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British Journal of Sports Medicine Jun 2022Physical activity (PA) is associated with a decreased incidence of dementia, but much of the evidence comes from short follow-ups prone to reverse causation. This... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVE
Physical activity (PA) is associated with a decreased incidence of dementia, but much of the evidence comes from short follow-ups prone to reverse causation. This meta-analysis investigates the effect of study length on the association.
DESIGN
A systematic review and meta-analysis. Pooled effect sizes, dose-response analysis and funnel plots were used to synthesise the results.
DATA SOURCES
CINAHL (last search 19 October 2021), PsycInfo, Scopus, PubMed, Web of Science (21 October 2021) and SPORTDiscus (26 October 2021).
ELIGIBILITY CRITERIA
Studies of adults with a prospective follow-up of at least 1 year, a valid cognitive measure or cohort in mid-life at baseline and an estimate of the association between baseline PA and follow-up all-cause dementia, Alzheimer's disease or vascular dementia were included (n=58).
RESULTS
PA was associated with a decreased risk of all-cause dementia (pooled relative risk 0.80, 95% CI 0.77 to 0.84, n=257 983), Alzheimer's disease (0.86, 95% CI 0.80 to 0.93, n=128 261) and vascular dementia (0.79, 95% CI 0.66 to 0.95, n=33 870), even in longer follow-ups (≥20 years) for all-cause dementia and Alzheimer's disease. Neither baseline age, follow-up length nor study quality significantly moderated the associations. Dose-response meta-analyses revealed significant linear, spline and quadratic trends within estimates for all-cause dementia incidence, but only a significant spline trend for Alzheimer's disease. Funnel plots showed possible publication bias for all-cause dementia and Alzheimer's disease.
CONCLUSION
PA was associated with lower incidence of all-cause dementia and Alzheimer's disease, even in longer follow-ups, supporting PA as a modifiable protective lifestyle factor, even after reducing the effects of reverse causation.
Topics: Alzheimer Disease; Dementia, Vascular; Disease Progression; Exercise; Humans; Prospective Studies; Protective Factors
PubMed: 35301183
DOI: 10.1136/bjsports-2021-104981 -
Antipsychotics for agitation and psychosis in people with Alzheimer's disease and vascular dementia.The Cochrane Database of Systematic... Dec 2021Typical and atypical antipsychotics are widely used to treat agitation and psychosis in dementia. However, whether or not they are beneficial is uncertain. Some trials... (Review)
Review
BACKGROUND
Typical and atypical antipsychotics are widely used to treat agitation and psychosis in dementia. However, whether or not they are beneficial is uncertain. Some trials have yielded negative results and effectiveness may be outweighed by harms.
OBJECTIVES
To assess the efficacy and safety of antipsychotics for the treatment of agitation and psychosis in people with Alzheimer's disease and vascular dementia.
SEARCH METHODS
We searched ALOIS, the Cochrane Dementia and Cognitive Improvement Group's register, MEDLINE (Ovid Sp), Embase (Ovid SP), PsycINFO (Ovid SP), CINAHL (EBSCOhost), Web of Science Core Collection (ISI Web of Science), LILACS (BIREME), ClinicalTrials.gov and the World Health Organization's meta-register, and the International Clinical Trials Registry Portal on 7 January 2021. Two review authors independently screened the title and abstract of the hits, and two review authors assessed the full text of studies that got through this screening.
SELECTION CRITERIA
We included randomised, placebo-controlled, parallel-arm trials comparing the effects of antipsychotics and placebo for the treatment of agitation or psychosis in people with dementia due to Alzheimer's disease or vascular dementia, or both, irrespective of age, severity of cognitive impairment, and setting. (The majority of) participants had to have clinically significant agitation (including aggression) or psychosis or both at baseline. We excluded studies about antipsychotics that are no longer available in the USA or EU, or that are used for emergency short-term sedation. We also excluded head-to-head trials and antipsychotic withdrawal trials.
DATA COLLECTION AND ANALYSIS
The primary outcomes were (1) reduction in agitation or psychosis in participants with agitation or psychosis, respectively at baseline, and (2) the number of participants with adverse events: somnolence, extrapyramidal symptoms, any adverse event, any serious adverse event (SAE), and death. Two review authors independently extracted the necessary data and assessed risk of bias with the Cochrane risk of bias tool. We calculated the pooled effect on agitation and psychosis for typical and atypical antipsychotics separately, and the pooled risk of adverse effects independent of the target symptom (agitation or psychosis). We used RevMan Web for the analyses.
