The genetic legacy of the 19th-century decline of the British polecat: evidence for extensive introgression from feral ferrets.

In the 19th century, the British polecat suffered a demographic contraction, as a consequence of direct persecution, reaching its lowest population in the years that preceded the First World War. The polecat is now recovering and expanding throughout Britain, but introgressive hybridization with feral ferrets has been reported, which could be masking the true range of the polecat and introducing domestic genes into the species. We used a fragment of the mitochondrial DNA control region and 11 microsatellite loci to characterize the frequency and extent of hybridization and introgression between the two species and assess whether the 19th-century decline corresponded to a genetic bottleneck in the polecat. The proportion of admixture detected in the wild was high (31%) and hybrids were more frequently found outside Wales, suggesting that hybridization is more likely to occur along the eastern edge of the polecat's range expansion. The patterns observed in the mitochondrial and nuclear DNA data show that introgression was mediated by crosses between male polecats and female ferrets, whose offspring backcrossed with polecats. No first-generation (F1 ) hybrids were identified, and the broad range of observed admixture proportions agrees with a scenario of past extensive hybridization between the two species. Using several different methods to investigate demographic history, we did not find consistent evidence for a genetic bottleneck in the British polecat, a result that could be interpreted as a consequence of hybridization with ferrets. Our results highlight the importance of the Welsh polecat population for the conservation and restoration of the genetic identity of the British polecat.

Measurement of spiral artery jets: general principles and differences observed in small-for-gestational-age pregnancies.

OBJECTIVE: To investigate whether the jets of blood from the mouths of the spiral arteries could be measured reliably, as well as their relationship with the uterine artery (UtA) and any differences in small-for-gestational-age (SGA) pregnancies. METHODS: Participants underwent serial ultrasound scans, from 11 weeks' gestation. Pulsatility index (PI) and resistance index (RI) of jets into the intervillous space (IVS) and UtA were recorded at every visit. Intra- and interobserver variability studies were performed. Customized birth weight centiles were calculated and SGA was defined as < 10(th) centile. Linear mixed model analysis was used to allow for the longitudinal nature of the data. RESULTS: Sixty-six women were recruited; 58 remained normotensive and delivered at term. Of these, six women delivered SGA newborns and 52 delivered appropriate-for-gestational-age newborns. All had pulsatile jets until 20 weeks' gestation. The PI and RI of the jets decreased with advancing gestation, following a trend similar to that of the UtAs. There was no correlation between the jets and UtA waveforms when gestational age was controlled for. For intraobserver variability the intraclass correlation coefficient was 0.9. The interobserver study showed no significant difference between the observers. Mixed model analysis demonstrated that PI and RI of jets were different in SGA pregnancies (P < 0.06). This difference was not seen for the UtAs (P = 0.8). CONCLUSION: This technique enables examination of characteristics of the jets of blood flowing from spiral arteries into the IVS. It is both precise and reproducible, with biologically plausible results. Further work is required to assess differences in pregnancies with adverse outcomes.

Reversible infantile respiratory chain deficiency is a unique, genetically heterogenous mitochondrial disease.

OBJECTIVES: Homoplasmic maternally inherited, m.14674T>C or m. 14674T>G mt-tRNA(Glu) mutations have recently been identified in reversible infantile cytochrome c oxidase deficiency (or 'benign COX deficiency'). This study sought other genetic defects that may give rise to similar presentations. PATIENTS: Eight patients from seven families with clinicopathological features of infantile reversible cytochrome c oxidase deficiency were investigated. METHODS: The study reviewed the diagnostic features and performed molecular genetic analyses of mitochondrial DNA and nuclear encoded candidate genes. RESULTS: Patients presented with subacute onset of profound hypotonia, feeding difficulties and lactic acidosis within the first months of life. Although recovery was remarkable, a mild myopathy persisted into adulthood. Histopathological findings in muscle included increased lipid and/or glycogen content, ragged-red and COX negative fibres. Biochemical studies suggested more generalised abnormalities than pure COX deficiency. Clinical improvement was reflected by normalisation of lactic acidosis and histopathological abnormalities. The m.14674T>C mt-tRNA(Glu) mutation was identified in four families, but none had the m. 14674T>G mutation. Furthermore, in two families pathogenic mutations were also found in the nuclear TRMU gene which has not previously been associated with this phenotype. In one family, the genetic aetiology still remains unknown. CONCLUSIONS: Benign COX deficiency is better described as 'reversible infantile respiratory chain deficiency'. It is genetically heterogeneous, and patients not carrying the m.14674T>C or T>G mt-tRNA(Glu) mutations may have mutations in the TRMU gene. Diagnosing this disorder at the molecular level is a significant advance for paediatric neurologists and intensive care paediatricians, enabling them to select children with an excellent prognosis for continuing respiratory support from those with severe mitochondrial presentation in infancy.

WITHDRAWN: Tacrine for Alzheimer's disease.

BACKGROUND: Tacrine is one of the first drugs to be widely marketed for the loss of memory and intellectual decline in Alzheimer's disease, often accompanied by abnormal behaviour and physical decline. The alleged success of tacrine in the treatment of these symptoms has been heralded as confirmation of the cholinergic theory of Alzheimer's disease. The efficacy of tacrine for symptoms of dementia remains controversial. This is reflected by the low rate of prescription of tacrine in countries where it is approved and the lack of approval by several regulatory authorities in Europe and elsewhere. The uncertainty about the efficacy of tacrine is due to the difficulties in interpretation of the results from the clinical trials. The reasons for this are the small effects of tacrine compared to placebo for all outcomes; the high incidence of adverse events; the lack of benefit observed in several trials; the use of cross-over designs and their associated methodological problems in a disease like dementia; the use of different measurement scales to assess outcome in different trials; and the problem of high dropout rates. OBJECTIVES: To determine the clinical efficacy of tacrine for the symptoms of Alzheimer's disease. SEARCH STRATEGY: The Cochrane Dementia Group Register of Clinical Trials was searched using the terms 'tacrine', 'tetrahydroaminoacridine' and 'THA' (see the Group's search strategy for full details). SELECTION CRITERIA: All unconfounded, double-blind, randomized trials in which treatment with tacrine was administered for more than a day and compared to placebo in patients with dementia of the Alzheimer's type. DATA COLLECTION AND ANALYSIS: Data were extracted independently by two reviewers, pooled if appropriate and possible, and the pooled odds ratios (95%CI) or the average differences (95%CI) were estimated. Where possible, intention-to-treat data were used. MAIN RESULTS: This review produced no clear results. The results were compatible with tacrine producing improvement, no change or even harm for those with Alzheimer's disease. It was not possible to use many of the published results in a combined analysis. For measures of overall clinical improvement, the intention-to-treat analyses failed to detect any difference between tacrine and placebo (OR 0.87; 95%CI 0.61 - 1.23). Behavioural disturbance, as measured by the Alzheimer's Disease Assessment Scale-noncognitive, failed to detect any difference between tacrine and placebo (SMD -0.04; 95%CI -0.52 - 0.43). For cognition function, the effect of tacrine was not statistically significantly different from placebo for the MiniMental State Examination score (0-30; high =good) (SMD 0.14; 95%CI -0.02 - 0.30) and was barely statistically significantly in favour of treatment for the Alzheimer's Disease Assessment Scale-cognitive scale (SMD -0.22; 95%CI -0.32 - -0.13). Adverse events were not reported in a systematic way in the different trials, making formal comparison difficult. Raised serum liver enzymes was the major reason for withdrawal. The odds ratio for withdrawal due to an adverse event was significantly different from one, the control group experienced fewer events (OR 5.7; 95%CI 4.1-7.9). Gastrointestinal side effects (diarrhoea, anorexia, dyspepsia and abdominal pain) were the other major cause of adverse events and for withdrawal, and the odds ratio for withdrawal was also significantly different from one in favour of the control group (OR 3.8; 95%CI 2.8-5.1). No deaths were reported in any of the studies during the trial period, up to six months. AUTHORS' CONCLUSIONS: This review provides no convincing evidence that tacrine is a useful treatment for the symptoms of Alzheimer's disease. However, as so few trials presented data in a format suitable for pooling, the results of this review may be modified when further data from all relevant trials are included. There is an urgent need for the independent evaluation of the data already existing in the trials but not accessible through published or grouped data. An independent meta-analysis of the individual-patient data is required. The results and conclusions of this update are unaltered by further searching as the additional studies do not add any further valid/eligible data.

