[The white matter of an aging person in magnetic resonance images].
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Aging↗
Biomedical subjects
T Erkinjuntti
Publications and source records attributed to T Erkinjuntti.
The prevalence and distribution of white-matter changes on different MRI pulse sequences in a post-stroke cohort.
No uniform criteria currently exist for rating white-matter (WM) high-signal foci on MRI. Ratings are based on descriptive terms, different pulse sequences and different WM areas. Reports on the prevalence and clinical correlates of high-signal foci have been contradictory. We wanted to examine the contribution of the pulse sequence and WM area on rating WM changes. We analysed WM changes separately on T2-, protondensity (PD)- and T1-weighted images in periventricular, subcortical, watershed area and deep WM. The difference between T2- and PD-weighted images was significant for frontal caps, counting small foci or analysing subcortical changes. T1-weighted images showed significantly less change, but the number of foci detected was greater than previously thought. The prevalence of WM high-signal foci was greatest in the watershed zone and smallest in the subcortical area. There was a significant correlation between foci in different areas.
Aged↗
Impaired preconscious auditory processing and cognitive functions in Alzheimer's disease.
OBJECTIVE: To study whether preconscious auditory processing is deteriorated in patients with Alzheimer's disease (AD) having mild to moderate cognitive symptoms. To investigate whether auditory processing correlates with the impairment of the higher cortical functions. METHODS: P50m and N100m responses elicited by a sequence of repetitive tones were recorded with a whole-head magnetometer from 22 patients with probable AD and from 18 healthy age-matched controls. In addition, an extensive neuropsychological test battery assessing main cognitive domains was administered to all subjects. RESULTS: The patients with AD had significantly delayed N100m responses in the left hemisphere that correlated with the impairment of the language functions. CONCLUSIONS: N100m auditory responses measured with magnetoencephalography may be useful in evaluating the severity and progression of the cortical dysfunction in dementia.
Aged↗
Heterogeneity of cognitive profiles in aging: successful aging, normal aging, and individuals at risk for cognitive decline.
Neuropsychological clinical decision-making is complicated by the fact that variability in test performance increases with advancing age. This research explores the presence of homogeneous subgroups in 120 neurologically healthy individuals, from 55 to 85 years of age. Subjects at risk for dementing diseases were diagnosed as Aging-Associated Cognitive Decline (AACD) and Mild Cognitive Impairment (MCI). Cluster analysis was applied on 11 neuropsychological variables assessing logical memory immediate recall and retention percentage, visual memory immediate recall and retention, conceptual thinking, naming, verbal fluency, constructional functions, motor speed, flexibility and finger tapping. Five clusters were extracted, one representing cognitively successfully aged, and two consisting of individuals with normal or average level of performance. One cluster was characterized by older subjects with difficulties in visual memory, visuoconstructional functions, and speed and attention, most of the younger subjects in the same cluster had a diagnosis of AACD or MCI. The fifth cluster represented individuals at risk for dementing diseases; most of them were diagnosed having AACD and more than half had a diagnosis of MCI. Age, activity and intellectual levels, and to a lesser degree education, were significantly related to the cluster solution. The present findings caution against treating samples of elderly individuals as homogeneous.
Age Factors↗
Executive functions and speed of mental processing in elderly patients with frontal or nonfrontal ischemic stroke.
Impairments in executive functions have been related to aging and frontal lobe lesions. Aging also causes slowing of mental processing. We examined whether ischemic stroke in the frontal brain area results in dysexecutive syndrome, or whether the frontal stroke causes increased slowing of mental processing. Neurological, radiological and neuropsychological examinations were carried out 3 months post-stroke on 250 ischemic stroke patients (55-85 years) and on 39 healthy control subjects. Of the patients, 62 had frontal and 188 had nonfrontal lesions. The neuropsychological examination comprised several cognitive domains, including tests considered to measure executive functions. The frontal group was slower than the nonfrontal group in tasks measuring speed of mental processing which were time-limited (Trail Making A, Stroop dots and fluency). They were also inferior in the Digit Span backwards task. There were no differences between the groups in other cognitive domains, nor in some tests which are considered to be measures of executive functions (e.g. WCST). Impairments in executive functions were evident in both the frontal and the nonfrontal groups compared with the controls, but no dysexecutive syndrome specifically related to frontal lesions was found. Frontal stroke related mainly to the slowing of mental processing.
