Cardiovascular Risk Factors Associated with Smaller Brain Volumes in Regions Identified as Early Predictors of Cognitive Decline

Cardiovascular disease risk exacerbates brain aging among Hispanic/Latino adults in the SOL-INCA-MRI Study

Background

Cardiovascular disease (CVD) risk factors are highly prevalent among Hispanic/Latino adults, while the prevalence of MRI infarcts is not well-documented. We, therefore, sought to examine the relationships between CVD risk factors and infarcts with brain structure among Hispanic/Latino individuals.

Methods

Participants included 1,886 Hispanic/Latino adults (50-85 years) who underwent magnetic resonance imaging (MRI) as part of the Study of Latinos-Investigation of Neurocognitive Aging-MRI (SOL-INCA-MRI) study. CVD risk was measured approximately 10.5 years before MRI using the Framingham cardiovascular risk score, a measure of 10-year CVD risk (low (<10%), medium (10- < 20%), and high (≥20%)). MR infarcts were determined as present or absent. Outcomes included total brain, cerebral and lobar cortical gray matter, hippocampal, lateral ventricle, and total white matter hyperintensity (WMH) volumes. Linear regression models tested associations between CVD risk and infarct with MRI outcomes and for modifications by age and sex.

Results

Sixty percent of participants were at medium or high CVD risk. Medium and high CVD risk were associated with lower total brain and frontal gray matter and higher WMH volumes compared to those with low CVD risk. High CVD risk was additionally associated with lower total cortical gray matter and parietal volumes and larger lateral ventricle volumes. Men tended to have greater CVDRF-related differences in total brain volumes than women. The association of CVD risk factors on total brain volumes increased with age, equal to an approximate 7-year increase in total brain aging among the high-CVD-risk group compared to the low-risk group. The presence of infarct(s) was associated with lower total brain volumes, which was equal to an approximate 5-year increase in brain aging compared to individuals without infarcts. Infarcts were also associated with smaller total cortical gray matter, frontal and parietal volumes, and larger lateral ventricle and WMH volumes.

Conclusion

The high prevalence of CVD risk among Hispanic/Latino adults may be associated with accelerated brain aging.

Utility of multimodal longitudinal imaging data for dynamic prediction of cardiovascular and renal disease: the CARDIA study

Background

Medical examinations contain repeatedly measured data from multiple visits, including imaging variables collected from different modalities. However, the utility of such data for the prediction of time-to-event is unknown, and only a fraction of the data is typically used for risk prediction. We hypothesized that multimodal longitudinal imaging data could improve dynamic disease prognosis of cardiovascular and renal disease (CVRD).

Methods

In a multi-centered cohort of 5,114 CARDIA participants, we included 166 longitudinal imaging variables from five imaging modalities: Echocardiography (Echo), Cardiac and Abdominal Computed Tomography (CT), Dual-Energy x-ray Absorptiometry (DEXA), Brain Magnetic Resonance Imaging (MRI) collected from young adulthood to mid-life over 30 years (1985-2016) to perform dynamic survival analysis of CVRD events using machine learning dynamic survival analysis (Dynamic-DeepHit, LTRCforest, and Extended Cox for Time-varying Covariates). Risk probabilities were continuously updated as new data were collected. Model performance was assessed using integrated AUC and C-index and compared to traditional risk factors.

Results

Longitudinal imaging data, even when being irregularly collected with high missing rates, improved CVRD dynamic prediction (0.03 in integrated AUC, up to 0.05 in C-index compared to traditional risk factors; best model's C-index = 0.80-0.83 up to 20 years from baseline) from young adulthood followed up to midlife. Among imaging variables, Echo and CT variables contributed significantly to improved risk estimation. Echo measured in early adulthood predicted midlife CVRD risks almost as well as Echo measured 10-15 years later (0.01 C-index difference). The most recent CT exam provided the most accurate prediction for short-term risk estimation. Brain MRI markers provided additional information from cardiac Echo and CT variables that led to a slightly improved prediction.

Conclusions

Longitudinal multimodal imaging data readily collected from follow-up exams can improve CVRD dynamic prediction. Echocardiography measured early can provide a good long-term risk estimation, while CT/calcium scoring variables carry atherosclerotic signatures that benefit more immediate risk assessment starting in middle-age.

Associations of Triglycerides and Atherogenic Index of Plasma with Brain Structure in the Middle-Aged and Elderly Adults

Triglyceride (TG) and atherogenic index of plasma (AIP) have been acknowledged to be risk factors for vascular insults, but their impacts on the brain system remain elusive. To fill in some gaps, we investigated associations of TG and AIP with brain structure, leveraging the UK Biobank database. TG and high-density lipoprotein cholesterol (HDL-C) were examined at baseline and AIP was calculated as log (TG/HDL-C). We build several linear regression models to estimate associations of TG and AIP with volumes of brain grey matter phenotypes. Significant inverse associations of TG and AIP with volumes of specific subcortical traits were observed, among which TG and AIP were most significantly associated with caudate nucleus (TG: β [95% confidence interval CI] = -0.036 [-0.051, -0.022], AIP: -0.038 [-0.053, -0.023]), thalamus (-0.029 [-0.042, -0.017], -0.032 [-0.045, -0.019]). Higher TG and AIP were also considerably related with reduced cortical structure volumes, where two most significant associations of TG and AIP were with insula (TG: -0.035 [-0.048, -0.022], AIP: -0.038 [-0.052, -0.025]), superior temporal gyrus (-0.030 [-0.043, -0.017], -0.033 [-0.047, -0.020]). Modification effects of sex and regular physical activity on the associations were discovered as well. Our findings show adverse associations of TG and AIP with grey matter volumes, which has essential public health implications for early prevention in neurodegenerative diseases.

Garcia A, Buetow K, Thomas GS, Finch CE, Stieglitz J, Trumble BC, Gurven MD, Irimia A. Brain volume, energy balance, and cardiovascular health in two nonindustrial South American populations

Little is known about brain aging or dementia in nonindustrialized environments that are similar to how humans lived throughout evolutionary history. This paper examines brain volume (BV) in middle and old age among two indigenous South American populations, the Tsimane and Moseten, whose lifestyles and environments diverge from those in high-income nations. With a sample of 1,165 individuals aged 40 to 94, we analyze population differences in cross-sectional rates of decline in BV with age. We also assess the relationships of BV with energy biomarkers and arterial disease and compare them against findings in industrialized contexts. The analyses test three hypotheses derived from an evolutionary model of brain health, which we call the embarrassment of riches (EOR). The model hypothesizes that food energy was positively associated with late life BV in the physically active, food-limited past, but excess body mass and adiposity are now associated with reduced BV in industrialized societies in middle and older ages. We find that the relationship of BV with both non-HDL cholesterol and body mass index is curvilinear, positive from the lowest values to 1.4 to 1.6 SDs above the mean, and negative from that value to the highest values. The more acculturated Moseten exhibit a steeper decrease in BV with age than Tsimane, but still shallower than US and European populations. Lastly, aortic arteriosclerosis is associated with lower BV. Complemented by findings from the United States and Europe, our results are consistent with the EOR model, with implications for interventions to improve brain health.

