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R Mayeux

Publications and source records attributed to R Mayeux.

At least 127 records · Page 7Linked to original sources
PubMed1995

Synergistic effects of traumatic head injury and apolipoprotein-epsilon 4 in patients with Alzheimer's disease.

The apolipoprotein-epsilon 4 allele increases the risk of Alzheimer's disease (AD), but cerebral deposition of beta-amyloid with age, a genetic mutation, or head injury may contribute to the pathogenesis of this disease. We examined the risks of AD associated with traumatic head injury and apolipoprotein-epsilon 4 in 236 community-dwelling elderly persons. A 10-fold increase in the risk of AD was associated with both apolipoprotein-epsilon 4 and a history of traumatic head injury, compared with a two-fold increase in risk with apolipoprotein-epsilon 4 alone. Head injury in the absence of an apolipoprotein-epsilon 4 allele did not increase risk. These data imply that the biological effects of head injury may increase the risk of AD, but only through a synergistic relationship with apolipoprotein-epsilon 4.

Aged↗
PubMed1995

Neuropsychological characteristics of preclinical dementia in Parkinson's disease.

The goal of this study was to characterize the changes in cognition associated with the earliest, or preclinical, stages of dementia in Parkinson's disease (PD). We administered a comprehensive neuropsychological test battery to a group of initially nondemented PD patients participating in a longitudinal community-based epidemiologic study. We used Cox proportional hazards models to assess the relative risk of incident dementia associated with baseline scores on the neuropsychological tests. Baseline performance on two verbal fluency tasks (letter fluency and category fluency) was significantly and independently associated with incident dementia. Tests of memory, orientation, abstract reasoning, naming, and constructional skill were less sensitive predictors of subsequent dementia. The neuropsychological pattern characterizing the preclinical stages of dementia in PD differed from that described previously in preclinical Alzheimer's disease. Results suggest that poor performance on tests of verbal fluency may represent a distinct characteristic of the preclinical phase of dementia in PD.

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PubMed1995

Apolipoprotein E and Alzheimer's disease: the implications of progress in molecular medicine.

We review the current status as well as the risks and benefits of a recently developed DNA test of risk for Alzheimer's disease: the apolipoprotein E genotype. While apolipoprotein E genotypes may indicate a degree of susceptibility, the gene is neither necessary nor sufficient to cause the disease; thus, many questions remain. Because risk prediction is not straightforward, practical issues related to the testing of complex diseases like Alzheimer's and to the ethical, legal, and social implications of genetic tests require careful consideration and unambiguous answers. The use of apolipoprotein E genotyping in patients with Alzheimer's disease should be limited to research centers, and additional studies are strongly recommended. Apolipoprotein E genotypes should not be available to third parties such as insurers or employers until genotypic risks are fully understood. National policies that encourage scientific investigation while maintaining individual privacy and limiting unnecessary access to genetic information should be immediately developed.

Alzheimer Disease↗
PubMed1994

Increased risk of Alzheimer's disease in mothers of adults with Down's syndrome.

Most adults with Down's syndrome (DS) develop neuropathology characteristic of Alzheimer's disease (AD) by the age of 40. Most of the non-dysjunction events in DS are of maternal origin. We postulated therefore that a shared genetic susceptibility to DS and AD would be associated with an increased frequency of AD among mothers, but not fathers, of individuals with DS. We further hypothesised that the shared susceptibility could involve an accelerated ageing process, leading to the birth of a child with DS to a relatively young mother and to an increased risk of dementia in the mother and her relatives. Families of 96 adults with DS and of 80 adults with other forms of mental retardation were ascertained through the New York State Developmental Disabilities services network. A semi-structured interview was used to obtain information on the presence or absence of non-stroke-related dementia and other disorders in parents. There was an increase in risk of dementia among mothers of DS probands compared with control mothers (risk ratio 2.6 [95% CI 0.9-7.3]). The risk of dementia among mothers who were 35 or younger when their DS children were born was 5 times that of control mothers (4.9 [1.6-15.4]). There was no increase in risk of dementia among mothers who were older (> 35 years) at the proband's birth (0.8 [0.2-3.4]). There was no difference in risk of dementia between fathers of DS cases and fathers of controls (1.2 [0.4-3.9]) and no discernible influence of age on this risk. Familial aggregation of dementia among mothers of adults with DS supports the hypothesis of a shared genetic susceptibility to DS and AD.

Adult↗
PubMed1994

Influence of education and occupation on the incidence of Alzheimer's disease.

