Abstract:
BACKGROUND:Micronutrient status can affect cognitive function at all ages. Vitamin deficiencies could influence memory function and might contribute to age-associated cognitive impairment and dementia. Vitamin B6, comprising three chemically distinct compounds pyridoxal, pyridoxamine, and pyridoxine, is involved in the regulation of mental function and mood. Vitamin B6 is also an essential homocysteine re-methylation cofactor, and deficiency is associated with increase in blood homocysteine levels. Homocysteine is a risk factor for cerebrovascular disease and may also have directly toxic effects on neurons of the central nervous system. Neuropsychiatric disorders including seizures, migraine, chronic pain and depression have been linked to vitamin B6 deficiency. Epidemiological studies indicate that poor vitamin B6 status is common among older people. Hyperhomocysteinaemia has been suggested as a cause or mechanism in the development Alzheimer's disease and other forms of dementia. Supplementation with B vitamins including vitamin B6 has been shown to reduce blood homocysteine levels. OBJECTIVES:To assess the efficacy of vitamin B6 supplementation in reducing the risk of developing cognitive impairment by older healthy people, or improving cognitive functioning of people with cognitive decline and dementia, whether or not vitamin B6 deficiency has been diagnosed. SEARCH STRATEGY:The Specialized Register of the Cochrane Dementia and Cognitive Improvement Group was searched on 20 May 2003 using the terms: vitamin B6, pyridoxine, pyridoxamine, pyridoxal. For relevant trials on healthy elderly people MEDLINE, EMBASE and CENTRAL were searched using the previously mentioned terms as well as the term cognit * SELECTION CRITERIA:All unconfounded, double-blind randomized controlled trials in which the intervention with vitamin B6 was compared with placebo for healthy older people or people with cognitive decline or dementia. The primary outcome of interest was the efficacy of vitamin B6 supplementation on cognitive function. DATA COLLECTION AND ANALYSIS:The two reviewers independently evaluated all studies identified as possibly meeting the criteria for inclusion. One reviewer independently extracted the data. Studies were rated for their overall quality. The weighted mean differences between treatment and placebo groups, with 95% confidence intervals, were calculated for each outcome. Review Manager version 4.2 was used to analyse the variance. MAIN RESULTS:No trials of vitamin B6 involving people with cognitive impairment or dementia were found. The two trials included in the review (Bryan 2002; Deijen 1992) used a double-blind, randomized, placebo-controlled design and involved 109 healthy older people. One trial restricted enrolment to women and the other to men. Vitamin B6 supplementation and healthy older women: Bryan 2002 enrolled 211 healthy women from various age groups into a 5-week study. The trial was of multifactorial design with folic acid, vitamin B12, vitamin B6 and placebo in its four arms. Twelve healthy women aged 65 to 92 years received 75 mg vitamin B6 orally per day and were compared with 21 healthy women who were allocated to placebo. No statistically significant benefits from vitamin B6 on mood or cognition were observed. Vitamin B6 supplementation and healthy older men: Deijen 1992 recruited 76 healthy men aged 70 to 79 years. They were divided into 38 matched pairs, one member of each pair randomly allocated to 20 mg of vitamin B6 (pyridoxine hydrochloride) per day for 12 weeks the other to placebo. No statistically significant differences between treatment and placebo were found in their effects on cognition or mood. Effect of vitamin B6 supplementation on vitamin B6 status: Deijen 1992 reported that 20 mg of pyridoxine hydrochloride per day for 12 weeks increased blood vitamin B6 activity as assessed as by plasma pyridoxal-5'-phosphate (WMD 238, 95%CI 211.58 to 264.42, P<0.00001) and erythrocyte enzyme asparate aminotransferase (WMD 0.43, 95%CI 0.30 to 0.56, P<0.00001). Effect of vitamin B6 supplementation on blood homocysteine concentration: Neither of the included trials measured homocysteine levels. Drop-outs: All participants allocated to vitamin B6 or placebo completed the trial protocol. Adverse Events: No adverse effects were reported. Effect of vitamin B6 on carer burden, care costs and institutionalization rate: We found no trials in which these outcomes were assessed. REVIEWER'S CONCLUSIONS:This review found no evidence for short-term benefit from vitamin B6 in improving mood (depression, fatigue and tension symptoms) or cognitive functions. For the older people included in one of the two trials included in the review, oral vitamin B6 supplements improved biochemical indices of vitamin B6 status, but potential effects on blood homocysteine levels were not assessed in either study. This review found evidence that there is scope for increasing some biochemical indices of vitamin B6 status among older people. More randomized controlled trials are needed to explore possible benefits from vitamin B6 supplementation for healthy older people and those with cognitively impairment or dementia.
