Cerebrovascular Disorders
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Publication
Journal: New England Journal of Medicine
December/18/1995
Abstract
Thrombolytic therapy for acute ischemic stroke has been approached cautiously because there were high rates of intracerebral hemorrhage in early clinical trials. We performed a randomized, double-blind trial of intravenous recombinant tissue plasminogen activator (t-PA) for ischemic stroke after recent pilot studies suggested that t-PA was beneficial when treatment was begun within three hours of the onset of stroke.
The trial had two parts. Part 1 (in which 291 patients were enrolled) tested whether t-PA had clinical activity, as indicated by an improvement of 4 points over base-line values in the score of the National Institutes of Health stroke scale (NIHSS) or the resolution of the neurologic deficit within 24 hours of the onset of stroke. Part 2 (in which 333 patients were enrolled) used a global test statistic to assess clinical outcome at three months, according to scores on the Barthel index, modified Rankin scale, Glasgow outcome scale, and NIHSS:
In part 1, there was no significant difference between the group given t-PA and that given placebo in the percentages of patients with neurologic improvement at 24 hours, although a benefit was observed for the t-PA group at three months for all four outcome measures. In part 2, the long-term clinical benefit of t-PA predicted by the results of part 1 was confirmed (global odds ratio for a favorable outcome, 1.7; 95 percent confidence interval, 1.2 to 2.6). As compared with patients given placebo, patients treated with t-PA were at least 30 percent more likely to have minimal or no disability at three months on the assessment scales. Symptomatic intracerebral hemorrhage within 36 hours after the onset of stroke occurred in 6.4 percent of patients given t-PA but only 0.6 percent of patients given placebo (P < 0.001). Mortality at three months was 17 percent in the t-PA group and 21 percent in the placebo group (P = 0.30).
Despite an increased incidence of symptomatic intracerebral hemorrhage, treatment with intravenous t-PA within three hours of the onset of ischemic stroke improved clinical outcome at three months.
Publication
Journal: BMJ (Clinical research ed.)
October/27/1998
Abstract
OBJECTIVE
To determine whether tight control of blood pressure prevents macrovascular and microvascular complications in patients with type 2 diabetes.
METHODS
Randomised controlled trial comparing tight control of blood pressure aiming at a blood pressure of <150/85 mm Hg (with the use of an angiotensin converting enzyme inhibitor captopril or a beta blocker atenolol as main treatment) with less tight control aiming at a blood pressure of <180/105 mm Hg.
METHODS
20 hospital based clinics in England, Scotland, and Northern Ireland.
METHODS
1148 hypertensive patients with type 2 diabetes (mean age 56, mean blood pressure at entry 160/94 mm Hg); 758 patients were allocated to tight control of blood pressure and 390 patients to less tight control with a median follow up of 8.4 years.
METHODS
Predefined clinical end points, fatal and non-fatal, related to diabetes, deaths related to diabetes, and all cause mortality. Surrogate measures of microvascular disease included urinary albumin excretion and retinal photography.
RESULTS
Mean blood pressure during follow up was significantly reduced in the group assigned tight blood pressure control (144/82 mm Hg) compared with the group assigned to less tight control (154/87 mm Hg) (P<0.0001). Reductions in risk in the group assigned to tight control compared with that assigned to less tight control were 24% in diabetes related end points (95% confidence interval 8% to 38%) (P=0.0046), 32% in deaths related to diabetes (6% to 51%) (P=0.019), 44% in strokes (11% to 65%) (P=0.013), and 37% in microvascular end points (11% to 56%) (P=0.0092), predominantly owing to a reduced risk of retinal photocoagulation. There was a non-significant reduction in all cause mortality. After nine years of follow up the group assigned to tight blood pressure control also had a 34% reduction in risk in the proportion of patients with deterioration of retinopathy by two steps (99% confidence interval 11% to 50%) (P=0.0004) and a 47% reduced risk (7% to 70%) (P=0.004) of deterioration in visual acuity by three lines of the early treatment of diabetic retinopathy study (ETDRS) chart. After nine years of follow up 29% of patients in the group assigned to tight control required three or more treatments to lower blood pressure to achieve target blood pressures.
CONCLUSIONS
Tight blood pressure control in patients with hypertension and type 2 diabetes achieves a clinically important reduction in the risk of deaths related to diabetes, complications related to diabetes, progression of diabetic retinopathy, and deterioration in visual acuity.
