Biomedical subjects

Neelum T Aggarwal

Publications and source records attributed to Neelum T Aggarwal.

11 recordsLinked to original sources

PubMed2007

Vascular dementia: emerging trends.

Vascular dementia is a term used to describe a constellation of cognitive and functional impairment that can be viewed as a subset of the larger syndrome of vascular cognitive impairment associated with cerebrovascular brain injury. Vascular dementia is a common disorder among the elderly, although it can also occur in younger persons. Comprising 20% of all cases of dementia in the United States, vascular dementia is the second most common form of dementia after Alzheimer's disease. Patients with vascular dementia often exhibit mood and behavioral changes and may have focal neurological signs on neurological examination. Primary treatment is through primary or secondary modification of cerebrovascular risk factors such as hypertension, although symptomatic treatments with cholinesterase inhibitors have shown modest symptomatic benefit.

Brain↗

PubMed2006

Decision rules guiding the clinical diagnosis of Alzheimer's disease in two community-based cohort studies compared to standard practice in a clinic-based cohort study.

We developed prediction rules to guide the clinical diagnosis of Alzheimer's disease (AD) in two community-based cohort studies (the Religious Orders Study and the Rush Memory and Aging Project). The rules were implemented without informant interviews, neuroimaging, blood work or routine case conferencing. Autopsies were performed at death and the pathologic diagnosis of AD made with a modified version of the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) criteria. We compared the positive predictive value of the clinical diagnosis in the two community-based studies to the positive predictive value of the clinical diagnosis of AD made by standard clinical practice in a clinic-based cohort study using AD pathology as the gold standard. Of 306 clinic cases with probable AD, 286 (93.5%) met CERAD neuropathologic criteria for AD; the results were comparable for those with possible AD (51 of 54, 94.4%). Of 141 study subjects with probable AD, 130 (92.2%) met CERAD neuropathologic criteria for AD; the results were lower but acceptable for those with possible AD (26 of 37, 70.3%). The results were similar in secondary analyses using alternate neuropathologic criteria for AD. The clinical diagnosis of AD can be made in community-based studies without the use of informant interviews, neuroimaging, blood work or routine case conferencing. This approach holds promise for reducing the operational costs of epidemiologic studies of aging and AD.

Aged↗

PubMed2006

The relation of cigarette smoking to incident Alzheimer's disease in a biracial urban community population.

The relationship between smoking status and incident Alzheimer's disease (AD) was investigated in a random stratified sample of a biracial community in Chicago. Analyses are based on 1,064 persons (of 1,134 evaluated) who had data on smoking status, disease incidence, and key covariates such as apolipoprotein allele status. During a mean of about 4 years of follow-up, 170 persons met criteria for incident AD. Current smoking was associated with increased risk of incident AD (OR = 3.4, 95% CI = 1.4-8.0) compared to persons who never smoked. There was no apparent increase in risk of AD for former smokers compared to persons who never smoked (OR = 0.9, 95% CI = 0.5-1.7). Apolipoprotein E allele status modified this association in that former smokers with a upsilon4 allele were less likely to develop AD (p = 0.04) than those who never smoked. Former smokers also appeared to have a reduced risk of developing AD as their pack-years of smoking increased (p = 0.02)such that the odds of developing AD increased by 50% for every 10 years of smoking cessation (OR = 1.3, CI = 0.9-1.7). The results suggest that older people who currently smoke are more likely to develop AD compared to those who never smoked; the relation between those who used to smoke but quit and the risk of AD is complex and requires further research.

Black or African American↗

PubMed2006

Motor dysfunction in mild cognitive impairment and the risk of incident Alzheimer disease.

BACKGROUND: Little is known about motor function in mild cognitive impairment (MCI) and its relation to the risk of Alzheimer disease (AD). OBJECTIVE: To examine motor function in persons with MCI and its relation to risk of AD. DESIGN: Longitudinal cohort study. SETTING: More than 40 Catholic religious orders across the United States. PARTICIPANTS: We studied 816 older Catholic clergy members from the Religious Orders Study. At the baseline evaluation, they were classified as having no cognitive impairment (n = 558), MCI (n = 198), or dementia (n = 60). MAIN OUTCOME MEASURES: Motor function was assessed at baseline using performance-based measures of upper and lower extremity function and a modified version of the motor section of the Unified Parkinson's Disease Rating Scale, from which previously established measures of parkinsonian signs were derived. Clinical evaluations for dementia and AD were repeated annually for up to 10 years. All analyses controlled for age, sex, educational level, and possession of at least 1 apolipoprotein E epsilon4 allele. RESULTS: At baseline, individuals with MCI had impaired motor function relative to those without cognitive impairment and superior motor function vs those with dementia. Among those with MCI, baseline levels of lower extremity motor performance, parkinsonian gait, and bradykinesia were inversely related to risk of AD, even after controlling for clinical stroke. Thus, a person with impaired lower limb performance or parkinsonian gait (10th percentile) was 2 to 3 times more likely to develop AD than a person with good lower limb function (90th percentile). CONCLUSIONS: Persons with MCI also have impaired motor function, and the degree of impairment in lower extremity function is related to the risk of AD.

