Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2001-2-14
pubmed:abstractText
A proportion of Alzheimer's disease (AD) patients treated for several months with cholinesterase (ChE) inhibitors have shown some favorable response on cognition, but the characteristics of the responders are still unclear. This study attempts to identify the characteristics of individuals with a positive behavioral response after a double-blind randomized administration of a single oral dose of tacrine (40 mg) and placebo to AD patients. Furthermore, the relationship between single-dose and long-term responders are examined. Twenty-four mildly to very mildly demented AD patients participated in the study. They all fulfilled the diagnosis of probable AD according to NINCDS-ADRDA criteria. Active treatment (tacrine 40 mg) and placebo was administered in random order on 2 consecutive days, and the effects were evaluated within 2 h using neuropsychological tests (assessing visuospatial ability, episodic memory and attention), registration of EEG activity and measurement of red blood cells (RBC) acetylcholinesterase (AChE), ChE activity and concentrations of tacrine and its metabolites in plasma. Results demonstrated significant improvement, tacrine compared to placebo, in measures of attention, but not in episodic memory or visuospatial ability. A single-dose response was therefore defined in terms of improvement in attention. The tacrine plasma concentration (pcTHA) showed a positively skewed distribution (mean +/- SD: 10.5 +/- 11.8, range: 1.0-51.8 ng/ml). There were no significant differences between single-dose responders compared to nonresponders in pcTHA, metabolites of tacrine, inhibition of AChE in RBC, tau levels in CSF, AChE activity in CSF or plasma and demographic variables. However, single-dose responders showed a higher right frontal alpha/theta ratio on EEG and had lower glucose metabolism in the parietal-temporal association cortex at baseline. In addition, the frequency of apolipoprotein E (APOE) epsilon 4 alleles was higher in responders. Interestingly, the single-dose response was related to the long-term response, although not significantly, which probably was due to lack of power. To conclude, the present study identified single-dose responders in terms of improved attentional performance associated with a relatively higher alpha/theta activity in the right frontal regions of the brain measured on EEG and predominance of APOE epsilon 4 allele.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
1420-8008
pubmed:author
pubmed:copyrightInfo
Copyright 2001 S. Karger AG, Basel
pubmed:issnType
Print
pubmed:volume
12
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
22-32
pubmed:dateRevised
2008-3-24
pubmed:meshHeading
pubmed-meshheading:11125238-Acetylcholine, pubmed-meshheading:11125238-Administration, Oral, pubmed-meshheading:11125238-Aged, pubmed-meshheading:11125238-Alleles, pubmed-meshheading:11125238-Alzheimer Disease, pubmed-meshheading:11125238-Apolipoprotein E4, pubmed-meshheading:11125238-Apolipoproteins E, pubmed-meshheading:11125238-Attention, pubmed-meshheading:11125238-Brain, pubmed-meshheading:11125238-Cholinesterase Inhibitors, pubmed-meshheading:11125238-Cognition, pubmed-meshheading:11125238-Cross-Over Studies, pubmed-meshheading:11125238-Double-Blind Method, pubmed-meshheading:11125238-Electroencephalography, pubmed-meshheading:11125238-Female, pubmed-meshheading:11125238-Humans, pubmed-meshheading:11125238-Male, pubmed-meshheading:11125238-Middle Aged, pubmed-meshheading:11125238-Neuropsychological Tests, pubmed-meshheading:11125238-Severity of Illness Index, pubmed-meshheading:11125238-Tacrine, pubmed-meshheading:11125238-Tomography, Emission-Computed
pubmed:articleTitle
Responder characteristics to a single oral dose of cholinesterase inhibitor: a double-blind placebo-controlled study with tacrine in Alzheimer patients.
pubmed:affiliation
Division of Geriatric Medicine, Department of Clinical Neuroscience, Occupational Therapy and Elderly Care Research (NEUROTEC), Huddinge University Hospital, Huddinge, Sweden.
pubmed:publicationType
Journal Article, Clinical Trial, Randomized Controlled Trial, Research Support, Non-U.S. Gov't