Ginkgo biloba for cognitive impairment and dementia.

BACKGROUND: Extracts of the leaves of the maidenhair tree, Ginkgo biloba, have long been used in China as a traditional medicine for various disorders of health. A standardized extract is widely prescribed for the treatment of a range of conditions including memory and concentration problems, confusion, depression, anxiety, dizziness, tinnitus and headache. The mechanisms of action are thought to reflect the action of several components of the extract and include increasing blood supply by dilating blood vessels, reducing blood viscosity, modification of neurotransmitter systems, and reducing the density of oxygen free radicals. OBJECTIVES: To assess the efficacy and safety of Ginkgo biloba for dementia or cognitive decline. SEARCH STRATEGY: Trials were identified on 10 October 2006 through a search of the Cochrane Dementia and Cognitive Improvement Group's Specialized Register which contains records from all main medical databases (MEDLINE, EMBASE, CINAHL, PsycINFO, SIGLE, LILACS), from ongoing trials databases such as Clinicaltrials.gov and Current Controlled Trials and many other sources. The search terms used were ginkgo*, tanakan, EGB-761, EGB761, "EGB 761" and gingko*. SELECTION CRITERIA: Randomized, double-blind studies, in which extracts of Ginkgo biloba at any strength and over any period were compared with placebo for their effects on people with acquired cognitive impairment, including dementia, of any degree of severity. DATA COLLECTION AND ANALYSIS: Data were extracted from the published reports of the included studies, pooled where appropriate and the treatment effects or the risks and benefits estimated. MAIN RESULTS: Clinical global improvement as assessed by the physician, was dichotomized between participants who showed improvement or were unchanged and those who were worse. There are benefits associated with Ginkgo (dose greater than 200 mg/day) at 24 weeks (207/276 compared with 178/273, OR 1.66, 95% CI 1.12 to 2.46, P=.001) (2 studies), but not for the lower dose. Cognition shows benefit for Ginkgo (any dose) at 12 weeks (SMD -0.65, 95% CI -1.22 to -0.09 P=0.02, 5 studies) but not at 24 weeks. Five studies assessed activities of daily living (ADLs), using different scales. Some scales are more comprehensive than just ADLs. The results show benefit for Ginkgo (dose less than 200 mg/day) compared with placebo at 12 weeks (MD -5.0, 95% CI -7.88, -2.12, p=0.0007, one study), and at 24 weeks (SMD -0.16, 95% CI -0.31 to -0.01, p=0.03, 3 studies) but there are no differences at the higher dose. No study assessed mood and function separately, but one study used the ADAS-Noncog, which assesses function over several domains, but not cognitive function. There was no difference between Ginkgo and placebo. There are no significant differences between Ginkgo and placebo in the proportion of participants experiencing adverse events. There are no data available on Quality of Life, measures of depression or dependency. AUTHORS' CONCLUSIONS: Ginkgo biloba appears to be safe in use with no excess side effects compared with placebo. Many of the early trials used unsatisfactory methods, were small, and we cannot exclude publication bias. The evidence that Ginkgo has predictable and clinically significant benefit for people with dementia or cognitive impairment is inconsistent and unconvincing.

Donepezil for mild cognitive impairment.

BACKGROUND: Problems with memory which do not meet the diagnostic criteria for dementia, usually called mild cognitive impairment (MCI), can be the first sign of an impending dementia, particularly Alzheimer's disease (AD). There is no consensus on a definition or diagnostic criteria for MCI, and MCI remains a vague term and those so described are a heterogeneous population, consisting of people who may rapidly progress to dementia but also of people with stable cognitive deficits and some who may actually improve. Treatment in the very earliest stages of AD may delay progression to AD. Donepezil (Aricept, E2020), a cholinesterase inhibitor, has been shown to benefit all severities of AD including mild and it would be reasonable to investigate its efficacy for those with MCI. OBJECTIVES: To assess the effects of donepezil in people with mild cognitive impairment but no diagnosis of dementia. SEARCH STRATEGY: The trials were identified from a search of the Specialized Register of the Cochrane Dementia and Cognitive Improvement Group on 6 January 2006. This register contains records from major health care databases like CENTRAL, MEDLINE, EMBASE, CINAHL and PsycINFO and many ongoing trial databases and is updated regularly. SELECTION CRITERIA: All double blind, randomized trials in which treatment with donepezil was compared with placebo for patients with mild cognitive impairment. DATA COLLECTION AND ANALYSIS: Data were extracted from the published reports of the included studies, pooled where appropriate and the treatment effects or the risks and benefits estimated. MAIN RESULTS: The two included studies, with a total of 782 patients, all with a MMSE greater than 23 points, identified similar patients for inclusion, but were quite different with respect to design and objective. Pooling results in a meta-analysis was not possible. In the first study the 13-item ADAS-Cog showed benefit associated with 10 mg/day donepezil compared with placebo at 24 weeks (MD 1.90, 95% CI 0.51 to 3.29, p=0.007), but four other measures of cognitive function did not. The analysis of withdrawals before the end of treatment at 24 weeks, withdrawals due to an adverse event, and numbers experiencing an adverse event, showed a significant difference between the donepezil group and the placebo group in favour of placebo, (43/133 donepezil 23/137 placebo, OR 2.37, 95% CI 1.33 to 4.22, p=0.003), (29/133 donepezil 10/137 placebo, OR 3.54, 95% CI 1.65 to 7.60, p=0.001), (116/133 donepezil, 100/137 placebo, OR 2.52 95% CI 1.34 to 4.76, p=0.004). Various adverse effects were recorded, and several types of event, diarrhoea, nausea, vomiting, leg cramps and abnormal dreams, were reported more frequently in the donepezil group compared with the placebo. In the second study there was a significant difference between the number of patients diagnosed with AD or another dementia between the donepezil group and the placebo group in favour of donepezil after one year of treatment (16/253 donepezil 38/259 placebo) (OR 0.39, 95% CI 0.21 to 0.72, p=0.003), but no difference after 3 years of treatment (63/253 donepezil 73/259 placebo) (OR 0.84, 95% CI 0.57 to 1.25, p=0.4). AUTHORS' CONCLUSIONS: There are two included studies. One study demonstrated a modest treatment effect in cognitive function as assessed by ADAS-Cog13 but not for other outcomes assessing different domains of cognitive function. Donepezil was associated with significantly more adverse effects compared with placebo, mostly gastrointestinal. From the second study, there is no evidence that donepezil delays the onset of AD. There is no evidence to support the use of donepezil for patients with MCI. The putative benefits are minor, short lived and associated with significant side effects.