Role of Citicoline in Patients With Mild Cognitive Impairment

The term mild cognitive impairment (MCI) defines an intermediate state between normal aging and dementia. Vascular cognitive impairment refers to a decline in cognitive function that is caused by or associated with vascular disease and comprises all the spectrum of cognitive impairments, from MCI of vascular origin to vascular dementia. One of the available treatments for cognitive impairment is cytidine diphosphate-choline (CDP-Choline), or citicoline. The objective of the present manuscript is to provide complete evidence about the efficacy of citicoline for MCI, especially of vascular origin, but also due to other neurodegenerative disorders. Citicoline is a pharmaceutical product constituted by the combination of 2 natural molecules (cytidine and choline) and is marketed as a food supplement. It has been proposed to provide neuroprotective effects through diverse mechanisms of action. Taking into account the available literature, citicoline has shown a consistent improvement in cognitive function in patients with MCI, especially of vascular origin. Moreover, it provides beneficial effects on vascular, Alzheimer, and mixed dementias, stroke sequelae, intracerebral hemorrhages, traumatic brain injuries, and neurodegenerative diseases. Long-term treatment with citicoline has also been demonstrated to be well-tolerated and has not been associated with severe adverse events. Citicoline is a safe, well-tolerated, and promising agent with evidenced neuroprotective properties.

Administration of Huperzine A microspheres ameliorates myocardial ischemic injury via α7nAChR-dependent JAK2/STAT3 signaling pathway

Acetylcholinesterase (AChE) inhibitor (AChEI) is well established as first-line agents for relieving the symptoms of Alzheimer's disease (AD). Injectable sustained-release formulation of AChEI may be suitable for treating AD patients. However, it needs to know whether continuous inhibition of AChE could deteriorate or attenuate myocardial damage if myocardial ischemia (MI) occurs. Huperzine A microspheres (HAM) are a sustained-release formulation releasing sustainably huperzine A (an AChEI) for more than 7 days after a single dose of HAM. This study aimed to investigate the myocardial damage in an isoprenaline (ISO)-induced MI mice model during HAM treatment. The heart injury was evaluated by assaying serum CK-MB, Tn-I and observing histopathological changes. The levels of proinflammatory cytokines in serum were detected. The level of p-P65 and the expression of proteins in the JAK2/STAT3 signaling pathway were assayed with Western blot. Administration with a single dose of HAM resulted in inhibiting the MI-induced increases of CK-MB and Tn-I, alleviating the damage of heart tissue, and decreasing the levels of TNF-α and IL-6. In addition, HAM decreased the levels of p-P65, p-JAK2, and p-STAT3 in heart tissue. The effects of HAM could be weakened or abolished by the specific α7nAChR antagonist. These findings suggest that continuous AChE inhibition could protect the heart from ischemic damage during administration of sustained-release formulation of AChEI, which is associated with the anti-inflammatory effect of HAM by regulating α7nAChR-dependent JAK2/STAT3 signaling pathway.

Disrupted resting-state functional connectivity of the thalamus in patients with coronary heart disease

Background

Although homeostasis of the cardiovascular system is regulated by the cerebral cortex via the autonomic nervous system, the role of abnormal brain functional connectivity (FC) networks in patients with cardiac dysfunction remains unclear. Here, we report thalamus-based FC alterations and their relationship with clinical characteristics in patients with coronary heart disease (CHD).

Methods

We employed resting-state functional magnetic resonance imaging (rs-fMRI) to acquire imaging data in twenty-six patients with CHD alongside sixteen healthy controls (HCs). Next, we performed a thalamus-based FC analysis to profile abnormal FC patterns in the whole brain. Subsequently, the mean time series of the brain regions that survived in the FC analysis were used to determine correlations with clinical parameters in patients with CHD.

Results

We found no statistically significant differences in demographic and clinical data between patients with CHD and HCs. Patients with CHD showed decreased FC patterns between bilateral thalami and left hemisphere, encompassing supplementary motor area, superior frontal gyrus, superior parietal gyrus, inferior parietal gyrus, middle cingulate cortex, lingual gyrus and calcarine sulcus.

Conclusions

These findings not only have implications in clarifying the relationship between cerebral functional imbalance and cardiovascular system, but also provide valuable insights to guide future evaluation and management of cardiac autonomic regulation via the brain-heart axis.

Cingulate and hippocampal subregion abnormalities in combat-exposed veterans with PTSD

BACKGROUND

The hippocampus and cingulate gyrus are strongly interconnected brain regions that have been implicated in the neurobiology of post-traumatic stress disorder (PTSD). These brain structures are comprised of functionally distinct subregions that may contribute to the expression of PTSD symptoms or associated cardio-metabolic markers, but have not been well investigated in prior studies.

METHODS

Two divisions of the cingulate cortex (i.e., rostral and caudal) and 11 hippocampal subregions were investigated in 22 male combat-exposed veterans with PTSD and 22 male trauma-exposed veteran controls (TC). Cardio-metabolic measures included cholesterol, body mass index, and mean arterial pressure.

RESULTS

Individuals with PTSD had less caudal cingulate area compared to TC even after controlling for caudal cingulate thickness. Total hippocampus volume was lower in PTSD compared to TC, accounted for by differences in CA1-CA4, granule cell layer of the dentate gyrus, molecular layer, and subiculum. Individuals with PTSD had higher mean arterial pressure compared to TC, which correlated with hippocampus volume only in the PTSD group.

LIMITATIONS

Sample size, cross-sectional analysis, no control for medications and findings limited to males.

CONCLUSIONS

These data demonstrate preferential involvement of caudal cingulate area (vs. thickness) and hippocampus subregions in PTSD. The inverse association between hippocampus volume and mean arterial pressure may contribute to accelerated aging known to be associated with PTSD.

Multiple Sclerosis and the Risk of Cardiovascular Diseases: A Mendelian Randomization Study

BACKGROUND

Observational studies suggested that multiple sclerosis (MS) is associated with cardiovascular diseases (CVDs). However, the causal association has not been fully elucidated. Thus, we aim to assess the causality of the associations of MS with risk of CVDs.

