Pre-existing hypertension and the impact of stroke on cognitive function

Under pressure: the interplay of hypertension and white matter hyperintensities with cognition in chronic stroke aphasia

While converging research suggests that increased white matter hyperintensity load is associated with poorer cognition, and the presence of hypertension is associated with increased white matter hyperintensity load, the relationship among hypertension, cognition and white matter hyperintensities is not well understood. We sought to determine the effect of white matter hyperintensity burden on the relationship between hypertension and cognition in individuals with post-stroke aphasia, with the hypothesis that white matter hyperintensity load moderates the relationship between history of hypertension and cognitive function. Health history, Fazekas scores for white matter hyperintensities and Wechsler Adult Intelligence Scale Matrix Reasoning subtest scores for 79 people with aphasia collected as part of the Predicting Outcomes of Language Rehabilitation study at the Center for the Study of Aphasia Recovery at the University of South Carolina and the Medical University of South Carolina were analysed retrospectively. We found that participants with a history of hypertension had increased deep white matter hyperintensity severity (P < 0.001), but not periventricular white matter hyperintensity severity (P = 0.116). Moderation analysis revealed that deep white matter hyperintensity load moderates the relationship between high blood pressure and Wechsler Adult Intelligence Scale scores when controlling for age, education, aphasia severity and lesion volume. The interaction is significant, showing that a history of high blood pressure and severe deep white matter hyperintensities together are associated with poorer Matrix Reasoning scores. The overall model explains 41.85% of the overall variation in Matrix Reasoning score in this group of participants. These findings underscore the importance of considering cardiovascular risk factors in aphasia treatment, specifically hypertension and its relationship to brain health in post-stroke cognitive function.

Abdominal aortic calcification and risk of fracture among older women - The SOF study

Data concerning the link between severity of abdominal aortic calcification (AAC) and fracture risk in postmenopausal women are discordant. This association may vary by skeletal site and duration of follow-up. Our aim was to assess the association between the AAC severity and fracture risk in older women over the short- and long term. This is a case-cohort study nested in a large multicenter prospective cohort study. The association between AAC and fracture was assessed using Odds Ratios (OR) and 95% confidence intervals (95%CI) for vertebral fractures and using Hazard Risks (HR) and 95%CI for non-vertebral and hip fractures. AAC severity was evaluated from lateral spine radiographs using Kauppila's semiquantitative score. Severe AAC (AAC score 5+) was associated with higher risk of vertebral fracture during 4 years of follow-up, after adjustment for confounders (age, BMI, walking, smoking, hip bone mineral density, prevalent vertebral fracture, systolic blood pressure, hormone replacement therapy) (OR=2.31, 95%CI: 1.24-4.30, p<0.01). In a similar model, severe AAC was associated with an increase in the hip fracture risk (HR=2.88, 95%CI: 1.00-8.36, p=0.05). AAC was not associated with the risk of any non-vertebral fracture. AAC was not associated with the fracture risk after 15 years of follow-up. In elderly women, severe AAC is associated with higher short-term risk of vertebral and hip fractures, but not with the long-term risk of these fractures. There is no association between AAC and risk of non-vertebral-non-hip fracture in older women. Our findings lend further support to the hypothesis that AAC and skeletal fragility are related.

Mild cognitive decline. A position statement of the Cognitive Decline Group of the European Innovation Partnership for Active and Healthy Ageing (EIPAHA)

INTRODUCTION

Mild cognitive impairment (MCI) is a term used to describe a level of decline in cognition which is seen as an intermediate stage between normal ageing and dementia, and which many consider to be a prodromal stage of neurodegeneration that may become dementia. That is, it is perceived as a high risk level of cognitive change. The increasing burden of dementia in our society, but also our increasing understanding of its risk factors and potential interventions, require diligent management of MCI in order to find strategies that produce effective prevention of dementia.

AIM

To update knowledge regarding mild cognitive impairment, and to bring together and appraise evidence about the main features of clinical interest: definitions, prevalence and stability, risk factors, screening, and management and intervention.

METHODS

Literature review and consensus of expert opinion.