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Publication
Journal: Stroke
September/11/1991
Abstract
The impact of nonrheumatic atrial fibrillation, hypertension, coronary heart disease, and cardiac failure on stroke incidence was examined in 5,070 participants in the Framingham Study after 34 years of follow-up. Compared with subjects free of these conditions, the age-adjusted incidence of stroke was more than doubled in the presence of coronary heart disease (p less than 0.001) and more than trebled in the presence of hypertension (p less than 0.001). There was a more than fourfold excess of stroke in subjects with cardiac failure (p less than 0.001) and a near fivefold excess when atrial fibrillation was present (p less than 0.001). In persons with coronary heart disease or cardiac failure, atrial fibrillation doubled the stroke risk in men and trebled the risk in women. With increasing age the effects of hypertension, coronary heart disease, and cardiac failure on the risk of stroke became progressively weaker (p less than 0.05). Advancing age, however, did not reduce the significant impact of atrial fibrillation. For persons aged 80-89 years, atrial fibrillation was the sole cardiovascular condition to exert an independent effect on stroke incidence (p less than 0.001). The attributable risk of stroke for all cardiovascular contributors decreased with age except for atrial fibrillation, for which the attributable risk increased significantly (p less than 0.01), rising from 1.5% for those aged 50-59 years to 23.5% for those aged 80-89 years. While these findings highlight the impact of each cardiovascular condition on the risk of stroke, the data suggest that the elderly are particularly vulnerable to stroke when atrial fibrillation is present.(ABSTRACT TRUNCATED AT 250 WORDS)
Publication
Journal: JAMA Neurology
April/10/2020
Abstract
The outbreak of coronavirus disease 2019 (COVID-19) in Wuhan, China, is serious and has the potential to become an epidemic worldwide. Several studies have described typical clinical manifestations including fever, cough, diarrhea, and fatigue. However, to our knowledge, it has not been reported that patients with COVID-19 had any neurologic manifestations.To study the neurologic manifestations of patients with COVID-19.This is a retrospective, observational case series. Data were collected from January 16, 2020, to February 19, 2020, at 3 designated special care centers for COVID-19 (Main District, West Branch, and Tumor Center) of the Union Hospital of Huazhong University of Science and Technology in Wuhan, China. The study included 214 consecutive hospitalized patients with laboratory-confirmed diagnosis of severe acute respiratory syndrome coronavirus 2 infection.Clinical data were extracted from electronic medical records, and data of all neurologic symptoms were checked by 2 trained neurologists. Neurologic manifestations fell into 3 categories: central nervous system manifestations (dizziness, headache, impaired consciousness, acute cerebrovascular disease, ataxia, and seizure), peripheral nervous system manifestations (taste impairment, smell impairment, vision impairment, and nerve pain), and skeletal muscular injury manifestations.Of 214 patients (mean [SD] age, 52.7 [15.5] years; 87 men [40.7%]) with COVID-19, 126 patients (58.9%) had nonsevere infection and 88 patients (41.1%) had severe infection according to their respiratory status. Overall, 78 patients (36.4%) had neurologic manifestations. Compared with patients with nonsevere infection, patients with severe infection were older, had more underlying disorders, especially hypertension, and showed fewer typical symptoms of COVID-19, such as fever and cough. Patients with more severe infection had neurologic manifestations, such as acute cerebrovascular diseases (5 [5.7%] vs 1 [0.8%]), impaired consciousness (13 [14.8%] vs 3 [2.4%]), and skeletal muscle injury (17 [19.3%] vs 6 [4.8%]).Patients with COVID-19 commonly have neurologic manifestations. During the epidemic period of COVID-19, when seeing patients with neurologic manifestations, clinicians should suspect severe acute respiratory syndrome coronavirus 2 infection as a differential diagnosis to avoid delayed diagnosis or misdiagnosis and lose the chance to treat and prevent further transmission.
Publication
Journal: Stroke
June/7/1988
Abstract
Interobserver agreement for the assessment of handicap in stroke patients was investigated in a group of 10 senior neurologists and 24 residents from two centers. One hundred patients were separately interviewed by two physicians in different combinations. The degree of handicap was recorded by each observer on the modified Rankin scale, which has six grades (0-5). The agreement rates were corrected for chance (kappa statistics). Both physicians agreed on the degree of handicap in 65 patients; they differed by one grade in 32 patients and by two grades in 3 patients. Kappa for all pairwise observations was 0.56; the value for weighted kappa (with quadratic disagreement weights) was 0.91. Our results confirm the value of the modified Rankin scale in the assessment of handicap in stroke patients; nevertheless, further improvements are possible.
