Progressive cerebral ischemia antedates cerebrovascular symptoms by two years

Clinicoradiological evaluation of oxidative stress activity in acute cerebral infarction in the first 24 h and the qualitative importance of dysfunctional HDL in stroke

BACKGROUND

Acute cerebral infarction (ACI) occurs as a result of instant disruption of vascular flow that causes disbalance between oxidative/antioxidative activity. We examined the relationship of serum neuro-oxidative stress parameters with stroke severity and infarct volume in ACI and emphasized the qualitative importance of high-density lipoprotein (HDL) on its relationship with myeloperoxidase (MPO) and paraoxonase-1 (PON1) in the acute period of stroke.

METHODS

One hundred ACI patients applied within the first 24 h and 50 healthy volunteers were included. The patient group was evaluated with demographic data (including arrival serum biochemical assessment), clinical disability scores, infarct volume, serum oxidative/antioxidative parameters (lipid hydroperoxide (LOOH), MPO, PON1, MPO/PON ratio). The relevant serum parameters were compared with the control group. Dysfunctional HDL measurement was based on detecting dysfunctionality as a result of a high positive correlation between the dysfunctional feature of HDL and the MPO/PON ratio. The correlation of serum parameters, clinical disability score, and infarct volume were evaluated, and independent analyses of variability with comorbidities were performed.

RESULTS

A negative correlation between PON1 and arrival NIH score/scale (NIHSS), LOOH and discharge modified rankin scale (mRS), triglyceride level, and infarct volume; a positive correlation between MPO\PON ratio and infarct volume was determined. Logistic regression analyses showed that hypertension, diabetes, and high HbA1C may be predictors of stroke severity, and diabetes mellitus, high HbA1C, infarct volume, and high NIHSS score may be predictors of early disability (p < 0.005). The ROC curve analysis revealed that determining the cut-off value for LOOH is of importance in determining early disability scores (7.2 and 6.2, respectively).

DISCUSSION

The balance between oxidative and antioxidative stress parameters and their quantitative/qualitative changes is of importance, especially in the acute period of ACI. Dysfunctional HDL's evolution and its relationship with other oxidants are significant not only in the cardiovascular aspect but also in the clinicoradiological aspect.

Cerebro-renal interaction and stroke

Stroke is an event causing a disturbance in cerebral function leading to death and disability worldwide. Both acute kidney injury and chronic kidney disease (CKD) are associated with an increased risk of stroke and cerebrovascular events. The underlying mechanistic approach between impaired renal function and stroke is limitedly explored and has attracted researchers to learn more for developing therapeutic intervention. Common risk factors such as hypertension, hyperphosphatemia, atrial fibrillation, arteriosclerosis, hyperhomocysteinemia, blood-brain barrier disruption, inflammation, etc. are observed in the general population, but are high in renal failure patients. Also, risk factors like bone mineral metabolism, uremic toxins, and anemia, along with the process of dialysis in CKD patients, eventually increases the risk of stroke. Therefore, early detection of risks associated with stroke in CKD is imperative, which may decrease the mortality associated with it. This review highlights mechanisms by which kidney dysfunction can lead to cerebrovascular events and increase the risk of stroke in renal impairment.

Reducing Hypertriglyceridemia in Elderly Patients with Cerebrovascular Disease Stabilizes or Improves Cognition and Cerebral Perfusion

Effects of lowering serum triglyceride levels were investigated among 44 el derly hypertriglyceridemic patients with risk factors for stroke, reduced cere bral perfusion, and a history compatible with symptomatic occlusive cerebro vascular disease. Patients were randomly assigned to either treatment with gem fibrozil, a lipid-lowering agent, or control conditions. Subjects in both groups were instructed to follow a diet recommended for lowering serum lipid levels, while the treatment group was additionally administered 600 mg daily of gemfi brozil. Subjects assigned to the treatment group (n = 22) showed significant re ductions in serum triglyceride levels (p < .0005). Control subjects (n=22) did not show any significant changes in serum triglyceride levels. There were also no significant changes in total cholesterol levels in either group. Analyses of values for mean bihemispheric gray matter cerebral blood flow measured by the xenon 133 inhalation method and cognitive scores tested by the Cognitive Ca pacity Screening Examination indicated that gemfibrozil-treated patients main tained significantly higher levels of cerebral perfusion and cognitive perform ance than untreated controls did. Regression analyses for different treatment intervals indicated that both cerebral blood flow and cognition showed linear improvements that correlated directly with the duration of treatment. Lowering triglyceride levels in hyperlipidemic subjects appears to benefit cerebral perfu sion and cognitive performance after four to six months.