Donepezil for dementia due to Alzheimer's disease.

BACKGROUND: Alzheimer's disease is the most common cause of dementia in older people. One of the aims of therapy is to inhibit the breakdown of a chemical neurotransmitter, acetylcholine, by blocking the relevant enzyme. This can be done by a group of chemicals known as cholinesterase inhibitors. OBJECTIVES: The objective of this review is to assess whether donepezil improves the well-being of patients with dementia due to Alzheimer's disease. SEARCH STRATEGY: The Cochrane Dementia and Cognitive Improvement Group's Specialized Register was searched using the terms 'donepezil', 'E2020' and 'Aricept' on 12 June 2005. This Register contains up-to-date records of all major health care databases and many ongoing trial databases. Members of the Donepezil Study Group and Eisai Inc were contacted. SELECTION CRITERIA: All unconfounded, double-blind, randomized controlled trials in which treatment with donepezil was compared with placebo for patients with mild, moderate or severe dementia due to Alzheimer's disease. DATA COLLECTION AND ANALYSIS: Data were extracted by one reviewer (JSB), pooled where appropriate and possible, and the pooled treatment effects, or the risks and benefits of treatment estimated. MAIN RESULTS: 23 trials are included, involving 5272 participants. Most trials were of 6 months or less duration in selected patients. Available outcome data cover domains including cognitive function, activities of daily living, behaviour , global clinical state and health care resource costs. For cognition there is a statistically significant improvement for both 5 and 10 mg/day of donepezil at 24 weeks compared with placebo on the ADAS-Cog scale (-2.01 points MD, 95%CI -2.69 to -1.34, p<0.00001); -2.80 points, MD 95% CI -3.74 to -2.10, p<0.00001) and for 10 mg/day donepezil compared with placebo at 52 weeks (1.84 MMSE points, 95% CI, 0.53 to 3.15, p=0.006). The results show some improvement in global clinical state (assessed by a clinician) in people treated with 5 and 10 mg/day of donepezil compared with placebo at 24 weeks for the number of patients showing improvement or no change (OR 2.18, 95% CI 1.53 to 3.11, p=<0.0001, OR 2.38, 95% CI 1.78 to 3.19, p<0.00001). Benefits of treatment were also seen on measures of activities of daily living and behaviour, but not on the quality of life score . There were significantly more withdrawals before the end of treatment from the 10 mg/day (but not the 5 mg/day) donepezil group compared with placebo which may have resulted in some overestimation of beneficial changes at 10 mg/day. Benefits on the 10 mg/day dose were marginally larger than on the 5 mg/day dose. Two studies presented results for health resource use, and the associated costs. There were no significant differences between treatment and placebo for any item, the cost of any item, and for the total costs, and total costs including the informal carer costs. A variety of adverse effects were recorded, with more incidents of nausea, vomiting, diarrhoea, muscle cramps, dizziness, fatigue and anorexia (significant risk associated with treatment) in the 10 mg/day group compared with placebo but very few patients left a trial as a direct result of the intervention. AUTHORS' CONCLUSIONS: People with mild, moderate or severe dementia due to Alzheimer's disease treated for periods of 12, 24 or 52 weeks with donepezil experienced benefits in cognitive function, activities of daily living and behaviour. Study clinicians rated global clinical state more positively in treated patients, and measured less decline in measures of global disease severity. There is some evidence that use of donepezil is neither more nor less expensive compared with placebo when assessing total health care resource costs. Benefits on the 10 mg/day dose were marginally larger than on the 5 mg/day dose. Taking into consideration the better tolerability of the 5 mg/day donepezil compared with the 10 mg/day dose, together with the lower cost, the lower dose may be the better option. The debate on whether donepezil is effective continues despite the evidence of efficacy from the clinical studies because the treatment effects are small and are not always apparent in practice .

Galantamine for vascular cognitive impairment.

BACKGROUND: Vascular dementia is the second most common form of dementia. Cholinesterase inhibitors modestly improve a broad range of symptoms in some patients with Alzheimer's disease through enhancement of cholinergic neurotransmission. These drugs may also be beneficial in vascular dementia as reductions in acetylcholine and acetyltransferase activity have been reported. OBJECTIVES: To assess the efficacy of galantamine in the treatment of people with vascular cognitive impairment or vascular dementia or "mixed" dementia. SEARCH STRATEGY: Trials were identified from a search of the Specialized Register of the Cochrane Dementia and Cognitive Improvement Group on 19 April 2005 using the terms: galantamine. galanthamine, reminyl. All major health care databases and many ongoing trial databases within the scope of the group are searched regularly to keep this Register up to date. SELECTION CRITERIA: All unconfounded randomised double-blind trials comparing galantamine with placebo were eligible for inclusion. DATA COLLECTION AND ANALYSIS: Two RCTs fulfilling the inclusion criteria were included in this review. Two reviewers independently extracted the data from these two inclusion studies. MAIN RESULTS: Two trials employing randomized, double-blind, parallel-group methodology were included. GAL-INT-6 reported sub-group data for a pure population of vascular dementia patients showing no significant differences in Alzheimer's Disease Assessment Scale-cognitive subscale (ADAS-cog/11) and Clinician's Interview-based Impression of Change (CIBIC-plus) when galantamine was compared against placebo. When data combining patients with vascular dementia diagnosed according to recognised criteria with a population of patients with Alzheimer's disease and coincidental radiographic findings of cerebrovascular disease was analysed, statistically significant improvements in cognition (ADAS-cog), global functioning (CIBIC-plus), activities of daily living (DAD) and behaviour (NPI) were noted. In the galantamine treated group, significantly higher numbers of patients dropped out and withdrew due to an adverse event. Limited data was available at the time of publication for a second larger trial (GAL-INT-26) involving patients with vascular dementia diagnosed using standard criteria. Statistically significant benefits favouring galantamine over placebo in assessments of cognition (ADAS-cog/11; p < 0.001) and executive function (Executive Interview, EXIT-25, p = 0.041) were recorded. No differences in outcome in measures of behaviour (Neuropsychiatric Inventory, NPI), daily living (Alzheimer's Disease Cooperative Study-Activities of Daily Living inventory, ADCS-ADL) and global functioning (CIBIC-plus) in this trial were seen. AUTHORS' CONCLUSIONS: Limited data were available when considering the impact of galantamine on vascular dementia or vascular cognitive impairment. The data available at the time of review suggest some advantage over placebo in the areas of cognition and executive functioning in one trial but this was not seen in a second trial which included smaller numbers of relevant patients. In both considered trials galantamine produced higher rates of gastrointestinal side-effects. More studies are needed before firm conclusions can be drawn.