Age Factors↗
Clinical and radiological determinants of prestroke cognitive decline in a stroke cohort.
OBJECTIVES: Stroke seems to be related to dementia more often than previously assumed and vascular factors are also related to Alzheimer's disease. The pathophysiology of poststroke dementia includes ischaemic changes in the brain, a combination of degenerative and vascular changes, and changes only related to Alzheimer's disease. Some cognitive decline recognised after a stroke may be due to pre-existing cognitive decline. The aim of this study was to determine the clinical and radiological determinants of prestroke cognitive decline. METHODS: The study group comprised 337 of 486 consecutive patients aged 55 to 85 years who 3 months after ischaemic stroke completed a comprehensive neuropsychological test battery; structured medical, neurological, and mental status examination; interview of a knowledgeable informant containing structured questions on abnormality in the cognitive functions; assessment of social functions before the index stroke; and MRI. RESULTS: Frequency of prestroke cognitive decline including that of dementia was 9.2% (31/337). The patients with prestroke cognitive decline were older, more often had less than 6 years of education, and had history of previous stroke. Vascular risk factors did not differ significantly between these two groups. White matter changes (p=0.004), cortical entorhinal, hippocampal, and medial temporal atrophy (p<0.001), cortical frontal atrophy (p=0.008); and any central atrophy (p<0.01), but not the frequencies or volumes of old, silent, or all infarcts on MRI differentiated those with and without prestroke cognitive decline. The correlates of prestroke cognitive decline in logistic regression analysis were medial temporal cortical atrophy (odds ratio (OR) 7.5, 95% confidence interval (95%CI) 3.2-18.2), history of previous ischaemic stroke (OR 4.4, 95% CI 1.8-10.6), and education (OR 0.9, 95% CI 0.8-0.9). CONCLUSIONS: History of previous stroke, but not volumes or frequencies was found to correlate with prestroke cognitive decline. Other associating factors were rather those usually associated with degenerative dementia: white matter changes and cerebral atrophy; and in multiple models medial temporal cortical atrophy and education. The possible overlap between two or more underlying diseases must be remembered in diagnosis and treatment of patients with vascular cognitive impairment.
Aged↗
White matter changes in stroke patients. Relationship with stroke subtype and outcome.
White matter changes (WMC), detected by imaging techniques, are frequent in stroke patients. The aim of the study was to determine how WMC relate to stroke subtypes and to stroke outcome. We made a systematic Medline search for articles appearing with two of the following key words: either 'WMC or white matter lesions or leukoencephalopathy or leukoaraiosis' and 'stroke or cerebral infarct or cerebral hemorrhage or cerebrovascular disease or transient ischemic attack (TIA)'. WMC, as defined radiologically, are present in up to 44% of patients with stroke or TIA and in 50% of patients with vascular dementia. WMC are more frequent in patients with lacunar infarcts, deep intracerebral hemorrhages, cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy and cerebral amyloid angiopathy. After an acute ischemic stroke, WMC are associated with a higher risk of death or dependency, recurrent stroke of any type, cerebral bleeding under anticoagulation, myocardial infarction, and poststroke dementia. WMC in stroke patients are often associated with small-vessel disease and lead to a higher risk of death, and poor cardiac and neurological outcome. However, several questions remain open and need further investigations.
Age Factors↗
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.
Aged↗
Rapid apolipoprotein E genotyping from mailed buccal swabs.
Genetic polymorphism of apolipoprotein E (apoE) is linked with the risk of cardiovascular and Alzheimer's disease (AD). We determined apoE genotypes from mailed buccal cell swabs in 36 healthy individuals and 18 demented patients suffering from AD. DNA was released from the swabs by a rapid lysis technique. Polymerase chain reaction using 'hot start' and restriction enzyme digestion by HhaI was used for genotyping of apoE alleles, which were detected by polyacrylamide or MetaPhor agarose gel. ApoE genotypes determined from buccal cells or from stored leucocytes were identical to previously done phenotyping. An advantage of the present simplified buccal cell collection procedure is the possibility to collect DNA samples for apoE genotyping rapidly by mail from patients visiting their physician geographically distant from research laboratory. Moreover, venepuncture and storing of the samples in refrigerators are avoided and costs are reduced. This non-invasive and painless method is also applicable to other genetic screening tests in risk populations.
