning.

RESULTS

Presence of each CVRF was associated with a 0.1 SD lower score in general cognitive processing, memory, and executive functioning in black and Hispanic participants relative to whites. Baseline CVRFs were associated with poorer baseline cognitive performances among black women and Hispanic men. CVRF increase was related to baseline cognitive performance only among Hispanics. CVRFs were not related to cognitive decline. After adjustment for medications, CVRFs were not associated with cognition in Hispanic participants.

DISCUSSION

CVRFs are associated with poorer cognitive functioning, but not cognitive decline, among minority older adults. These relationships vary by gender and medication use. Consideration of unique racial, ethnic, and cultural factors is needed when examining relationships between CVRFs and cognition.

Heart disease as a risk factor for dementia

As life expectancy lengthens, dementia is becoming a significant human condition in terms of its prevalence and cost to society worldwide. It is important in that context to understand the preventable and treatable causes of dementia. This article exposes the link between dementia and heart disease in all its forms, including coronary artery disease, myocardial infarction, atrial fibrillation, valvular disease, and heart failure. This article also explores the cardiovascular risk factors and emphasizes that several of them are preventable and treatable. In addition to medical therapies, the lifestyle changes that may be useful in retarding the onset of dementia are also summarized.

Cardiovascular risk score, cognitive decline, and dementia in older Mexican Americans: the role of sex and education

Background

The purpose of this study was to examine the associations of cardiovascular disease (CVD) risk with cognitive decline and incidence of dementia and cognitive impairment but not dementia (CIND) and the role of education as a modifier of these effects.

Methods and Results

One thousand one hundred sixteen Mexican American elderly were followed annually in the Sacramento Area Latino Study on Aging. Our sex‐specific 10‐year CVD risk score included baseline age, systolic blood pressure, total cholesterol, high‐density lipoprotein, smoking, body mass index, and diabetes. From adjusted linear mixed models, errors on the Modified Mini–Mental State Exam (3MSE) were annually 0.41% lower for women at the 25th percentile of CVD risk, 0.11% higher at the 50th percentile, and 0.83% higher at the 75th percentile (P value of CVDrisk×time <0.01). In men, 3MSE errors were annually 1.76% lower at the 25th percentile of CVD risk, 0.96% lower at the 50th percentile, and 0.12% higher at the 75th percentile (P value of CVDrisk×time <0.01). From adjusted linear mixed models, the annual decrease in the Spanish and English Verbal Learning Test score was 0.09 points for women at the 25th percentile of CVD risk, 0.10 points at the 50th percentile, and 0.12 points at the 75th percentile (P value of CVDrisk×time=0.02). From adjusted Cox models in women, compared with having <6 years of education, having 12+ years of education was associated with a 76% lower hazard of dementia/CIND (95% CI, 0.08 to 0.71) at the 25th percentile of CVD risk and with a 45% lower hazard (95% CI, 0.28 to 1.07) at the 75th percentile (P value of CVDrisk×education=0.05).

Conclusions

CVD risk score may provide a useful tool for identifying individuals at risk for cognitive decline and dementia.

Sex differences in cardiac autonomic regulation and in repolarisation electrocardiography

The review summarises the present knowledge on the sex differences in cardiac autonomic regulations and in related aspects of electrocardiography with particular attention to myocardial repolarisation. Although some of the sex differences are far from fully established, multitude of observations show consistent differences between women and men. Despite more pronounced parasympathetic cardiac regulation, women have higher resting heart rate and lower baroreflex sensitivity. Of the electrocardiographic phenomena, women have longer QT interval duration, repolarisation sequence more synchronised with the inverse of the depolarisation sequence, and likely increased regional heterogeneity of myocardial repolarisation. Studies investigating the relationship of these sex disparities to hormonal differences led frequently to conflicting results. Although sex hormones seem to play a key role by influencing both autonomic tone and electrophysiological properties at the cellular level, neither the truly relevant hormones nor their detailed actions are known. Physiologic usefulness of the described sex differences is also unknown. The review suggests that new studies are needed to advance the understanding of the physiologic mechanisms responsible for these inequalities between women and men and provides key methodological suggestions that need to be followed in future research.

Roles of Brain Angiotensin II in Cognitive Function and Dementia

The brain renin-angiotensin system (RAS) has been highlighted as having a pathological role in stroke, dementia, and neurodegenerative disease. Particularly, in dementia, epidemiological studies indicate a preventive effect of RAS blockade on cognitive impairment in Alzheimer disease (AD). Moreover, basic experiments suggest a role of brain angiotensin II in neural injury, neuroinflammation, and cognitive function and that RAS blockade attenuates cognitive impairment in rodent dementia models of AD. Therefore, RAS regulation is expected to have therapeutic potential for AD. Here, we discuss the role of angiotensin II in cognitive impairment and AD. Angiotensin II binds to the type 2 receptor (AT₂) and works mainly by binding with the type 1 receptor (AT₁). AT₂ receptor signaling plays a role in protection against multiple-organ damage. A direct AT₂ receptor agonist is now available and is expected to reduce inflammation and oxidative stress and enhance cell differentiation. We and other groups reported that AT₂ receptor activation enhances neuronal differentiation and neurite outgrowth in the brain. Here, we also review the effect of the AT₂ receptor on cognitive function. RAS modulation may be a new therapeutic option for dementia including AD in the future.

Metabolic syndrome and 16-year cognitive decline in community-dwelling older adults

PURPOSE

To determine whether metabolic syndrome is associated with accelerated cognitive decline in community-dwelling older adults.

METHODS

A longitudinal study of 993 adults (mean 66.8 ± 8.7 years) from the Rancho Bernardo Study. Metabolic syndrome components, defined by 2001 NCEP-ATP III criteria, were measured in 1984-1987. Cognitive function was first assessed in 1988-1992. Cognitive assessments were repeated approximately every 4 years, for a maximum 16-year follow-up. Mixed-effects models examined longitudinal rate of cognitive decline by metabolic syndrome status, controlling for factors plausibly associated with cognitive function (diabetes, inflammation).

RESULTS

Metabolic syndrome was more common in men than women (14% vs. 9%, p = .01). In women, metabolic syndrome was associated with greater executive function and long-term memory decline. These associations did not differ by inflammatory biomarker levels. Diabetes did not alter the association of metabolic syndrome with long-term recall but modified the association with executive function: metabolic syndrome was associated with accelerated executive function decline in diabetic women only. Metabolic syndrome was not related to rate of decline on any cognitive measure in men.

CONCLUSIONS

Metabolic syndrome was a risk factor for accelerated cognitive decline, but only in women. Prevention of metabolic syndrome may aid in maintenance of cognitive function with age.