Cholinesterase inhibitors for Alzheimer's disease.

BACKGROUND: Since the introduction of the first cholinesterase inhibitor (ChEI) in 1997, most clinicians and probably most patients would consider the cholinergic drugs, donepezil, galantamine and rivastigmine, to be the first line pharmacotherapy for mild to moderate Alzheimer's disease.The drugs have slightly different pharmacological properties, but they all work by inhibiting the breakdown of acetylcholine, an important neurotransmitter associated with memory, by blocking the enzyme acetylcholinesterase. The most that these drugs could achieve is to modify the manifestations of Alzheimer's disease. Cochrane reviews of each ChEI for Alzheimer's disease have been completed (Birks 2005, Birks 2005b and Loy 2005). Despite the evidence from the clinical studies and the intervening clinical experience the debate on whether ChEIs are effective continues. OBJECTIVES: To assess the effects of donepezil, galantamine and rivastigmine in people with mild, moderate or severe dementia due to Alzheimer's disease. SEARCH STRATEGY: The Cochrane Dementia and Cognitive Improvement Group's Specialized Register was searched using the terms 'donepezil', 'E2020' , 'Aricept' , galanthamin* galantamin* reminyl, rivastigmine, exelon, "ENA 713" and ENA-713 on 12 June 2005. This Register contains up-to-date records of all major health care databases and many ongoing trial databases. SELECTION CRITERIA: All unconfounded, blinded, randomized trials in which treatment with a ChEI was compared with placebo or another ChEI for patients with mild, moderate or severe dementia due to Alzheimer's disease. DATA COLLECTION AND ANALYSIS: Data were extracted by one reviewer (JSB), pooled where appropriate and possible, and the pooled treatment effects, or the risks and benefits of treatment estimated. MAIN RESULTS: The results of 13 randomized, double blind, placebo controlled trials demonstrate that treatment for periods of 6 months and one year, with donepezil, galantamine or rivastigmine at the recommended dose for people with mild, moderate or severe dementia due to Alzheimer's disease produced improvements in cognitive function, on average -2.7 points (95%CI -3.0 to -2.3), in the midrange of the 70 point ADAS-Cog Scale. Study clinicians blind to other measures rated global clinical state more positively in treated patients. Benefits of treatment were also seen on measures of activities of daily living and behaviour. None of these treatment effects are large. There is nothing to suggest the effects are less for patients with severe dementia or mild dementia, although there is very little evidence for other than mild to moderate dementia.More patients leave ChEI treatment groups, approximately 29 %, on account of adverse events than leave the placebo groups (18%). There is evidence of more adverse events in total in the patients treated with a ChEI than with placebo. Although many types of adverse event were reported, nausea, vomiting, diarrhoea, were significantly more frequent in the ChEI groups than in placebo. There are four studies, all supported by one of the pharmaceutical companies, in which two ChEIs were compared, two studies of donepezil compared with galantamine, and two of donepezil compared with rivastigmine. In three studies the patients were not blinded to treatment, only the fourth, DON vs RIV/Bullock is double blind. Two of the studies provide little evidence, they are of 12 weeks duration, which is barely long enough to complete the drug titration. There is no evidence from DON vs GAL/Wilcock of a treatment difference between donepezil and galantamine at 52 weeks for cognition, activities of daily living, the numbers who leave the trial before the end of treatment, the number who suffer any adverse event, or any specific adverse event. There is no evidence from DON vs RIV/Bullock of a difference between donepezil and rivastigmine for cognitive function, activities of daily living and behavioural disturbance at two years. Fewer patients suffer adverse events on donepezil than rivastigmine. AUTHORS' CONCLUSIONS: The three cholinesterase inhibitors are efficacious for mild to moderate Alzheimer's disease. It is not possible to identify those who will respond to treatment prior to treatment. There is no evidence that treatment with a ChEI is not cost effective. Despite the slight variations in the mode of action of the three cholinesterase inhibitors there is no evidence of any differences between them with respect to efficacy. There appears to be less adverse effects associated with donepezil compared with rivastigmine. It may be that galantamine and rivastigmine match donepezil in tolerability if a careful and gradual titration routine over more than three months is used. Titration with donepezil is more straightforward and the lower dose may be worth consideration.

Rivastigmine for vascular cognitive impairment.

BACKGROUND: Vascular dementia represents the second most common type of dementia. The classification of vascular dementia broadly follows three clinico-pathological processes: multi-infarct dementia, single strategic infarct dementia and subcortical dementia. As not all victims fulfil strict criteria for dementia and may be significantly cognitively impaired without memory loss, the term vascular cognitive impairment is more useful. Currently, no established standard treatment for vascular cognitive impairment exists. Reductions in acetylcholine and acetyltransferase activity are common to both Alzheimer's disease and vascular cognitive impairment raising the possibility that cholinesterase inhibitors may also be beneficial for the latter. OBJECTIVES: To assess the efficacy of rivastigmine in the treatment of people with vascular cognitive impairment, vascular dementia, or mixed dementia. SEARCH STRATEGY: Trials were searched from the Specialized Register of the Cochrane Dementia and Cognitive Improvement Group on 20 December 2004 using the terms: rivastigmine, exelon, "SDZ ENA 713", SDZ-ENA-713. All major health care databases and many ongoing trial databases within the scope of the Group are searched regularly to keep this Register up to date. SELECTION CRITERIA: All unconfounded randomized double-blind trials comparing rivastigmine with placebo were eligible for inclusion. DATA COLLECTION AND ANALYSIS: No suitable trials were identified and thus we were unable to extract appropriate data or calculate summary statistics. MAIN RESULTS: We were unable to perform a meta-analysis given the absence of suitable trials. Other trials relevant to the field were identified and some indication of benefit in several cognitive and non-cognitive domains were noted. AUTHORS' CONCLUSIONS: From existing trial data there is some evidence of benefit of rivastigmine in vascular cognitive impairment. However, this conclusion is based on studies which had small numbers of patients, which sought to compare rivastigmine to treatments other than placebo or which used data extrapolated post hoc from large studies involving patients with Alzheimer's disease and vascular risk factors of unclear significance. Large placebo-controlled, double blind and adequately randomised trials are needed before firm conclusions can be drawn. The methodology of such trials should acknowledge the biological and clinical features unique to vascular cognitive impairment and its subtypes.

Music therapy for people with dementia.