journal_name
Cochrane Database Syst Revjournal_title
The Cochrane database of systematic reviewsauthors
Malouf R,Grimley Evans Jdoi
10.1002/14651858.CD004393keywords:
subject
Has Abstractpub_date
2003-01-01 00:00:00pages
CD004393issue
4issn
1469-493Xpub_type
杂志文章,评审abstract:BACKGROUND:Extracranial internal carotid artery dissection can lead to occlusion of the artery and hence cause an ischemic stroke. It is the underlying stroke mechanism in approximately 2.5% of all strokes, and the second leading cause of stroke in patients younger than 45 years of age. Antithrombotic agents (heparin, ...
journal_title:The Cochrane database of systematic reviews
pub_type: 杂志文章,评审
doi:10.1002/14651858.CD000255
更新日期:2000-01-01 00:00:00
abstract:BACKGROUND:Problems in inducing ovulation in women with polycystic ovary syndrome (PCOS) and anovulation (failure to ovulate) are well recognised. Surgical ovarian wedge resection was the first established treatment for anovulatory PCOS patients but was largely abandoned because of the risk of post-surgical adhesion fo...
journal_title:The Cochrane database of systematic reviews
pub_type: 杂志文章,评审
doi:10.1002/14651858.CD001122
更新日期:2001-01-01 00:00:00
abstract:BACKGROUND:Critical appraisal is the process of assessing and interpreting evidence by systematically considering its validity, results and relevance to an individual's work. Within the last decade critical appraisal has been added as a topic to many medical school and UK Royal College curricula, and several continuing...
journal_title:The Cochrane database of systematic reviews
pub_type: 杂志文章,评审
doi:10.1002/14651858.CD001270.pub2
更新日期:2011-11-09 00:00:00
abstract:BACKGROUND:Endometriosis is known to have an impact on fertility and it is common for women affected by endometriosis to require fertility treatments, including in vitro fertilisation (IVF) or intracytoplasmic sperm injection (ICSI), to improve the chance of pregnancy. It has been postulated that long-term gonadotrophi...
journal_title:The Cochrane database of systematic reviews
pub_type: 杂志文章,meta分析
doi:10.1002/14651858.CD013240.pub2
更新日期:2019-11-20 00:00:00
abstract:BACKGROUND:Chronic excessive alcohol consumption may lead to dependence, and to alcohol withdrawal syndrome (AWS) in case of abrupt drinking cessation. Gamma-hydroxybutyric acid (GHB) can prevent and suppress withdrawal symptoms, and improve the medium-term abstinence rate. A clear balance between effectiveness and har...
journal_title:The Cochrane database of systematic reviews
pub_type: 杂志文章,meta分析,评审
doi:10.1002/14651858.CD006266.pub2
更新日期:2010-02-17 00:00:00
abstract:BACKGROUND:Sexual dysfunction (including altered desire, orgasmic dysfunction, erectile and ejaculatory problems) is a relatively common side effect of antidepressant medication. These sexual side effects may compromise a person's lifestyle and result in a lack of compliance with the prescribed antidepressant to the de...
journal_title:The Cochrane database of systematic reviews
pub_type: 杂志文章,meta分析,评审
doi:10.1002/14651858.CD003382.pub2
更新日期:2004-10-18 00:00:00
abstract:BACKGROUND:Chronic severe infection with Pseudomonas aeruginosa, affects many people with cystic fibrosis (CF). There is evidence from the laboratory and from other disease processes that macrolide antibiotics, whilst not directly active against Pseudomonas aeruginosa, may have indirect actions against this organism. ...
journal_title:The Cochrane database of systematic reviews
pub_type: 杂志文章,评审
doi:10.1002/14651858.CD002203.pub2
更新日期:2004-01-01 00:00:00
abstract:BACKGROUND:Indomethacin is used as standard therapy to close a patent ductus arteriosus (PDA) but is associated with reduced blood flow to several organs. Ibuprofen, another cyclo-oxygenase inhibitor, may be as effective as indomethacin with fewer side effects. OBJECTIVES:To determine the efficacy and safety of ibupro...