The Impact of Aging on Cardio and Cerebrovascular Diseases

A growing number of evidences report that aging represents the major risk factor for the development of cardio and cerebrovascular diseases. Understanding Aging from a genetic, biochemical and physiological point of view could be helpful to design a better medical approach and to elaborate the best therapeutic strategy to adopt, without neglecting all the risk factors associated with advanced age. Of course, the better way should always be understanding risk-to-benefit ratio, maintenance of independence and reduction of symptoms. Although improvements in treatment of cardiovascular diseases in the elderly population have increased the survival rate, several studies are needed to understand the best management option to improve therapeutic outcomes. The aim of this review is to give a 360° panorama on what goes on in the fragile ecosystem of elderly, why it happens and what we can do, right now, with the tools at our disposal to slow down aging, until new discoveries on aging, cardio and cerebrovascular diseases are at hand.

Interactive relations of blood pressure and age to subclinical cerebrovascular disease

OBJECTIVE

To examine interactive relations of blood pressure (BP) and age to MRI indices of subclinical cerebrovascular disease in middle-aged to older adults.

METHODS

One hundred and thirteen stroke-free and dementia-free, community-dwelling adults (ages 54-81 years; 65% men; 91% white) engaged in (1) clinical assessment of resting SBP and DBP; (2) MRI rated for periventricular white matter hyperintensities (WMH) and deep WMH silent brain infarction (SBI) and brain atrophy (i.e. ventricular enlargement and sulcal widening ). Principal components analysis of the MRI ratings yielded a two-component solution--(1) periventricular and deep WMH SBI; and (2) ventricular enlargement, sulcal widening.

RESULTS

Relations of SBP, DBP and pulse pressure (PP) (and their interactions with age) to each MRI component were examined in multiple regression analyses adjusted for age, sex, fasting plasma glucose and cholesterol, and antihypertensives. For component 1, results indicated significant interactions of SBP and PP with age (P < 0.05); higher levels of SBP and PP were associated with greater white matter disease and brain infarction at younger ages (≤ 68 years). Significant interactions of SBP and DBP with age were also noted for component 2 (P < 0.05); higher levels of BP were associated with greater brain atrophy at younger ages (≤ 63 years).

CONCLUSION

: Higher BP and PP are associated with greater subclinical cerebrovascular disease most prominently in the 'young old'. Appropriate management of hypertension and arterial stiffening may be critical to the preservation of brain structure with ageing.

Reduced cerebral blood flow in older men with higher levels of blood pressure

OBJECTIVE

To examine relations of blood pressure (BP) with single photon emission computed tomography (SPECT)-derived estimates of cerebral blood flow in older men and women.

METHODS

Seventy-four stroke and dementia-free, community-dwelling older adults (ages 54-83 years; 68% men; 91% white) free of major medical, neurological, or psychiatric disease, engaged in clinical assessment of resting SBP and DBP, MRI rated for brain atrophy, and brain single photon emission computed tomography (SPECT) studies with computerized coding of cortical and select subcortical regions of interest.

RESULTS

Given significant interactions of BP and sex with respect to multiple SPECT outcomes, sex-stratified multiple regression models were computed. Models were adjusted for age, fasting glucose levels, antihypertensive medication, BMI, and MRI ratings of brain atrophy. In men (n = 50), higher levels of SBP and/or DBP were associated significantly with lower estimates of cerebral perfusion in the right and left frontal, temporal, parietal, and occipital cortex, thalamus, head of caudate, and cingulate cortex accounting for up to 28% of the variance in these measures (P < 0.05). In women (n = 24), higher DBP was related marginally to higher levels of perfusion in the right temporal cortex (P = 0.05).

CONCLUSION

Higher resting SBP or DBP was associated with lower levels of cerebral perfusion in otherwise healthy older men, but not women, in the present sample. Reduced cerebral blood flow may play a pathogenic role in increasing risk for stroke, dementia, and/or cognitive decline, particularly among older men with high BP.

Effects of cilostazol on cerebral blood flow, P300, and serum lipid levels in the chronic stage of cerebral infarction

The effects of cilostazol (Pletaal, Otsuka Pharmaceutical Co., Tokyo, Japan) on cerebral blood flow, P300 event-related potentials, and serum lipid levels were examined in patients in the chronic stage of cerebral infarction. This study included 20 patients (13 men and 7 women, mean age 67 +/- 11 years) with cerebral infarction who had taken ticlopidine (100 mg orally, twice a day). Quantitative cerebral blood flow measurements by Patlak plot analysis, ultrasound examinations of the common carotid arteries, and measurements of P300 event-related potentials and serum lipid levels were performed. Ticlopidine was then replaced with cilostazol (100 mg orally, twice a day) while other medications remained unchanged. The same examinations were performed again 3 months later. After replacement of ticlopidine with cilostazol, cerebral blood flow significantly increased in the frontal white matter, temporal cortex, and occipital cortex compared with cerebral blood flow before replacement with cilostazol. Ultrasonograms of the common carotid arteries showed no significant differences in intima-media thickness before and after replacement. However, peak systolic velocity, time-averaged peak velocity, and volume flow all significantly increased after replacement. Blood flow in the frontal white matter showed a significant negative correlation with P300 latency before and after replacement of ticlopidine with cilostazol. And P300 latency improved significantly after replacement with cilostazol. Regarding lipid levels, total cholesterol, triglycerides, and remnant-like particles-cholesterol all decreased significantly after replacement with cilostazol. Cilostazol, an inhibitor of platelet aggregation, was thus concluded to be effective in improving cerebral blood flow, cerebral function, and serum lipid levels in patients in the chronic stage of cerebral infarction.