Publication
Journal: Annals of Epidemiology
February/2/1994
Abstract
The Cardiovascular Health Study (CHS) is a population-based, longitudinal study of coronary heart disease and stroke in adults aged 65 years and older. The main objective of the study is to identify factors related to the onset and course of coronary heart disease and stroke. CHS is designed to determine the importance of conventional cardiovascular disease (CVD) risk factors in older adults, and to identify new risk factors in this age group, especially those that may be protective and modifiable. The study design called for enrollment of 1250 men and women in each of four communities: Forsyth County, North Carolina; Sacramento County, California; Washington County, Maryland; and Pittsburgh, Pennsylvania. Eligible participants were sampled from Medicare eligibility lists in each area. Extensive physical and laboratory evaluations were performed at baseline to identify the presence and severity of CVD risk factors such as hypertension, hypercholesterolemia and glucose intolerance; subclinical disease such as carotid artery atherosclerosis, left ventricular enlargement, and transient ischemia; and clinically overt CVD. These examinations in CHS permit evaluation of CVD risk factors in older adults, particularly in groups previously under-represented in epidemiologic studies, such as women and the very old. The first of two examination cycles began in June 1989. A second comprehensive examination will be repeated three years later. Periodic interim contacts are scheduled to ascertain and verify the incidence of CVD events, the frequency of recurrent events, and the sequellae of CVD.
Publication
Journal: Trends in Neurosciences
September/13/1999
Abstract
Brain injury following transient or permanent focal cerebral ischaemia (stroke) develops from a complex series of pathophysiological events that evolve in time and space. In this article, the relevance of excitotoxicity, peri-infarct depolarizations, inflammation and apoptosis to delayed mechanisms of damage within the peri-infarct zone or ischaemic penumbra are discussed. While focusing on potentially new avenues of treatment, the issue of why many clinical stroke trials have so far proved disappointing is addressed. This article provides a framework that can be used to generate testable hypotheses and treatment strategies that are linked to the appearance of specific pathophysiological events within the ischaemic brain.
Publication
Journal: New England Journal of Medicine
August/15/1991
Abstract
Without strong evidence of benefit, the use of carotid endarterectomy for prophylaxis against stroke rose dramatically until the mid-1980s, then declined. Our investigation sought to determine whether carotid endarterectomy reduces the risk of stroke among patients with a recent adverse cerebrovascular event and ipsilateral carotid stenosis.
We conducted a randomized trial at 50 clinical centers throughout the United States and Canada, in patients in two predetermined strata based on the severity of carotid stenosis--30 to 69 percent and 70 to 99 percent. We report here the results in the 659 patients in the latter stratum, who had had a hemispheric or retinal transient ischemic attack or a nondisabling stroke within the 120 days before entry and had stenosis of 70 to 99 percent in the symptomatic carotid artery. All patients received optimal medical care, including antiplatelet therapy. Those assigned to surgical treatment underwent carotid endarterectomy performed by neurosurgeons or vascular surgeons. All patients were examined by neurologists 1, 3, 6, 9, and 12 months after entry and then every 4 months. End points were assessed by blinded, independent case review. No patient was lost to follow-up.
Life-table estimates of the cumulative risk of any ipsilateral stroke at two years were 26 percent in the 331 medical patients and 9 percent in the 328 surgical patients--an absolute risk reduction (+/- SE) 17 +/- 3.5 percent (P less than 0.001). For a major or fatal ipsilateral stroke, the corresponding estimates were 13.1 percent and 2.5 percent--an absolute risk reduction of 10.6 +/- 2.6 percent (P less than 0.001). Carotid endarterectomy was still found to be beneficial when all strokes and deaths were included in the analysis (P less than 0.001).
Carotid endarterectomy is highly beneficial to patients with recent hemispheric and retinal transient ischemic attacks or nondisabling strokes and ipsilateral high-grade stenosis (70 to 99 percent) of the internal carotid artery.
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Publication
Journal: European Heart Journal
March/9/2014
Publication
Journal: New England Journal of Medicine
January/6/1999
Abstract
BACKGROUND
The combined thickness of the intima and media of the carotid artery is associated with the prevalence of cardiovascular disease. We studied the associations between the thickness of the carotid-artery intima and media and the incidence of new myocardial infarction or stroke in persons without clinical cardiovascular disease.
METHODS
Noninvasive measurements of the intima and media of the common and internal carotid artery were made with high-resolution ultrasonography in 5858 subjects 65 years of age or older. Cardiovascular events (new myocardial infarction or stroke) served as outcome variables in subjects without clinical cardiovascular disease (4476 subjects) over a median follow-up period of 6.2 years.
RESULTS
The incidence of cardiovascular events correlated with measurements of carotid-artery intima-media thickness. The relative risk of myocardial infarction or stroke increased with intima-media thickness (P<0.001). The relative risk of myocardial infarction or stroke (adjusted for age and sex) for the quintile with the highest thickness as compared with the lowest quintile was 3.87 (95 percent confidence interval, 2.72 to 5.51). The association between cardiovascular events and intima-media thickness remained significant after adjustment for traditional risk factors, showing increasing risks for each quintile of combined intima-media thickness, from the second quintile (relative risk, 1.54; 95 percent confidence interval, 1.04 to 2.28), to the third (relative risk, 1.84; 95 percent confidence interval, 1.26 to 2.67), fourth (relative risk, 2.01; 95 percent confidence interval, 1.38 to 2.91), and fifth (relative risk, 3.15; 95 percent confidence interval, 2.19 to 4.52). The results of separate analyses of myocardial infarction and stroke paralleled those for the combined end point.