MAIN RESULTS
The search yielded 8233 separate hits. After assessing the full-text of 35 studies, we included 24 trials that met the eligibility criteria. Six trials tested a typical antipsychotic, four for agitation and two for psychosis. Twenty trials tested an atypical antipsychotic, eight for agitation and 12 for psychosis. Two trials tested both drug types. Seventeen of 26 comparisons were performed in patients with Alzheimer's disease specifically. The other nine comparisons also included patients with vascular dementia or mixed dementia. Together, the studies included 6090 participants (12 to 652 per study). The trials were performed in institutionalised, hospitalised and community-dwelling patients, or a combination of those. For typical antipsychotics (e.g. haloperidol, thiothixene), we are uncertain whether these drugs improve agitation compared with placebo (standardised mean difference (SMD) -0.36, 95% confidence interval (CI) -0.57 to -0.15, 4 studies, n = 361); very low-certainty evidence, but typical antipsychotics may improve psychosis slightly (SMD -0.29, 95% CI -0.55 to -0.03, 2studies, n= 240; low-certainty evidence) compared with placebo. These drugs probably increase the risk of somnolence (risk ratio (RR) 2.62, 95% CI 1.51 to 4.56, 3 studies, n = 466; moderate-certainty evidence) and increase extrapyramidal symptoms (RR 2.26, 95% CI 1.58 to 3.23, 3 studies, n = 467; high-certainty) evidence. There was no evidence regarding the risk of any adverse event. The risks of SAEs (RR 1.32, 95% CI 0.65 to 2.66, 1 study, n = 193) and death (RR 1.46, 95% CI 0.54 to 4.00, 6 studies, n = 578) may be increased slightly, but these estimates were very imprecise, and the certainty was low. The effect estimates for haloperidol from five trials were in line with those of the drug class. Atypical antipsychotics (e.g. risperidone, olanzapine, aripiprazole, quetiapine) probably reduce agitation slightly (SMD -0.21, 95% CI -0.30 to -0.12, 7 studies, n = 1971; moderate-certainty evidence), but probably have a negligible effect on psychosis (SMD -0.11, 95% CI -0.18 to -0.03, 12 studies, n = 3364; moderate-certainty evidence). These drugs increase the risk of somnolence (RR 1.93, 95% CI 1.57 to 2.39, 13 studies, n - 3878; high-certainty evidence) and are probably also associated with slightly increased risk of extrapyramidal symptoms (RR 1.39, 95% CI 1.14 to 1.68, 15 studies, n = 4180; moderate-certainty evidence), serious adverse events (RR 1.32, 95% CI 1.09 to 1.61, 15 studies, n= 4316; moderate-certainty evidence) and death (RR 1.36, 95% CI 0.90 to 2.05, 17 studies, n= 5032; moderate-certainty evidence), although the latter estimate was imprecise. The drugs probably have a negligible effect on the risk of any adverse event (RR 1.05, 95% CI 1.02 to 1.09, 11 studies, n = 2785; moderate-certainty evidence). The findings from seven trials for risperidone were in line with those for the drug class.
AUTHORS' CONCLUSIONS
There is some evidence that typical antipsychotics might decrease agitation and psychosis slightly in patients with dementia. Atypical antipsychotics reduce agitation in dementia slightly, but their effect on psychosis in dementia is negligible. The apparent effectiveness of the drugs seen in daily practice may be explained by a favourable natural course of the symptoms, as observed in the placebo groups. Both drug classes increase the risk of somnolence and other adverse events. If antipsychotics are considered for sedation in patients with severe and dangerous symptoms, this should be discussed openly with the patient and legal representative.
Topics: Alzheimer Disease; Antipsychotic Agents; Dementia, Vascular; Humans; Psychotic Disorders; Randomized Controlled Trials as Topic; Risperidone
PubMed: 34918337
DOI: 10.1002/14651858.CD013304.pub2 -
Alzheimer's Research & Therapy Jan 2019Alcohol use has been identified as a risk factor for dementia and cognitive decline. However, some patterns of drinking have been associated with beneficial effects.
BACKGROUND
Alcohol use has been identified as a risk factor for dementia and cognitive decline. However, some patterns of drinking have been associated with beneficial effects.