Age Factors↗

PubMed2006

Cognitive decline and survival in Alzheimer's disease.

OBJECTIVE: To test the association of rate of cognitive decline, an indicator of the severity of the underlying disease process, with risk of death in Alzheimer's disease (AD). METHODS: A total of 472 persons with clinically diagnosed AD were recruited from a memory disorders clinic and day care centers in the Chicago area. They completed a uniform clinical evaluation at baseline and a battery of nine cognitive tests at six-month intervals for a mean of about three years. A previously established measure of global cognition was derived from the nine tests. RESULTS: During follow-up, 168 persons (36%) died. In a proportional hazards model that controlled for age, sex, race, education, and baseline level of cognition, individual rate of global cognitive decline, estimated with least squares regression, was linearly related to mortality risk. Thus, a person declining minimally (increase of 0.04 unit per year, 90th percentile) was 2.7 times less likely to die during the study period than a person declining rapidly (decrease of 0.76 unit per year, 10th percentile). Controlling for baseline disability did not substantially affect results. The association of cognitive decline with mortality was substantially stronger for white persons compared to African Americans and in those with less compared to more education. CONCLUSION: The results indicate that the rate at which cognition declines in AD is robustly related to survival.

Adult↗

PubMed2006

Dietary folate and vitamins B-12 and B-6 not associated with incident Alzheimer's disease.

CONTEXT: It is currently not known whether dietary intakes of folate and vitamins B12 and B6, co-factors in the methylation of homocysteine, protect against Alzheimer's disease. OBJECTIVE: To examine the association between risk of incident Alzheimer's disease and dietary intakes of folate, vitamin B-12, and vitamin B-6. DESIGN: Prospective cohort study. SETTING: Geographically defined biracial Chicago community. PARTICIPANTS: 1,041 residents, aged 65 years and older, initially free of Alzheimer's disease and followed a median 3.9 years for the development of incident disease. MAIN OUTCOME MEASURE: Probable Alzheimer's disease identified through structured clinical neurological evaluation using standardized criteria. RESULTS: A total of 162 persons developed incident Alzheimer's disease during follow-up. In logistic regression models adjusted for age, sex, race, education, cognitive activities, APOE-epsilon4, and dietary intakes of vitamin E in food and total niacin, there was no association between risk of developing Alzheimer's disease and quintiles of folate intake or of vitamin B-12 intake. The adjusted odds ratio was 1.6 (95% confidence interval: 0.5, 5.2) for persons in the highest quintile of total folate intake (median of 752.7 microg/d) compared with persons in the lowest quintile of intake (median, 202.8 microg/d). Compared with persons in the first quintile of total vitamin B-12 intake (median, 3.1 microg/d) the odds ratio was 0.6 (95% confidence interval: 0.2, 1.6) for persons in the fifth quintile of intake (median, 20.6 microg/d). Intake of vitamin B-6 was not associated with incident Alzheimer's disease after control for dietary intakes of vitamin E and total niacin. CONCLUSION: Dietary intakes of folate, vitamin B-12, or vitamin B-6 do not appear to be associated with the development of Alzheimer's disease.

Aged↗

PubMed2005

The apolipoprotein E epsilon4 allele and incident Alzheimer's disease in persons with mild cognitive impairment.

Possession of one or more copies of the apolipoprotein E (APOE) epsilon4 allele is a known risk factor for Alzheimer's disease (AD), but it is uncertain whether the epsilon4 allele is associated with disease incidence among persons with mild cognitive impairment (MCI). We addressed this issue with data from the Religious Orders Study. Participants were 181 older Catholic clergy members who met criteria for MCI based on a uniform structured clinical evaluation; 56 (30.9%) had at least one epsilon4 allele. Clinical evaluations, which included clinical classification of dementia and AD, were repeated annually. During a mean of 5.7 years of observation, 79 persons (43.6%) developed AD. In a proportional hazards model that controlled for age, sex, and education, possession of an epsilon4 allele was associated with a 93% increase in the risk of developing Alzheimer's disease (95% CI; 1.02, 2.63). There was a marginally significant reduction in the effect of epsilon4 in older compared to younger participants (p=.053). The results suggest that possession of an epsilon4 allele does increase risk of AD in persons with MCI.

Aged↗

PubMed2005

Relation of the tocopherol forms to incident Alzheimer disease and to cognitive change.

