Journal of Alzheimer's disease : JAD
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Multicenter Study Clinical Trial
Sustained effects of once-daily memantine treatment on cognition and functional communication skills in patients with moderate to severe Alzheimer's disease: results of a 16-week open-label trial.
The present study evaluated the effects of once-daily memantine (20 mg) treatment on cognition and communication in patients with moderate to severe Alzheimer's disease (AD). In a multicenter, single-arm open-label study, outpatients diagnosed with AD (MMSE < 20; n = 97) were titrated from 5 mg to 20 mg once-daily memantine over 4 weeks. Once-daily memantine treatment (20 mg) was then continued for 8 weeks, followed by a 4-week wash-out period. ⋯ ADCS-ADL19 total scores showed only slight increases from baseline, and CGI-C indicated that the majority of patients experienced an improvement or stabilization of the disease after 12 weeks. At least one Treatment-Emergent Adverse Event was reported by 38 (39.2%) patients. In patients with moderate to severe AD, once-daily memantine (20 mg) treatment significantly improved cognition and functional communication and was found to have a favorable safety and tolerability profile.
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Manual segmentation from magnetic resonance imaging (MR) is the gold standard for evaluating hippocampal atrophy in Alzheimer's disease (AD). Nonetheless, different segmentation protocols provide up to 2.5-fold volume differences. Here we surveyed the most frequently used segmentation protocols in the AD literature as a preliminary step for international harmonization. ⋯ Semantically harmonized landmarks and differences were then extracted, regarding: (a) the posteriormost slice, protocol [B] being the most restrictive, and [H, M, Pa, Pr, S] the most inclusive; (b) inclusion [C, dTM, J, L, M, Pr, W] or exclusion [B, H, K, Pa, S] of alveus/fimbria; (c) separation from the parahippocampal gyrus, [C] being the most restrictive, [B, dTM, H, J, Pa, S] the most inclusive. There were no substantial differences in the definition of the anteriormost slice. This survey will allow us to operationalize differences among protocols into tracing units, measure their impact on the repeatability and diagnostic accuracy of manual hippocampal segmentation, and finally develop a harmonized protocol.
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Distinguishing amnestic mild cognitive impairment (MCI) from Alzheimer's disease (AD) and healthy aging depends mainly on clinical evaluation, and, ultimately, on investigator's judgment. Clinical evaluation in vivo is based primarily on cognitive assessments. The present study explores the potential of volumetric magnetic resonance imaging of parietal and lateral temporal brain structures to support the diagnosis of AD and to distinguish AD patients from patients with MCI and healthy control subjects (HCS). 52 age-matched HCS, 18 patients with MCI, and 59 patients with probable late onset AD were investigated. ⋯ The left superior temporal pole (92.3%/84.7%), left parahippocampal gyrus (86.5%/81.4%), left Heschl's gyrus (86.5%/79.7%), and the right superior temporal pole (82.7%/78.0%) revealed most promising diagnostic values for distinguishing AD patients from HCS. Data revealed that lateral temporal and parietal GM volumes distinguish between HCS, MCI, and AD as accurate as hippocampal volumes do; hence, these volumes can be used in the diagnostic procedure. Results also suggest that cognitive functions associated with these brain regions, e.g., language and visuospatial abilities, may be tested more extensively to obtain additional information that might enhance the diagnostic accuracy further.
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A strong perception exists that elderly people are at risk for persistent cognitive deterioration lasting longer than six months following major surgery, particularly heart surgery. Furthermore, based on laboratory evidence, investigators hypothesize that surgery or anesthesia might precipitate incident dementia. Recent clinical studies have found that cognition might frequently be impaired within the first few months postoperatively, and that such impairment may be associated with death or debility. ⋯ There is evidence that most patients recover cognition in the long-term, and that for those who experience persistent decline, this is probably attributable to underlying undiagnosed neurological disease or other co-morbidities rather than to surgery or to anesthesia. There is currently minimal clinical evidence linking surgery or anesthesia to incident dementia. Rigorous clinical research is needed to resolve the controversy whether anesthesia or surgery is likely to cause persistent neurological decline or to precipitate dementia.
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Comparative Study
Episodic memory decline predicts cortical amyloid status in community-dwelling older adults.
Intra-individual decline in memory and cognition is characteristic of prodromal Alzheimer's disease (AD) and may allow detection of very early AD pathology. Episodic memory task scores on a brief computerized cognitive battery (CogState) were prospectively evaluated at baseline, and 3-, 6-, 9-, 12-, and 24-months post-baseline. Linear mixed models were conducted to compute age-adjusted slopes. ⋯ One of the memory decliners and none of the non-decliners fulfilled criteria for mild cognitive impairment, but the groups did not differ with respect to subjective memory impairment, neuropsychological evidence of episodic memory impairment, or MRI imaging abnormalities. Intra-individual decline in episodic memory can be detected using a brief computerized cognitive performance test optimized to detect change in community-dwelling non-demented older persons and appears predictive of the presence of cerebral amyloid in about half of these persons. This approach may help detect early prodromal AD pathology in wider-scale community screening programs.