Leuko-araiosis and stroke: a case-control study

Population-based case-control study of white matter changes on brain imaging in transient ischemic attack and ischemic stroke

BACKGROUND AND PURPOSE

White matter changes (WMC) are a common finding on brain imaging and are associated with an increased risk of ischemic stroke. They are most frequent in small vessel stroke; however, in the absence of comparisons with normal controls, it is uncertain whether WMC are also more frequent than expected in other stroke subtypes. Therefore, we compared WMC in pathogenic subtypes of ischemic stroke versus controls in a population-based study.

METHODS

We evaluated the presence and severity of WMC on computed tomography and on magnetic resonance brain imaging using modified Blennow/Fazekas scale and age-related white matter changes scale, respectively, in a population-based study of patients with incident transient ischemic attack or ischemic stroke (Oxford Vascular Study) and in a study of local controls (Oxford Project to Investigate Memory and Ageing) without history of transient ischemic attack or ischemic stroke, with stratification by stroke pathogenesis (Trial of Org10172 in Acute Stroke Treatment classification).

RESULTS

Among 1601 consecutive eligible patients with first-ever ischemic events, 1453 patients had computed tomography brain imaging, 562 had magnetic resonance imaging, and 414 patients had both. Compared with 313 controls (all with computed tomography and 131 with magnetic resonance imaging) and after adjustment for age, sex, diabetes mellitus, and hypertension, moderate/severe WMC (age-related white matter changes scale) were more frequent in patients with small vessel events (odds ratio, 3.51 [95% confidence interval, 2.13-5.76]; P<0.0001) but not in large artery (odds ratio, 1.03 [95% confidence interval, 0.64-1.67]), cardioembolic (odds ratio, 0.87 [95% confidence interval, 0.56-1.34]), or undetermined (odds ratio, 0.90 [95% confidence interval, 0.62-1.30]) subtypes. Results were consistent for ischemic stroke and transient ischemic attack, for other scales, and for magnetic resonance imaging and computed tomography separately.

CONCLUSIONS

In contrast to small vessel ischemic events, WMC were not independently associated with other pathogenic subtypes, suggesting that WMC are unlikely to be an independent risk factor for nonsmall vessel events.

Seventh report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure

The National High Blood Pressure Education Program presents the complete Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure. Like its predecessors, the purpose is to provide an evidence-based approach to the prevention and management of hypertension. The key messages of this report are these: in those older than age 50, systolic blood pressure (BP) of greater than 140 mm Hg is a more important cardiovascular disease (CVD) risk factor than diastolic BP; beginning at 115/75 mm Hg, CVD risk doubles for each increment of 20/10 mm Hg; those who are normotensive at 55 years of age will have a 90% lifetime risk of developing hypertension; prehypertensive individuals (systolic BP 120-139 mm Hg or diastolic BP 80-89 mm Hg) require health-promoting lifestyle modifications to prevent the progressive rise in blood pressure and CVD; for uncomplicated hypertension, thiazide diuretic should be used in drug treatment for most, either alone or combined with drugs from other classes; this report delineates specific high-risk conditions that are compelling indications for the use of other antihypertensive drug classes (angiotensin-converting enzyme inhibitors, angiotensin-receptor blockers, beta-blockers, calcium channel blockers); two or more antihypertensive medications will be required to achieve goal BP (<140/90 mm Hg, or <130/80 mm Hg) for patients with diabetes and chronic kidney disease; for patients whose BP is more than 20 mm Hg above the systolic BP goal or more than 10 mm Hg above the diastolic BP goal, initiation of therapy using two agents, one of which usually will be a thiazide diuretic, should be considered; regardless of therapy or care, hypertension will be controlled only if patients are motivated to stay on their treatment plan. Positive experiences, trust in the clinician, and empathy improve patient motivation and satisfaction. This report serves as a guide, and the committee continues to recognize that the responsible physician's judgment remains paramount.

