Biomedical subjects

N L Foster

Publications and source records attributed to N L Foster.

77 records · Page 5Linked to original sources

PubMedDate not supplied

Caregivers' attitudes toward their family members' participation in Alzheimer disease research: implications for recruitment and retention.

Current levels of participation in Alzheimer disease (AD) research are inadequate, particularly among nonwhites. This study was conducted to examine caregivers' attitudes toward their family members' participation in AD research. Six focus group interviews were conducted with 38 white and 12 African-American caregivers of participants enrolled in clinical research projects. Both white and African-American families participated in research to help their care recipients and future generations, receive support from the clinical and research staff, and obtain feedback about patient status and research results. Among white caregivers, primary barriers to participation in research included the potential for no direct benefit, problems with the procedures and tests involved, lack of time and resources, and difficulty accepting the diagnosis. Among African-American caregivers, primary barriers included general skepticism about the research process and firmly established attitudes about medical treatment and help seeking that serve as disincentives to research participation. To maximize the perceived benefits of research participation, potential participants should have access to regular personal contact with staff, information about health status changes in the care recipient, and the short-term and long-term results of the research studies in which they are participants. In addition, researchers should be sensitive to the concerns that may serve as barriers to participation, particularly among African Americans.

Adult↗

PubMedDate not supplied

Preserved pontine glucose metabolism in Alzheimer disease: a reference region for functional brain image (PET) analysis.

OBJECTIVE: Our goal was to examine regional preservation of energy metabolism in Alzheimer disease (AD) and to evaluate effects of PET data normalization to reference regions. MATERIALS AND METHODS: Regional metabolic rates in the pons, thalamus, putamen, sensorimotor cortex, visual cortex, and cerebellum (reference regions) were determined stereotaxically and examined in 37 patients with probable AD and 22 normal controls based on quantitative 18FDG-PET measurements. Following normalization of metabolic rates of the parietotemporal association cortex and whole brain to each reference region, distinctions of the two groups were assessed. RESULTS: The pons showed the best preservation of glucose metabolism in AD. Other reference regions showed relatively preserved metabolism compared with the parietotemporal association cortex and whole brain, but had significant metabolic reduction. Data normalization to the pons not only enhanced statistical significance of metabolic reduction in the parietotemporal association cortex, but also preserved the presence of global cerebral metabolic reduction indicated in analysis of the quantitative data. CONCLUSION: Energy metabolism in the pons in probable AD is well preserved. The pons is a reliable reference for data normalization and will enhance diagnostic accuracy and efficiency of quantitative and nonquantitative functional brain imaging.

Aged↗

PubMedDate not supplied

Chronic donepezil treatment is associated with slowed cognitive decline in Alzheimer's disease.

OBJECTIVE: To compare rates of cognitive decline between probable Alzheimer's disease (AD) patients treated with long-duration cholinesterase inhibitors (ChE-Is) and those who remained untreated. BACKGROUND: ChE-Is, including donepezil and tracrine, have shown beneficial effects on cognition and global functioning in patients with AD. The duration of these benefits is unknown because the longest double-blind placebo-controlled studies reported were only approximately 6 months long. Ethical concerns regarding randomization of patients to placebo for long periods make it difficult to undertake trials of longer duration. METHODS: We identified patients in 4 AD centers who were or were not consistently treated with ChE-Is and who had demographic, psychometric and follow-up data. We compared 205 ChE-I-treated and 218 untreated AD patients on baseline variables hypothesized to differ between these groups, on baseline Mini Mental Status Examination (MMSE) scores and on rates of MMSE change at 1 year. The analysis was performed initially with all ChE-I-treated patients as a single group versus untreated subjects, and then with donepezil versus untreated subjects and tacrine versus untreated subjects. RESULTS: As expected, treated and untreated patients differed with respect to age, education, ethnicity, percentage of community dwelling and exact days of follow-up (ANOVA and chi2) in several comparisons, but did not differ on baseline MMSE score. These baseline variables were highly intercorrelated. MMSE scores declined significantly more slowly after 1 year of ChE-I treatment compared to untreated patients (p = 0.05) after controlling for baseline differences in age, education, ethnicity and percentage of community dwelling. Slowing of decline was significant in the donepezil-treated patients (p = 0.007) but not in the tacrine-treated group (p = 0.33). CONCLUSIONS: This study, utilizing concurrent, nonrandomized controls, suggests that donepezil continues to have efficacy over at least the first year of therapy. Other studies are needed to determine whether the benefits are maintained beyond 1 year.

Aged↗

PubMedDate not supplied

Apolipoprotein E and Alzheimer's disease: strength of association is related to age at onset.

Apolipoprotein E (apoE) epsilon 4 allele frequency among Alzheimer's disease (AD) patients is increased compared to control subjects and is influenced by the presence of other genetic factors and age at symptom onset. We examined the relationship between age at AD symptom onset and apoE by comparing the apoE epsilon 4 allele frequency of normal, elderly control subjects (n = 107) to that in AD patients (n = 123), divided into four age-at-onset periods. Additionally, the distribution of symptom onset ages of AD patients with and without apoE epsilon 4 alleles was determined. We observed increased apoE epsilon 4 allele frequencies between the AD onset ages of 55 and 75 years, but not at the extremes of onset ages (i.e. onset between 45 and 54 years of age and after age 75). Our data suggests that having an apoE epsilon 4 allele increases the likelihood that AD patients will develop symptoms in the middle range of onset ages. At the extremes of AD onset ages, non-apoE factors, including other genetic factors and age, are more important determinants of risk of developing AD.

Age of Onset↗

PubMedDate not supplied

An enriched-population, double-blind, placebo-controlled, crossover study of tacrine and lecithin in Alzheimer's disease. The Tacrine 970-6 Study Group.

We studied the effects of 40 and 80 mg/day of tacrine on patients with probable Alzheimer's disease (AD) in an 8-week, randomized, double-blind, placebo-controlled crossover trial with an enriched-population design. In the initial dose titration phase, an intent-to-treat analysis showed significantly more improvement with 80 mg/day of tacrine than placebo. In the subsequent crossover trial that included only 'responders', no significant improvement was observed with tacrine, whether or not it was given with lecithin. We found that individualized dose titration and enrichment strategies were not helpful and had the effect of reducing the power of the study. In the dose titration phase of this study we found that more impaired subjects were as likely to improve as those who were less impaired, suggesting that tacrine should be further investigated in more severely demented AD patients.

Aged↗