RESULTS AND CONCLUSION

MCI describes a level of impairment in which deteriorating cognitive functions still allow for reasonable independent living, including some compensatory strategies. While there is evidence for some early risk factors, there is still a need to more precisely delineate and distinguish early manifestations of frank dementia from cognitive impairment that is less likely to progress to dementia, and furthermore to develop improved prospective evidence for positive response to intervention. An important limitation derives from the scarcity of studies that take MCI as an endpoint. Strategies for effective management suffer from the same limitation, since most studies have focused on dementia. Behavioural changes may represent the most cost-effective approach.

Gout and the risk of dementia: a nationwide population-based cohort study

Introduction

Uric acid was proposed to have anti-oxidant property and possible neuroprotective effects. We examined the association between gout and dementia with population database.

Methods

The study utilized the claims data from the nationwide representative sample of Taiwan National Health Insurance Research Database (NHIRD). We ascertained patients with gout and dementia covering vascular and non-vascular (including Alzheimer’s) subtypes using International Classification of Diseases Ninth Revision, Clinical Modification (ICD9-CM) codes. A control group matched on sex, age, and index date of gout patients was randomly sampled with a ratio of 1:4 from the same database for comparison.

Results

From 2002 to 2008, 28,769 gout patients who were older than 50 years old were identified, and 114,742 control patients was matched into the study. During follow-up, 7,119 patients developed dementia (1,214 with gout, and 5,905 without gout). After adjusting for age, sex, and relevant comorbidities, a Cox regression analysis showed that gout patients had a lower risk of developing non-vascular dementia (hazard ratio (HR): 0.77; 95% confidence interval (CI): 0.72 - 0.83; p < 0.001) and vascular dementia (HR: 0.76; 95% CI: 0.65 - 0.88; p < 0.001).

Conclusions

Patients with gout have a lower risk of developing dementia. This phenomenon exists for both non-vascular and vascular types of dementia.

Risk factors for dementia in a senegalese elderly population aged 65 years and over

Background

With the aging of the population, dementia is increasing worldwide. The objective of this study was to identify risk factors for dementia in an elderly population utilizing a primary health care service in Dakar, Senegal.

Methods

Through a cross-sectional study conducted from March 2004 to December 31, 2005, 507 elderly patients aged ≥65 years who came to the Social and Medical Center of IPRES, Dakar, Senegal, were first screened with the screening interview questionnaire ‘Aging in Senegal’. Those who were cognitively impaired underwent a clinical examination to detect dementia. Univariate, bivariate, and multivariate logistic regression analyses were done.

Results

The whole population had a mean age of 72.4 years (±5.2) and was mostly male, married, and non-educated. Hypertension, arthritis, and gastrointestinal diseases were the main health conditions reported in the past medical history. Smoking was important while alcohol consumption was rare. Social network was high. Forty-five patients (8.87%) had dementia. In the multivariate model, only advanced age, education, epilepsy, and family history of dementia were independently associated with dementia.

Conclusion

The risk factors identified are also found in developed countries confirming their role in dementia. It is important to take dementia into consideration in Senegal and to sensitize the community for prevention.

Cognitive function and antihypertensive treatment in the elderly: a 6-year follow-up study

Both antihypertensive treatment and statins were proved to reduce mortality and morbidity from cardiovascular disease in the elderly. Yet their effect on cognitive functions of the elderly is unclear. In this study, 518 elderly were interviewed at their home six years ago. BP was measured and antihypertensive drug treatment and cognitive functions were evaluated. 318 of the original sample were re-examined (81% of the survivors). We evaluated the selective survival in relation to changes in BP, the specific drug usage and cognitive functioning. Beta blocker treatment increased the odds of survival but also the odds of decline in MMSE and memory scores. ACE-I treatment was also associated with decline in memory. Subjects treated with CCB had improved MMSE scores, memory, and performed better on tasks requiring concentration. Statins treatment in this study did not show any affect on cognitive functions. Although most subjects were treated by more than one antihypertensive drug, less than half were normalized at baseline and only one quarter at follow-up. Despite the low normalization rate, antihypertensive treatment regimen had been hardly changed during the six years follow-up. The use of statins, however, increased dramatically: from 6% at baseline to almost half at follow-up. According to our findings CCB emerges as the best option for reducing BP in elderly patients. It appeared to improve cognitive functions without hampering survival.

Atrial fibrillation is independently associated with senile, vascular, and Alzheimer's dementia

BACKGROUND

The aging population has resulted in more patients living with cardiovascular disease, such as atrial fibrillation (AF). Recent focus has been placed on understanding the long-term consequences of chronic cardiovascular disease, such as a potential increased risk of dementia.