METHODS

A two-sample Mendelian randomization (MR) study was performed to explore the causality. Genetic instruments were identified for MS from a genome-wide association study (GWAS) involving 115,803 individuals. Summary-level data for CVDs were obtained from different GWAS meta-analysis studies. MR analysis was conducted mainly using the inverse-variance weighted (IVW) method. Sensitivity analyses were further performed to ensure the robustness of the results.

RESULTS

This MR study found suggestive evidence that genetic liability to MS was associated with an increased risk of coronary artery disease (CAD) [odds ratio (OR), 1.02; 95% confidence interval (CI), 1.00-1.04; p = 0.03], myocardial infarction (MI) (OR, 1.03; 95% CI, 1.00-1.06; p = 0.01), heart failure (HF) (OR, 1.02; 95% CI, 1.00-1.04; p = 0.02), all-cause stroke (AS) (OR, 1.02; 95% CI, 1.00-1.05; p = 0.02), and any ischemic stroke (AIS) (OR, 1.02; 95% CI, 1.00-1.05; p = 0.04). The null-association was observed between MS and the other CVDs. Further analyses found little evidence of pleiotropy.

CONCLUSIONS

We provided suggestive genetic evidence for the causal associations of MS with increased risk of CAD, MI, HF, AS, and AIS, which highlighted the significance of active monitoring and prevention of cardiovascular risk to combat cardiovascular comorbidities in MS patients.

Integrating multiple brain imaging modalities does not boost prediction of subclinical atherosclerosis in midlife adults

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Brain measures from MRI do not improve Framingham Risk Score prediction of CA-IMT.

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Prediction stacking is a flexible approach to determine added predictive utility.

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Multimodal stacking can be applied to individual difference factors.

Background

Human neuroimaging evidence suggests that cardiovascular disease (CVD) risk may relate to functional and structural features of the brain. The present study tested whether combining functional and structural (multimodal) brain measures, derived from magnetic resonance imaging (MRI), would yield a multivariate brain biomarker that reliably predicts a subclinical marker of CVD risk, carotid-artery intima-media thickness (CA-IMT).

Methods

Neuroimaging, cardiovascular, and demographic data were assessed in 324 midlife and otherwise healthy adults who were free of (a) clinical CVD and (b) use of medications for chronic illnesses (aged 30–51 years, 49% female). We implemented a prediction stacking algorithm that combined multimodal brain imaging measures and Framingham Risk Scores (FRS) to predict CA-IMT. We included imaging measures that could be easily obtained in clinical settings: resting state functional connectivity and structural morphology measures from T1-weighted images.

Results

Our models reliably predicted CA-IMT using FRS, as well as for several individual MRI measures; however, none of the individual MRI measures outperformed FRS. Moreover, stacking functional and structural brain measures with FRS did not boost prediction accuracy above that of FRS alone.

Conclusions

Combining multimodal functional and structural brain measures through a stacking algorithm does not appear to yield a reliable brain biomarker of subclinical CVD, as reflected by CA-IMT.

Regional brain volumes relate to Alzheimer's disease cerebrospinal fluid biomarkers and neuropsychometry: A cross-sectional, observational study

We hypothesized that automated assessment of brain volumes on MRI can predict presence of cerebrospinal fluid abnormal ß-amyloid42 and Tau protein levels and thus serve as a useful screening test for possible Alzheimer's disease. 113 participants ranging from cognitively healthy to Alzheimer's disease underwent MRI exams to obtain measurements of hippocampus, prefrontal cortex, precuneus, parietal cortex, and occipital lobe volumes. A non-exclusive subset (n = 107) consented to lumbar punctures to obtain cerebrospinal fluid for ß-amyloid42 and Tau protein assessment including cognitively health (n = 75), mild cognitively impaired (n = 22), and Alzheimer's disease (n = 10). After adjustment for false discovery rate, ß-amyloid42 was significantly associated with volumes in the hippocampus (p = 0.043), prefrontal cortex (p = 0.010), precuneus (p = 0.024), and the posterior cingulate (p = 0.002). No association between Tau levels and regional brain volume survived multiple test correction. Secondary analysis was performed to determine associations between MRI brain volumes and CSF protein levels to neuropsychological impairment. A non-exclusive subset (n = 96) including cognitively healthy (n = 72), mild cognitively impaired (n = 21), and Alzheimer's disease (n = 3) participants underwent Stroop Interference and Boston Naming neuropsychological testing. A higher score on the Boston Naming Test was optimally predicted in a selective regression model by greater hippocampus volume (p = 0.002), a higher ratio of ß-amyloid42 to Tau protein levels (p < 0.001), greater posterior cingulate volume (p = 0.0193), age (p = 0.0271), and a higher education level (p = 0.002). A better performance on the Stroop Interference Test was optimally predicted by greater hippocampus volume (p = 0.0003) and a higher education level (p < 0.001). Lastly, impaired cognitive status (mild cognitive impairment and Alzheimer's Disease) was optimally predicted in a selective regression model by a worse performance on the Stroop Interference Test (p < 0.001), a worse performance on the Boston Naming Test (p < 0.001), along with lower prefrontal cortex volume (p = 0.002) and lower hippocampus volume (p = 0.007).

The effects of age on resting-state BOLD signal variability is explained by cardiovascular and cerebrovascular factors

Accurate identification of brain function is necessary to understand neurocognitive aging, and thereby promote health and well-being. Many studies of neurocognitive aging have investigated brain function with the blood-oxygen level-dependent (BOLD) signal measured by functional magnetic resonance imaging. However, the BOLD signal is a composite of neural and vascular signals, which are differentially affected by aging. It is, therefore, essential to distinguish the age effects on vascular versus neural function. The BOLD signal variability at rest (known as resting state fluctuation amplitude, RSFA), is a safe, scalable, and robust means to calibrate vascular responsivity, as an alternative to breath-holding and hypercapnia. However, the use of RSFA for normalization of BOLD imaging assumes that age differences in RSFA reflecting only vascular factors, rather than age-related differences in neural function (activity) or neuronal loss (atrophy). Previous studies indicate that two vascular factors, cardiovascular health (CVH) and cerebrovascular function, are insufficient when used alone to fully explain age-related differences in RSFA. It remains possible that their joint consideration is required to fully capture age differences in RSFA. We tested the hypothesis that RSFA no longer varies with age after adjusting for a combination of cardiovascular and cerebrovascular measures. We also tested the hypothesis that RSFA variation with age is not associated with atrophy. We used data from the population-based, lifespan Cam-CAN cohort. After controlling for cardiovascular and cerebrovascular estimates alone, the residual variance in RSFA across individuals was significantly associated with age. However, when controlling for both cardiovascular and cerebrovascular estimates, the variance in RSFA was no longer associated with age. Grey matter volumes did not explain age differences in RSFA, after controlling for CVH. The results were consistent between voxel-level analysis and independent component analysis. Our findings indicate that cardiovascular and cerebrovascular signals are together sufficient predictors of age differences in RSFA. We suggest that RSFA can be used to separate vascular from neuronal factors, to characterize neurocognitive aging. We discuss the implications and make recommendations for the use of RSFA in the research of aging.