CONCLUSIONS
Increases in the thickness of the intima and media of the carotid artery, as measured noninvasively by ultrasonography, are directly associated with an increased risk of myocardial infarction and stroke in older adults without a history of cardiovascular disease.
Publication
Journal: Stroke
August/17/1989
Abstract
We designed a 15-item neurologic examination stroke scale for use in acute stroke therapy trials. In a study of 24 stroke patients, interrater reliability for the scale was found to be high (mean kappa = 0.69), and test-retest reliability was also high (mean kappa = 0.66-0.77). Test-retest reliability did not differ significantly among a neurologist, a neurology house officer, a neurology nurse, or an emergency department nurse. The stroke scale validity was assessed by comparing the scale scores obtained prospectively on 65 acute stroke patients to the patients' infarction size as measured by computed tomography scan at 1 week and to the patients' clinical outcome as determined at 3 months. These correlations (scale-lesion size r = 0.68, scale-outcome r = 0.79) suggested acceptable examination and scale validity. Of the 15 test items, the most interrater reliable item (pupillary response) had low validity. Less reliable items such as upper or lower extremity motor function were more valid. We discuss methods for improving the reliability and validity of brief examination scales to be used in stroke therapy trials.
Publication
Journal: Scandinavian journal of rehabilitation medicine
September/4/1975
Abstract
A system for evaluation of motor function, balance, some sensation qualities and joint function in hemiplegic patients is described in detail. The system applies a cumulative numerical score. A series of hemiplegic patients has been followed from within one week post-stroke and throughout one year. When initially nearly flaccid hemiparalysis prevails, the motor recovery, if any occur, follows a definable course. The findings in this study substantiate the validity of ontogenetic principles as applicable to the assessment of motor behaviour in hemiplegic patients, and foocus the importance of early therapeutic measures against contractures.
Publication
Journal: Circulation
September/24/1998
Abstract
BACKGROUND
Atrial fibrillation (AF) causes substantial morbidity. It is uncertain whether AF is associated with excess mortality independent of associated cardiac conditions and risk factors.
RESULTS
We examined the mortality of subjects 55 to 94 years of age who developed AF during 40 years of follow-up of the original Framingham Heart Study cohort. Of the original 5209 subjects, 296 men and 325 women (mean ages, 74 and 76 years, respectively) developed AF and met eligibility criteria. By pooled logistic regression, after adjustment for age, hypertension, smoking, diabetes, left ventricular hypertrophy, myocardial infarction, congestive heart failure, valvular heart disease, and stroke or transient ischemic attack, AF was associated with an OR for death of 1.5 (95% CI, 1.2 to 1.8) in men and 1.9 (95% CI, 1.5 to 2.2) in women. The risk of mortality conferred by AF did not significantly vary by age. However, there was a significant AF-sex interaction: AF diminished the female advantage in survival. In secondary multivariate analyses, in subjects free of valvular heart disease and preexisting cardiovascular disease, AF remained significantly associated with excess mortality, with about a doubling of mortality in both sexes.
CONCLUSIONS
In subjects from the original cohort of the Framingham Heart Study, AF was associated with a 1.5- to 1.9-fold mortality risk after adjustment for the preexisting cardiovascular conditions with which AF was related. The decreased survival seen with AF was present in men and women and across a wide range of ages.
Publication
Journal: The Lancet
May/21/1997
Abstract
BACKGROUND
Reliable information on causes of death is essential to the development of national and international health policies for prevention and control of disease and injury. Medically certified information is available for less than 30% of the estimated 50.5 million deaths that occur each year worldwide. However, other data sources can be used to develop cause-of-death estimates for populations. To be useful, estimates must be internally consistent, plausible, and reflect epidemiological characteristics suggested by community-level data. The Global Burden of Disease Study (GBD) used various data sources and made corrections for miscoding of important diseases (eg, ischaemic heart disease) to estimate worldwide and regional cause-of-death.patterns in 1990 for 14 age-sex groups in eight regions, for 107 causes.
METHODS
Preliminary estimates were developed with available vital-registration data, sample-registration data for India and China, and small-scale population-study data sources. Registration data were corrected for miscoding, and Lorenz-curve analysis was used to estimate cause-of-death patterns in areas without registration. Preliminary estimates were modified to reflect the epidemiology of selected diseases and injuries. Final estimates were checked to ensure that numbers of deaths in specific age-sex groups did not exceed estimates suggested by independent demographic methods.