METHODS AND RESULTS
To clarify the relationship between alcohol use and dementia, we conducted a scoping review based on a systematic search of systematic reviews published from January 2000 to October 2017 by using Medline, Embase, and PsycINFO. Overall, 28 systematic reviews were identified: 20 on the associations between the level of alcohol use and the incidence of cognitive impairment/dementia, six on the associations between dimensions of alcohol use and specific brain functions, and two on induced dementias. Although causality could not be established, light to moderate alcohol use in middle to late adulthood was associated with a decreased risk of cognitive impairment and dementia. Heavy alcohol use was associated with changes in brain structures, cognitive impairments, and an increased risk of all types of dementia.
CONCLUSION
Reducing heavy alcohol use may be an effective dementia prevention strategy.
Topics: Alcohol Drinking; Brain; Cognitive Dysfunction; Dementia; Humans; Meta-Analysis as Topic; Systematic Reviews as Topic
PubMed: 30611304
DOI: 10.1186/s13195-018-0453-0 -
JAMA Otolaryngology-- Head & Neck... Feb 2018Epidemiologic research on the possible link between age-related hearing loss (ARHL) and cognitive decline and dementia has produced inconsistent results. Clarifying this... (Meta-Analysis)
Meta-Analysis
IMPORTANCE
Epidemiologic research on the possible link between age-related hearing loss (ARHL) and cognitive decline and dementia has produced inconsistent results. Clarifying this association is of interest because ARHL may be a risk factor for outcomes of clinical dementia.
OBJECTIVES
To examine and estimate the association between ARHL and cognitive function, cognitive impairment, and dementia through a systematic review and meta-analysis.
DATA SOURCES AND STUDY SELECTION
A search of PubMed, the Cochrane Library, EMBASE, and SCOPUS from inception to April 15, 2016, with cross-referencing of retrieved studies and personal files for potentially eligible studies was performed. Keywords included hearing, cognition, dementia, and Alzheimer disease. Cohort and cross-sectional studies published in peer-reviewed literature and using objective outcome measures were included. Case-control studies were excluded.
DATA EXTRACTION AND SYNTHESIS
One reviewer extracted and another verified data. Both reviewers independently assessed study quality. Estimates were pooled using random-effects meta-analysis. Subgroup and meta-regression analyses of study-level characteristics were performed.
MAIN OUTCOMES AND MEASURES
Hearing loss measured by pure-tone audiometry only and objective assessment measures of cognitive function, cognitive impairment, and dementia. Cognitive function outcomes were converted to correlation coefficients (r value); cognitive impairment and dementia outcomes, to odds ratios (ORs).
RESULTS
Forty studies from 12 countries met our inclusion criteria. Of these, 36 unique studies with an estimated 20 264 unique participants were included in the meta-analyses. Based on the pooled maximally adjusted effect sizes using random-effects models, a small but significant association was found for ARHL within all domains of cognitive function. Among cross-sectional studies, a significant association was found for cognitive impairment (OR, 2.00; 95% CI, 1.39-2.89) and dementia (OR, 2.42; 95% CI, 1.24-4.72). Among prospective cohort studies, a significant association was found for cognitive impairment (OR, 1.22; 95% CI, 1.09-1.36) and dementia (OR, 1.28; 95% CI, 1.02-1.59) but not for Alzheimer disease (OR, 1.69; 95% CI, 0.72-4.00). In further analyses, study, demographic, audiometric, and analyses factors were associated with cognitive function. Vascular dysfunction and impaired verbal communication may contribute to the association between hearing loss and cognitive decline.
CONCLUSIONS AND RELEVANCE
Age-related hearing loss is a possible biomarker and modifiable risk factor for cognitive decline, cognitive impairment, and dementia. Additional research and randomized clinical trials are warranted to examine implications of treatment for cognition and to explore possible causal mechanisms underlying this relationship.
Topics: Age Factors; Audiometry, Pure-Tone; Cognition; Cognitive Dysfunction; Dementia; Humans; Presbycusis; Risk Factors
PubMed: 29222544
DOI: 10.1001/jamaoto.2017.2513 -
The Cochrane Database of Systematic... Sep 2021Dementia is a common chronic condition, mainly affecting older adults, characterised by a progressive decline in cognitive and functional abilities. Medical treatments... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Dementia is a common chronic condition, mainly affecting older adults, characterised by a progressive decline in cognitive and functional abilities. Medical treatments for dementia are limited. Cannabinoids are being investigated for the treatment of dementia.
