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A Heyman

Publications and source records attributed to A Heyman.

At least 55 records · Page 3Linked to original sources

Magnetic resonance findings in patients with early-onset Alzheimer's disease.

The magnetic resonance scans of 22 patients with early-onset Alzheimer's disease (AD) were compared to 16 age-matched neurologically normal controls for the presence of white matter subcortical hyperintensities (SCH) and periventricular hyperintensities (PVH). Patients with AD were significantly more likely to have evidence of PVH (p less than 0.01) than age-matched controls. There was no significant difference between the two groups in either the frequency of SCH or the size of the largest lesion. Within the AD group, there was no difference demonstrated in the location of the SCH, either in the anterior-posterior plane or between the two hemispheres. Patients with AD more frequently demonstrated ventriculomegaly (p less than 0.001) and sulcal widening (p less than 0.05) compared with controls. This study suggests that the SCH seen in early-onset AD patients on MRI are related more to the aging process than to the AD process and that the increased frequency of PVH may have a relationship to the disease process.

Aged↗

Detection of abnormal memory decline in mild cases of Alzheimer's disease using CERAD neuropsychological measures.

The present study was designed to determine which of the memory tasks included in the CERAD (Consortium to Establish a Registry for Alzheimer's Disease) neuropsychological battery best differentiate patients with early Alzheimer's disease from cognitively normal elderly control subjects and also best distinguish between the various levels of severity of the dementia process. A sample of CERAD patients with Alzheimer's disease was stratified by disease severity into those with mild, moderate, or severe dementia and matched with control subjects for sex, age, and education. Using multivariate procedures and cutting scores, the efficacy of each memory measure in distinguishing between these groups and control subjects was determined. The test for delayed recall was found to be the best overall discriminatory measure. The other tests of memory, ie, immediate recall, intrusion errors, and recognition memory, had poor overall discriminability. None of the CERAD memory measures were found to be particularly powerful in staging the severity of dementia. These findings suggest that tests for delayed recall may be particularly useful in the early detection of Alzheimer's disease and should be considered in screening batteries for dementia in community surveys.

Aged↗

Estimated prevalence of dementia among elderly black and white community residents.

A stratified random sample of 83 black and 81 white community residents aged 65 years and older in a five-county area in the Piedmont region of North Carolina was evaluated for dementia, using the Diagnostic and Statistical Manual of Mental Disorders, Third Edition, and the National Institute of Neurological Disorders and Stroke--Alzheimer's Disease and Related Disorders Association criteria. Of 164 subjects, 26 were found to be demented, resulting in an estimated prevalence rate of dementia in the five-county area of 16% (95% confidence interval, 7.92 to 24.08) for blacks and 3.05% (95% confidence interval, 0 to 6.91) for whites. The estimated prevalence of dementia for white women (2.9%) was similar to that for white men (3.3%), but the rate for black women was distinctly higher than for black men (19.9% and 8.9%, respectively). Blacks were more likely than whites to have a history of stroke, hypertension, and other chronic disorders that might have contributed to the development of dementia. Apart from differences in rates of institutionalization, no other relevant factors were identified that might explain the difference in the prevalence of dementia in these black and white community residents.

Black or African American↗

Familial aggregation of Alzheimer's disease and related disorders: a collaborative re-analysis of case-control studies.

Case-control studies of Alzheimer's disease were re-analysed to examine the association of Alzheimer's disease with family history in first degree relatives of dementia, Down's syndrome and Parkinson's disease. Overall, the relative risk of Alzheimer's disease for those with at least one first degree relative with dementia was 3.5 (95% confidence interval 2.6-4.6). Stratification according to age of onset of Alzheimer's disease showed that the relative risk decreased with increasing onset age. However, among patients with an onset of disease after 80 years, there were still significantly more subjects with one or more first degree relatives with dementia as compared to controls (relative risk 2.6; 95% confidence interval 1.3-5.2). The relative risk of Alzheimer's disease was significantly lower in patients who had one first degree relative with dementia (relative risk 2.6; 95% confidence interval 2.0-3.5) as compared to those who had two or more affected relatives (relative risk 7.5; 95% confidence interval 3.3-16.7). Furthermore, the re-analysis showed a significant association between Alzheimer's disease and family history of Down's syndrome (relative risk 2.7; 95% confidence interval 1.2-5.7), which was strongest in those patients who had a positive family history of dementia. The relative risk of Alzheimer's disease for those with a positive family history of Parkinson's disease was 2.4 (95% confidence interval 1.0-5.8).

Age Factors↗

Maternal age and Alzheimer's disease: a collaborative re-analysis of case-control studies. EURODEM Risk Factors Research Group.