RESULTS
98% of all deaths in children younger than 15 years are in the developing world. 83% and 59% of deaths at 15-59 and 70 years, respectively, are in the developing world. The probability of death between birth and 15 years ranges from 22.0% in sub-Saharan Africa to 1.1% in the established market economies. Probabilities of death between 15 and 60 years range from 7.2% for women in established market economies to 39.1% for men in sub-Saharan Africa. The probability of a man or woman dying from a non-communicable disease is higher in sub-Saharan Africa and other developing regions than in established market economies. Worldwide in 1990, communicable, maternal, perinatal, and nutritional disorders accounted for 17.2 million deaths, non-communicable diseases for 28.1 million deaths and injuries for 5.1 million deaths. The leading causes of death in 1990 were ischaemic heart disease (6.3 million deaths), cerebrovascular accidents (4.4 million deaths), lower respiratory infections (4.3 million), diarrhoeal diseases (2.9 million), perinatal disorders (2.4 million), chronic obstructive pulmonary disease (2.2 million), tuberculosis (2.0 million), measles (1.1 million), road-traffic accidents (1.0 million), and lung cancer (0.9 million).
CONCLUSIONS
Five of the ten leading killers are communicable, perinatal, and nutritional disorders largely affecting children. Non-communicable diseases are, however, already major public health challenges in all regions. Injuries, which account for 10% of global mortality, are often ignored as a major cause of death and may require innovative strategies to reduce their toll. The estimates by cause have wide Cls, but provide a foundation for a more informed debate on public-health priorities.
Publication
Journal: JAMA - Journal of the American Medical Association
July/14/1991
Abstract
OBJECTIVE
To assess the ability of antihypertensive drug treatment to reduce the risk of nonfatal and fatal (total) stroke in isolated systolic hypertension.
METHODS
Multicenter, randomized, double-blind, placebo-controlled.
METHODS
Community-based ambulatory population in tertiary care centers.
METHODS
4736 persons (1.06%) from 447,921 screenees aged 60 years and above were randomized (2365 to active treatment, 2371 to placebo). Systolic blood pressure ranged from 160 to 219 mm Hg and diastolic blood pressure was less than 90 mm Hg. Of the participants, 3161 were not receiving antihypertensive medication at initial contact, and 1575 were. The average systolic blood pressure was 170 mm Hg; average diastolic blood pressure, 77 mm Hg. The mean age was 72 years, 57% were women, and 14% were black.
METHODS
--Participants were stratified by clinical center and by antihypertensive medication status at initial contact. For step 1 of the trial, dose 1 was chlorthalidone, 12.5 mg/d, or matching placebo; dose 2 was 25 mg/d. For step 2, dose 1 was atenolol, 25 mg/d, or matching placebo; dose 2 was 50 mg/d.
METHODS
Primary. Nonfatal and fatal (total) stroke. Secondary. Cardiovascular and coronary morbidity and mortality, all-cause mortality, and quality of life measures.
RESULTS
Average follow-up was 4.5 years. The 5-year average systolic blood pressure was 155 mm Hg for the placebo group and 143 mm Hg for the active treatment group, and the 5-year average diastolic blood pressure was 72 and 68 mm Hg, respectively. The 5-year incidence of total stroke was 5.2 per 100 participants for active treatment and 8.2 per 100 for placebo. The relative risk by proportional hazards regression analysis was 0.64 (P = .0003). For the secondary end point of clinical nonfatal myocardial infarction plus coronary death, the relative risk was 0.73. Major cardiovascular events were reduced (relative risk, 0.68). For deaths from all causes, the relative risk was 0.87.
CONCLUSIONS
In persons aged 60 years and over with isolated systolic hypertension, antihypertensive stepped-care drug treatment with low-dose chlorthalidone as step 1 medication reduced the incidence of total stroke by 36%, with 5-year absolute benefit of 30 events per 1000 participants. Major cardiovascular events were reduced, with 5-year absolute benefit of 55 events per 1000.