BACKGROUND: Dementia is a clinical syndrome with a number of different causes which is characterised by deterioration in cognitive functions. Research is pursuing a variety of promising findings for the treatment of dementia. Pharmacological interventions are available but have limited ability to treat many of the syndrome's features. Little research has been directed towards non-pharmacological treatments. In this review the evidence for music therapy as a treatment is examined. OBJECTIVES: To assess the effects of music therapy in the treatment of behavioural, social, cognitive and emotional problems of older people with dementia. SEARCH STRATEGY: The Cochrane Dementia and Cognitive Improvement Group (CDCIG) Specialised Register was searched on 30 June 2003 using the term "music*". This Register contains records from all major health care databases and many ongoing trial databases and is updated regularly. The principal reviewer conducted additional searches to retrieve randomised controlled trials (RCTs) concerning the effect of music therapy on older people with dementia. SELECTION CRITERIA: Randomised controlled trials that reported clinically relevant outcomes associated with music therapy in treatment of behavioural, social, cognitive and emotional problems of older people with dementia. DATA COLLECTION AND ANALYSIS: Two reviewers screened retrieved studies independently for methodological quality using a checklist. Data from accepted studies were independently extracted by the reviewers. MAIN RESULTS: Five studies were included. The methodological quality of the studies was generally poor and the study results could not be validated or pooled for further analyses. REVIEWERS' CONCLUSIONS: The methodological quality and the reporting of the included studies were too poor to draw any useful conclusions.

Velnacrine for Alzheimer's disease.

BACKGROUND: Alzheimer's disease (AD) is the commonest cause of dementia affecting older people. One of the therapeutic strategies aimed at ameliorating the clinical manifestations of Alzheimer's disease is to enhance cholinergic neurotransmission in relevant parts of the brain by the use of cholinesterase inhibitors to delay the breakdown of acetylcholine released into synaptic clefts. Tacrine, the first of the cholinesterase inhibitors to undergo extensive trials for this purpose, was associated with significant adverse effects including hepatotoxicity. Velnacrine is a derivative of tacrine. OBJECTIVES: To determine the clinical efficacy and safety of velnacrine for patients with dementia of Alzheimer's type. SEARCH STRATEGY: The trials were identified from a last updated search of the Specialized Register of the Cochrane Dementia and Cognitive Improvement Group on 8 January 2004 using the terms velnacr* and 'HP 029'. The CDCIG SR is regularly updated and contains records from all major health care databases and a great many ongoing trial databases. SELECTION CRITERIA: All unconfounded, double-blind, randomized trials in which treatment with velnacrine was administered to patients with dementia of the Alzheimer's type for more than two weeks and its effects compared with those of placebo in a parallel group of patients. DATA COLLECTION AND ANALYSIS: One reviewer (JSB) applied study selection criteria, assessed the quality of studies and extracted data. MAIN RESULTS: Four trials, involving 899 participants, were included. Cutler 1990 reported only the adverse events, and omitted the results for the placebo group. Medication was stopped for all in the highest dose group after the fourth day because one member suffered a tonic seizure. It is not possible to report any comparisons with placebo. Antuono 1995 reported benefit for velnacrine at endpoint for the CGI-C, and the Physical Self-maintenance Scale (PGIR), but not for the Carers Assessment of Time Activity (CATS). These results could not be checked because the relevant information was not reported, and we cannot assess the effect on the results of the higher number of non-completers from the velnacrine group. Treatment was discontinued because of safety reasons in 135 patients, mostly due to an abnormal liver function tests. There was a significant difference in favour of placebo compared with the combined treatment group for the number with an abnormal liver function test before the end of treatment at 24 weeks [105/297 vs 4/152, OR =20.23, 95% CI 7.29 to 56.18, p<0.00001]. There was a significant difference in favour of placebo compared with the combined treatment group for the number of withdrawals before the end of treatment at 24 weeks [130/297 vs 39/152, OR =2.26, 95% CI 1.47 to 3.47, p=0.0002]. Results are available for the dose replication phases of Zemlan 1996a and Zemlan 1996b. All the patients had taken velnacrine within two weeks prior to this phase and were identified as responders to velnacrine defined by improvement on the ADAS-Cog. Both studies reported a significant benefit for velnacrine compared with placebo for the ADAS-cog, but the results could not be checked because the relevant information was not reported. Neither study reported any benefit for velnacrine for the other efficacy measures. There was a significant difference in favour of placebo compared with the treatment group for the number with elevated liver transaminases before the end of treatment at 6 weeks [45/153 vs 29/156, OR =1.82, 95% CI 1.07 to 3.11, p=0.03]. There was a significant difference in favour of placebo compared with the treatment group for the number of withdrawals before the end of treatment at 6 weeks [68/211 vs 47/215, OR =1.70, 95% CI 1.10 to 2.62, p=0.02]. REVIEWERS' CONCLUSIONS: There has been no research into the use of velnacrine as a cognitive enhancer in the treatment of Alzheimer's disease since 1994. The FDA peripheral and CNS drug advisory board voted unanimously against recommending approval. This review shows the toxic nature of velnacrine, and provides no evidence of efficacy. There are no grounds for further research into velnacrine.

Donepezil for vascular cognitive impairment.