Elevated lipids are associated with reduced regional brain structure in youth with bipolar disorder

OBJECTIVE

Abnormal blood lipid levels are common in bipolar disorder (BD) and correlate with mood symptoms and neurocognition. However, studies have not examined the lipid-brain structure association in BD or youth.

METHODS

This study examined low-density lipoprotein (LDL-C), high-density lipoprotein (HDL-C), triglycerides, and total cholesterol (TC) levels in relation to brain structure utilizing T1-weighted images, among participants ages 13-20 with BD (n = 55) and healthy controls (HC; n = 47). General linear models investigated group differences in the association of lipids with anterior cingulate cortex (ACC), hippocampus, and inferior parietal lobe structure, controlling for age, sex, body mass index, and intracranial volume. For significant associations, post hoc within-group analyses were undertaken. Exploratory vertex-wise analyses further investigated group differences in the lipid-brain structure association.

RESULTS

There were significant group differences in the association of LDL-C (β = -0.29 p = 0.001), and TC (β = -0.21 p = 0.016), with hippocampal volume, and triglycerides with ACC volume (β = -0.25 p = 0.01) and area (β = -0.26 p = 0.004). Elevated lipids were associated with smaller brain structure to a significantly greater extent in BD vs HC. Post hoc analyses revealed that elevated LDL-C (β = -0.27 p = 0.007) and reduced HDL-C (β = 0.24 p = 0.01) were associated with smaller hippocampal volume in the BD group. Exclusion of BD second-generation antipsychotic users did not alter these results. Vertex-wise analyses further showed that elevated lipids were associated with smaller brain structure to a significantly greater extent in BD vs HC, across the cortex.

CONCLUSION

Elevated lipids are associated with smaller brain structure in BD. Research evaluating lipid-brain structure associations prospectively and whether lipid optimization has salutary effects on brain structure is necessary.

Association of mid-life serum lipid levels with late-life brain volumes: The atherosclerosis risk in communities neurocognitive study (ARICNCS)

BACKGROUND

Limited information exists regarding the association between midlife lipid levels and late-life total and regional brain volumes.

METHODS

We studied 1872 participants in the longitudinal community-based Atherosclerosis Risk in Communities Neurocognitive Study. Serum lipid levels were measured in 1987-1989 (mean age, 53 ± 5 years). Participants underwent 3T brain MRI scans in 2011-2013. Brain volumes were measured using FreeSurfer image analysis software. Linear regression models were used to assess the associations between serum lipids and brain volumes modeled in standard deviation (SD) units, adjusting for potential confounders.

RESULTS

In adjusted analyses, one SD higher low-density lipoprotein cholesterol (LDL) levels were associated with larger total brain volumes (β 0.033, 95% CI 0.006-0.060) as well as larger volumes of the temporal (β 0.038, 95% CI 0.003-0.074) and parietal lobes (β 0.044, 95% CI 0.009-0.07) and Alzheimer disease-related region (β 0.048, 95% CI 0.048-0.085). Higher triglyceride levels were associated with smaller total brain volumes (β -0.033, 95% CI -0.060, -0.007). The associations between LDL levels and brain volumes were modified by age (P for interaction <0.001), with higher LDL levels associated with larger total and regional brain volumes only among adults >53 years at baseline, and were attenuated after application of weights to account for informative attrition, although associations with the parietal and Alzheimer's disease-related region remained significant. High-density lipoprotein cholesterol was not associated with brain volumes.

CONCLUSION

Higher LDL levels in late midlife were associated with larger brain volumes later in life, while higher triglyceride levels were associated with smaller brain volumes. These associations were driven by adults >53 years at baseline.

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.

Epidemiology and treatment of multiple sclerosis in elderly populations

The prevalence of multiple sclerosis (MS) and the age of affected patients are increasing owing to increased longevity of the general population and the availability of effective disease-modifying therapies. However, ageing presents unique challenges in patients with MS largely as a result of their increased frequency of age-related and MS-related comorbidities as well as transition of the disease course from an inflammatory to a neurodegenerative phenotype. Immunosenescence (the weakening of the immune system associated with natural ageing) might be at least partly responsible for this transition, which further complicates disease management. Currently approved therapies for MS are effective in preventing relapse but are not as effective in preventing the accumulation of disability associated with ageing and disease progression. Thus, ageing patients with MS represent a uniquely challenging population that is currently underserved by existing therapeutic regimens. This Review focuses on the epidemiology of MS in ageing patients. Unique considerations relevant to this population are discussed, including the immunology and pathobiology of the complex relationship between ageing and MS, the safety and efficacy of disease-modifying therapies, when discontinuation of treatment might be appropriate and the important role of approaches to support wellness and cognition.

Brain Perfusion Change in Patients with Mild Cognitive Impairment After 12 Months of Aerobic Exercise Training

Aerobic exercise (AE) has recently received increasing attention in the prevention of Alzheimer's disease (AD). There is some evidence that it can improve neurocognitive function in elderly individuals. However, the mechanism of these improvements is not completely understood. In this prospective clinical trial, thirty amnestic mild cognitive impairment participants were enrolled into two groups and underwent 12 months of intervention. One group (n = 15) performed AE training (8M/7F, age = 66.4 years), whereas the other (n = 15) performed stretch training (8M/7F, age = 66.1 years) as a control intervention. Both groups performed 25-30 minutes training, 3 times per week. Frequency and duration were gradually increased over time. Twelve-month AE training improved cardiorespiratory fitness (p = 0.04) and memory function (p = 0.004). Cerebral blood flow (CBF) was measured at pre- and post-training using pseudo-continuous-arterial-spin-labeling MRI. Relative to the stretch group, the AE group displayed a training-related increase in CBF in the anterior cingulate cortex (p = 0.016). Furthermore, across individuals, the extent of memory improvement was associated with CBF increases in anterior cingulate cortex and adjacent prefrontal cortex (voxel-wise p < 0.05). In contrast, AE resulted in a decrease in CBF of the posterior cingulate cortex, when compared to the stretch group (p = 0.01). These results suggest that salutary effects of AE in AD may be mediated by redistribution of blood flow and neural activity in AD-sensitive regions of brain.