To investigate the possible association between Alzheimer's disease and late maternal age at index birth, we conducted a collaborative re-analysis of existing case-control data sets. Of the 11 studies participating in the EURODEM project, four were included in the analyses regarding maternal age. In all four studies, cases were matched to controls by age and gender, and only population controls were considered. Analyses were conducted on the individual data sets, on the pooled sample, and on subgroups defined by gender, age at onset, and familial aggregation of dementia. Maternal age of 40 years and over was found to be suggestively associated with a higher risk of Alzheimer's disease (overall relative risk = 1.7; 95% confidence intervals: 1.0-2.9). In subgroup analyses, the association was statistically significant for women and for sporadic cases. Adjustments for education or analyses restricted to case-control pairs matched by type of respondent did not modify these results noticeably. The association was confirmed by a test of consistency with the Down's syndrome risk model; results of this test were again more definite for sporadic Alzheimer's disease. In addition, three of the four studies also suggested an increased risk for maternal age at index birth between 15 and 19 years (overall relative risk = 1.5; 95% confidence intervals: 0.8-3.0). Although consistency across studies was not always complete, only some of the increased relative risks reached statistical significance, and information regarding maternal age obtained through a next-of-kin interview may have limitations, our study suggests that both early and late maternal age should be further investigated as possible risk factors for Alzheimer's disease.

Adolescent↗

Head trauma as a risk factor for Alzheimer's disease: a collaborative re-analysis of case-control studies. EURODEM Risk Factors Research Group.

A re-analysis of the data from 11 case-control studies was performed to investigate the association between head trauma and Alzheimer's disease (AD). To increase comparability of studies, exposures were limited to head trauma with loss of consciousness (hereafter referred to as 'head trauma') and comparisons were restricted to community (versus hospital) controls. Test for heterogeneity across studies was negative; consequently, data were pooled in subsequent analyses. The pooled relative risk for head trauma was 1.82 (95% confidence interval: 1.26-2.67). Stratified analyses showed stronger associations in cases without a positive family history of dementia and in males (versus females). Adjustment of the pooled relative risk for family history of dementia, education and alcohol consumption did not alter significantly the association between head trauma and AD. There was no interaction effect between head trauma and family history of dementia, suggesting that these risk factors operate independently. Mean age of onset was not significantly different in cases with a history of head trauma compared to cases without such a history. The findings of the pooled analysis support an association between reported head trauma and AD.

Alzheimer Disease↗

Medical history and the risk of Alzheimer's disease: a collaborative re-analysis of case-control studies. EURODEM Risk Factors Research Group.

In a re-analysis of eight case-control studies on Alzheimer's disease we explored several medical conditions that had previously been suggested as possible risk factors for Alzheimer's disease. History of hypothyroidism was increased in cases as compared to controls (relative risk 2.3; 95% confidence interval 1.0-5.4). Severe headaches and migraine were inversely related to Alzheimer's disease (relative risk 0.7; 95% confidence interval 0.5-1.0). More cases than controls reported epilepsy before onset of Alzheimer's disease (relative risk 1.6; 95% confidence interval 0.7-3.5), especially for epilepsy with an onset within 10 years of onset of dementia. Neurotropic viruses, allergic conditions, general anaesthesia and blood transfusions were not associated with Alzheimer's disease.

Alzheimer Disease↗

Psychiatric history and related exposures as risk factors for Alzheimer's disease: a collaborative re-analysis of case-control studies. EURODEM Risk Factors Research Group.

Data from case-control studies of Alzheimer's disease (AD) were pooled to examine the possible roles of history of depression, anti-depressant treatment and adverse life events as risk factors. History of depression was found to be associated with AD, although the effect was confined to late onset cases. The association held for episodes of depression more than 10 years before AD onset, as well as for episodes occurring within a decade of onset. No association was found with anti-depressant treatment. However, data were only available from two studies, limiting the power of the analysis. Also, no association was found with the three major life events considered in the pooled analysis: death of spouse, death of a child and divorce.

Alzheimer Disease↗

Alcohol and tobacco consumption as risk factors for Alzheimer's disease: a collaborative re-analysis of case-control studies. EURODEM Risk Factors Research Group.

A meta-analysis, involving the secondary analysis of original data from 11 case-control studies of Alzheimer's disease, is presented for alcohol consumption and cigarette smoking. Five studies included in the meta-analysis of alcohol consumption. Alcohol consumption was computed in terms of average weekly intake, measured in ounces of 'pure alcohol'. This variable was categorized into tertiles to represent low, medium and high intake. Analyses showed no excess estimated risk of Alzheimer's disease for any level of alcohol intake. Smoking was analysed in three different manners: (1) lifetime prevalence of smoking (ever/never)--this included eight studies; (2) amount smoked (less than or equal to one pack per day versus more than one pack per day)--this included seven studies; and (3) pack-years--including four studies. A statistically significant inverse association between smoking and Alzheimer's disease was observed at all levels of analysis, with a trend towards decreasing risk with increasing consumption (p(trend) = 0.0003). A propensity towards a stronger inverse relation was observed among patients with a positive family history of dementia, but the difference between this group and the group with no such history was not statistically significant. Although the observed disturbance in nicotinic receptor function in Alzheimer's disease may provide an explanation for these findings, possible biases related to the selection or survival of study subjects cannot be fully ruled out at this time. Prospective, community-based studies of incident cases of Alzheimer's disease are needed to document in detail the smoking history, age of onset of disease and survival of patients and cognitively intact people by smoking status.