BACKGROUND: High intake of vitamin E from food (tocopherol), but not from supplements (which usually contain alpha-tocopherol), is inversely associated with Alzheimer disease. OBJECTIVE: We examined whether food intakes of vitamin E, alpha-tocopherol equivalents (a measure of the relative biologic activity of tocopherols and tocotrienols), or individual tocopherols would protect against incident Alzheimer disease and cognitive decline over 6 y in participants of the Chicago Health and Aging Project. DESIGN: The 1993-2002 study of community residents aged >or=65 y included the administration of 4 cognitive tests and clinical evaluations for Alzheimer disease. Dietary assessment was by food-frequency questionnaire. RESULTS: Tocopherol intake from food was related to the 4-y incidence of Alzheimer disease determined by logistic regression in 1041 participants who were clinically evaluated (n=162 incident cases) and to change in a global cognitive score determined by mixed models in 3718 participants. Higher intakes of vitamin E (relative risk: 0.74 per 5 mg/d increase; 95% CI: 0.62, 0.88) and alpha-tocopherol equivalents (relative risk: 0.56 per 5 mg/d increase; 95% CI: 0.32, 0.98) were associated with a reduced incidence of Alzheimer disease in separate multiple-adjusted models that included intakes of saturated and trans fats and docosahexaenoic acid. alpha- and gamma-Tocopherol had independent associations. In separate mixed models, a slower rate of cognitive decline was associated with intakes of vitamin E, alpha-tocopherol equivalents, and alpha- and gamma-tocopherols. CONCLUSION: The results suggest that various tocopherol forms rather than alpha- tocopherol alone may be important in the vitamin E protective association with Alzheimer disease.

Aged↗

PubMed2005

The effect of adult day care services on time to nursing home placement in older adults with Alzheimer's disease.

PURPOSE: This longitudinal study examined whether the use of adult day care services delayed time to nursing home placement in persons with Alzheimer's disease. DESIGN AND METHODS: Two hundred and eighteen adult day care clients with Alzheimer's disease were recruited from 16 adult day programs in a large metropolitan area. Two hundred and ninety eight persons with Alzheimer's disease but not using adult day care were recruited from a federally funded Alzheimer's diagnostic center and frequency matched to adult day care users on age, gender, race, and level of cognitive impairment. Participants were followed at 3-month intervals for up to 48 months. Cox proportional hazards models were used to examine the effects of adult day care and other fixed and time-varying factors on risk of nursing home placement. RESULTS: Risk of nursing home placement increased significantly with the number of days of adult day care attendance, with this effect being substantially greater for men (hazard ratio or HR = 1.33; confidence interval or CI = 1.18-1.49) than for women (HR = 1.09; CI = 1.00-1.18). Participant disability and hospitalizations and caregiver age and burden were independent predictors, but their inclusion in the model did not alter the risk associated with adult day care. IMPLICATIONS: More severe disease and greater caregiver burden did not explain the increased risk of nursing home placement among adult day care users with Alzheimer's disease. Rather, it appears that other unmeasured factors, such as a proclivity to institutionalize, may account for the association of adult day care to nursing home risk.

Alzheimer Disease↗

PubMed2005

Racial differences in the progression of cognitive decline in Alzheimer disease.

OBJECTIVE: Alzheimer disease (AD) is the leading cause of dementia in older persons, but little is known about racial differences in its clinical manifestations. The purpose of the current study was to examine the association of race with rate of cognitive decline in AD. METHODS: Older persons with clinically diagnosed AD were recruited from healthcare settings. At 6-month intervals for up to 4 years, they completed a battery of nine cognitive tests from which a previously established measure of global cognition was derived. Follow-up data were available on 452 participants (27.6% African American, 68.8% women), 88.1% of those eligible. RESULTS: A growth curve approach was used to estimate individual paths of change in global cognition. In a model that controlled for age and education, African Americans had a lower level of global cognition at baseline than non-African Americans, but declined at a 25% slower rate on average. In additional models, there was no indication that the association of race with cognitive decline varied by age, gender, or education. CONCLUSION: The rate of cognitive decline in AD appears to be slower in African Americans than non-African Americans.

Adult↗

PubMed2002

The apolipoprotein E epsilon 4 allele and decline in different cognitive systems during a 6-year period.

CONTEXT: Impairment of episodic memory is an early and defining feature of Alzheimer disease (AD). The apolipoprotein E (APOE) epsilon 4 allele is known to influence risk of AD but it has been difficult to establish whether it affects episodic memory differently from other cognitive functions. OBJECTIVE: To examine the association of epsilon 4 with decline in different cognitive systems. DESIGN: Longitudinal cohort study. SETTING: More than 40 groups of Catholic clergy from across the United States. PARTICIPANTS: Older Catholic clergy members without clinical evidence of dementia at baseline underwent annual clinical evaluations for up to 6 years. Of 624 persons eligible for follow-up, 611 (98%) participated, of whom 161 (26%) had at least 1 epsilon 4 allele. They completed an average of 5.5 evaluations (range, 2-7). MAIN OUTCOME MEASURES: Incident AD and annual rates of change in episodic memory, semantic memory, working memory, perceptual speed, and visuospatial ability. RESULTS: The presence of epsilon 4 was associated with risk of developing AD on follow-up (relative risk, 1.92; 95% confidence interval, 1.27-2.89). In a series of random effects models, epsilon 4 was associated with impaired baseline function in episodic memory and visuospatial ability and with more rapid decline in all domains. The effect of epsilon 4 on annual decline in episodic memory (>3-fold increase) was significantly stronger than its effect on decline in other cognitive systems (P<.01), and at baseline, its effect on episodic memory was marginally stronger than its effect on other cognitive domains (P =.06). CONCLUSION: The results suggest that the APOE epsilon 4 allele influences risk of AD by a relatively selective effect on episodic memory.

Aged↗