Associations of Regional Brain Structural Differences With Aging, Modifiable Risk Factors for Dementia, and Cognitive Performance

IMPORTANCE

Identifying brain regions associated with risk factors for dementia could guide mechanistic understanding of risk factors associated with Alzheimer disease (AD).

OBJECTIVES

To characterize volume changes in brain regions associated with aging and modifiable risk factors for dementia (MRFD) and to test whether volume differences in these regions are associated with cognitive performance.

DESIGN, SETTING, AND PARTICIPANTS

This cross-sectional study used data from UK Biobank participants who underwent T1-weighted structural brain imaging from August 5, 2014, to October 14, 2016. A voxelwise linear model was applied to test for regional gray matter volume differences associated with aging and MRFD (ie, hypertension, diabetes, obesity, and frequent alcohol use). The potential clinical relevance of these associations was explored by comparing their neuroanatomical distributions with the regional brain atrophy found with AD. Mediation models for risk factors, brain volume differences, and cognitive measures were tested. The primary hypothesis was that common, overlapping regions would be found. Primary analysis was conducted on April 1, 2018.

MAIN OUTCOMES AND MEASURES

Gray matter regions that showed relative atrophy associated with AD, aging, and greater numbers of MRFD.

RESULTS

Among 8312 participants (mean [SD] age, 62.4 [7.4] years; 3959 [47.1%] men), aging and 4 major MRFD (ie, hypertension, diabetes, obesity, and frequent alcohol use) had independent negative associations with specific gray matter volumes. These regions overlapped neuroanatomically with those showing lower volumes in participants with AD, including the posterior cingulate cortex, the thalamus, the hippocampus, and the orbitofrontal cortex. Associations between these MRFD and spatial memory were mediated by differences in posterior cingulate cortex volume (β = 0.0014; SE = 0.0006; P = .02).

CONCLUSIONS AND RELEVANCE

This cross-sectional study identified differences in localized brain gray matter volume associated with aging and MRFD, suggesting regional vulnerabilities. These differences appeared relevant to cognitive performance even among people considered cognitively healthy.

A genome-wide association study identifies genetic loci associated with specific lobar brain volumes

Brain lobar volumes are heritable but genetic studies are limited. We performed genome-wide association studies of frontal, occipital, parietal and temporal lobe volumes in 16,016 individuals, and replicated our findings in 8,789 individuals. We identified six genetic loci associated with specific lobar volumes independent of intracranial volume. Two loci, associated with occipital (6q22.32) and temporal lobe volume (12q14.3), were previously reported to associate with intracranial and hippocampal volume, respectively. We identified four loci previously unknown to affect brain volumes: 3q24 for parietal lobe volume, and 1q22, 4p16.3 and 14q23.1 for occipital lobe volume. The associated variants were located in regions enriched for histone modifications (DAAM1 and THBS3), or close to genes causing Mendelian brain-related diseases (ZIC4 and FGFRL1). No genetic overlap between lobar volumes and neurological or psychiatric diseases was observed. Our findings reveal part of the complex genetics underlying brain development and suggest a role for regulatory regions in determining brain volumes.

Associations between subclinical depressive symptoms and reduced brain volume in middle-aged to older adults

OBJECTIVES

The associations between subclinical depressive symptoms, as well specific symptom subscales, on brain structure in aging are not completely elucidated. This study investigated the extent to which depressive symptoms were related to brain volumes in fronto-limbic structures in a sample of middle-aged to older adults.

METHOD

Eighty participants underwent structural neuroimaging and completed the Beck Depression Inventory, 2nd Edition (BDI-II), which comprises separate affective, cognitive, and somatic subscales. Gray matter volumes were extracted from the caudal and rostral anterior cingulate, posterior cingulate, hippocampus, and amygdala. Hierarchical regression models examined the relationship between brain volumes and (i) total depressive symptoms and (ii) BDI-II subscales were conducted.

RESULTS

After adjusting for total intracranial volume, race, and age, higher total depressive symptoms were associated with smaller hippocampal volume (p = 0.005). For the symptom subscales, after controlling for the abovementioned covariates and the influence of the other symptom subscales, more somatic symptoms were related to smaller posterior cingulate (p = 0.025) and hippocampal (p < 0.001) volumes. In contrast, the affective and cognitive subscales were not associated with brain volumes in any regions of interest.

CONCLUSION

Our data showed that greater symptomatology was associated with smaller volume in limbic brain regions. These findings provide evidence for preclinical biological markers of major depression and specifically advance knowledge of the relationship between subclinical depressive symptoms and brain volume. Importantly, we observed variations by specific depressive symptom subscales, suggesting a symptom-differential relationship between subclinical depression and brain volume alterations in middle-aged and older individuals.

Vascular aspects of multiple sclerosis: emphasis on perfusion and cardiovascular comorbidities

INTRODUCTION

Multiple sclerosis (MS) is a chronic inflammatory, demyelinating, and neurodegenerative disease of the central nervous system. Over the last two decades, more favorable MS long-term outcomes have contributed toward increase in prevalence of the aged MS population. Emergence of age-associated pathology, such as cardiovascular diseases, may interact with the MS pathophysiology and further contribute to disease progression. Areas covered: This review summarizes the cardiovascular involvement in MS pathology, its disease activity, and progression. The cardiovascular health, the presence of various cardiovascular diseases, and their effect on MS cognitive performance are further explored. In similar fashion, the emerging evidence of a higher incidence of extracranial arterial pathology and its association with brain MS pathology are discussed. Finally, the authors outline the methodologies behind specific perfusion magnetic resonance imaging (MRI) and ultrasound Doppler techniques, which allow measurement of disease-specific and age-specific vascular changes in the aging population and MS patients. Expert opinion: Cardiovascular pathology significantly contributes to worse clinical and MRI-derived disease outcomes in MS. Global and regional cerebral hypoperfusion may be associated with poorer physical and cognitive performance. Prevention, improved detection, and treatment of the cardiovascular-based pathology may improve the overall long-term health of MS patients.

Dietary and lifestyle factors in multiple sclerosis progression: results from a 5-year longitudinal MRI study

BACKGROUND

Evidence regarding the role, if any, of dietary and lifestyle factors in the pathogenesis of multiple sclerosis (MS) is poorly understood.