Longitudinal Changes in Cerebral Blood Flow in the Older Hypertensive Brain

BACKGROUND AND PURPOSE

Changes in patterns of regional cerebral blood flow (rCBF) were assessed over a period of 6 years in 14 treated hypertensive participants (HTNs) and 14 age-matched healthy older participants (healthy controls [HCs]) in the Baltimore Longitudinal Study of Aging.

METHODS

Resting-state PET scans collected at years 1, 3, 5, and 7 were used to determine differences in longitudinal patterns of rCBF change in HTNs relative to HCs. Pulse pressure, arterial pressure, systolic/diastolic blood pressure, and hypertension duration were also correlated with patterns of rCBF change in the HTN group.

RESULTS

Relative to HCs, the HTN group shows greater rCBF decreases in prefrontal, anterior cingulate, and occipital areas over time, suggesting that these regions are more susceptible to hypertension-related dysfunction with advancing age. The HTN group also fails to show preservation of function over time in motor regions and in the temporal cortex and hippocampus as observed in HC. Although pulse pressure, mean arterial pressure, and systolic and diastolic pressure all correlate similarly with longitudinal rCBF changes, increased duration of hypertension is associated with decreased rCBF in prefrontal and anterior cingulate areas of functional vulnerability observed in the HTN group.

CONCLUSIONS

These results show that hypertension significantly affects resting brain function in older individuals and suggest that duration of hypertension contributes significantly to the patterns of change over time.

Evaluation of cerebral blood flow by single-photon emission computed tomography in young Asian Indians with hypertension

The objective of the study was to investigate abnormalities of regional cerebral blood flow (rCBF) in young (age 33.0+/-6.3 years; range 21-45 years) non-diabetic and normolipidemic Asian Indians with hypertension. The rCBF was assessed with single-photon emission computed tomography (SPECT) in patients with hypertension (n = 33) and healthy controls (n = 20). The SPECT findings were normal in 41 subjects and showed abnormalities of cerebral perfusion in 10 subjects, all of which were hypertensive patients. These observations are extremely important for a vast number of young hypertensive patients in India. To prevent cerebrovascular accidents in future, patients with hypertension and decreased rCBF should be carefully monitored and their hypertension should be strictly controlled. These subjects may also be researched as potential candidates for preventive antiplatelet therapy.

Proton magnetic resonance spectroscopy and single photon emission computed tomography study of the brain in asymptomatic young hyperlipidaemic Asian Indians in North India show early abnormalities

OBJECTIVE

To evaluate brain metabolism and cerebral blood flow in young patients with hyperlipidaemia.

PATIENTS AND METHODS

Proton magnetic resonance spectroscopy ((1)H MRS) and single photon emission computed tomography (SPECT) of the brain was carried out in 19 asymptomatic young patients with hyperlipidaemia (mean age 32.6 +/- 6.0 years, range 22-45 years) and 21 age-matched healthy controls divided into the following three groups; (i) hyperlipidaemics on pharmacological treatment (group 1, n = 13), (ii) hyperlipidaemics not on pharmacological treatment (group 2, n = 6) and (iii) control group of healthy subjects (group 3, n = 21).

RESULTS

No statistical difference was observed in the brain metabolite ratios between controls and hyperlipidaemic patients (both treatment naive and treated) in the (1)H NMR study. Two hyperlipidaemic patients showed a lactate peak and one had a lipid peak. The SPECT study was abnormal in seven hyperlipidaemic patients. In the pooled data, 50% subjects with high serum triglyceride (TG) levels as opposed to 14% subjects with normal serum TG levels showed cerebral hypoperfusion. The choline/creatine (Cho/Cr) ratio of the occipital region of the brain showed correlation with the excess percentage of body fat (%BF) and low levels of high density lipoprotein cholesterol (HDL-C) compared to those with normal %BF and normal HDL-C levels, respectively, in pooled data of all subjects. The N-acetyl aspartate (NAA)/Cho ratio also showed correlation with hypercholesterolaemia. Serum TG levels were positively correlated with the NAA/Cr ratio (r = 0.62, P < 0.05) and the Cho/Cr ratio (r = 0.63, P < 0.05) in the parieto-temporal area in group 1 patients.

CONCLUSION

The study revealed no difference in the brain metabolite ratios between controls and hyperlipidaemic patients, while some hyperlipidaemic patients showed abnormalities of cerebral blood flow. Brain metabolite ratios were also influenced by certain parameters of body composition and lipids. As abnormal body composition, hypertriglyceridaemia and low levels of HDL-C are prevalent in Asian Indians, such data are important and indicate a need for further study.