Adult↗
Serum total cholesterol, apolipoprotein E epsilon 4 allele, and Alzheimer's disease.
The epsilon 4 allele of the apolipoprotein E (apoE) is associated with Alzheimer's disease (AD) and also with elevated serum total cholesterol and low-density lipoprotein levels. However, the interrelationships between apoE genotype, plasma cholesterol levels and AD risk have been studied very little. We examined the possible role of serum total cholesterol in the pathogenesis of AD in a population-based sample of 444 men, aged 70-89 years, who were survivors of the Finnish cohorts of the Seven Countries Study. Previous high serum cholesterol level (mean level > or = 6.5 mmol/l) was a significant predictor of the prevalence of AD (odds ratio = 3.1; 95% confidence interval = 1.2, 8.5) after controlling for age and the presence of apoE epsilon 4 allele. In men who subsequently developed AD the cholesterol level decreased before the clinical manifestations of AD. We conclude that high serum total cholesterol may be an independent risk factor for AD and some of the effect of the apoE epsilon 4 allele on risk of AD might be mediated through high serum cholesterol.
Adult↗
Propentofylline in the treatment of Alzheimer's disease and vascular dementia: a review of phase III trials.
Propentofylline, a neuroprotective glial cell modulator, has been shown in preclinical studies to address some of the common pathological processes of Alzheimer's disease (AD) and vascular dementia (VaD), including glial cell activation and increased production of cytokines, free radicals, and glutamate. To examine whether propentofylline (300 mg t.i.d. taken 1 h before meals) would provide beneficial effects in patients with AD and/or VaD, 901 patients with mild-to-moderate AD and 359 patients with mild-to-moderate VaD were enrolled in four double-blind, placebo-controlled, randomized studies ranging in duration from 6 months to 56 weeks. Propentofylline was found to provide consistent improvements over placebo in efficacy assessments for both AD and VaD patients. In addition, results from a drug withdrawal study suggested that propentofylline does not merely relieve dementia symptoms but slows the progression of the disease itself. Propentofylline had a good safety profile and was generally well tolerated.
Alzheimer Disease↗
Cooperation and networking on white matter disorders: the European Task Force on Age-Related White Matter Changes.
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Communication↗
Clinical determinants of poststroke dementia.
BACKGROUND AND PURPOSE: Frequency of poststroke dementia is high, and stroke considerably increases the risk of dementia. The risk factors for dementia related to stroke are still incompletely understood. We sought to examine clinical determinants of poststroke dementia in a large well-defined stroke cohort. METHODS: The study group comprised 337 of 486 consecutive patients aged 55 to 85 years who 3 months after ischemic stroke completed a comprehensive neuropsychological test battery and MRI, including structured medical, neurological, and laboratory evaluations; clinical mental status examination; interview of a knowledgeable informant; detailed history of risk factors; and evaluation of stroke type, localization, and syndrome. The DSM-III definition for dementia was used. RESULTS: Frequency of any poststroke dementia was 31.8% (107/337), that of stroke-related dementia (mixed Alzheimer's disease plus vascular dementia excluded) was 28.4% (87/306), and that of dementia after first-ever stroke was 28.9% (79/273). The patients with poststroke dementia were older and more often had a low level of education, history of prior cerebrovascular disease and stroke, left hemispheric stroke (reflecting laterality), major dominant stroke syndrome (reflecting laterality and size), dysphasia, gait impairment, and urinary incontinence. The demented patients were also more frequently current smokers, had lower arterial blood pressure values, and more frequently had an orthostatic reaction compared with the nondemented stroke patients. The correlates of dementia in logistic regression analysis were dysphasia (odds ratio [OR], 5.6), major dominant stroke syndrome (OR, 5.0), history of prior cerebrovascular disease (OR, 2.0), and low educational level (OR, 1.1). When we excluded those with cerebrovascular disease plus Alzheimer's disease or those with recurrent stroke, the order of correlates remained the same. When the patients with dysphasia (n=30) were excluded, the correlates were major dominant syndrome (OR, 4.6) and low educational level (OR, 1.1). CONCLUSIONS: Our data suggest that a single explanation for poststroke dementia is not adequate; rather, multiple factors including stroke features (dysphasia, major dominant stroke syndrome), host characteristics (educational level), and prior cerebrovascular disease each independently contribute to the risk.