OBJECTIVE: Several cross-sectional studies have found an association between Alzheimer's disease (AD) and limited educational experience. It has been difficult to establish whether educational experience is a risk factor for AD because educational attainment can influence performance on diagnostic tests. This study was designed to determine whether limited educational level and occupational attainment are risk factors for incident dementia. DESIGN: Cohort incidence study. SETTING: General community. PARTICIPANTS: A total of 593 nondemented individuals aged 60 years or older who were listed in a registry of individuals at risk for dementia in North Manhattan, NY, were identified and followed up. INTERVENTIONS: We reexamined subjects 1 to 4 years later with the identical standardized neurological and neuropsychological measures. MAIN OUTCOME MEASURES: Incident dementia. RESULTS: We used Cox proportional hazards models, adjusting for age and gender, to estimate the relative risk (RR) of incident dementia associated with low educational and occupational attainment. Of the 593 subjects, 106 became demented; all but five of these met research criteria for AD. The risk of dementia was increased in subjects with either low education (RR, 2.02; 95% confidence interval [Cl], 1.33 to 3.06) or low lifetime occupational attainment (RR, 2.25; 95% Cl, 1.32 to 3.84). Risk was greatest for subjects with both low education and low life-time occupational attainment (RR, 2.87; 95% Cl, 1.32 to 3.84). CONCLUSIONS: The data suggest that increased educational and occupational attainment may reduce the risk of incident AD, either by decreasing ease of clinical detection of AD or by imparting a reserve that delays the onset of clinical manifestations.

Aged↗
PubMed1994

Interrater reliability of the Unified Parkinson's Disease Rating Scale motor examination.

Interrater reliability of the Unified Parkinson's Disease Rating Scale (UPDRS) motor examination was assessed by three neurologists experienced in the administration of this scale. Intraclass correlation coefficients indicated good-to-excellent agreement for speeded repeated movements, resting tremor, arising from a chair, and gait; moderate agreement for action tremor, rigidity, posture, postural stability, and bradykinesia; and poor agreement for speech disorder and facial immobility. Overall, these results indicate that satisfactory interrater reliability is attainable with the UPDRS motor examination.

Adult↗
PubMed1994

Smoking and Parkinson's disease.

Smoking was examined in relation to Parkinson's disease (PD) in a population-based study in northern Manhattan (New York City) because of its putative "protective effect." Using a case-control design, information on smoking and associated behaviors was obtained in structured interviews after standard diagnostic evaluations in both cases and controls. The overall prevalence of smoking in the population was 43.7%, decreasing to 37% after age 85. Smoking was most frequent in men, Blacks, and in both cases and controls using alcohol once per week or more. Cases had quit smoking more often than controls (87 vs. 64%), and had smoked for significantly fewer years (31 vs. 41 yrs; p < 0.05 for both). The age-at-onset for smokers with PD was similar to age-at-onset for nonsmokers with PD. The odds ratio (OR) for a history of smoking associated with PD was 1.1 (95% CI 0.7-1.8). No protective gradient was associated with heavier smoking patterns. However, the odds that patients with PD were still smoking at the time of the interview were significantly less than those for controls (OR = 0.2; 95% CI 0.1-0.5). These results do not support the hypothesis that smoking protects against PD; rather they strongly imply the converse, that PD reduces smoking.

Aged↗
PubMed1994

Reliability of symptom onset assessment in Parkinson's disease.

Test-retest reliability of onset date and type of initial symptoms of Parkinson's disease (PD) was assessed in 45 patients with PD who were drawn from a community-dwelling cohort in New York City. Patients were the sole information providers on both rating occasions. Reliability of symptom-onset data was found to be high, even when the interval between test and retest was up to 3 years and when the information was elicited by different neurologists. However, these patients were less consistent about the type of early symptoms. When interpreting their own disease history, patients with PD may attach more importance to when their disease began than to how it began.

Cohort Studies↗
PubMed1994

WAIS-R subtest profile and cortical perfusion in Alzheimer's disease.

WAIS-R profiles were investigated in 28 Alzheimer's disease (AD) and 21 healthy elderly subjects. The Fuld subtest profile, previously reported to have potential as a diagnostic marker for AD, was observed in 35.7% of our AD patients and 4.8% of the controls. We compared AD patients with the Fuld profile (ADF+) to a group of patients without the profile (ADF-) with similar demographics and dementia severity and demographically matched normals using regional Cerebral Blood Flow. Both AD groups showed reduced blood flow in the parietotemporal cortex compared to normals, but the ADF+ patients had greater flow reductions than the ADF- group. Examination of WAIS-R performance indicated that the ADF+ group had lower scores than the ADF- patients on the Digit Symbol and Block Design subtests, and further, that these two subtests were associated with the parietotemporal perfusion deficit in our AD sample. Our findings do not support the use of the Fuld profile as a diagnostic marker for AD, but do provide physiological evidence for behavioral heterogeneity among AD patients based on WAIS-R subtest performance.