OBJECTIVES
To determine the efficacy and safety of cannabinoids for the treatment of dementia.
SEARCH METHODS
We searched ALOIS - the Cochrane Dementia and Cognitive Improvement Group's Specialised Register - on 8 July 2021, using the terms cannabis or cannabinoid or endocannabinoid or cannabidiol or THC or CBD or dronabinol or delta-9-tetrahydrocannabinol or marijuana or marihuana or hashish. The register contains records from all major healthcare databases (the Cochrane Library, MEDLINE, Embase, PsycINFO, CINAHL, LILACS), as well as from many clinical trials registries and grey literature sources.
SELECTION CRITERIA
We included all randomised controlled trials (RCTs) of cannabinoids for the treatment of dementia. We included participants of any age and of either sex with diagnosed dementia of any subtype, or with unspecified dementia of any severity, from any setting. We considered studies of cannabinoids administered by any route, at any dose, for any duration, compared with placebo, no treatment, or any active control intervention.
DATA COLLECTION AND ANALYSIS
Two review authors independently screened and selected studies for inclusion, extracted data, and assessed the risk of bias in included studies. When necessary, other review authors were involved in reaching consensus decisions. We conducted meta-analyses using a generic inverse variance fixed-effect model to derive estimates of effect size. We used GRADE methods to assess our confidence in the effect estimates.
MAIN RESULTS
We included four studies (126 participants) in this review. Most participants had Alzheimer's disease; a few had vascular dementia or mixed dementia. Three studies had low risk of bias across all domains; one study had unclear risk of bias for the majority of domains. The included studies tested natural delta-9-tetrahydrocannabinol (THC) (Namisol) and two types of synthetic THC analogue (dronabinol and nabilone). Three trials had a cross-over design. Interventions were applied over 3 to 14 weeks; one study reported adverse events over 70 weeks of follow-up. One trial was undertaken in the USA, one in Canada, and two in The Netherlands. Two studies reported non-commercial funding, and two studies were conducted with the support of both commercial and non-commercial funding. Primary outcomes in this review were changes in global and specific cognitive function, overall behavioural and psychological symptoms of dementia (BPSD), and adverse events. We found very low-certainty evidence suggesting there may be little or no clinically important effect of a synthetic THC analogue on cognition assessed with the standardised Mini-Mental State Examination (sMMSE) (mean difference (MD) 1.1 points, 95% confidence interval (CI) 0.1 to 2.1; 1 cross-over trial, 28 participants). We found low-certainty evidence suggesting there may be little or no clinically important effect of cannabinoids on overall behavioural and psychological symptoms of dementia assessed with the Neuropsychiatric Inventory (or its modified nursing home version) (MD -1.97, 95% CI -3.87 to -0.07; 1 parallel group and 2 cross-over studies, 110 participants). All included studies reported data on adverse events. However, the total number of adverse events, the total numbers of mild and moderate adverse events, and the total number of serious adverse events (SAEs) were not reported in a way that permitted meta-analysis. There were no clear differences between groups in numbers of adverse events, with the exception of sedation (including lethargy), which was more frequent among participants taking nabilone (N = 17) than placebo (N = 6) (odds ratio (OR) 2.83, 95% CI 1.07 to 7.48; 1 cross-over study, 38 participants). We judged the certainty of evidence for adverse event outcomes to be low or very low due to serious concerns regarding imprecision and indirectness.
AUTHORS' CONCLUSIONS
Based on data from four small, short, and heterogeneous placebo-controlled trials, we cannot be certain whether cannabinoids have any beneficial or harmful effects on dementia. If there are benefits of cannabinoids for people with dementia, the effects may be too small to be clinically meaningful. Adequately powered, methodologically robust trials with longer follow-up are needed to properly assess the effects of cannabinoids in dementia.
Topics: Activities of Daily Living; Aged; Alzheimer Disease; Cannabidiol; Cannabinoids; Dementia, Vascular; Humans
PubMed: 34532852
DOI: 10.1002/14651858.CD012820.pub2 -
The British Journal of Psychiatry : the... May 2013Late-life depression may increase the risk of incident dementia, in particular of Alzheimer's disease and vascular dementia. (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Late-life depression may increase the risk of incident dementia, in particular of Alzheimer's disease and vascular dementia.