OBJECTIVE

To assess the effect of lifestyle-based risk factors linked to cardiovascular disease (CVD) on clinical and MRI-derived MS outcomes.

METHODS

The study enrolled 175 MS or clinically isolated syndrome (CIS) patients and 42 age- and sex-matched healthy controls (HCs) who were longitudinally followed for 5.5 years. The 20-year CVD risk was calculated by Healthy Heart Score (HHS) prediction model which includes age, smoking, body mass index, dietary intake, exercise, and alcohol consumption. Baseline and follow-up MRI scans were obtained and cross-sectional and longitudinal changes of T2-lesion volume (LV), whole brain volume (WBV), white matter volume (WMV), gray matter volume (GMV), and lateral ventricular volume (LVV) were calculated.

RESULTS

After correcting for disease duration, the baseline HHS values of the MS group were associated with baseline GMV (r_s = - 0.20, p = 0.01), and longitudinal LVV change (r_s = 0.19, p = 0.01). The association with LVV remained significant after adjusting for baseline LVV volumes (r_s = 0.2, p = 0.008) in MS patients. The diet component of the HHS was associated with the 5-year T2-LV accrual (r_s = - 0.191, p = 0.04) in MS. In the HC group, the HHS was associated with LVV (r_s = 0.58, p < 0.001), GMV (r_s = - 0.57, p < 0.001), WBV (r_s = - 0.55, p = 0.001), T2-LV (r_s = 0.41, p = 0.027), and WMV (r_s = - 0.38, p = 0.042). Additionally, the HC HHS was associated with the 5-year change in LVV (r_s = 0.54, p = 0.001) and in WBV (r_s = - 0.45, p = 0.011).

CONCLUSION

Lifestyle risk factors contribute to accelerated central brain atrophy in MS patients, whereas unhealthier diet is associated with MS lesion accrual. Despite the lower overall effect when compared to HCs, lifestyle-based modifications may still provide a beneficial effect on reducing brain atrophy in MS patients.

Distinguishing Brain Impact of Aging and HIV Severity in Chronic HIV Using Multiparametric MR Imaging and MR Spectroscopy

Background

Combination antiretroviral therapy (cART) has transformed HIV into a manageable but complex chronic disease, in which it is uncertain which brain insults may relate to age vs initial disease severity. We evaluate N-acetyl-aspartate/creatine (NAA/Cr), white matter hyperintensities (WMH), and mean cortical thickness to identify which subclinical markers of brain insult best relate to CD4 nadir and aging. This is a prospective study of the association between brain markers with age and initial infection severity, based on CD4 nadir, in chronic HIV patients.

Methods

Thirty-seven chronic HIV patients (age 25–77 years) with successful viral suppression were scanned on a GE 3T magnetic resonance imaging scanner to obtain NAA/Cr (standardized and averaged over 5 brain regions), log-transformed WMH volume, and mean cortical thickness. The brain measures were fitted with both CD4 nadir and age to evaluate the significance of their relationship.

Results

NAA/Cr, WMH, and cortical thickness were all correlated with age and CD4 nadir in unadjusted associations. Stepwise regression models showed that NAA/Cr alone best predicted CD4 nadir (β = 40.1 ± 13.3; P = .005), whereas WMH (β = 2.3 ± .9; P = .02) and mean cortical thickness (β = –2.7 ± 6.6; P < .0001) together produced the best model fit with age. NAA/Cr was higher for HIV stage 1 (CD4 nadir ≥ 500 cells/ µL; n = 15) compared with stage 2 (200 ≥ CD4 nadir < 500; n = 13) and stage 3 (CD4 nadir < 200; n = 9; P < .01 for both).

Conclusions

In patients with effectively suppressed HIV, NAA reflects the subclinical brain impact of initial disease severity related to development of even mild immune compromise, whereas cortical thickness and WMH volume are useful to evaluate age-related changes.

Validity of a method for the self-screening of cardiovascular risk

Background

The validity of a cardiovascular risk self-screening method was assessed. The results obtained for self-measurement of blood pressure, a point-of-care system’s assessment of lipid profile and glycated hemoglobin, and a self-administered questionnaire (sex, age, diabetes, tobacco consumption) were compared with the standard screening (gold standard) conducted by a health professional.

Methods

Crossover clinical trial on a population-based sample from Girona (north-eastern Spain), aged 35–74, with no cardiovascular disease at recruitment. Participants were randomized to one of the two risk assessment sequences (standard screening followed by self-screening or vice versa). Cardiovascular risk was estimated with the Framingham-REGICOR function. Concordance between methods was estimated with the intraclass correlation coefficient (ICC). Sensitivity, specificity, and positive and negative predictive values were estimated, considering 5% cardiovascular risk as the cutoff point. ClinicalTrials.gov Registration #NCT02373319. Clinical Research Ethic Committee of the Parc de Salut Mar Registration #2014/5815/I.

Results

The median cardiovascular risk in men was 2.56 (interquartile range: 1.42–4.35) estimated by standard methods and 2.25 (1.28–4.07) by self-screening with ICC=0.92 (95% CI: 0.90–0.93). In women, the cardiovascular risk was 1.14 (0.61–2.10) by standard methods and 1.10 (0.56–2.00) by self-screening, with ICC=0.89 (0.87–0.90). The sensitivity, specificity, and positive and negative predictive values for the self-screening method were 0.74 (0.63–0.82), 0.97 (0.95–0.99), 0.86 (0.77–0.93), and 0.94 (0.91–0.96), respectively, in men. In women, these values were 0.50 (0.30–0.70), 0.99 (0.98–1), 0.81 (0.54–0.96), and 0.97 (0.95–0.99), respectively.

Conclusion

The self-screening method for assessing cardiovascular risk provided similar results to the standard method. Self-screening had high clinical performance to rule out intermediate or high cardiovascular risk.

Cerebral blood flow velocity positively correlates with brain volumes in long-term remitted depression

BACKGROUND

Mechanisms involved in brain changes observed in major depression have been poorly investigated in clinical populations. Changes in cerebral blood flow (CBF) have been found in depressed patients and constitute a potential mechanism by which brain volume varies in depression. We have tested the association of cerebral blood flow velocity (CBFV) as assessed with Transcranial Doppler (TCD) and cerebral blood flow (CBF) as assessed with Arterial Spin Labeling Magnetic Resonance Imaging (ASL-MRI) with Total Brain Volume (TBV) and the volume of seven subcortical regions, in currently depressed and long-term remitted patients. In addition, we have evaluated other potential confounders for the association depression/brain volume, including dimensional symptoms of depression, cardiovascular risk factors (CVRF) and antidepressants.

