Biomedical subjects

Sastre A Areosa

Publications and source records attributed to Sastre A Areosa.

4 recordsLinked to original sources

PubMed2005

Memantine for dementia.

BACKGROUND: Memantine, a low affinity antagonist to glutamate NMDA receptors, may prevent excitatory neurotoxicity in dementia. OBJECTIVES: To determine efficacy and safety of memantine for people with Alzheimer's disease (AD), vascular (VD) and mixed dementia. SEARCH STRATEGY: The Specialized Register of the Cochrane Dementia and Cognitive Improvement Group was searched on 20 May 2005. This register contains references from all major healthcare databases and many ongoing trial databases and is updated regularly. In addition the search engines Copernic and Google were used to identify unpublished trials through inspection of the websites of licensing bodies like the FDA , EMEA and NICE and of companies' websites (Lundbeck, Merz, Forest, Suntori etc) and clinical trials registries. SELECTION CRITERIA: Double-blind, parallel group, placebo-controlled, randomized trials of memantine in people with dementia. DATA COLLECTION AND ANALYSIS: Data were pooled where possible. Intention-to-treat (ITT) and observed case (OC) analyses are reported. MAIN RESULTS: 1. Moderate to severe AD. Two out of three six month studies show a small beneficial effect of memantine. Pooled data indicate a beneficial effect at six months on cognition (4.12 points on the 100 point SIB , 95% CI 2.14 to 5.74, P < 0.00001), activities of daily living (1.27 points on the 54 point ADCS-ADLsev, 95% CI 0.44 to 2.09, P = 0.003) and behaviour (2.76 points on the 144 NPI, 95% CI 0.88 to 4.63, P = 0.004), supported by clinical impression of change (0.28 points on the 7 point CIBIC+, 95% CI 0.15 to 0.41, P < 0.0001).2. Mild to moderate AD. In a single six month trial, memantine had a beneficial effect on ITT analysis of cognition, (1.9 ADAS-Cog points, 95% CI 0.35 to 3.45, P = 0.02) and behaviour (3.50 NPI points 95% CI 0.15 to 6.85, P = 0.04) supported by clinical global impression of change (0.30 CIBIC+ points, 95% CI 0.09 to 0.51, P = 0.005), but no effect on activities of daily living or OC analysis of cognition. The statistical significance of these benefits could be overturned by data from two unpublished studies which are known to show no significant effect. 3. Mild to moderate vascular dementia. In two six month studies, memantine improved cognition (1.85 ADAS-Cog points, 95% CI 0.88 to 2.83, P = 0.0002), and behaviour (0.84 95% CI 0.06 to 0.91, P = 0.03) but this was not supported by clinical global measures.4. Patients taking memantine appeared to be less likely to develop agitation (93/1167 [8%] versus 134/1141 [12%] (Peto odds ratio (OR): 0.65, 95% CI 0.49 to 0.86, P = 0.002). This was consistently seen in moderate to severe dementia. There were no data which suggested an effect on agitation which is already present.5. Memantine is well tolerated. AUTHORS' CONCLUSIONS: Published data suggest a small beneficial effect of memantine at six months in moderate to severe AD. The beneficial effect on cognition in patients with mild to moderate vascular dementia was not detectable on global assessment at six months. Whether memantine has any effect in mild to moderate AD is unknown.

Activities of Daily Living↗

PubMed2005

Memantine for dementia.