Cerebral blood flow and metabolism in silent brain infarction and related cerebrovascular disorders

The appropriate management of silent stroke requires better understanding of the haemodynamic status in the brain. However, only a few studies have examined cerebral blood flow and metabolism in subjects with silent stroke. Positron emission tomography demonstrated a slight decrease in cortical blood flow with an increase in oxygen extraction fraction (ie misery perfusion) in subjects with silent brain infarction, whereas both cerebral blood flow and oxygen metabolism decreased in patients with symptomatic brain infarction (matched hypoperfusion). These findings confirm that brain circulation is haemodynamically compromised in subjects with silent stroke. Another important point is that subcortical silent stroke may induce a reduction in cortical blood flow and metabolism by a disconnection mechanism (ie diaschisis) between the cortex and the subcortical structures. Silent infarction is not innocuous in terms of compromised cerebral circulation, which may lead to cognitive decline or subsequent clinical stroke. In the future, further developments in functional imaging will permit a more sophisticated analysis of brain circulation and metabolism in silent stroke.

Aging and cerebrovascular disease

Aging influences cerebrovascular disease expression by a variety of mechanisms. Age-related changes in cerebral autoregulation, cellular metabolism, the blood-brain barrier, and autonomic function may leave the cerebrovascular system vulnerable to injury. Certain cerebrovascular disease, such as atrial fibrillation, watershed infarctions, carotid artery atherosclerosis, cerebral hemorrhages, subdural hematomas, and transient global amnesia manifest in the elderly. Vascular dementia and white matter disease are better understood with newer neuroimaging studies, careful neuropsychological and histopathologic examinations. Atherosclerosis and cerebral amyloid angiopathy may have larger roles than previously understood in Alzheimer's disease.

Blood flow velocity changes in the middle cerebral artery as an index of the chronicity of hypertension

This study was designed to demonstrate cerebral hemodynamic changes related to hypertension using transcranial Doppler ultrasonography. We measured the flow velocities and the Gosling pulsatility index of the middle cerebral artery and the internal carotid artery in 94 stroke-free, hypertensive patients and 81 age- and gender-matched healthy controls. Compared with the control subjects, patients with a longer duration (> or = 5 years) of hypertension showed significantly lower flow velocities of the middle cerebral artery and a higher Gosling pulsatility index of the middle cerebral- and the internal carotid artery. These differences were not observed in patients with a shorter duration of hypertension (<5 years). In the patient group, the mean velocity of the middle cerebral artery was significantly and inversely correlated with the duration of hypertension. Decreased flow velocity with increased pulsatility observed in this study suggest that alterations in the small cerebral vessels and arterioles contribute primarily to cerebral hemodynamic changes occurring in long-standing hypertension and also suggest the possible usefulness of transcranial Doppler in monitoring the progression of cerebral atherogenesis related to hypertension.

Stroke and alcohol intake in a hospital population. A case-control study

BACKGROUND AND PURPOSE

The aim of the study was to assess whether excessive alcohol intake is an independent risk factor for stroke.

METHODS

A case-control study was undertaken in 200 consecutive ischemic and hemorrhagic stroke patients and 372 age- and sex-matched control subjects (170 hospital-based and 202 community-based individuals). Data were collected through direct interview regarding demographics, risk factors for stroke, current daily alcohol consumption, and diagnosis of alcoholism. Blood was also taken to test the common biological markers of alcohol intake (erythrocyte mean cell volume, uric acid, aspartate aminotransferase, and gamma-glutamyl transferase).

RESULTS

After controlling for the most significant risk factors (antecedent strokes, hypertension, diabetes, smoking) and using hospital control subjects for reference, we determined the risk of stroke to be 2.2 (95% confidence interval [CI], 1.2 to 4.0) in moderate drinkers (men, < or = 60 g/d; women, < or = 40 g/d) and 2.9 (95% CI, 1.4 to 6.1) in heavy drinkers (men, > 60 g/d; women, > 40 g/d). The corresponding risk values obtained when we compared case subjects and external control subjects were 1.4 (95% CI, 0.8 to 2.7) and 3.0 (95% CI, 1.3 to 7.0). Even with some fluctuations across groups, the risk did not change significantly after subgroup analysis in men, patients with first-ever stroke, patients with ischemic stroke, and after exclusion of subjects with risk factors for stroke. Compared with hospital and external control subjects, stroke patients included a higher proportion of heavy drinkers (26.6% versus 20.6% versus 10.8%), alcoholics (14.6% versus 7.7% versus 2.5%), and cases with abnormal erythrocyte mean cell volume (63.0% versus 47.6% versus 34.2%) or gamma-glutamyl transferase (35.5% versus 32.4% versus 12.9%). Mean alcohol consumption was 42.2 g/d in the case subjects, 30.8 g/d in the hospital control subjects, and 23.2 g/d in the external control subjects.

