Meta-analysis of double blind randomized controlled clinical trials of acetyl-L-carnitine versus placebo in the treatment of mild cognitive impairment and mild Alzheimer??s disease
Abstract
The efficacy of acetyl-L-carnitine (gamma-trimethyl- beta-acetylbutyrobetaine (Alcar) in mild cognitive impairment (MCI) and mild (early) Alzheimer's disease (AD) was investigated with a meta-analysis of double-blind, placebo-controlled prospective, parallel group comparison studies of at least 3 months duration. The duration of the studies was 3, 6 or 12 months and the daily dose varied between studies from 1.5-3.0 g/day. An effect size was calculated to reflect the results of the variety of measures used in the studies grouped into the categories of clinical tests and psychometric tests. The effect sizes from the categories were integrated into an overall summary effect size. The effect size for the Clinical Global Impression of Change (CGI-CH) was calculated separately. Meta-analysis showed a significant advantage for Alcar compared to placebo for the integrated summary effect [ES =0.201, 95% confidence interval (CI)=0.107-0.295] and CGI-CH (ES =0.32, 95% CI=0.18-0.47). The beneficial effects were seen on both the clinical scales and the psychometric tests. The advantage for Alcar was seen by the time of the first assessment at 3 months and increased over time. Alcar was well tolerated in all studies.
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Acetyl-L-carnitine's beneficial effects on cognition have been documented in the treatment of mild cognitive impairment and Alzheimer's disease, as well as of hepatic encephalopathy.
“ALC’s beneficial effects on cognition have been documented in the treatment of mild cognitive impairment and Alzheimer’s disease, as well as of hepatic encephalopathy [129, 130].”
From Cognitive remission: a novel objective for the treatment of major depression? (2016) · cites this paper as [130]
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- Authors
- Montgomery, S. A., Thal, L. J., & Amrein, R.
- Affiliations
- University of London (GB)
- University of California San Diego (US)
- Corresponding author
- Montgomery, Stuart A.
- Venue
- International Clinical Psychopharmacology
- Published
- 2003-03
- Volume
- 18
- Issue
- 2
- Pages
- 61-71
- ISSN
- 0268-1315 (ISSN-L)
- OpenAlex
- W12598816
- Cited by
- 209
- References
- 28
- Citations by year
- 2026: 3 · 2025: 4 · 2024: 7 · 2023: 7 · 2022: 9 · 2021: 12 · 2020: 8 · 2019: 9 · 2018: 4 · 2017: 12 · 2016: 9 · 2015: 9 · 2014: 9 · 2013: 9 · 2012: 12
- FWCI
- 1.63
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- International Clinical Psychopharmacology (publishedVersion)
- PubMed (publishedVersion)
- Tạp chí Thông tin và Tư liệu
- Topics
- Health Sciences › Medicine › Psychiatry and Mental health › Dementia and Cognitive Impairment Research
- Health Sciences › Medicine › Physiology › Alzheimer's disease research and treatments
- Life Sciences › Neuroscience › Neurology › Neurological Disorders and Treatments
- Keywords
- acetyl-L-carnitine, mild cognitive impairment, mild Alzheimer's disease, early Alzheimer's disease, cognitive function, Clinical Global Impression of Change, psychometric tests, drug efficacy, tolerability
- MeSH terms
- Acetylcarnitine, Aged, Alzheimer Disease, Cognition, Humans, Prospective Studies, Randomized Controlled Trials as Topic, Nootropic Agents
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