BACKGROUND: Memantine, a low affinity antagonist to glutamate NMDA receptors, may prevent excitatory neurotoxicity in dementia. OBJECTIVES: To determine efficacy and safety of memantine for people with Alzheimer's disease (AD), vascular (VD) and mixed dementia. SEARCH STRATEGY: The Specialized Register of the Cochrane Dementia and Cognitive Improvement Group was searched on 28 October 2004. This register contains references from all major healthcare databases and many ongoing trial databases and is updated regularly. In addition the search engines Copernic and Google were used to identify unpublished trials through inspection of the websites of licensing bodies like the FDA , EMEA an Nice and of companies' websites (Lundbeck, Merz, Forest, Suntori etc). SELECTION CRITERIA: Double-blind, parallel group, placebo-controlled, randomized trials of memantine in people with dementia. DATA COLLECTION AND ANALYSIS: Data were pooled where possible. Intention-to-treat (ITT) and observed case (OC) analyses are reported. MAIN RESULTS: 1. Moderate to severe AD. A major study (MD-01) is unpublished. Published data from two six month studies show a small beneficial effect of memantine at six months on cognition (4.12 SIB points, 95% Confidence Interval (CI) 2.14 to 5.74, P < 0.00001), activities of daily living (1.70 ADCS-ADLsev19 points, 95% CI 0.63 to 2.76, p = 0.002) and behaviour (3.64 NPI points, 95% CI 1.38 to 5.90, p = 0.002), supported by clinical impression of change (0.27 CIBIC+ points, 95% CI 0.10 to 0.43, p = 0.002). The unpublished study would need to have found a detrimental effect of memantine to overturn the statistical significance of the benefits apparent in the two published studies. 2. Mild to moderate AD. In a single six month trial, memantine had a beneficial effect on ITT analysis of cognition, (1.9 ADAS-Cog points, 95% CI 0.35 to 3.43, p = 0.02) and behaviour (3.50 NPI points 95% CI 0.15 to 6.85, p = 0.04) supported by clinical global impression of change (0.30 CIBIC+ points, 95% CI 0.09 to 0.51, p = 0.005), but no effect on activities of daily living or OC analysis of cognition. The statistical significance of these benefits could be overturned by data from two unpublished studies which are known to show no significant effect. 3. Mild to moderate vascular dementia. In two six month studies, memantine improved cognition (1.85 ADAS-Cog points, 95% CI 0.88 to 2.83, p = 0.0002), and behaviour (Weighted Mean Difference (WMD) 0.84 95% CI 0.06 to 0.91, p = 0.03) but this was not supported by clinical global measures.4. Patients taking memantine were less likely to develop agitation (Odds Ratio (OR): 0.65, 95% CI 0.48 to 0.89, p = 0.007). The effect on agitation which is already present is unknown.5. Memantine is well tolerated. AUTHORS' CONCLUSIONS: Published data suggest a small beneficial effect of memantine at six months in moderate to severe AD. The beneficial effect on cognition in patients with mild to moderate vascular dementia was not clinically discernible at six months. Whether memantine has any effect in mild to moderate AD is unknown.

Activities of Daily Living↗

PubMed2003

Memantine for dementia.