CONCLUSIONS

The study indicates that alcohol can be considered an independent risk factor for stroke in Italy.

The impact of alcohol and hypertension on stroke incidence in a general Japanese population. The Hisayama Study

BACKGROUND AND PURPOSE

The relationship between alcohol intake and stroke has been inconsistent in previous studies. We examined the separate and combined effects of drinking habits and hypertension on stroke incidence in a prospective survey of a general Japanese population.

METHODS

A total of 1621 stroke-free Hisayama residents aged 40 years or older were classified by their alcohol intake into nondrinkers, light drinkers (< 34 g of ethanol per day), and heavy drinkers (> or = 34 g of ethanol per day) and followed up prospectively for 26 years from 1961.

RESULTS

During the follow-up period, cerebral infarction developed in 244 subjects and cerebral hemorrhage in 60. For men, the incidence of cerebral hemorrhage increased significantly with rising alcohol consumption. In contrast, the incidence of cerebral infarction was slightly lower in light drinkers than in nondrinkers, while it increased significantly in heavy drinkers compared with light drinkers. Female drinkers had a lower incidence of cerebral infarction but a slightly higher incidence of cerebral hemorrhage than nondrinkers, as did male light drinkers. Among the hypertensive subjects, the age- and sex-adjusted relative risk of cerebral hemorrhage was significantly elevated in heavy drinkers versus abstainers (3.13; 95% confidence interval [CI], 1.08 to 9.10), but the increase was not significant for light drinkers. In contrast, the relative risk did not significantly increase for normotensive light and heavy drinkers. Compared with hypertensive light drinkers, the relative risk of cerebral infarction significantly increased in hypertensive heavy drinkers (1.96; 95% CI, 1.08 to 3.57) but remained unchanged in normotensive heavy drinkers. Significant associations between alcohol intake and stroke were substantially the same even after controlling for other risk factors in multivariate analysis.

CONCLUSIONS

Among hypertensive individuals, heavy alcohol consumption leads to a significant increase in the risk of cerebral hemorrhage, suggesting a synergistic effect of alcohol and hypertension, while light alcohol consumption significantly reduces the risk of cerebral infarction.

Reduction of functional neuronal connectivity in long-term treated hypertension

BACKGROUND AND PURPOSE

Anatomic imaging of patients with chronic well-treated hypertension has demonstrated dilatation of the lateral cerebral ventricles and left brain atrophy, whereas positron emission tomography has shown only subtle reductions in regional cerebral metabolic rates for glucose in some subcortical nuclei. To further explore the implications of the imaging changes, an analytic technique designed to determine functional neuronal connectivity between regions of interest (ROIs) was applied to the data on regional cerebral metabolic rates for glucose to determine if and where in the brain reduction of functional neuronal connectivity occurred.

METHODS

Glucose metabolism was measured by positron emission tomography in 17 older men (age, 68 +/- 8 years) with well-controlled, noncomplicated hypertension of at least 10 years' duration and in 25 age- and sex-matched healthy control subjects. A significant correlation difference analysis was performed to determine which ROI pairs had reduced correlation coefficients (reduced functional neuronal connectivity). The vascular pattern of the reduction was determined after allocating the ROIs to their appropriate vascular territories.

RESULTS

Compared with the control subjects, hypertensive patients had reduced correlation coefficients in cortical territories of the internal carotid arteries but not of the vertebrobasilar arteries. The border zone supplied by the middle and anterior cerebral arteries was most affected.

CONCLUSIONS

The border zone between the anterior and middle cerebral arteries is vulnerable to ischemia from carotid pathology, systemic hypotension, or both. We hypothesize that although these hypertensive patients were "well controlled" and had normal neuropsychological tests, they may have experienced ischemia severe enough to cause border zone reduction of functional neuronal connectivity as a result of carotid pathology, antihypertensive medications, hypotensive episodes with a right-shifted autoregulation curve, or other factors in isolation or combination.

Long-term changes in cerebral blood flow according to different types of ischemic stroke

Recurrence of ischemic stroke may be related to chronic hemodynamic failure of the brain. Long-term changes in cerebral blood flow (CBF) remain undetermined for each ischemic stroke subtype. We performed the present study to clarify this issue. The study group consisted of 77 unilateral, hemispheric, ischemic stroke patients who had a single stroke episode; atherothrombotic stroke in 34, cardioembolic in 26 and lacunar in 17. We measured baseline CBF in the affected and unaffected hemispheres 1.0-3.4 months after stroke onset, then repeated the measurements 10 months to 10 years later (mean 43.7 months), with the xenon-133 inhalation method. We analyzed changes in CBF in relation to other clinical characteristics. CBF in the affected hemisphere changed differently among the stroke subtypes (P < 0.01); increased in the atherothrombotic group, particularly within 40 months of stroke; remained unchanged in the cardioembolic group; and decreased in the lacunar group, especially later than 40 months of stroke. In the atherothrombotic group, CBF increased in hypertensive patients but decreased in normotensives (7.9 +/- 2.4% and -3.6 +/- 3.9%, respectively; P < 0.05). Present results suggest that long-term changes in CBF depend on ischemic stroke subtype. Development of collateral circulation may occur after several years in atherothrombotic stroke patients. The findings raise doubts about the significance of chronic hemodynamic failure as a cause of stroke recurrence.