Publication
Journal: The Lancet
April/29/1990
Abstract
The associations of diastolic blood pressure (DBP) with stroke and with coronary heart disease (CHD) were investigated in nine major prospective observational studies: total 420,000 individuals, 843 strokes, and 4856 CHD events, 6-25 (mean 10) years of follow-up. The combined results demonstrate positive, continuous, and apparently independent associations, with no significant heterogeneity of effect among different studies. Within the range of DBP studied (about 70-110 mm Hg), there was no evidence of any "threshold" below which lower levels of DBP were not associated with lower risks of stroke and of CHD. Previous analyses have described the uncorrected associations of DBP measured just at "baseline" with subsequent disease rates. But, because of the diluting effects of random fluctuations in DBP, these substantially underestimate the true associations of the usual DBP (ie, an individual's long-term average DBP) with disease. After correction for this "regression dilution" bias, prolonged differences in usual DBP of 5, 7.5, and 10 mm Hg were respectively associated with at least 34%, 46%, and 56% less stroke and at least 21%, 29%, and 37% less CHD. These associations are about 60% greater than in previous uncorrected analyses. (This regression dilution bias is quite general, so analogous corrections to the relations of cholesterol to CHD or of various other risk factors to CHD or to other diseases would likewise increase their estimated strengths.) The DBP results suggest that for the large majority of individuals, whether conventionally "hypertensive" or "normotensive", a lower blood pressure should eventually confer a lower risk of vascular disease.
Publication
Journal: Pharmacological Reviews
August/7/2005
Abstract
The blood-brain barrier (BBB) is the regulated interface between the peripheral circulation and the central nervous system (CNS). Although originally observed by Paul Ehrlich in 1885, the nature of the BBB was debated well into the 20th century. The anatomical substrate of the BBB is the cerebral microvascular endothelium, which, together with astrocytes, pericytes, neurons, and the extracellular matrix, constitute a "neurovascular unit" that is essential for the health and function of the CNS. Tight junctions (TJ) between endothelial cells of the BBB restrict paracellular diffusion of water-soluble substances from blood to brain. The TJ is an intricate complex of transmembrane (junctional adhesion molecule-1, occludin, and claudins) and cytoplasmic (zonula occludens-1 and -2, cingulin, AF-6, and 7H6) proteins linked to the actin cytoskeleton. The expression and subcellular localization of TJ proteins are modulated by several intrinsic signaling pathways, including those involving calcium, phosphorylation, and G-proteins. Disruption of BBB TJ by disease or drugs can lead to impaired BBB function and thus compromise the CNS. Therefore, understanding how BBB TJ might be affected by various factors holds significant promise for the prevention and treatment of neurological diseases.
Publication
Journal: Brain
May/21/1998
Abstract
Anatomical, physiological and functional neuroimaging studies suggest that the cerebellum participates in the organization of higher order function, but there are very few descriptions of clinically relevant cases that address this possibility. We performed neurological examinations, bedside mental state tests, neuropsychological studies and anatomical neuroimaging on 20 patients with diseases confined to the cerebellum, and evaluated the nature and severity of the changes in neurological and mental function. Behavioural changes were clinically prominent in patients with lesions involving the posterior lobe of the cerebellum and the vermis, and in some cases they were the most noticeable aspects of the presentation. These changes were characterized by: impairment of executive functions such as planning, set-shifting, verbal fluency, abstract reasoning and working memory; difficulties with spatial cognition including visual-spatial organization and memory; personality change with blunting of affect or disinhibited and inappropriate behaviour; and language deficits including agrammatism and dysprosodia. Lesions of the anterior lobe of the cerebellum produced only minor changes in executive and visual-spatial functions. We have called this newly defined clinical entity the 'cerebellar cognitive affective syndrome'. The constellation of deficits is suggestive of disruption of the cerebellar modulation of neural circuits that link prefrontal, posterior parietal, superior temporal and limbic cortices with the cerebellum.
Publication
Journal: The Lancet
May/9/1990
Abstract
There are 14 unconfounded randomised trials of antihypertensive drugs (chiefly diuretics or beta-blockers): total 37,000 individuals, mean treatment duration 5 years, mean diastolic blood pressure (DBP) difference 5-6 mm Hg. In prospective observational studies, a long-term difference of 5-6 mm Hg in usual DBP is associated with about 35-40% less stroke and 20-25% less coronary heart disease (CHD). For those dying in the trials, the DBP difference had persisted only 2-3 years, yet an overview showed that vascular mortality was significantly reduced (2p less than 0.0002); non-vascular mortality appeared unchanged. Stroke was reduced by 42% SD 6 (95% confidence interval 35-50%; 289 vs 484 events, 2p less than 0.0001), suggesting that virtually all the epidemiologically expected stroke reduction appears rapidly. CHD was reduced by 14% SD 5 (95% CI 4-22%; 671 vs 771 events, 2p less than 0.01), suggesting that just over half the epidemiologically expected CHD reduction appears rapidly. Although this significant CHD reduction could well be worthwhile, its size remains indefinite for most circumstances (though beta-blockers after myocardial infarction are of substantial benefit). At present, therefore, a sufficiently high risk of stroke (perhaps because of age, blood pressure, or, in particular, history of cerebrovascular disease) may be the clearest indication for antihypertensive treatment.