Alcohol Drinking↗

Occupational exposures to solvents and lead as risk factors for Alzheimer's disease: a collaborative re-analysis of case-control studies. EURODEM Risk Factors Research Group.

A meta-analysis, involving the secondary analysis of original data from 11 case-control studies of Alzheimer's disease, is presented for occupational exposures to solvents and lead. Three studies had data on occupational exposure to solvents. Among cases, 21.3% were reported to have been exposed; among controls, this figure was comparable (20.9%). This yielded a pooled matched relative risk of 0.76 (95% CI: 0.47-1.23). Four studies had data on exposure to lead. Exposure frequencies were 6.1% in cases and 8.3% in controls. This resulted in a pooled matched relative risk of 0.71 (95% CI: 0.36-1.41). The meta-analysis was particularly useful in validating negative results from individual studies and in increasing the statistical power for the analysis of lead exposure, where stratum-specific cell sizes were frequently smaller than five in individual studies. However, since exposure in the various studies was ascertained in a rather broad manner, prospective studies are recommended which focus on high-risk occupational populations and which determine the incidence of Alzheimer's disease in these and comparable unexposed populations.

Alzheimer Disease↗

The Consortium to Establish a Registry for Alzheimer's Disease (CERAD). Part II. Standardization of the neuropathologic assessment of Alzheimer's disease.

The Neuropathology Task Force of the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) has developed a practical and standardized neuropathology protocol for the postmortem assessment of dementia and control subjects. The protocol provides neuropathologic definitions of such terms as "definite Alzheimer's disease" (AD), "probable AD," "possible AD," and "normal brain" to indicate levels of diagnostic certainty, reduce subjective interpretation, and assure common language. To pretest the protocol, neuropathologists from 15 participating centers entered information on autopsy brains from 142 demented patients clinically diagnosed as probable AD and on eight nondemented patients. Eighty-four percent of the dementia cases fulfilled CERAD neuropathologic criteria for definite AD. As increasingly large numbers of prospectively studied dementia and control subjects are autopsied, the CERAD neuropathology protocol will help to refine diagnostic criteria, assess overlapping pathology, and lead to a better understanding of early subclinical changes of AD and normal aging.

Aged↗

Sensitivity and specificity of standardized screens of cognitive impairment and dementia among elderly black and white community residents.

Six standardized published measures of cognitive function were evaluated as screens of dementia in a sample of 164 (83 black, 81 white) community residents aged 65 and over selected from the Duke University EPESE (Established Populations for Epidemiologic Studies of the Elderly), a biracial cohort of 4164 residents in a five county area of piedmont North Carolina. Of these 164 persons, 26 were subsequently diagnosed as demented. The weighted data from this sample represent the estimated performance of these measures among elderly blacks and whites in a five county area. The 6 measures evaluated in this study (specificity figures for blacks precede those for whites) were (1) Orientation-Memory-Concentration Test (38%, 79%), (2) Mental Status Questionnaire (71%, 96%), (3) Mini-Mental State (58%, 94%), (4) Storandt et al. Battery (42%, 69%), (5) Iowa Battery (26%, 69%) and (6) Kendrick Cognitive Tests (92%, 97%). All but the Kendrick Cognitive Tests showed substantial sensitivity (90-100%) in detecting the presence of dementia. The specificity of the tests was particularly poor for blacks. The briefer, simpler measures tended to have greater accuracy than the longer and more complex measures. With rare exceptions, the scores obtained on these screens correlated with race and education.

Aged↗

Diabetogenic effect of nifedipine.

This case report describes a 60-year-old diabetic patient whose daily insulin requirements increased by 30 percent following nifedipine administration. Glucagon and intravenous glucose tolerance tests were performed with and without nifedipine treatment, in order to evaluate the roles of decreased pancreatic beta islet cell function and augmented insulin peripheral resistance in the diabetogenic effect of nifedipine. Insulin and calculated glucose peripheral utilization extrapolated from the glucose concentration curves were not significantly different. C-peptide levels tended to be lower with nifedipine treatment at baseline and during the glucagon tests. This may suggest that the altered glycemic control associated with nifedipine was mediated by a suppressed islet beta cell function. The effect of calcium channel-blockers upon glycemic control and the possible mechanisms involved are discussed.

Blood Glucose↗