AIMS
To conduct a systematic review and meta-analysis to evaluate the risk of incident all-cause dementia, Alzheimer's disease and vascular dementia in individuals with late-life depression in population-based prospective studies.
METHOD
A total of 23 studies were included in the meta-analysis. We used the generic inverse variance method with a random-effects model to calculate the pooled risk of dementia, Alzheimer's disease and vascular dementia in older adults with late-life depression.
RESULTS
Late-life depression was associated with a significant risk of all-cause dementia (1.85, 95% CI 1.67-2.04, P<0.001), Alzheimer's disease (1.65, 95% CI 1.42-1.92, P<0.001) and vascular dementia (2.52, 95% CI 1.77-3.59, P<0.001). Subgroup analysis, based on five studies, showed that the risk of vascular dementia was significantly higher than for Alzheimer's disease (P = 0.03).
CONCLUSIONS
Late-life depression is associated with an increased risk for all-cause dementia, vascular dementia and Alzheimer's disease. The present results suggest that it will be valuable to design clinical trials to investigate the effect of late-life depression prevention on risk of dementia, in particular vascular dementia and Alzheimer's disease.
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Alzheimer Disease; Child; Dementia, Vascular; Depressive Disorder; Female; Humans; Male; Middle Aged; Risk Factors; Young Adult
PubMed: 23637108
DOI: 10.1192/bjp.bp.112.118307 -
The Cochrane Database of Systematic... Mar 2019Memantine is a moderate affinity uncompetitive antagonist of glutamate NMDA receptors. It is licensed for use in moderate and severe Alzheimer's disease (AD); in the... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Memantine is a moderate affinity uncompetitive antagonist of glutamate NMDA receptors. It is licensed for use in moderate and severe Alzheimer's disease (AD); in the USA, it is also widely used off-label for mild AD.
OBJECTIVES
To determine efficacy and safety of memantine for people with dementia. To assess whether memantine adds benefit for people already taking cholinesterase inhibitors (ChEIs).
SEARCH METHODS
We searched ALOIS, the Cochrane Dementia and Cognitive Improvement Group's register of trials (http://www.medicine.ox.ac.uk/alois/) up to 25 March 2018. We examined clinical trials registries, press releases and posters of memantine manufacturers; and the web sites of the FDA, EMEA and NICE. We contacted authors and companies for missing information.
SELECTION CRITERIA
Double-blind, parallel group, placebo-controlled, randomised trials of memantine in people with dementia.
DATA COLLECTION AND ANALYSIS
We pooled and analysed data from four clinical domains across different aetiologies and severities of dementia and for AD with agitation. We assessed the impact of study duration, severity and concomitant use of ChEIs. Consequently, we restricted analyses to the licensed dose (20 mg/day or 28 mg extended release) and data at six to seven months duration of follow-up, and analysed separately results for mild and moderate-to-severe AD.We transformed results for efficacy outcomes into the difference in points on particular outcome scales.
MAIN RESULTS
Across all types of dementia, data were available from almost 10,000 participants in 44 included trials, most of which were at low or unclear risk of bias. For nearly half the studies, relevant data were obtained from unpublished sources. The majority of trials (29 in 7885 participants) were conducted in people with AD.1. Moderate-to-severe AD (with or without concomitant ChEIs). High-certainty evidence from up to 14 studies in around 3700 participants consistently shows a small clinical benefit for memantine versus placebo: clinical global rating (CGR): 0.21 CIBIC+ points (95% confidence interval (CI) 0.14 to 0.30); cognitive function (CF): 3.11 Severe Impairment Battery (SIB) points (95% CI 2.42 to 3.92); performance on activities of daily living (ADL): 1.09 ADL19 points (95% CI 0.62 to 1.64); and behaviour and mood (BM): 1.84 Neuropsychiatric Inventory (NPI) points (95% CI 1.05 to 2.76). There may be no difference in the number of people discontinuing memantine compared to placebo: risk ratio (RR) 0.93 (95% CI 0.83 to 1.04) corresponding to 13 fewer people per 1000 (95% CI 31 fewer to 7 more). Although there is moderate-certainty evidence that fewer people taking memantine experience agitation as an adverse event: RR 0.81 (95% CI 0.66 to 0.99) (25 fewer people per 1000, 95% CI 1 to 44 fewer), there is also moderate-certainty