OBJECTIVE

This study sought to determine whether there is an association between AF and dementia and whether their coexistence is an independent marker of risk.

METHODS

A total of 37,025 consecutive patients from the large ongoing prospective Intermountain Heart Collaborative Study database were evaluated and followed up for a mean of 5 years for the development of AF and dementia. Dementia was sub-typed into vascular (VD), senile (SD), Alzheimer's (AD), and nonspecified (ND).

RESULTS

Of the 37,025 patients with a mean age of 60.6 +/- 17.9 years, 10,161 (27%) developed AF and 1,535 (4.1%) developed dementia (179 VD, 321 SD, 347 AD, 688 ND) during the 5-year follow-up. Patients with dementia were older and had higher rates of hypertension, coronary artery disease, renal failure, heart failure, and prior strokes. In age-based analysis, AF independently was significantly associated with all dementia types. The highest risk was in the younger group (<70). After dementia diagnosis, the presence of AF was associated with a marked increased risk of mortality (VD: hazard ratio [HR] = 1.38, P = .01; SD: HR = 1.41, P = .001; AD: HR = 1.45; ND: HR = 1.38, P <.0001).

CONCLUSION

AF was independently associated with all forms of dementia. Although dementia is strongly associated with aging, the highest risk of AD was in the younger group, in support of the observed association. The presence of AF also identified dementia patients at high risk of death.

Hypertension increases the probability of Alzheimer's disease and of mild cognitive impairment in an Arab community in northern Israel

BACKGROUND

We aimed to determine whether vascular risk factors are associated with Alzheimer's disease (AD) and mild cognitive impairment (MCI) in an elderly Arab population.

METHODS

An Arabic-speaking team performed a door-to-door survey of consecutive residents aged > or =65 years. We estimated the odds of AD or MCI versus normal controls as a function of age, gender, education and presence of vascular factors by multinomial logistic regression with interactions.

RESULTS

Out of 767 subjects (54% men), 444 were cognitively normal, 234 had MCI and 89 had AD. AD was significantly associated with hypertension (p = 0.01; OR = 2.08; 95% CI: 1.18-3.65), age (p < 0.0001; OR = 1.19; 95% CI: 1.14-1.24), female gender (p = 0.0016; OR = 3.06; 95% CI: 1.53-6.15) and education (p = 0.0002; OR = 0.75; 95% CI: 0.65-0.88). MCI was significantly associated with hypertension (p = 0.0042; OR = 1.69; 95% CI: 1.25-2.44), age (p < 0.0001; OR = 1.06; 95% CI: 1.03-1.09) and education (p < 0.0001; OR = 0.76; 95% CI: 0.71-0.83), but not with gender.

CONCLUSIONS

Hypertension, older age and low education significantly increase the probability of AD and MCI. The effect of hypertension on the odds of AD versus controls is over and above the effects of age, gender and education. For MCI versus controls there is no gender effect, and the effect of hypertension is over and above the effects of age and education.

Executive function, more than global cognition, predicts functional decline and mortality in elderly women

BACKGROUND

Functional impairment in community-dwelling older adults is common and is associated with poor outcomes. Our goal was to compare the contribution of impairment in executive function or global cognitive function to predicting functional decline and mortality.

METHODS

We studied 7717 elderly women enrolled in a prospective study (mean age 73.3 years) and identified women with poor baseline executive function (score > 1 standard deviation [SD] below the mean on the Trail Making Test B (Trails B; n = 957, 12.4%), poor global cognitive function (score > 1 SD below the mean on a modified Mini-Mental State Examination [mMMSE], n = 387, 5.0%), impairment in both (n = 249, 3.2%), or no impairment (n = 6124, 79.4%). We compared level of functional difficulty (Activities of Daily Living [ADLs] and Instrumental ADLs [IADLs]) at baseline and at 6-year follow-up and survival at follow-up. We also determined if the association was independent of age, education, depression, medical comorbidities, and baseline functional ability.