Publication
Journal: BMJ (Clinical research ed.)
March/8/1994
Abstract
OBJECTIVE
To determine the effects of "prolonged" antiplatelet therapy (that is, given for one month or more) on "vascular events" (non-fatal myocardial infarctions, non-fatal strokes, or vascular deaths) in various categories of patients.
METHODS
Overviews of 145 randomised trials of "prolonged" antiplatelet therapy versus control and 29 randomised comparisons between such antiplatelet regimens.
METHODS
Randomised trials that could have been available by March 1990.
METHODS
Trials of antiplatelet therapy versus control included about 70,000 "high risk" patients (that is, with some vascular disease or other condition implying an increased risk of occlusive vascular disease) and 30,000 "low risk" subjects from the general population. Direct comparisons of different antiplatelet regimens involved about 10,000 high risk patients.
RESULTS
In each of four main high risk categories of patients antiplatelet therapy was definitely protective. The percentages of patients suffering a vascular event among those allocated antiplatelet therapy versus appropriately adjusted control percentages (and mean scheduled treatment durations and net absolute benefits) were: (a) among about 20,000 patients with acute myocardial infarction, 10% antiplatelet therapy v 14% control (one month benefit about 40 vascular events avoided per 1000 patients treated (2P < 0.00001)); (b) among about 20,000 patients with a past history of myocardial infarction, 13% antiplatelet therapy v 17% control (two year benefit about 40/1000 (2P < 0.00001)); (c) among about 10,000 patients with a past history of stroke or transient ischaemic attack, 18% antiplatelet therapy v 22% control (three year benefit about 40/1000 (2P < 0.00001)); (d) among about 20,000 patients with some other relevant medical history (unstable angina, stable angina, vascular surgery, angioplasty, atrial fibrillation, valvular disease, peripheral vascular disease, etc), 9% v 14% in 4000 patients with unstable angina (six month benefit about 50/1000 (2P < 0.00001)) and 6% v 8% in 16,000 other high risk patients (one year benefit about 20/1000 (2P < 0.00001)). Reductions in vascular events were about one quarter in each of these four main categories and were separately statistically significant in middle age and old age, in men and women, in hypertensive and normotensive patients, and in diabetic and nondiabetic patients. Taking all high risk patients together showed reductions of about one third in non-fatal myocardial infarction, about one third in non-fatal stroke, and about one third in vascular death (each 2P < 0.00001). There was no evidence that non-vascular deaths were increased, so in each of the four main high risk categories overall mortality was significantly reduced. The most widely tested antiplatelet regimen was "medium dose" (75-325 mg/day) aspirin. Doses throughout this range seemed similarly effective (although in an acute emergency it might be prudent to use an initial dose of 160-325 mg rather than about 75 mg). There was no appreciable evidence that either a higher aspirin dose or any other antiplatelet regimen was more effective than medium dose aspirin in preventing vascular events. The optimal duration of treatment for patients with a past history of myocardial infarction, stroke, or transient ischaemic attack could not be determined directly because most trials lasted only one, two, or three years (average about two years). Nevertheless, there was significant (2P < 0.0001) further benefit between the end of year 1 and the end of year 3, suggesting that longer treatment might well be more effective. Among low risk recipients of "primary prevention" a significant reduction of one third in non-fatal myocardial infarction was, however, accompanied by a non-significant increase in stroke. Furthermore, the absolute reduction in vascular events was much smaller than for high risk patients despite a much longer treatment period (4.4% antiplatelet therapy v 4.8% control; five year
Publication
Journal: The Lancet Neurology
August/5/2010
Abstract
The term cerebral small vessel disease refers to a group of pathological processes with various aetiologies that affect the small arteries, arterioles, venules, and capillaries of the brain. Age-related and hypertension-related small vessel diseases and cerebral amyloid angiopathy are the most common forms. The consequences of small vessel disease on the brain parenchyma are mainly lesions located in the subcortical structures such as lacunar infarcts, white matter lesions, large haemorrhages, and microbleeds. Because lacunar infarcts and white matter lesions are easily detected by neuroimaging, whereas small vessels are not, the term small vessel disease is frequently used to describe the parenchyma lesions rather than the underlying small vessel alterations. This classification, however, restricts the definition of small vessel disease to ischaemic lesions and might be misleading. Small vessel disease has an important role in cerebrovascular disease and is a leading cause of cognitive decline and functional loss in the elderly. Small vessel disease should be a main target for preventive and treatment strategies, but all types of presentation and complications should be taken into account.
Publication
Journal: JAMA - Journal of the American Medical Association
May/28/2002
Abstract
BACKGROUND
Complications of atherosclerosis cause most morbidity and mortality in patients with diabetes mellitus. Despite the frequency and severity of disease, proven medical therapy remains incompletely understood and underused.