evidence, from three additional studies, suggesting that memantine is not beneficial as a treatment for agitation (e.g. Cohen Mansfield Agitation Inventory: clinical benefit of 0.50 CMAI points, 95% CI -3.71 to 4.71) .The presence of concomitant ChEI does not impact on the difference between memantine and placebo, with the possible exceptions of the BM outcome (larger effect in people taking ChEIs) and the CF outcome (smaller effect).2. Mild AD (Mini Mental State Examination (MMSE) 20 to 23): mainly moderate-certainty evidence based on post-hoc subgroups from up to four studies in around 600 participants suggests there is probably no difference between memantine and placebo for CF: 0.21 ADAS-Cog points (95% CI -0.95 to 1.38); performance on ADL: -0.07 ADL 23 points (95% CI -1.80 to 1.66); and BM: -0.29 NPI points (95% CI -2.16 to 1.58). There is less certainty in the CGR evidence, which also suggests there may be no difference: 0.09 CIBIC+ points (95% CI -0.12 to 0.30). Memantine (compared with placebo) may increase the numbers of people discontinuing treatment because of adverse events (RR 2.12, 95% CI 1.03 to 4.39).3. Mild-to-moderate vascular dementia. Moderate- and low-certainty evidence from two studies in around 750 participants indicates there is probably a small clinical benefit for CF: 2.15 ADAS-Cog points (95% CI 1.05 to 3.25); there may be a small clinical benefit for BM: 0.47 NOSGER disturbing behaviour points (95% CI 0.07 to 0.87); there is probably no difference in CGR: 0.03 CIBIC+ points (95% CI -0.28 to 0.34); and there may be no difference in ADL: 0.11 NOSGER II self-care subscale points (95% CI -0.35 to 0.54) or in the numbers of people discontinuing treatment: RR 1.05 (95% CI 0.83 to 1.34).There is limited, mainly low- or very low-certainty efficacy evidence for other types of dementia (Parkinson's disease and dementia Lewy bodies (for which CGR may show a small clinical benefit; four studies in 319 people); frontotemporal dementia (two studies in 133 people); and AIDS-related Dementia Complex (one study in 140 people)).There is high-certainty evidence showing no difference between memantine and placebo in the proportion experiencing at least one adverse event: RR 1.03 (95% CI 1.00 to 1.06); the RR does not differ between aetiologies or severities of dementia. Combining available data from all trials, there is moderate-certainty evidence that memantine is 1.6 times more likely than placebo to result in dizziness (6.1% versus 3.9%), low-certainty evidence of a 1.3-fold increased risk of headache (5.5% versus 4.3%), but high-certainty evidence of no difference in falls.
AUTHORS' CONCLUSIONS
We found important differences in the efficacy of memantine in mild AD compared to that in moderate-to-severe AD. There is a small clinical benefit of memantine in people with moderate-to-severe AD, which occurs irrespective of whether they are also taking a ChEI, but no benefit in people with mild AD.Clinical heterogeneity in AD makes it unlikely that any single drug will have a large effect size, and means that the optimal drug treatment may involve multiple drugs, each having an effect size that may be less than the minimum clinically important difference.A definitive long-duration trial in mild AD is needed to establish whether starting memantine earlier would be beneficial over the long term and safe: at present the evidence is against this, despite it being common practice. A long-duration trial in moderate-to-severe AD is needed to establish whether the benefit persists beyond six months.
Topics: Activities of Daily Living; Aged; Aged, 80 and over; Akathisia, Drug-Induced; Alzheimer Disease; Cognition Disorders; Dementia; Dementia, Vascular; Excitatory Amino Acid Antagonists; Humans; Memantine; Randomized Controlled Trials as Topic; Withholding Treatment
PubMed: 30891742
DOI: 10.1002/14651858.CD003154.pub6 -
The Cochrane Database of Systematic... Jun 2013Cognitive impairments, particularly memory problems, are a defining feature of the early stages of Alzheimer's disease (AD) and vascular dementia. Cognitive training and... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Cognitive impairments, particularly memory problems, are a defining feature of the early stages of Alzheimer's disease (AD) and vascular dementia. Cognitive training and cognitive rehabilitation are specific interventional approaches designed to address difficulties with memory and other aspects of cognitive functioning. The present review is an update of previous versions of this review.