BACKGROUND: Vascular disease is the second commonest cause of dementia after Alzheimer's disease. There are difficulties in classifying patients with this type of cognitive impairment owing to varied clinical presentation and different types of arterial disease. There is some degree of overlap in the neuropathology of Alzheimer's and vascular dementia. Deficient cholinergic neurotransmission, a characteristic of Alzheimer's disease, has been postulated to contribute to the cognitive impairment of vascular disease of the brain. Cholinesterase inhibitors, such as donepezil, may therefore be a rational treatment. OBJECTIVES: To assess the clinical efficacy and tolerability of donepezil on cognitive function, clinical global impression, activities of daily living and social functioning of people with vascular cognitive impairment. SEARCH STRATEGY: Relevant randomized controlled trials were identified from a search of the Cochrane Dementia and Cognitive Improvement Group Specialized Register on 21 July 2003 using the terms donepezil, E2020 and Aricept. This Register consists of records from all major healthcare databases and many ongoing trials databases. Unpublished trials were requested from the drug company Eisai Inc and they provided us with the required data. SELECTION CRITERIA: All unconfounded randomized double-blind trials comparing donepezil with placebo were eligible for inclusion. Trials using combinations of donepezil with other pharmacological interventions were excluded. DATA COLLECTION AND ANALYSIS: Both reviewers assessed studies against the criteria for inclusion and extracted data. Data were pooled where appropriate, and weighted mean differences or Peto odds ratios with 95% confidence intervals calculated. Intention-to-treat analysis was undertaken when possible. MAIN RESULTS: Two large-scale, randomized, double-blind, parallel-group controlled trials were identified for inclusion. A total of 1219 people with mild to moderate cognitive decline due to probable or possible vascular dementia (according to the NINCDS/AIREN criteria and the Hachinski Ischemia Scale) were recruited. Donepezil, at doses of 5 or 10 mg a day was compared with placebo for 24 weeks. For each outcome measure, mean change from baseline at weeks 12 and 24, using a last observation carried forward analysis, was calculated. Cognitive function: The donepezil groups showed statistically significantly better performance than the placebo groups on the cognitive subscale of the Alzheimer's Disease Assessment Scale (ADAS-Cog) at 12 and 24 weeks. The donepezil groups produced statistically significantly better scores than the placebo groups on the Mini-Mental State Examination (MMSE) at 12 and 24 weeks. Global function: The sum of the boxes of the Clinical Dementia Rating (CDR-SB) showed at 24 weeks a statistically significant benefit of 10 mg donepezil daily over both placebo and a 5 mg daily dosage. The Clinician's Interview-Based Impression of Change-plus version (CIBIC-plus) showed improved global function of participants taking 5 mg of donepezil daily compared with the placebo group but this was not seen in the higher dose group. Activities of daily living and social behaviour: On the Instrumental Activity of Daily Living (IADL) scale, there was no statistically significant difference between the groups taking donepezil 5mg per day donepezil and placebo, but the group taking 10 mg of donepezil a day showed benefit compared with placebo There were statistically significant benefit for donepezil at either dosage compared with placebo on the Alzheimer's Disease Functional Assessment and Change Scale (ADFACS). Tolerability and adverse effects: Broad range of adverse events were reported in the studies and data confirmed that donepezil was well tolerated, and most of the side effects were transient and were resolved by stopping the medication. Some of these events, especially nausea, diarrhoea, anorexia and cramp appeared more frequently on the 10 mg dose where there was a statistically significant difference compared with placebo. Drop-out: The drop-out rate was similar between the groups, 84.2% (330) patients completed the studies. The withdrawal rate was low and due mainly to side effects. REVIEWER'S CONCLUSIONS: Evidence from the available studies support the benefit of donepezil in improving cognition function, clinical global impression and activities of daily living in patients with probable or possible mild to moderate vascular cognitive impairment after 6 months treatment. Extending studies for longer periods would be desirable to establish the efficacy of donepezil in patients with advanced stages of cognitive impairment. Moreover, there is an urgent need for establishing specific clinical diagnostic criteria and rating scales for vascular cognitive impairment.

Vitamin B12 and folate deficiency in later life.

OBJECTIVES: to examine the prevalence of vitamin B12 deficiency and folate deficiency in later life in representative samples of the elderly population in the United Kingdom. DESIGN: a population-based cross-sectional analysis of 3,511 people aged 65 years or older from three studies was used to estimate the age-specific prevalence of vitamin B12 deficiency and of folate deficiency. Vitamin B12 deficiency is conventionally diagnosed if serum vitamin B12 < 150 pmol/l ('low vitamin B12'). We defined 'metabolically significant vitamin B12 deficiency' as vitamin B12 < 200 pmol/l and blood total homocysteine >20 micro mol/l. Folate deficiency, which usually refers to serum folate <5 nmol/l, was defined as 'metabolically significant' if serum folate was <7 nmol/l and homocysteine >20 micro mol/l. RESULTS: the prevalence of vitamin B12 deficiency, whether defined as low vitamin B12 or metabolically significant vitamin B12 deficiency increased with age in all three studies, from about 1 in 20 among people aged 65-74 years to 1 in 10 or even greater among people aged 75 years or greater. The prevalence of folate deficiency also increased with age, and was similar to that for vitamin B12 deficiencies, but only about 10% of people with low vitamin B12 levels also had low folate levels. CONCLUSION: the high prevalence of vitamin B12 and folate deficiency observed in older people indicates a particular need for vigilance for deficiency of these vitamins. Reliable detection and treatment of vitamin deficiency could reduce the risk of deficiency-related disability in old age.

Preliminary evidence from Queensland that rural clinical schools have a positive impact on rural intern choices.

INTRODUCTION: The unequal and inequitable distribution of the medical workforce between rural and urban parts of Australia has been well documented. Commonwealth and state governments have introduced several significant initiatives in an attempt to address this imbalance, including recruitment of many overseas trained doctors. One longer-term initiative is the funding of university departments of rural health and rural clinical schools in medical schools. OBJECTIVE: To determine the impact of the rural clinical division of the School of Medicine at the University of Queensland (UQ), Australia, on the intern workforce in central and southern Queensland, Australia. METHODS: Time series analysis of first preferences for intern allocation among UQ graduates and source of interns (UQ, interstate and overseas) from 2001-2005, and comparison of trends between Rockhampton and Toowoomba (UQ student placements since 2003) with Mackay (no placements). RESULTS: First preferences for Rockhampton increased from six in 2001 to 10 in 2005, and for Toowoomba from five in 2002 to 12 in 2005, while for Mackay preferences were stable at two. At Rockhampton while two interns came from overseas in 2001 and three were from interstate in 2002, UQ provided all interns in 2004 or 2005. UQ has provided 12/13 interns in 2004 and 13/14 in 2005 for Toowoomba. Mackay continues to source interns from interstate and overseas with UQ providing only 3/5 interns in 2004 and 2005. At Rockhampton, among non-bonded UQ graduates the number of interns choosing to work there increased from zero in 2001 to six in 2005. For Toowoomba, numbers were seven and 10 respectively, while for Mackay it was zero. CONCLUSIONS: UQ's rural clinical division is having a positive impact on the intern workforce in the regional hospitals most closely allied with it.

Donepezil for dementia due to Alzheimer's disease.

BACKGROUND: Alzheimer's disease is the most common cause of dementia in older people. One of the aims of therapy is to inhibit the breakdown of a chemical neurotransmitter, acetylcholine, by blocking the relevant enzyme. This can be done by a group of chemicals known as cholinesterase inhibitors. However, some (like tacrine) are associated with adverse effects such as hepatotoxicity, but donepezil (E2020, Aricept) is safer. OBJECTIVES: The objective of this review is to assess whether donepezil improves the well-being of patients with dementia due to Alzheimer's disease. SEARCH STRATEGY: The Cochrane Dementia and Cognitive Improvement Group's Specialized Register was searched using the terms 'donepezil', 'E2020' and 'Aricept' on 9 October 2002. This Register contains up-to-date records of all major health care databases and many ongoing trial databases. Members of the Donepezil Study Group and Eisai Inc were contacted. SELECTION CRITERIA: All unconfounded, double-blind, randomized controlled trials in which treatment with donepezil was compared with placebo for patients with mild, moderate or severe dementia due to Alzheimer's disease. DATA COLLECTION AND ANALYSIS: Data were extracted by one reviewer (JSB ), pooled where appropriate and possible, and the weighted mean differences or Peto odds ratios (95%CI) estimated. MAIN RESULTS: Sixteen trials are included, involving 4365 participants. The trials were of 12, 24 or 52 weeks duration in selected patients. Available outcome data cover domains including cognitive function and global clinical state, but data on several important dimensions of outcome are unavailable. For cognition there is a statistically significant improvement for both 5 and 10 mg/day of donepezil at 24 weeks compared with placebo (-2.02 points on the ADAS-Cog scale WMD, 95%CI -2.77 to -1.26, p<0.00001; -2.92 points on the ADAS-Cog scale WMD 95% CI -3.74 to -2.10, p<0.00001)and for 10 mg/day donepezil compared with placebo at 52 weeks (1.84MMSE points, 95% CI, 0.53 to3.15, p=0.006). The results show some improvement in global clinical state (assessed by an independent clinician) in people treated with 5 and 10 mg/day of donepezil compared with placebo at 12 and 24 weeks. Benefits of treatment were also seen on measures of activities of daily living and behaviour. There were significantly more withdrawals before the end of treatment from the 10 mg/day (but not the 5 mg/day) donepezil group compared with placebo which may have resulted in some overestimation of beneficial changes at 10 mg/day.A variety of adverse effects were recorded, with more incidents of nausea, vomiting, diarrhoea and anorexia in the 10 mg/day group compared with placebo and the 5 mg/day group, but very few patients left a trial as a direct result of the intervention. REVIEWER'S CONCLUSIONS: People with mild, moderate or severe dementia due to Alzheimer's disease treated for periods of 12, 24 or 52 weeks with donepezil experienced benefits in cognitive function, activities of daily living and behaviour. Study clinicians rated global clinical state more positively in treated patients, and measured less decline in measures of global disease severity. Although no significant changes were measured on a patient-rated quality of life scales, the instrument used was crude and possibly unsuited to the task. The additional data now available confirm the findings of the previous issue of this review and extend the evidence for the effectiveness of treatment to at least 52 weeks and to those with severe dementia. More evidence is still needed for the economic efficacy of donepezil, but clinical efficacy is confirmed.