BACKGROUND: Alzheimer's disease, vascular and mixed dementia are the commonest forms of dementia in older people. There is evidence that the excitatory activity of L-glutamate plays a role in the pathogenesis of Alzheimer's disease and in the damage from an ischaemic stroke. A low affinity antagonist to N-Methyl-D-aspartate (NMDA) type receptors, such as memantine, may prevent excitatory amino acid neurotoxicity without interfering with the physiological actions of glutamate required for memory and learning. OBJECTIVES: To determine the clinical efficacy and safety of memantine for people with Alzheimer's disease, vascular, or mixed dementia. SEARCH STRATEGY: Trials were identified from a search of the Trial-based Specialized Register of the Cochrane Dementia and Cognitive Improvement Group on 9 October 2002 using the terms: memantin*, D-145, DMAA, DRG-0267. All major health care databases and trial databases within the scope of the group are searched regularly to keep this Register up to date. SELECTION CRITERIA: Double-blind, parallel group, placebo-controlled, randomized and unconfounded trials in which memantine was administered to people with dementia. DATA COLLECTION AND ANALYSIS: Data were extracted, pooled where possible, and weighted mean differences, standardized mean differences or odds ratios were estimated. Intention-to-treat (ITT) and observed cases (OC) analyses are reported, where data were available. MAIN RESULTS: There were a total of seven trials that met inclusion criteria, of which five had sufficient data for analysis. The analysis of change from baseline for cognition gave statistically significant results in favour of memantine (20 mg/day) (MD: -2,83 95% CI -4.37 to -1.29, P=0.0003) at 28 weeks and for memantine (30mg/day) at 6 weeks (MD: -3.04. 95% CI -5.68 to -0.40, P=0.02). Effects on Activities of Daily living (ADL) were difficult to interpret. One study provided data using a non-validated scale for measuring five simple instrumental tasks under the guidance of an investigator. When pooled with another study the analysis gave statistically significant results in favour of memantine for 30 mg/day at 6 weeks (SMD: -1.36 95% CI -1.77 to -0.96, P=0.0003). Mood and behaviour: One trial provided data on memantine 30 mg/day at 6 weeks using the NOSIE scale. The OC analysis found statistically significant differences in favour of treatment (MD: 23.30 95% CI 17.83 to 28.77, P<0.00001). Global scales: The analysis revealed a statistically significant difference in favour of memantine (20mg/day ) at 6 weeks (MD: -12.30 95% CI -16.90 to -7.70, P<0.00001). Similar results were found for larger doses (memantine 30 mg/day) at 6 weeks in a pooled meta-analysis of two other studies (WMD: -10.77 95% CI -13.46 to -8.09, P<0.00001). With regard to the Global Impression of Change three studies found statistically significant results in favour of 10, 20 and 30 mg/day of memantine compared with placebo at 6 or 12 weeks. There was a benefit in favour of memantine (20 mg/day) compared with placebo at 6 weeks, for the numbers improved ( 24/41 compared with 11/41)(OR, 3.85, 95% CI 1.52 to 9.75, P=0.004), in favour of memantine (30 mg/day) compared with placebo at 6 weeks, for the numbers improved ( 20/30 compared with 8/29)(OR, 5.25, 95% CI 1.72 to 15.98, P=0.004) and in favour of memantine (10 mg/day) compared with placebo at 12 weeks, for the numbers improved ( 60/82 compared with 38/84)(OR, 3.30, 95% CI 1.72 to 6.33, P=0.0003). In general memantine seemed to be well tolerated. There was no statistically significant difference between memantine and placebo for the three studies that reported adverse events. There were some data on specific adverse events. In one study the incidence of restlessness by the end of the treatment at 6 weeks was statistically significantly lower in the placebo group than in the group taking memantine 30 mg/day (15/30 compared with 2/29) (OR 13.50, 95% CI 2.71 to 67.19, P=0.001). The number of dropouts was similar in treatment and placebo groups at 6 or 28 weeks time for memantine 20 mg/day and at 6 weeks for memantine 30 mg/day. REVIEWER'S CONCLUSIONS: Memantine is a safe drug and may be useful for treating Alzheimer's, vascular,and mixed dementia of all severities. Most of the trials so far reported have been small and not long enough to detect clinically important benefits. However there is a possible benefit on cognition and global measures, and an early improvement in behaviour in people with dementia. More studies are needed.

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PubMed2003

Folic acid with or without vitamin B12 for cognition and dementia.