OBJECTIVES
The main aim of the current review was to evaluate the effectiveness and impact of cognitive training and cognitive rehabilitation for people with mild Alzheimer's disease or vascular dementia in relation to important cognitive and non-cognitive outcomes for the person with dementia and the primary caregiver in the short, medium and long term.
SEARCH METHODS
The CDCIG Specialized Register, ALOIS, which contains records from MEDLINE, EMBASE, CINAHL, PsycINFO, LILACS and many other clinical trial databases and grey literature sources, was most recently searched on 2 November 2012.
SELECTION CRITERIA
Randomised controlled trials (RCTs), published in English, comparing cognitive rehabilitation or cognitive training interventions with control conditions, and reporting relevant outcomes for the person with dementia and/or the family caregiver, were considered for inclusion.
DATA COLLECTION AND ANALYSIS
Eleven RCTs reporting cognitive training interventions were included in the review. A large number of measures were used in the different studies, and meta-analysis could be conducted for 11 of the primary and secondary outcomes of interest. Several outcomes were not measured in any of the studies. The unit of analysis in the meta-analysis was the change from baseline score. Overall estimates of treatment effect were calculated using a fixed-effect model, and statistical heterogeneity was measured using a standard Chi(2) statistic. One RCT of cognitive rehabilitation was identified, allowing examination of effect sizes, but no meta-analysis could be conducted.
MAIN RESULTS
Cognitive training was not associated with positive or negative effects in relation to any reported outcomes. The overall quality of the trials was low to moderate. The single RCT of cognitive rehabilitation found promising results in relation to a number of participant and caregiver outcomes, and was generally of high quality.
AUTHORS' CONCLUSIONS
Available evidence regarding cognitive training remains limited, and the quality of the evidence needs to improve. However, there is still no indication of any significant benefit derived from cognitive training. Trial reports indicate that some gains resulting from intervention may not be captured adequately by available standardised outcome measures. The results of the single RCT of cognitive rehabilitation show promise but are preliminary in nature. Further, well-designed studies of cognitive training and cognitive rehabilitation are required to obtain more definitive evidence. Researchers should describe and classify their interventions appropriately using available terminology.
Topics: Alzheimer Disease; Cognitive Behavioral Therapy; Dementia, Vascular; Humans; Randomized Controlled Trials as Topic
PubMed: 23740535
DOI: 10.1002/14651858.CD003260.pub2 -
The Cochrane Database of Systematic... Jul 2021Dementia is a progressive global cognitive impairment syndrome. In 2010, more than 35 million people worldwide were estimated to be living with dementia. Some people... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Dementia is a progressive global cognitive impairment syndrome. In 2010, more than 35 million people worldwide were estimated to be living with dementia. Some people with mild cognitive impairment (MCI) will progress to dementia but others remain stable or recover full function. There is great interest in finding good predictors of dementia in people with MCI. The Mini-Mental State Examination (MMSE) is the best-known and the most often used short screening tool for providing an overall measure of cognitive impairment in clinical, research and community settings.
OBJECTIVES
To determine the accuracy of the Mini Mental State Examination for the early detection of dementia in people with mild cognitive impairment SEARCH METHODS: We searched ALOIS (Cochrane Dementia and Cognitive Improvement Specialized Register of diagnostic and intervention studies (inception to May 2014); MEDLINE (OvidSP) (1946 to May 2014); EMBASE (OvidSP) (1980 to May 2014); BIOSIS (Web of Science) (inception to May 2014); Web of Science Core Collection, including the Conference Proceedings Citation Index (ISI Web of Science) (inception to May 2014); PsycINFO (OvidSP) (inception to May 2014), and LILACS (BIREME) (1982 to May 2014). We also searched specialized sources of diagnostic test accuracy studies and reviews, most recently in May 2014: MEDION (Universities of Maastricht and Leuven, www.mediondatabase.nl), DARE (Database of Abstracts of Reviews of Effects, via the Cochrane Library), HTA Database (Health Technology Assessment Database, via the Cochrane Library), and ARIF (University of Birmingham, UK, www.arif.bham.ac.uk). No language or date restrictions were applied to the electronic searches and methodological filters were not used as a method to restrict the search overall so as to maximize sensitivity. We also checked reference lists of relevant studies and reviews, tracked citations in Scopus and Science Citation Index, used searches of known relevant studies in PubMed to track related articles, and contacted research groups conducting work on MMSE for dementia diagnosis to try to locate possibly relevant but unpublished data.