METHODS

Seventy-five individuals were recruited, divided in 3 equal groups (currently depressed, remitted individuals and healthy controls) and were submitted to clinical assessment, MRI and Transcranial Doppler.

RESULTS

CBFV was positively correlated with TBV, Hippocampus and Thalamus volume, but only in remitted patients, who tend to have larger brains compared to both currently depressed and controls. CVRF were negatively associated with brain volumes in the 3 groups and antidepressant use was associated with larger Thalamus. We found no association between brain volumes and CBF as assessed with ASL-MRI, anhedonia, anxiety or psychomotor retardation.

DISCUSSION

Greater CBFV may be a physiological mechanism by which brain is enlarged in remitted patients. Future studies should consider CBFV, CVRF and antidepressants as possible confounders for the association depression/brain volumes, especially in remitted patients.

The Cerebral Brain-Derived Neurotrophic Factor Pathway, Either Neuronal or Endothelial, Is Impaired in Rats with Adjuvant-Induced Arthritis. Connection with Endothelial Dysfunction

Cognitive abilities are largely dependent on activation of cerebral tropomyosin-related kinase B receptors (TrkB) by brain-derived neurotrophic factor (BDNF) that is secreted under a bioactive form by both neurons and endothelial cells. In addition, there is mounting evidence for a link between endothelial function and cognition even though the underlying mechanisms are not well known. Therefore, we investigated the cerebral BDNF pathway, either neuronal or endothelial, in rheumatoid arthritis (RA) that combines both endothelial dysfunction (ED) and impaired cognition. Adjuvant-induced arthritis (AIA) in rats was used as a model of RA. Clinical inflammatory symptoms were evaluated from an arthritis score and brains were collected at day 31 ± 2 post-immunization. Neuronal expression of BDNF and TrkB phosphorylated at tyrosine 816 (p-TrkB) was examined in brain slices. Endothelial BDNF and p-TrkB expression was examined on both brain slices (hippocampal arterioles) and isolated cerebral microvessels-enriched fractions (vessels downstream to arterioles). The connection between endothelial nitric oxide (NO) and BDNF production was explored on the cerebrovascular fractions using endothelial NO synthase (eNOS) levels as a marker of NO production, N^ω-Nitro-L-arginine methyl ester hydrochloride (L-NAME) as a NOS inhibitor and glyceryl-trinitrate as a slow releasing NO donor. Brain slices displayed lower BDNF and p-TrkB staining in both neurons and arteriolar endothelial cells in AIA than in control rats. For endothelial cells but not neurons, a strong correlation was observed between BDNF and p-TrkB staining. Of note, a strong correlation was also observed between neuronal p-TrkB and endothelial BDNF staining. In cerebral microvessels-enriched fractions, AIA led to decreased BDNF and eNOS levels with a positive association between the 2 parameters. These effects coincided with decreased BDNF and p-TrkB staining in endothelial cells. The exposure of AIA cerebrovascular fractions to GTN increased BDNF levels while the exposure of control fractions to L-NAME decreased BDNF levels. Changes in the cerebral BDNF pathway were not associated with arthritis score. The present study reveals that AIA impairs the endothelial and neuronal BDNF/TrkB pathway, irrespective of the severity of inflammatory symptoms but dependent on endothelial NO production. These results open new perspectives for the understanding of the link between ED and impaired cognition.

Midlife Work-Related Stress is Associated with Late-Life Gray Matter Volume Atrophy

Background:

Work-related stress has been associated with an increased dementia risk. However, less is known about the mechanisms that underlie these associations.

Objective:

The goal is to examine associations between midlife work-related stress and late-life structural brain alterations.

Methods:

The Cardiovascular Risk Factors, Aging, and Dementia (CAIDE) study participants were randomly selected from independent population-based surveys (mean age 50) in Finland. MRI measurements included gray matter (GM) volume, white matter lesions (WML) and medial temporal atrophy (MTA) (1st re-examination, n = 102); and GM volume, hippocampal volume, WML volume, cortical thickness, and MTA (2nd re-examination, n = 64). Work-related stress comprised a score from two questions administered in midlife.

Results:

Higher levels of midlife work-related stress were associated with lower GM volume (β= –0.077, p = 0.033) at the first re-examination, even after adjusting for several confounders. No significant associations were found with MTA, WML, or MRI measurements at the second re-examination.

Conclusion:

Previously shown associations of midlife work-related stress with dementia risk may be at least partly explained by associations with lower GM volume in late-life. The lack of associations at the second re-examination may indicate a critical time window for the effects of midlife work-related stress, and/or selective survival/participation.

Left Ventricular Mass, Brain Magnetic Resonance Imaging, and Cognitive Performance: Results From the Strong Heart Study

Left ventricular mass (LVM) has been shown to serve as a measure of target organ damage resulting from chronic exposure to several risk factors. Data on the association of midlife LVM with later cognitive performance are sparse. We studied 721 adults (mean age 56 years at baseline) enrolled in the Strong Heart Study (SHS, 1993-1995) and the ancillary CDCAI (Cerebrovascular Disease and Its Consequences in American Indians) Study (2010-2013), a study population with high prevalence of cardiovascular disease. LVM was assessed with transthoracic echocardiography at baseline in 1993 to 1995. Cranial magnetic resonance imaging and cognitive testing were undertaken between 2010 and 2013. Generalized estimating equations were used to model associations between LVM and later imaging and cognition outcomes. The mean follow-up period was 17 years. A difference of 25 g in higher LVM was associated with marginally lower hippocampal volume (0.01%; 95% confidence interval, 0.02-0.00; P=0.001) and higher white matter grade (0.10; 95% confidence interval, 0.02-0.18; P=0.014). Functionally, participants with higher LVM tended to have slightly lower scores on the modified mini-mental state examination (0.58; 95% confidence interval, 1.08-0.08; P=0.024). The main results persisted after adjusting for blood pressure levels or vascular disease. The small overall effect sizes are partly explained by survival bias because of the high prevalence of cardiovascular disease in our population. Our findings emphasize the role of cardiovascular health in midlife as a target for the prevention of deleterious cognitive and functional outcomes in later life.

Magnetic Resonance Imaging of Cardiovascular Function and the Brain: Is Dementia a Cardiovascular-Driven Disease?