Aged↗
PubMed1994

Alzheimer's disease.

Alzheimer's disease is the most important cause of dementia, but its cause remains unknown. Amyloid plays a dominant role in many current theories of the pathogenesis, although it is still not clear if its deposition is the trigger or the result of other processes causing cell death. An association between sporadic and familial late-onset Alzheimer's disease and polymorphisms of apolipoprotein E located on chromosome 19 suggests a new genetic model of this condition. Head trauma and substandard education have been consistently associated with increased risk, whereas the use of anti-inflammatory agents may reduce the risk of developing Alzheimer's disease. Functional imaging may have developed to the point of making an important contribution to our understanding of the neural networks impaired in Alzheimer's disease, but it has not yet provided a diagnostic marker. The limited benefit of tacrine as an approved form of treatment is still being defined, but no new therapies have emerged.

Aged↗
PubMed1994

Risk of dementia after stroke in a hospitalized cohort: results of a longitudinal study.

Stroke is considered the second most common cause of dementia, but the magnitude of the risk posed by stroke has not been fully clarified. The aim of this study was to determine the long-term risk of developing dementia after stroke onset in a hospitalized cohort. We prospectively examined 185 nondemented patients aged > or = 60 years hospitalized with ischemic stroke and 241 age-matched nondemented controls without stroke from the same community using neurologic, neuropsychological, and functional assessments given annually. Using criteria modified from the DSM-III-R, we diagnosed incident dementia based on the annual examination findings. We used life-table methods to estimate incidence in the two groups, Kaplan-Meier analysis to determine the proportion surviving without dementia, and Cox proportional-hazards analysis to compute the relative risk (RR) of dementia after 1 to 4 years of follow-up. The incidence of dementia was 8.4 per 100 person-years in the stroke group and 1.3 per 100 person-years in the control group. After 52 months of follow-up, the cumulative proportion (+/- SE) surviving without dementia was 66.3 +/- 5.5% for stroke and 90.3 +/- 4.3% for control subjects. The RR of dementia associated with stroke compared with controls was 5.5 (95% CI, 2.5 to 11.1) after adjusting for demographic factors. Older age at stroke onset and fewer years of education were significant covariates, but sex and race were not. A low score on the Mini-Mental State Examination at baseline was a significant predictor when added to this model.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1994

The apolipoprotein epsilon 4 allele in Parkinson's disease with and without dementia.

The epsilon 4 isoform of apolipoprotein E (Apo-E) may confer genetic susceptibility for familial and sporadic Alzheimer's disease (AD). Because dementia in AD and Parkinson's disease (PD) share many biologic and clinical features, we determined the Apo-E genotypes for 79 patients with PD, 22 of whom were demented, and for 44 age-matched healthy elderly controls from the same community. We hypothesized that if the dementia was similar to AD, there would be a higher allele frequency of apolipoprotein epsilon 4 (Apo epsilon 4) in demented PD patients compared with nondemented PD patients and controls. The epsilon 4 allele frequency for PD without dementia was 0.132, for PD with dementia, 0.068, and for controls, 0.102. There was no association between Apo epsilon 4 and dementia in the PD patients. We conclude that the biologic basis for dementia in PD may differ from that of AD.

Aged↗
PubMed1993

Comparison of cognitive changes in patients with Alzheimer's and Parkinson's disease.

OBJECTIVE: To compare cognitive changes in the dementias of Parkinson's disease (PD) and Alzheimer's disease (AD). DESIGN: Case series, group comparisons. SETTING: Ambulatory care referral center. PATIENTS: Consecutive sample of 14 patients with PD dementia and 27 with probable AD matched for overall intellectual function using a mental status test, as well as 14 non-demented PD and 12 mild probable AD patients, similarly matched for overall intellectual function. All demented patients met Diagnostic and Statistical Manual, Revised Third Edition, criteria for dementia. MAIN OUTCOME MEASURES: Performance on a battery of neuropsychological tests assessing verbal and nonverbal memory, verbal fluency, and constructional ability. RESULTS: Nondemented and demented patients with PD performed worse than their probable AD comparison groups on verbal fluency and visuospatial tasks. Cognitive changes attributable to dementia were similar in PD and probable AD but were not identical. The patients with probable AD demonstrated more marked change in memory performance with delay. CONCLUSIONS: Our findings suggest that when dementia occurs in PD it is overlaid on cognitive changes that already exist in nondemented patients but that the dementing process in PD involves systems other than those responsible for cognitive change in nondemented PD patients. We hypothesize that in most cases, dementia in PD involves changes in a nondopaminergic neurotransmitter system but is not due to concomitant AD.