Improvement in symptoms of depression and in an index of life stressors accompany treatment of severe hypertriglyceridemia

In 14 men and nine women referred because of severe primary hypertriglyceridemia, our specific aim in a 54-week single-blind treatment (Rx) period was to determine whether triglyceride (TG) lowering with a Type V diet and Lopid would lead to improvement in symptoms of depression, improvement in an index of life stressors, change in locus of control index, and improved cognition, as serially tested by Beck (BDI), Hassles (HAS) and HAS intensity indices, Locus of Control index, and the Folstein Mini-Mental status exam. On Rx, median TG fell 47%, total cholesterol (TC) fell 15%, and HDLC rose 19% (all p < or = 0.001). BDI fell at all nine Rx visits (p < or = 0.001), a major reduction in a test of depressive symptoms. The HAS score also fell at all nine visits (p < or = 0.05 - < or = 0.001). Comparing pre-Rx baseline BDI vs BDI at 30 and 54 weeks on Rx, there was a major shift towards absence or amelioration of depressive symptoms (chi 2= 5.9, p = 0.016). On Rx, the greater the percent reduction in TG, the greater the percent fall in BDI (r = 0.47, p < or = 0.05); the greater the percent reduction in TC, the greater the percent fall in HAS (r = 0.41, p < or = 0.05). Improvement in the BDI and HAS accompanied treatment of severe hypertriglyceridemia, possibly by virtue of improved cerebral perfusion and oxygenation. There may be a reversible causal relationship between high TG and symptoms of depression.

Cerebrovascular disorders and alcohol intake: preliminary results of a case-control study

The role of alcohol as a risk factor for cerebral infarction and hemorrhage has been assesed in 200 middle-aged and elderly stroke patients and 200 controls matched for age, sex and hospital admission date. Computed tomographic brain scans were done in all but 10 of the stroke patients. Alcohol intake was reckoned on the 12 months preceding hospitalization and expressed in grams daily according to a standard nomogram. The Michigan Alcoholism Screening Test was used for the diagnosis of alcoholism. Cerebral infarction was present in 59% of the stroke patients and cerebral hemorrhage in 9%. The role of alcohol as risk factor for stroke proved to be small (Odds Ratio 1.86) and was practically lost after adjustment for the most common risk factors for cerebrovascular disorders (previous strokes, arterial hypertension, diabetes, obesity and hyperlipidemia). Our findings seem to suggest that alcohol is not an independent risk factor for stroke in the middle-aged and elderly. The data are, however, preliminary and are discussed in the light of methological problems.

Pure topographical disorientation due to a deep-seated lesion with cortical remote effects

Lesions producing pure topographical disorientation syndromes are classically located either in the right parietal region either in the right parahippocampal gyrus. The patient described in the present study was admitted to hospital after sudden onset of a left hemiparesis. The lesion at CT scan was located in the posterior limb of the right internal capsule. Neuropsychological assessment was normal except for the presence of a major topographical disorientation and of mnestic disturbances for visuo-spatial material leading us to attribute topographical disorientation to a specific loss of topographical memory. Regional cerebral blood flow measurements disclosed a right parietal hypoperfusion. This remote cortical effect could account for the presence of the neuropsychological disorders.

Incidence of silent lacunar lesion in normal adults and its relation to cerebral blood flow and risk factors

BACKGROUND AND PURPOSE

There are few reports comparing incidence of silent lacunar lesions detected by magnetic resonance imaging and cerebral blood flow in neurologically normal adults.

METHODS

We studied the incidence of such lesions and its relation to cerebral blood flow and risk factors in 246 neurologically normal adults (145 men, mean age 62 years; 101 women, mean age 60 years) who received health screening examinations of the brain.

RESULTS

Thirty-two subjects (13%) had possible silent lacunar lesions (66% of these were recognized by both T1- and T2-weighted image). The regional cerebral blood flow measured by the xenon-133 inhalation method was significantly lower in subjects with silent lacunes than in those without (p less than 0.02). Cerebral blood flow was mildly but significantly decreased in those with silent lacunes (p less than 0.05). Periventricular hyperintensity was closely related to silent lacune (p less than 0.01). However, there was no significant difference in cerebral blood flow between subjects with and without apparent periventricular hyperintensity.

CONCLUSIONS

Silent lacunar lesion was closely related to decrease of cerebral circulation and may be an important risk factor for symptomatic cerebrovascular disease.