Age Factors↗
Frequency and clinical determinants of poststroke depression.
BACKGROUND AND PURPOSE: Previous studies have shown a large variation concerning the frequency of poststroke depression. This variation is caused by differences in patient populations, psychiatric assessment methods, and diagnostic criteria. In this study, we evaluated the frequency and clinical correlates of poststroke depression in a large well-defined stroke cohort. METHODS: We studied a consecutive series of 486 patients with ischemic stroke aged from 55 to 85 years. Of these, 277 patients underwent a comprehensive psychiatric evaluation, including the Present State Examination, from 3 to 4 months after ischemic stroke. The criteria of the Diagnostic and Statistical Manual of Mental Disorders, edition 3, revised (DSM-III-R), were used for the diagnosis of depressive disorders. RESULTS: The frequency of any depressive disorder was 40.1% (n=111). Major depression was diagnosed in 26.0% (n=72) and minor depression in 14.1% (n=39). Major depression with no other explanatory factor besides stroke was diagnosed in 18.0% (n=49) of the patients. Comparing depressed and nondepressed patients, we found no statistically significant difference in sex, age, education, stroke type, stroke localization, stroke syndrome, history of previous cerebrovascular disease, or frequency of DSM-III-R dementia. According to the multiple logistic regression model, dependency in daily life correlated with the diagnosis of depression (odds ratio [OR], 1.8; 95% confidence interval [CI], 1.1 to 3.1) and with the diagnosis of major depression (OR, 2.9; 95% CI, 1.6 to 5.5). A history of previous depressive episodes also correlated with the diagnosis of depression (OR, 2.3; 95% CI, 1.3 to 4.4) and with the diagnosis of major depression (OR, 2.9; 95% CI, 1.6 to 5.5), whereas solely stroke-related major depression correlated only weakly with stroke severity as measured on the Scandinavian Stroke Scale (OR, 1.1; 95% CI, 1.0 to 1.1). CONCLUSIONS: Clinically significant depression is frequent after ischemic stroke. We emphasize the importance of the psychiatric examination of poststroke patients, especially those with a significant disability and with a history of prior depressive episodes.
Aged↗
Propentofylline in the treatment of vascular dementia and Alzheimer-type dementia: overview of phase I and phase II clinical trials.
Pathophysiologic processes common to both vascular (multi-infarct) dementia and dementia of the Alzheimer type may include microglial activation with resultant generation of inflammatory cytokines and neurotoxic free radicals, decreased secretion of nerve growth factor by astrocytes, excess release of glutamate with associated neurotoxicity, and loss of cholinergic neurons. The functional benefits and neuroprotective effects of propentofylline (PPF) stem from its interference with these overlapping pathways of neurodegeneration. The clinical pharmacology and safety of PPF were studied in a number of phase I studies in healthy young and elderly adults and in patients with renal or hepatic impairment. These studies have shown that PPF 300 mg t.i.d. is safe and well tolerated when taken on an empty stomach 1 h before meals. In a randomized, double-blind phase II study involving 190 elderly subjects with clinically and psychometrically documented mild to moderate dementia, 12 weeks of PPF therapy produced significantly greater improvements than placebo in Gottfries-Bråne-Steen (GBS) scores, Mini-Mental State Examination (MMSE) scores, and Clinical Global Impression (CGI) ratings. A subsequent phase II study using positron emission tomography (PET) revealed that cortical glucose metabolism improved significantly in patients with vascular dementia after 12 weeks of PPF treatment but deteriorated significantly with placebo. A third phase II study, which enrolled patients with Alzheimer-type dementia, demonstrated that PPF significantly enhanced functional reserve, as reflected by increases in regional cerebral glucose metabolism after stimulation with a verbal memory task. In contrast, patients randomized to placebo exhibited a significant decline in functional activation and significant worsening in their MMSE scores over the course of this 12-week study. Propentofylline proved to be safe, well tolerated, and free of severe side effects in all three of these phase II trials. Phase I trial results suggest that significant food interactions occur with PPF, indicating that the drug should be taken on an empty stomach 1 h before meals. Phase II trial results indicate that PPF yields clinically measurable improvements in the symptoms of dementia and prevents loss of stimulation-related increases in glucose metabolism over a treatment period of 3 months. Whether these results indicate that PPF can slow the progression of dementia can be determined only by long-term trials specifically designed to determine the drug's effect on disease progression.