SELECTION CRITERIA
We considered longitudinal studies in which results of the MMSE administered to MCI participants at baseline were obtained and the reference standard was obtained by follow-up over time. We included participants recruited and clinically classified as individuals with MCI under Petersen and revised Petersen criteria, Matthews criteria, or a Clinical Dementia Rating = 0.5. We used acceptable and commonly used reference standards for dementia in general, Alzheimer's dementia, Lewy body dementia, vascular dementia and frontotemporal dementia.
DATA COLLECTION AND ANALYSIS
We screened all titles generated by the electronic database searches. Two review authors independently assessed the abstracts of all potentially relevant studies. We assessed the identified full papers for eligibility and extracted data to create two by two tables for dementia in general and other dementias. Two authors independently performed quality assessment using the QUADAS-2 tool. Due to high heterogeneity and scarcity of data, we derived estimates of sensitivity at fixed values of specificity from the model we fitted to produce the summary receiver operating characteristic curve.
MAIN RESULTS
In this review, we included 11 heterogeneous studies with a total number of 1569 MCI patients followed for conversion to dementia. Four studies assessed the role of baseline scores of the MMSE in conversion from MCI to all-cause dementia and eight studies assessed this test in conversion from MCI to Alzheimer´s disease dementia. Only one study provided information about the MMSE and conversion from MCI to vascular dementia. For conversion from MCI to dementia in general, the accuracy of baseline MMSE scores ranged from sensitivities of 23% to 76% and specificities from 40% to 94%. In relationship to conversion from MCI to Alzheimer's disease dementia, the accuracy of baseline MMSE scores ranged from sensitivities of 27% to 89% and specificities from 32% to 90%. Only one study provided information about conversion from MCI to vascular dementia, presenting a sensitivity of 36% and a specificity of 80% with an incidence of vascular dementia of 6.2%. Although we had planned to explore possible sources of heterogeneity, this was not undertaken due to the scarcity of studies included in our analysis.
AUTHORS' CONCLUSIONS
Our review did not find evidence supporting a substantial role of MMSE as a stand-alone single-administration test in the identification of MCI patients who could develop dementia. Clinicians could prefer to request additional and extensive tests to be sure about the management of these patients. An important aspect to assess in future updates is if conversion to dementia from MCI stages could be predicted better by MMSE changes over time instead of single measurements. It is also important to assess if a set of tests, rather than an isolated one, may be more successful in predicting conversion from MCI to dementia.
Topics: Alzheimer Disease; Cognitive Dysfunction; Dementia; Dementia, Vascular; Disease Progression; Early Diagnosis; Frontotemporal Dementia; Humans; Lewy Body Disease; Mental Status and Dementia Tests; Neuropsychological Tests; Sensitivity and Specificity
PubMed: 34313331
DOI: 10.1002/14651858.CD010783.pub3 -
Nutrients Jan 2023Cognitive impairment is a staggering personal and societal burden; accordingly, there is a strong interest in potential strategies for its prevention and treatment.... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Cognitive impairment is a staggering personal and societal burden; accordingly, there is a strong interest in potential strategies for its prevention and treatment. Nutritional supplements have been extensively investigated, and citicoline seems to be a promising agent; its role in clinical practice, however, has not been established. We systematically reviewed studies on the effect of citicoline on cognitive performance.
METHODS
We searched the PubMed and Cochrane Library databases for articles published between 2010 and 2022. Relevant information was extracted and presented following the PRISMA recommendations. Data were pooled using the inverse-variance method with random effects models.
RESULTS
We selected seven studies including patients with mild cognitive impairment, Alzheimer's disease or post-stroke dementia. All the studies showed a positive effect of citicoline on cognitive functions. Six studies could be included in the meta-analysis. Overall, citicoline improved cognitive status, with pooled standardized mean differences ranging from 0.56 (95% CI: 0.37-0.75) to 1.57 (95% CI: 0.77-2.37) in different sensitivity analyses. The overall quality of the studies was poor.
DISCUSSION
Available data indicate that citicoline has positive effects on cognitive function. The general quality of the studies, however, is poor with significant risk of bias in favor of the intervention. Other: PubMed and the Cochrane Library.
Topics: Humans; Cytidine Diphosphate Choline; Alzheimer Disease; Cognitive Dysfunction; Cognition Disorders; Cognition
PubMed: 36678257
DOI: 10.3390/nu15020386