Hypertension and clusters of risk factors in different stroke subtypes (an analysis of Hungarian patients via Budapest Stroke Data Bank)

Our aim was to determine the frequency of hypertension in the Hungarian stroke population, and to compare it with the data of other stroke registries. We attempted to find characteristic cluster-like associations between hypertension and another nine risk factors in different stroke subtypes and to ascertain the role of hypertension in leukoaraiosis, in early mortality, in stroke recurrence and in the case fatality rate up to 10 years. Risk factor profile of 500 unselected acute stroke cases of the Budapest Stroke Data Bank were analysed. We compared data of hypertensive stroke patients to those of unaffected ones. LIFEREG procedure of the SAS software package, cluster analysis, logistic regression, Pearson's correlation coefficient and Student's t-test were used as statistical methods. Hypertension was documented in 75% of the patients. The largest clusters were formed by the following groups: atherosclerotic stroke, hypertension with ischaemic heart disease; lacunar stroke and haemorrhage, hypertension with elevated serum cholesterol, cardiogenic embolism, ischaemic heart disease with atrial fibrillation. The case fatality rate was significantly higher in the group of hypertensive patients with ischaemic heart disease relative to those without it during the 10 years follow-up period. In the leukoaraiosis-group, systolic blood pressure was significantly higher than in the non-leukoaraiosis group. The rate of hypertension was higher than in other stroke registries. Hypertension appears to be the most frequent risk factor in stroke patients but case fatality rate is determined by presence or absence of ischaemic heart disease.

Magnetic resonance imaging white matter hyperintensities and mechanism of ischemic stroke

BACKGROUND AND PURPOSE

We sought to determine the relations between infarct subtype and white matter hyperintensities (WMHIs) on MRI.

MATERIALS AND METHODS

We studied 395 ischemic stroke patients with 1. 0-T MRI. The number of lacunar, border-zone, and cortical infarcts was registered. WMHIs were analyzed in 6 areas. Univariate and multivariate statistical analyses were used to find the risk factors for different infarct subtypes and to study the connections between WMHIs and brain infarcts.

RESULTS

Lacunar infarcts were associated with hypertension (odds ratio [OR], 1.79; 95% CI, 1.17 to 2.73), alcohol consumption (OR, 1.96; 95% CI, 1.17 to 3.28), and age (OR, 1. 03; 95% CI, 1.00 to 1.06). Border-zone infarcts were associated with carotid atherosclerosis (OR, 2.20; 95% CI, 1.15 to 4.19). Atrial fibrillation (OR, 3.02; 95% CI, 1.66 to 5.50) and carotid atherosclerosis (OR, 1.94; 95% CI, 1.12 to 3.36) were independent positive predictors, and history of hyperlipidemia (OR, 0.44; 95% CI, 0.26 to 0.75) and migraine (OR, 0.48; 95% CI, 0.25 to 0.93) were negative predictors for cortical infarcts. Patients with lacunar infarcts had more severe WMHIs than patients with nonlacunar infarcts in all WM areas (P</=0.001). Patients with border-zone infarcts showed severe periventricular lesions (P=0.002), especially around posterior horns (P=0.003). The extent of WMHIs in patients with cortical infarcts did not differ from that in those without cortical infarcts.

CONCLUSIONS

Various infarct subtypes have different risk profiles. The association between lacunar infarcts and WMHIs supports the concept of small-vessel disease underlying these 2 phenomena. The connection between border-zone infarcts and periventricular WMHIs again raises the question of the disputed periventricular vascular border zone.

Late epileptic seizures after cerebral infarction

OBJECTIVES

To determine the profile of late epileptic seizures following cerebral infarcts and the predictive clinical and radiological factors associated with their development.

METHODS

We compared 86 patients who developed late seizures after cerebral infarction with 285 similar patients who did not develop seizures for at least 1 year after their stroke. Patients who had seizures only at the onset of the stroke were excluded. Odds' ratios were used for statistical analysis.

RESULTS

Simple partial, and mainly motor seizures, with or without secondary generalization, accounted for 80% of the classifiable seizures but it was not possible to determine the seizure type in half of the cases. Factors that appeared to be predictive of seizure development were the presence of large cortical infarcts and the presence of apparently preserved cerebral tissue within the infarcted area. Seizures were rare in patients with lacunar infarction but the presence of associated leukoaraiosis increased the risk. The risk was also increased in patients with other medical problems known to lower seizure threshold, such as renal failure.