The proximal aorta acts as a coupling device between heart and brain perfusion, modulating the amount of pressure and flow pulsatility transmitted into the cerebral microcirculation. Stiffening of the proximal aorta is strongly associated with age and hypertension. The detrimental effects of aortic stiffening may result in brain damage as well as heart failure. The resulting cerebral small vessel disease and heart failure may contribute to early cognitive decline and (vascular) dementia. This pathophysiological sequence of events underscores the role of cardiovascular disease as a contributory mechanism in causing cognitive decline and dementia and potentially may provide a starting point for prevention and treatment. Magnetic resonance imaging is well suited to assess the function of the proximal aorta and the left ventricle (eg, aortic arch pulse wave velocity and distensibility) as well as the various early and late manifestations of cerebral small vessel disease (eg, microbleeds and white matter hyperintensities in strategically important regions of the brain). Specialized magnetic resonance imaging techniques are explored for diagnosing preclinical changes in white matter integrity or brain microvascular pulsatility.

Montreal Cognitive Assessment Performance among Community-Dwelling African Americans

Objective

To report descriptive and normative data for the Montreal Cognitive Assessment (MoCA) in a population-based African American sample.

Method

The MoCA was administered to 1,419 African American participants (mean age 49.89 years, range 18-75, 64% female). After excluding those with subjective cognitive complaints (n = 301), normative data were generated by education and overlapping age ranges (n = 1,118). Pearson correlations and analysis of variance were used to examine the relationship to demographic variables, and frequency of missed items was reviewed.

Results

Total MoCA scores (mean 22.3, SD 3.9) were lower than previously published normative data derived from an elderly Caucasian Canadian population with 80% falling below the suggested cutoff (<26) for impairment. Several MoCA items were missed by a large portion of the sample, including cube drawing (72%), delayed free recall (66% <4/5 words), sentence repetition (63%), and abstraction items (45%).

Conclusion

This is the first study to examine normative performance on the MoCA specific to community-dwelling African Americans. Findings suggest that certain aspects of this measure and previously established cutoff scores may not be well-suited for some populations.

Cognitive decline in metabolic syndrome is linked to microstructural white matter abnormalities

Subjects with metabolic syndrome (MetS) often show worse cognitive performance compared with the healthy population. We investigated whether microstructural white matter abnormalities are associated with cognitive performance in adults with MetS using diffusion tensor MR imaging. A total of 32 subjects with MetS (age 64.8 ± 7.8, 56.25 % female) and 23 age-, gender-, and education-matched healthy controls completed a battery of neuropsychological tests and diffusion tensor imaging (DTI) at 3-T MRI. Brain global and regional volumes, white matter fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD), and axial diffusivity (LD) were calculated. The least-square models adjusted for age, sex, HbA1c, hypertension, body mass index, hyperlipidemia, and white matter hyperintensities were used to evaluate the relationship between cognitive function and DTI. The MetS group had worse performance in verbal fluency (VF) and learning and memory function (total VF: T score (p = 0.01), VF: animals T score (p = 0.0001), Hopkins Verbal Learning Test (HVLT): Total recall T score (p = 0.0001), and HVLT: delayed recall T score (p = 0.002), as compared with controls. In the MetS group, abnormalities in diffusivity measures were associated with worse cognitive performance [VF: animals T score and left post-central gyrus-LD (p = 0.0007, r _adj 0.4), R angular gyrus-RD (p = 0.0008, r _adj 0.3), L supra-marginal gyrus-RD (p = 0.009, r _adj 0.2) after adjusting for age, sex, HbA1c, 24 h mean BP, presence of hyperlipidemia, and global white matter hyperintensities]. Microstructural white matter abnormalities in the MetS group might be the underlying mechanisms of worse verbal learning and memory performance.

Hippocampal Blood Flow Abnormality Associated With Depressive Symptoms and Cognitive Impairment in Patients With Chronic Heart Failure

BACKGROUND

Depressive symptoms and memory impairment are prevalent in patients with chronic heart failure (CHF). Although the mechanisms remain to be elucidated, the hippocampus (an important brain area for emotion and memory) may be a possible neural substrate for these symptoms.

METHODS AND RESULTS

We prospectively enrolled 40 Stage C patients, who had past or current CHF symptoms, and as controls 40 Stage B patients, who had structural heart disease but had never had CHF symptoms, in Brain Assessment and Investigation in Heart Failure Trial (B-HeFT) (UMIN000008584). As the primary index, we measured cerebral blood flow (CBF) in the 4 anterior-posterior segments of the hippocampus, using brain MRI analysis. Depressive symptoms, immediate memory (IM) and delayed memory (DM) were assessed using Geriatric Depression Scale (GDS), and Wechsler Memory Scale-revised (WMS-R), respectively. Hippocampus CBF in the most posterior segment was significantly lower in Stage C than in Stage B group (P=0.029 adjusted for Holm's method). Multiple regression analysis identified significant association between hippocampus CBF and GDS or DM score in Stage C group (all P<0.05). GDS score was significantly higher, and IM and DM scores were lower in Stage C patients with hippocampus CBF below the median than those with hippocampus CBF above the median (all P<0.05).

CONCLUSIONS

Hippocampus abnormalities are associated with depressive symptoms and cognitive impairment in CHF patients. (Circ J 2016; 80: 1773-1780).

Blood-Brain Barrier Leakage in Patients with Early Alzheimer Disease

Purpose To investigate whether the blood-brain barrier (BBB) leaks blood-circulating substances in patients with early forms of Alzheimer disease (AD), and if so, to examine the extent and pattern of leakage. Materials and Methods This study was approved by the local medical ethical committees of the Maastricht University Medical Center and Leiden University Medical Center, and written informed consent was obtained from all subjects. For this pilot study, 16 patients with early AD and 17 healthy age-matched control subjects underwent dynamic contrast material-enhanced magnetic resonance (MR) imaging sequence with dual time resolution for 25 minutes. The Patlak graphical approach was used to quantify the BBB leakage rate and local blood plasma volume. Subsequent histogram analysis was used to determine the volume fraction of the leaking brain tissue. Differences were assessed with linear regression analysis, adjusted for confounding variables. Results The BBB leakage rate was significantly higher in patients compared with that in control subjects in the total gray matter (P < .05) and cortex (P = .03). Patients had a significantly higher volume fraction of the leaking brain tissue in the gray matter (P = .004), normal-appearing white matter (P < .04), deep gray matter (P = .01), and cortex (P = .004). When all subjects were considered, scores on the Mini-Mental State Examination decreased significantly with increasing leakage in the deep gray matter (P = .007) and cortex (P < .05). Conclusion The results of this study showed global BBB leakage in patients with early AD that is associated with cognitive decline. A compromised BBB may be part of a cascade of pathologic events that eventually lead to cognitive decline and dementia. ^©RSNA, 2016 Online supplemental material is available for this article.