Alzheimer Disease↗
PubMed1993

Relationships between extrapyramidal signs and cognitive function in a community-dwelling cohort of patients with Parkinson's disease and normal elderly individuals.

The relationship between extrapyramidal sign (EPS) severity and cognitive function was investigated in 184 patients with idiopathic Parkinson's disease (PD) and 301 normal elderly individuals from a community-dwelling cohort in northern Manhattan, New York City. Fifty-six of the patients with PD met criteria for dementia of the Diagnostic and Statistical Manual of Mental Disorders, third edition, revised, and of the National Institute of Neurological and Communicative Disorders and Stroke-Alzheimer's Disease and Related Disorders Association. EPS were rated according to the Unified Parkinson's Disease Rating Scale. Cognitive function was assessed by neuropsychological tests of memory, orientation, abstract reasoning, language, construction, and psychomotor speed. Significant associations were found between EPS and neuropsychological performance in PD patients without dementia. Yet EPS severity was unable to account for the pronounced cognitive impairment in PD dementia. Individuals in the normal group with subtle EPS, but without overt idiopathic PD, showed widespread cognitive changes, including impairment in most of the tests that differentiated PD patients from normal subjects. Prospective follow-up of these individuals will determine whether this represents a preclinical stage of PD or constitutes an early manifestation of dementia.

Aged↗
PubMed1993

Genetic susceptibility and head injury as risk factors for Alzheimer's disease among community-dwelling elderly persons and their first-degree relatives.

We performed a community-based study to investigate the relationship of genetic susceptibility and head injury to Alzheimer's disease (AD) in 138 patients with AD and 193 healthy elderly control subjects. Data concerning presence or absence of dementia and certain exposures were also obtained from 799 first-degree relatives of the patients and 1,238 first-degree relatives of the control subjects. Adjusting for age, gender, and other risk factors, the odds ratio for AD associated with head injury was 3.7 (95% confidence interval [CI], 1.4-9.7). The association was highest for head injuries that occurred after age 70. The risk of AD was higher in first-degree relatives of patients with onset prior to age 70 than in relatives of control subjects (risk ratio [RR] = 2.5; 95% CI, 1.1-5.6). The risk was not increased for relatives of patients with onset of AD at age 70 or older. Compared with relatives without head injury, the risk of AD was increased among both head-injured relatives of patients (RR = 5.9; 95% CI, 2.3-14.8) and head-injured relatives of control subjects (RR = 6.9; 95% CI, 2.5-18.9). Our results are consistent with the hypothesis that severe head injury and genetic susceptibility are associated with AD. Both associations concur with current concepts regarding the role of amyloid in AD. Although we regard head injury, like genetic susceptibility, to be a putative risk factor for AD, the temporal relationship between head injury and AD warrants further investigation.

Age Factors↗
PubMed1993

The apolipoprotein epsilon 4 allele in patients with Alzheimer's disease.

Apolipoprotein E (APO-E) binds to the beta-amyloid peptide and is present in senile neuritic plaques in Alzheimer's disease (AD). The epsilon 4 isoform of APO-E has been associated with both sporadic and familial late-onset AD, implying a causal role. Among patients and control subjects similar in age, gender, and ethnic group from the New York City community of Washington Heights-Inwood, we found that the odds ratio (OR) for AD associated with homozygosity for APO-epsilon 4 was 17.9 (95% confidence interval [CI], 4.6-69.8) and that associated with heterozygosity for APO-epsilon 4 was 4.2 (95% CI, 1.8-9.5) compared with persons with other APO-E genotypes. The association was stronger among patients with sporadic disease (OR = 10.3; 95% CI, 3.4-31.1) than among those with a family history of dementia in a first-degree relative (OR = 0.9; 95% CI, 0.1-13.5). The association between APO-epsilon 4 and AD did not differ according to age at onset (< 65 vs > or = 65), but appeared to vary across the 3 ethnic groups investigated (black, Hispanic, and white). Our data confirm the association between AD and APO-epsilon 4 and support the hypothesis that the APO-epsilon 4 allele either confers genetic susceptibility to AD or may be in linkage disequilibrium with another susceptibility locus. Ethnic variability in the allelic frequency of APO-epsilon 4 in the elderly warrants further investigation.

Aged↗