Selegiline for Alzheimer's disease.

BACKGROUND: Alzheimer's disease is the most common cause of dementia in older people accounting for some 60% of cases with late-onset cognitive deterioration. It is now thought that several neurotransmitter dysfunctions are involved from an early stage in the pathogenesis of Alzheimer's disease-associated cognitive decline. The efficacy of selegiline for symptoms of Alzheimer's disease remains controversial and is reflected by its low rate of prescription and the lack of approval by several regulatory authorities in Europe and elsewhere. Reasons for this uncertainty involve the modest overall effects observed in some trials, the lack of benefit observed in several trials, the use of cross-over designs which harbour methodological problems in a disease like dementia and the difficulty in interpreting results from trials when a variety of measurement scales are used to assess outcomes. OBJECTIVES: The objective of this review is to assess whether or not selegiline improves the well-being of patients with Alzheimer's disease. SEARCH STRATEGY: The Cochrane Dementia and Cognitive Impairment Group Register of Clinical Trials, was searched using the terms 'selegiline', 'l-deprenyl', "eldepryl" and "monamine oxidase inhibitor-B". MEDLINE, PsycLIT and EMBASE electronic databases were searched with the above terms in addition to using the group strategy (see group details) to limit the searches to randomised controlled trials. SELECTION CRITERIA: All unconfounded, double-blind, randomised controlled trials in which treatment with selegiline was administered for more than a day and compared to placebo in patients with dementia. DATA COLLECTION AND ANALYSIS: An individual patient data meta-analysis of selegiline, Wilcock 2002 provides much of the data that are available for this review. Seven studies provided individual patient data and this was pooled with summary statistics from the published papers of the other nine studies. Where possible, intention-to-treat data were used but usually the meta analyses were restricted to completers' data (data on people who completed the study). MAIN RESULTS: There are 17 included trials. There were very few significant treatment effects and these were all in favour of selegiline; cognition at 4-6 weeks and 8-17 weeks, and activities of daily living at 4-6 weeks. There is little evidence of adverse effects caused by selegiline, and few withdrew from trials, apart from the Sano trial. The analyses were conducted on data available. There was no attempt to correct for missing patients because there were so few and withdrawal was probably unconnected with treatment. All trials examined the cognitive effects of selegiline, and in addition 12 trials examined the behavioural and mood effects. The meta-analysis revealed benefits on memory function, shown by improvement in the memory tests from several cognitive tests (the Randt Memory Index from Agnoli 1990 and Agnoli 1992, the BSRT from Sunderland 1992, prose recall from Filip 1991, ADAS-cog from Lawlor 1997, the Wechsler Memory Scale from Loeb 1990 and Mangoni 1991, the Rey -AVL from Piccinin 1990, and the MMSE from Sano 1995, Tariot 1998, Filip 1991, Freedman 1996, Burke 1993 and Riekkinen 1993). The combined memory tests, and overall the combined cognitive tests, analysed using standardised mean differences, showed an improvement due to selegiline compared with placebo at 4-6 weeks (SMD 0.39, 95%CI 0.07 to 0.72, P = 0.02, random effects model ) and 8-17 weeks, ( SMD 0.44, 95%CI 0.04 to 0.84, P = 0.03, random effects model). The meta-analyses of emotional state show no treatment effects. Several studies assessed activities of daily living using several different scales, the GBS-motor function from Agnoli 1990, the NOSIE-daily living from Filip 1991, the BDS-daily living from Loeb 1990 and Mangoni 1991, the DS from Sano 1995 and PIADL from Tariot 1998. The combined tests, analysed using the standardised mean difference, showed an improvement due to selegiline at 4-6 weeks (SMD -0.27, 95% CIs -0.41 to -0.13, P = <.001). The global rating scales, the BDS used by Burke 1993 and Tariot 1998, and the GBS used by Agnoli 1990 and Agnoli 1992, and the GDS used by Freedman 1996 and the CGI by Filip 1991, analysed using standardised mean differences showed no effect of selegiline. A variety of adverse effects were recorded, but very few patients left a trial as a direct result. Four studies reported no side effects. Mangoni 1991 reported poor tolerability for 3 patients out of 68 on treatment and 1 out of 51 on placebo, resulting in dropouts. Small numbers found equally in both groups reported anxiety, agitation, dizziness, nausea and dyspepsia. Piccinin 1990 reported that selegiline was well tolerated with few adverse reactions (dizziness and orthostatic hypotension) and no resulting drop outs. Burke 1993 and Loeb 1990 both reported that selegiline was very well tolerated with no serious side effects. Sano 1995 reported 49 categories of adverse events but found no differences between the 4 arms of the factorial trial. Freedman 1996 reported unequal numbers of dropouts in the trial with 7 subjects withdrawing from the selegiline group and only 1 subject from the placebo group. The meta-analyses of the numbers suffering adverse effects, and of the numbers of withdrawals before the end of the trial show no difference between control and selegiline. REVIEWER'S CONCLUSIONS: Despite its initial promise, ie the potential neuroprotective properties, and its role in the treatment of Parkinson's disease sufferers, selegiline for Alzheimer's disease has proved disappointing. Although there is no evidence of a significant adverse event profile, there is also no evidence of a clinically meaningful benefit for Alzheimer's disease sufferers. This is true irrespective of the outcome measure evaluated, ie cognition, emotional state, activities of daily living, and global assessment, whether in the short, or longer term (up to 69 weeks), where this has been assessed. There would seem to be no justification, therefore, to use it in the treatment of people with Alzheimer's disease, nor for any further studies of its efficacy in Alzheimer's disease.