Remote cortical dysfunction in aphasic stroke patients

We studied the effect of deep-seated left hemispheric lesions on cortical blood flow in 18 right-handed aphasic stroke patients. Regional cerebral blood flow was measured at rest and during the performance of a functional naming test using the two-dimensional xenon-133 inhalation method. Compared with 10 controls, at rest the patients showed regional cortical hypoperfusion in the left frontoparietal region. In the controls, activation patterns from the rest to the test condition involved mainly the left hemisphere areas. In the patients, a lack of blood flow change was observed in several areas that were usually hypoperfused at rest. However, in patients with slight verbal expression disorders there were obvious blood flow increases in other brain regions in both hemispheres. Such cortical functional reorganization and the presence of a remote cortical dysfunction could play a role in the pathophysiology of language disorders.

Brain activation during a linguistic task in conduction aphasia

In order to investigate functional cortical reorganization during recovery from conduction aphasia, regional cerebral blood flows (rCBF) were measured by the two-dimensional 133 Xenon inhalation method in ten stroke patients. rCBF measurements were performed at rest and during the performance of a linguistic task, one month and three months after onset. The analysis of flow changes from rest to test condition indicates an increasing contribution of the right hemisphere as time goes on. The absence of flow increase in Broca's region suggests that this region is definitively disconnected from posterior language "centers" by the arcuate fasciculus lesion.

Randomized clinical trial of daily aspirin therapy in multi-infarct dementia. A pilot study

Seventy multi-infarct dementia patients were randomized into an aspirin-treated group and an untreated control group for an exploratory investigation to determine any effects of 325 mg aspirin daily on cognitive performance. The control group did not receive placebo but evaluations were carried out in a blinded manner. The index group (N = 37, mean age 67.1 years) received 325 mg of aspirin by mouth once daily while the control group (N = 33, mean age 67.6 years) was followed and treated in a similar manner except that they received no aspirin. Both groups had comparable risk factors for stroke, which were treated similarly, as well as comparable initial cerebral blood flow values, as measured by the 133xenon inhalation method, and initial scores on Cognitive Capacity Screening Examination testing. Patients were evaluated at intervals of one year. Significant improvements were demonstrated for cerebral perfusion values (P less than .0001) and cognitive performance scores (P less than .0001) among aspirin-treated patients compared to untreated controls at each of three annual follow-up evaluations. Both men and women benefited from aspirin therapy and their quality of life and independence appeared to be improved, which was not apparent in the control group. Daily aspirin appears to improve or stabilize declines in cerebral perfusion and cognition among patients with multi-infarct dementia.

Dementia due to vascular disease--a multifactorial disorder

This review was undertaken to evaluate critically the literature pertaining to vascular dementia with the objective of determining a more useful and scientifically supported definition of vascular dementia, its relation to other causes of dementia, and the biologic mechanisms involved in its causation.

White matter signal abnormalities in normal individuals: correlation with carotid ultrasonography, cerebral blood flow measurements, and cerebrovascular risk factors

We studied 52 asymptomatic subjects using magnetic resonance imaging, and we compared age-matched groups (51-70 years old) with and without white matter lesions with respect to carotid ultrasonography, cerebral blood flow (xenon-133 injection), and cerebrovascular risk factors. In the group with white matter signal abnormalities, we noted a higher frequency of extracranial carotid artery disease, a lower mean gray matter blood flow (F1), and a significant reduction (p less than 0.05) in blood flow of the slow-flowing (F2) compartment. Hypertension, diabetes mellitus, and cardiac diseases (p less than 0.002) were found more often in this group. Our results indicate that a higher incidence of changes known to be associated with an increased risk for stroke exists in the presence of white matter lesions in normal elderly individuals.

Haemodynamics and oxygen metabolism in patients after reversible ischaemic attack or minor ischaemic stroke assessed with positron emission tomography

Regional cerebral blood flow (CBF), blood volume (CBV) and oxygen metabolic rate (CMRO2) were evaluated and compared among normals, patients with recent reversible ischaemic attacks (RIAs) and patients with chronic minor infarction using positron emission tomography. Average CBF together with CMRO2 significantly decreased in the infarction group in the middle cerebral artery territory of the affected hemisphere while the mean values for RIAs were intermediate between the other two groups. CBV also reduced, however it was more preserved compared to flow as seen in decreased CBF/CBV values. Significant interhemispheric difference was found in CBF/CBV ratio, but it did not clearly correlate with OEF changes. Higher OEF was noted only in the restricted brain regions of RIAs where CBF showed large hemispheric asymmetry. However, in other regions, the coupled decline of blood flow and metabolism was found which suggests tissue damage or neuronal cell loss in the brain with previous RIA symptoms.