BACKGROUND: Folates are vitamins essential to the development of the central nervous system. Insufficient folate activity at the time of conception and early pregnancy can result in congenital neural tube defects. In adult life folate deficiency has been known for decades to produce a characteristic form of anaemia ("megaloblastic"). More recently degrees of folate inadequacy, not severe enough to produce anaemia, have been found to be associated with high blood levels of the amino acid homocysteine. Such degrees of folate inadequacy can arise because of insufficient folates in the diet or because of inefficient absorption or metabolic utilisation of folates due to genetic variations. Conventional criteria for diagnosing folate deficiency may be inadequate for identifying people capable of benefiting from dietary supplementation. High blood levels of homocysteine have been linked with the risk of arterial disease, dementia and Alzheimer's disease. There is therefore interest in whether dietary supplements of folic acid (an artificial chemical analogue of naturally occurring folates) can improve cognitive function of people at risk of cognitive decline associated with ageing or dementia, whether by affecting homocysteine metabolism or through other mechanisms. There is a risk that if folic acid is given to people who have undiagnosed deficiency of vitamin B12 it may lead to neurological damage. Vitamin B12 deficiency produces both an anaemia identical to that of folate deficiency but also causes irreversible damage to the central and peripheral nervous systems. Folic acid will correct the anaemia of vitamin B12 deficiency and so delay diagnosis but will not prevent progression to neurological damage. For this reason trials of folic acid supplements may involve simultaneous administration of vitamin B12. Apparent benefit from folic acid given in the combination would therefore need to be "corrected" for any effect of vitamin B12 alone. A separate Cochrane review of vitamin B12 and cognitive function is being prepared. OBJECTIVES: To examine the effects of folic acid supplementation, with or without vitamin B12, on elderly healthy and demented people, in preventing cognitive impairment or retarding its progress. SEARCH STRATEGY: Trials were identified from a search of the Cochrane Dementia and Cognitive Improvement Specialized Register Group on 9 April 2003 using the terms: folic acid, folate, vitamin B9, leucovorin, methyltetrahydrofolate, vitamin B12, cobalamin, cyanocobalamin, dementia, cognitive function, cognitive impairment, Alzheimer's disease, vascular dementia, mixed dementia and controlled trials. MEDLINE and EMBASE (both all years) were searched for additional trials on healthy people. SELECTION CRITERIA: All double-blind placebo-controlled randomized trials, in which supplements of folic acid with or without vitamin B12 were compared with placebo for elderly healthy people or people with any type of dementia or cognitive impairment. DATA COLLECTION AND ANALYSIS: The reviewers independently applied the selection criteria and assessed study quality. One reviewer extracted and analysed the data. In comparing intervention with placebo, weighted mean differences, and standardized mean difference or odds ratios were estimated. MAIN RESULTS: Four randomized controlled trials fulfilled the inclusion criteria for this review. One trial (Bryan 2002) enrolled healthy women, and three (Fioravanti 1997; Sommer 1998; VITAL 2003) recruited people with mild to moderate cognitive impairment or dementia with or without diagnosed folate deficiency. Fioravanti 1997 enrolled people with mild to moderate cognitive impairment or dementia as judged by scores on the Mini-Mental State Examination (MMSE) and Global Deterioration Scale and with serum folate level<3ng/l. One trial (VITAL 2003) studied the effects of a combination of vitamin B12 and folic acid on patients with mild to moderate cognitive impairment due to Alzheimer's disease or mixed dementia. The analysis from the included trials found no benefit from folic acid with or without vitamin B12 in comparison with placebo on any measures of cognition and mood for healthy or cognitively impaired or demented people: Folic acid effect and healthy participants: there was no benefit from of oral 750 mcg folic acid per day for five weeks compared with placebo on measures of cognition and mood of 19 healthy women aged 65 to 92. Folic acid effect and people with mild to moderate cognitive decline or dementia: there were no statistically significant results in favour of folic acid with or without vitamin B12 on any measures of cognitive function. Scores on the Mini-Mental State Examination (MMSE) revealed no statistically significant benefit from 2 mg per day folic acid plus 1mg vitamin B12 for 12 weeks when compared with placebo (WMD 0.39, 95% CI -0.43 to 1.21, P=0.35). Cognitive scores on the Alzheimer's Disease Scale (ADAS-Cog) showed no statistically significant benefit from 2 mg /day folic acid plus 1 mg /day vitamin B12 for 12 weeks compared with placebo (WMD 0.41, 95% -1.25 to 2.07, P=4.63). The Bristol Activities of Daily Living Scale (BADL) revealed no benefit from 2mg per day of folic acid plus 1 mg vitamin B12 for 12 weeks in comparison with placebo (WMD -0.57, 95%CI -1.95 to 0.81, P=0.42). None of the sub tests of the Randt Memory Test (RMT) showed statistically significant benefit from 15 mg of folic acid orally per day for 9 weeks when compared with placebo. One trial (Sommer 1998) reported a significant decline compared with placebo in two cognitive function tasks in demented patients who had received high doses of folic acid (10 mg /day) for unspecified periods. One trial (VITAL 2003) showed that 2 mg folic acid plus 1 mg vitamin B12 daily for 12 weeks significantly lowered serum homocysteine concentrations (P <0.0001). REVIEWER'S CONCLUSIONS: There was no beneficial effect of 750 mcg of folic acid per day on measures of cognition or mood in older healthy women. In patients with mild to moderate cognitive decline and different forms of dementia there was no benefit from folic acid on measures of cognition or mood. Folic acid plus vitamin B12 was effective in reducing the serum homocysteine concentrations. Folic acid was well tolerated and no adverse effects were reported. More studies are needed.

Cognition↗