RESULTS

At baseline, women with Trails B impairment only or impairment on both tests reported the highest proportion of ADL and IADL dependence compared to the other groups. At the 6-year follow-up after adjusting for age, education, medical comorbidities, depression, and baseline ADL or IADL, women with only Trails B impairment were 1.3 times more likely to develop an incident ADL dependence (adjusted odds ratio [OR] = 1.34; 95% confidence interval [CI], 1.07-1.69) and 1.5 times more likely to develop a worsening of ADL dependence (adjusted OR = 1.48; 95% CI, 1.16-1.89) when compared to women with no impairment on either test. In addition, women with only Trails B impairment had a 1.5-fold increased risk of mortality (adjusted hazard ratio [HR] = 1.48; 95% CI, 1.21-1.81). In contrast, women with impairment on only mMMSE were not at increased risk to develop incident ADL or IADL dependence, a worsening of ADL or IADL dependence, or mortality.

CONCLUSION

Compared to women with no impairment, women with executive function impairment had significantly worse ADL and IADL function cross-sectionally and over 6 years. Individuals with executive dysfunction also had increased risk of mortality. These results suggest that screening of executive function can help to identify women who are at risk for functional decline and decreased survival.

Cardiovascular diseases and decline in cognitive function in an elderly community population: the Edinburgh Artery Study

OBJECTIVE

To investigate cognitive performance and 4-year change in cognitive function in relation to different clinical manifestations of atherosclerotic disease in an elderly community population.

METHODS

The Edinburgh Artery Study is a population cohort study of men and women who were recruited to a baseline survey in 1987 and 1988. From the time of study entry, the participants have been invited to two follow-up clinical examinations and continuously monitored for major fatal and nonfatal vascular events. All alive and eligible subjects were invited for cognitive testing in two study years when the mean age of the sample was 73.1 (standard deviation = 5.0) years. A follow-up cognitive assessment was performed in 2002 and 2003 on 452 survivors.

RESULTS

In multivariate analyses controlling for demographic characteristics, depression, and major atherosclerotic risk factors, stroke was associated with a significantly worse performance on tests of verbal memory (p = .02) and letter fluency (p = .002). In addition, stroke was related to a significantly steeper 4-year decline in verbal memory performance (p = .04). Among the subjects who had not had an overt stroke, those with symptomatic peripheral arterial disease experienced a significantly greater 4-year decline in verbal memory functioning (p = .04).

CONCLUSIONS

In older people, stroke is associated with both worse performance on cognitive tests and progressive verbal memory decline. Elderly individuals with vascular diseases other than stroke may also be vulnerable to a greater decline in verbal memory function. A relationship between vascular diseases and verbal memory decline may exist independently of depressed mood and major atherosclerotic risk factors.

Blood Pressure Treatment and Cognition in the Elderly

While the health and longevity benefits of antihypertensive treatment have been established in past research, the cognitive consequences of blood pressure control in the elderly are still under debate. In this paper, the authors review the current evidence and the different ways in which cognition is measured. Since research on the cognitive consequences of blood pressure control in the elderly population is characterized by a variety of research questions, designs, and cognitive measurements, the authors conclude that a large-scale study that compares the cognitive benefits of different methods of blood pressure reduction is urgently needed.

Focal Wallerian degeneration of the corpus callosum in large middle cerebral artery stroke: Serial diffusion tensor imaging

PURPOSE

To detect lesion-related focal Wallerian degeneration (WD) changes in different segments of the corpus callosum (CC) in patients with large middle cerebral arterial (MCA) territory stroke using diffusion tensor imaging (DTI).

MATERIALS AND METHODS

Eight patients underwent DTI scans at three different time points: six to eight weeks, 10-12 weeks, and beyond six months of stroke onset. Eight healthy age-matched controls were also scanned using the same protocol at three different time points. Region-of-interest (ROI) analysis was performed on seven segments of the CC to determine the fractional anisotropy (FA), mean diffusivity (MD), and corresponding callosal cross-sectional areas.

RESULTS

On repeated-measures analysis of variance (ANOVA), a significant reduction in the FA values was observed from the first to the third study compared to controls, reflecting temporal degeneration in the rostrum, genu, rostral body, anterior midbody, and splenium of the CC. However, a significant temporal elevation in MD values was observed in only the rostral body and anterior midbody of the CC. This was associated with a significant region-specific reduction in the cross-sectional areas at time points beyond six months, and appears to be consistent with the loss of callosal structural components due to interruption of the cortico-callosal fibers secondary to WD.

CONCLUSION

These results indicate that cortico-callosal topographical changes exhibit a significant temporal decline in observed FA values that is suggestive of cortico-callosal WD in patients with large MCA territory stroke.