Spatial and temporal analysis of second-generation anticoagulant rodenticide residues in polecats (Mustela putorius) from throughout their range in Britain, 1992-1999.

Polecats (Mustela putorius) in Britain are currently expanding their range eastwards from Wales to reoccupy central and eastern areas of England. Second-generation anticoagulant rodenticides (SGARs), to which polecats are exposed by eating contaminated prey, are used more extensively in these central and eastern regions, leading to fears of increased exposure, and possible resultant mortality. We measured bromadiolone, difenacoum, flocoumafen and brodifacoum concentrations in the livers of 50 polecats from areas that included newly recolonised habitats and found that at least one SGAR was detected in the livers of 13 out of 37 (35.1%) male and 5 out of 13 (38.5%) female polecats. Difenacoum and bromadiolone were detected most frequently. We then combined these data with measurements on another 50 individuals from earlier studies to create a dataset for 100 polecats collected throughout the 1990s from across the whole of their current range. Using this dataset, we determined if there was any evidence that contamination in polecats had increased during the 1990s and whether animals from England were more contaminated than those from Wales, as might be expected given regional differences in the patterns of SGAR use. Overall, 31 of the 100 polecats analysed to date contained SGAR residues. The incidence was a little higher (40%) in animals that died between January and June and this probably better reflects the overall proportion of animals that are sub-lethally exposed. There was no statistically significant change during the 1990s in the proportion of polecats exposed to SGARs nor any evidence that greater use of SGARs in England resulted in more contamination of polecats. Contrary to expectation, the proportion of animals that contained difenacoum was marginally higher in Wales than elsewhere.

Nimodipine for primary degenerative, mixed and vascular dementia.

BACKGROUND: Dementia is an age-associated syndrome most commonly due to Alzheimer's disease (AD) and/or cerebrovascular disease. Calcium has an important role in regulating brain functions. Calcium ions link membrane excitation to subsequent intracellular molecular responses. Age-associated changes in calcium homoeostasis have possible repercussions on higher cortical functions. Nimodipine is an isopropyl calcium channel blocker which readily crosses the blood-brain barrier. Its primary action is to reduce the number of open calcium channels in cell membranes, thus restricting influx of calcium ions into cells. The usefulness of nimodipine in patients with Alzheimer's disease and vascular dementia and unspecified dementia is still controversial. In spite of the uncertainties about its efficacy in dementia, nimodipine is currently frequently prescribed for cognitive impairment and dementia in several continental European countries. OBJECTIVES: To assess the clinical efficacy of nimodipine for the manifestations of dementia, in unclassified disease and in the major subtypes - Alzheimer's disease, cerebrovascular disease, and mixed Alzheimer's and cerebrovascular disease. SEARCH STRATEGY: The Cochrane Dementia and Cognitive Improvement Group's Specialized Register - which contains reports of trials from all major medical databases and many trial databases - was last searched on 3 August 2001 using the term 'nimodipin*'. SELECTION CRITERIA: All unconfounded, double-blind, randomized trials in which treatment with nimodipine was administered for more than a day and compared with placebo in patients with dementia, of unclassified type or attributable to Alzheimer's disease, cerebrovascular disease, or mixed Alzheimer's and cerebrovascular disease. DATA COLLECTION AND ANALYSIS: Data were extracted independently by the reviewers and the odds ratio (95%CI) or the average difference (95%CI) were estimated. Both intention-to-treat and on-treatment results were extracted. MAIN RESULTS: Fourteen trials were included which tested two treatment regimes, 90 and 180 mg/day of nimodipine for 12 and 24 weeks. Two trials included only patients with Alzheimer's disease (AD), 9 trials included only patients with cerebrovascular dementia (CVD), and three trials included patients with AD, CVD and mixed disease. Available outcome data from 9 trials (2492 patients) cover the domains of cognitive function, activities of daily living, global clinical state, safety and tolerability. By pooling available data from all trials, whatever the diagnosis of the patients included, this review found benefit associated with nimodipine (90 mg/day at 12 weeks) compared with placebo on the SCAG scale ( WMD -7.59, 95% CI -9.87 to -5.31, P<0.00001) on clinical global impression (WMD -0.87, 95% CI -1.07 to -0.67, P<0.00001) and cognitive function (SMD 0.61, 95% CI 0.42 to 0.81, P<0.00001) but not on scales assessing activities of daily living. When the AD trials and the VD trials were pooled separately similar significant results were found for the 90mg/day dose of nimodipine at 12 weeks. Drop-out rates were low in the trials, affecting similar proportions of treatment and placebo groups. Nimodipine is well tolerated with a low rate of adverse effects similar to that associated with placebo. There were slightly more adverse cerebrovascular events, and adverse events due to blood problems, associated with placebo than with nimodipine, and adverse autonomic events were slightly more common with nimodipine than with placebo. REVIEWER'S CONCLUSIONS: Nimodipine can be of some benefit in the treatment of patients with features of dementia due to unclassified disease or to Alzheimer's disease, cerebrovascular disease, or mixed Alzheimer's and cerebrovascular disease. It appears to be well tolerated with few side effects. Data were not available from several trials, a total of more than 500 patients. A meta-analysis of individual patient data from all trials is desirable. Dementia is a chronic disorder and the short-term benefits of nimodipine demonstrated in the trials reviewed do not justify its use as a long-term anti-dementia drug. New research must focus on longer term outcomes.

The effect of selegiline in the treatment of people with Alzheimer's disease: a meta-analysis of published trials.

OBJECTIVE: To evaluate the effect of selegiline in the treatment of patients with Alzheimer's disease, in terms of cognitive performance, functional ability, emotional state (including behaviour and mood) and global response. Data Sources The Cochrane database of trials, Embase, Medline and Psychlit. Study Selection Unconfounded, double-blind, randomised trials of selegiline compared with placebo reported before 31 December 1998. Data Extraction The reviewers selected trials for inclusion. Individual patient data were sought, but when these could not be retrieved summary data were extracted from published papers. RESULTS: Of 27 identified trials, 14 met the inclusion criteria. Individual patient data were retrieved from eight trials on 821 patients. Summary data were extracted from five trials on 240 patients. No data were available from one trial on 12 patients, which was therefore excluded from the meta-analysis. Fixed and random effects meta-analyses were performed on standardised mean differences. For cognition there was a statistically significant difference between selegiline and placebo at 4-6 weeks and 8-17 weeks after randomisation (at 8-17 weeks: smd=0.45 [95% confidence interval 0.03 to 0.88]), but this disappeared at later assessments. The size of the treatment difference was considered unlikely to be of clinical importance. Although there was a statistically significant difference at 4-6 weeks for activities of daily living, this disappeared at later assessments (at 8-17 weeks: smd=0.33 [-0.33, 0.69]). There were no statistically significant differences or clinically relevant differences between selegiline and placebo in terms of emotional state or global response. CONCLUSION: Although there was some evidence of improvement with selegiline in the short term in cognition and activities of daily living, the magnitude of the effect did not reach clinical importance. There was no evidence of long term effects.