Additional predisposing risk factors for atherothrombotic cerebrovascular disease among treated hypertensive volunteers

A 7-year prospective study of a cohort of 107 neurologically normal elderly hypertensive volunteers (mean age, 65.8 +/- 8.3 years) was undertaken to investigate the predictive validities of additional risk factors for atherothrombotic cerebrovascular disease including stroke, transient ischemic attacks, reversible ischemic neurological deficits, and multi-infarct dementia. This longitudinal study has been in progress now for 7 years with a mean follow-up interval of 50.12 +/- 5.76 months. Among 107 formerly symptom-free, normal hypertensive volunteers, 25 (23%) have developed cerebrovascular disease, 7 (6.5%) sustained a stroke, 10 (9.3%) developed multi-infarct dementia, and 18 (16.8%) have transient ischemic attacks. None have suffered intracranial hemorrhage. Mean gray matter cerebral blood flow (CBF) values measured at the initial visit were sensitive predictors of cerebrovascular disease. Eight of 16 hypertensives (50%) with initial CBF values below 60.0 ml/100 g/min now exhibit signs and symptoms of cerebrovascular disease, while 11 of 43 hypertensives (25.6%) with initial CBF values between 60.1 and 69.9 ml/100 g/min and only 6 of 48 (12.5%) with initial CBF levels above 70.0 developed cerebrovascular disease. Incidence of cerebrovascular disease among cigarette smoking hypertensive volunteers (32.5%) was significantly greater than among nonsmokers (17.2%).

Alcohol and stroke

Alcohol might contribute to stroke in several ways: induction of cardiac arrhythmias and cardiac wall motion abnormalities which predispose to cerebral embolism, induction of hypertension, enhancement of platelet aggregation and activation of the clotting cascade, and reduction of cerebral blood flow by stimulation of cerebral vascular smooth muscle contraction or by altering cerebral metabolism. While these pathophysiological mechanisms have gained enthusiastic experimental and theoretical support, the findings are preliminary and will require further large-scale clinical and epidemiological analyses to substantiate their roles as causal factors or potentiators of stroke. Documentation of measurable platelet and coagulation cascade abnormalities reported in healthy volunteers who have ingested alcohol will need to be confirmed on a broader scale in stroke patients with recent ethanol consumption. The risk of stroke in those with alcohol-induced atrial fibrillation and cardiomyopathy must be ascertained for the general population. While the experimental evidence is exciting and provocative, epidemiological evidence also suggests a link between alcohol consumption and stroke. Regular alcohol ingestion is associated with hypertension, fatal and nonfatal intracranial hemorrhage, cerebral infarction, and increased risk of death from stroke. Recent, less stringently controlled studies suggest that alcohol consumption is a risk factor for cerebral infarction in young adults with occasional ethanol intoxication and middle-aged women and young men with occasional alcohol intoxication and regular heavy drinking. Alcohol may also be a risk factor for subarachnoid hemorrhage.

Prospective analysis of long term control of mild hypertension on cerebral blood flow

A group of 12 otherwise normal elderly volunteers (mean age = 69.8 years), were detected to have mild hypertension. Cerebral blood flow (CBF) values were measured using 133Xe inhalation method prior to initiating medical treatment and repeated at 6, 12, 24 and 36 months after BP was adequately controlled and restored to normal (below 150/90). Results indicate that CBF values increased markedly during follow-up intervals at 6, 12 and 24 months but not at 36 months. Hypertension is known to be a risk factor for stroke and 4 of the 12 subjects subsequently developed symptoms of cerebrovascular disease (stroke, multi-infarct dementia or transient ischemic attacks) despite control of hypertension. Analyses separating asymptomatic and symptomatic groups indicated that the eight asymptomatic patients continued to maintain increased CBF levels throughout the entire three year interval, whereas the 4 symptomatic patients developed declines in CBF which began, and progressively decreased below the initial pretreatment values, during the second and third years.

Epileptic seizures due to thrombotic and embolic cerebrovascular disease in older patients

Thromboembolic vascular disease is a frequent precipitant of seizures, and is the most common etiology in older patients. The occurrence of seizures shortly after a stroke, however, does not necessarily indicate that the patient will continue to have seizures following initial recovery. This is true even when patients present in epileptic status. This may be because early and late seizures are produced by different pathophysiologic mechanisms.

Age-related reductions in cerebral vasomotor reactivity and the law of initial value: a 4-year prospective longitudinal study

A group of 51 neurologically normal, middle-aged and elderly volunteers (aged 35-86 years; mean age 63.24 years) with and without risk factors for stroke were given annual tests of cerebral vasomotor reactivity to assess any changes in the cerebral vascular capacitance associated with advancing age that might alter cerebral vasomotor reactivity. Cerebral vasomotor reactivity was estimated as the difference in bihemisphere gray matter CBF measured by the 133Xe inhalation method in the steady state breathing room air, followed by a second measurement during inhalation of 100% oxygen. There were significant and progressive reductions in cerebral vasomotor reactivity during the 4-year longitudinal study. Positive linear correlations were apparent between initial steady-state mean bihemisphere gray matter CBF levels and degrees of vasomotor reactivity, suggesting that the Law of Initial Value plays an important role. This should be borne in mind when analyzing scores of cerebral vasomotor reactivity. In the present communication, analysis of covariance was used to correct for influences of initial CBF levels on vasomotor responses tested while breathing pure oxygen.