Aged↗
The effect of different diagnostic criteria on the prevalence of dementia.
BACKGROUND: There are several widely used sets of criteria for the diagnosis of dementia, but little is known about their degree of agreement and their effects on estimates of the prevalence of dementia. METHODS: We examined 1879 men and women 65 years of age or older who were enrolled in the Canadian Study of Health and Aging and calculated the proportion given a diagnosis of dementia according to six commonly used classification systems: the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders (DSM), third edition (DSM-III), the third edition, revised of the DSM (DSM-III-R), the fourth edition of the DSM (DSM-IV), the World Health Organization's International Classification of Diseases (ICD), 9th revision (ICD-9) and 10th revision (ICD-10), and the Cambridge Examination for Mental Disorders of the Elderly (CAMDEX). The degree of concordance among classification schemes and the importance of various factors in determining diagnostic agreement or disagreement were examined. RESULTS: The proportion of subjects with dementia varied from 3.1 percent when we used the criteria of the ICD-10 to 29.1 percent when the DSM-III criteria were used. The six classification systems identified different groups of subjects as having dementia; only 20 subjects were given a diagnosis of dementia according to all six systems. The classifications based on the various systems differed little according to the patients' age, sex, educational level, or status with respect to institutionalization. The factors that most often caused disagreement in diagnosis between DSM-III and ICD-10 were long-term memory, executive function, social activities, and duration of symptoms. CONCLUSIONS: The commonly used criteria for diagnosis can differ by a factor of 10 in the number of subjects classified as having dementia. Such disagreement has serious implications for research and treatment, as well as for the right of many older persons to drive, make a will, and handle financial affairs.
Aged↗
Serum protein leakage in Alzheimer's disease revisited.
Leakage of serum proteins into the brain parenchyma has been repeatedly used as evidence of blood-brain barrier (BBB) damage in experimental and human studies. However, there is no consensus in the literature concerning this phenomenon in Alzheimer's disease (AD). We have examined this question by comparing frontal lobe sections in seven groups of patients: Multi-infarct dementia (n = 6), AD with (n = 10) and without (n = 10) infarcts, age-matched controls with (n = 10) and without (n = 10) infarcts, controls with neurodegenerative diseases other than AD, and young controls (n = 10). An additional series compared prospectively followed patients with a diagnosis of either multi-infarct dementia (n = 5) or AD (n = 4). Albumin was detected in white-matter astrocytes in all cases, without significant variation in intensity. In addition, diverse combinations of neurons, astrocytes, and (in AD patients) senile plaques were present in the cerebral cortex in an inconsistent manner. Semiquantitative analysis showed no statistically significant differences among groups. Anti-IgG labeled astrocytes in infarcts only. Complement C3c component was detected in rare amyloid plaques in a minority (15%) of AD cases. Selective labeling of AD-specific lesions in a patchy manner was observed for serum amyloid P. We conclude that there is no immunohistochemical evidence of alteration of the BBB in Alzheimer's disease with or without vascular factors or in old age. Serum amyloid P binds avidly to AD lesions, but our findings are consistent with leakage through the BBB during the agonal or immediate postmortem period. Finally, no specific pattern of abnormality in the BBB was detected in multi-infarct dementia.
Alzheimer Disease↗
Misclassification of dementia subtype using the Hachinski Ischemic Score: results of a meta-analysis of patients with pathologically verified dementias.
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Cerebral Infarction↗