OBJECTIVE
To review the epidemiology, pathophysiology, and medical and invasive treatment of atherosclerosis in patients with diabetes mellitus.
METHODS
Using the index terms diabetes mellitus, myocardial infarction, peripheral vascular diseases, cerebrovascular accident, endothelium, vascular smooth muscle, platelets, thrombosis, cholesterol, hypertension, hyperglycemia, insulin, angioplasty, and coronary artery bypass, we searched the MEDLINE and EMBASE databases from 1976 to 2001. Additional data sources included bibliographies of identified articles and preliminary data presented at recent cardiology conferences.
METHODS
We selected original investigations and reviews of the epidemiology, pathophysiology, and therapy of atherosclerosis in diabetes. We selected randomized, double-blind, controlled studies, when available, to support therapeutic recommendations. Criteria for data inclusion (168 of 396) included publication in a peer-reviewed journal or presentation at a national cardiovascular society-sponsored meeting.
METHODS
Data quality was determined by publication in peer-reviewed literature. Data extraction was performed by one of the authors.
RESULTS
Diabetes mellitus markedly increases the risk of myocardial infarction, stroke, amputation, and death. The metabolic abnormalities caused by diabetes induce vascular dysfunction that predisposes this patient population to atherosclerosis. Blood pressure control, lipid-lowering therapy, angiotensin-converting enzyme inhibition, and antiplatelet drugs significantly reduce the risk of cardiovascular events. Although diabetic patients undergo revascularization procedures because of acute coronary syndromes or critical limb ischemia, the outcomes are less favorable than in nondiabetic cohorts.
CONCLUSIONS
Since most patients with diabetes die from complications of atherosclerosis, they should receive intensive preventive interventions proven to reduce their cardiovascular risk.
Publication
Journal: New England Journal of Medicine
July/25/2005
Abstract
BACKGROUND
Statins reduce the incidence of cardiovascular events in persons with type 2 diabetes mellitus. However, the benefit of statins in such patients receiving hemodialysis, who are at high risk for cardiovascular disease and death, has not been examined.
METHODS
We conducted a multicenter, randomized, double-blind, prospective study of 1255 subjects with type 2 diabetes mellitus receiving maintenance hemodialysis who were randomly assigned to receive 20 mg of atorvastatin per day or matching placebo. The primary end point was a composite of death from cardiac causes, nonfatal myocardial infarction, and stroke. Secondary end points included death from all causes and all cardiac and cerebrovascular events combined.
RESULTS
After four weeks of treatment, the median level of low-density lipoprotein cholesterol was reduced by 42 percent among patients receiving atorvastatin, and among those receiving placebo it was reduced by 1.3 percent. During a median follow-up period of four years, 469 patients (37 percent) reached the primary end point, of whom 226 were assigned to atorvastatin and 243 to placebo (relative risk, 0.92; 95 percent confidence interval, 0.77 to 1.10; P=0.37). Atorvastatin had no significant effect on the individual components of the primary end point, except that the relative risk of fatal stroke among those receiving the drug was 2.03 (95 percent confidence interval, 1.05 to 3.93; P=0.04). Atorvastatin reduced the rate of all cardiac events combined (relative risk, 0.82; 95 percent confidence interval, 0.68 to 0.99; P=0.03, nominally significant) but not all cerebrovascular events combined (relative risk, 1.12; 95 percent confidence interval, 0.81 to 1.55; P=0.49) or total mortality (relative risk, 0.93; 95 percent confidence interval, 0.79 to 1.08; P=0.33).
CONCLUSIONS
Atorvastatin had no statistically significant effect on the composite primary end point of cardiovascular death, nonfatal myocardial infarction, and stroke in patients with diabetes receiving hemodialysis.
Publication
Journal: Acta Neuropathologica
June/24/2012
Abstract
We present a practical guide for the implementation of recently revised National Institute on Aging-Alzheimer's Association guidelines for the neuropathologic assessment of Alzheimer's disease (AD). Major revisions from previous consensus criteria are: (1) recognition that AD neuropathologic changes may occur in the apparent absence of cognitive impairment, (2) an "ABC" score for AD neuropathologic change that incorporates histopathologic assessments of amyloid β deposits (A), staging of neurofibrillary tangles (B), and scoring of neuritic plaques (C), and (3) more detailed approaches for assessing commonly co-morbid conditions such as Lewy body disease, vascular brain injury, hippocampal sclerosis, and TAR DNA binding protein (TDP)-43 immunoreactive inclusions. Recommendations also are made for the minimum sampling of brain, preferred staining methods with acceptable alternatives, reporting of results, and clinico-pathologic correlations.
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