journal_title:The Cochrane database of systematic reviews
pub_type: 杂志文章,meta分析,评审
doi:10.1002/14651858.CD003481.pub5
更新日期:2013-04-30 00:00:00
abstract:BACKGROUND:Chronic wounds mainly affect the elderly and those with multiple health problems. Despite the use of modern dressings, some of these wounds take a long time to heal, fail to heal, or recur, causing significant pain and discomfort to the person and cost to health services. Topical negative pressure (TNP) is u...
journal_title:The Cochrane database of systematic reviews
pub_type: 杂志文章,meta分析,评审
doi:10.1002/14651858.CD001898.pub2
更新日期:2008-07-16 00:00:00
abstract:BACKGROUND:Progesterone prepares the endometrium for pregnancy by stimulating proliferation in response to human chorionic gonadotropin (hCG), which is produced by the corpus luteum. This occurs in the luteal phase of the menstrual cycle. In assisted reproduction techniques (ART) the progesterone or hCG levels, or both...
journal_title:The Cochrane database of systematic reviews
pub_type: 杂志文章,meta分析,评审
doi:10.1002/14651858.CD009154.pub2
更新日期:2011-10-05 00:00:00
abstract:BACKGROUND:Surgical bypass of an occluded arterial segment is the mainstay of treatment for patients with critical limb ischaemia. As with many surgical interventions, however, it was introduced without formal evaluation. OBJECTIVES:The objective of this review was to determine the effects of bypass surgery in patient...
journal_title:The Cochrane database of systematic reviews
pub_type: 杂志文章,评审
doi:10.1002/14651858.CD002000
更新日期:2000-01-01 00:00:00
abstract:BACKGROUND:People with asthma who come from minority groups often have poorer asthma outcomes, including more acute asthma-related doctor visits for flare-ups. Various programmes used to educate and empower people with asthma have previously been shown to improve certain asthma outcomes (e.g. adherence outcomes, asthma...
journal_title:The Cochrane database of systematic reviews
pub_type: 杂志文章,meta分析,评审
doi:10.1002/14651858.CD006580.pub5
更新日期:2017-08-22 00:00:00
abstract:BACKGROUND:Short term side-effects of chemotherapy include fatigue, nausea, vomiting, mucositis and myelosuppression or neutropenia. These occur during the course of treatment and generally resolve within months of completion of chemotherapy. A variety of Chinese medicinal herbs have been used for managing these side e...
journal_title:The Cochrane database of systematic reviews
pub_type: 杂志文章,meta分析,评审
doi:10.1002/14651858.CD004921.pub2
更新日期:2007-04-18 00:00:00
abstract:BACKGROUND:Strongyloidiasis is a gut infection with Strongyloides stercoralis which is common world wide. Chronic infection usually causes a skin rash, vomiting, diarrhoea or constipation, and respiratory problems, and it can be fatal in people with immune deficiency. It may be treated with ivermectin or albendazole or...
journal_title:The Cochrane database of systematic reviews
pub_type: 杂志文章,meta分析,评审
doi:10.1002/14651858.CD007745.pub3
更新日期:2016-01-18 00:00:00
abstract:BACKGROUND:Cataract is a leading cause of blindness worldwide. Cataract surgery is commonly performed but can result in postoperative inflammation of the eye. Inadequately controlled inflammation increases the risk of complications. Non-steroidal anti-inflammatory drugs (NSAIDs) and corticosteroids are used to prevent ...
journal_title:The Cochrane database of systematic reviews
pub_type: 杂志文章,meta分析,评审
doi:10.1002/14651858.CD010516.pub2
更新日期:2017-07-03 00:00:00
abstract:BACKGROUND:Several studies have suggested that prophylactic antibiotics given during pregnancy improved maternal and perinatal outcomes, while others have shown no benefit and some have reported adverse effects. OBJECTIVES:To determine the effect of prophylactic antibiotics on maternal and perinatal outcomes during th...
journal_title:The Cochrane database of systematic reviews
pub_type: 杂志文章,meta分析,评审
doi:10.1002/14651858.CD002250.pub2
更新日期:2015-01-26 00:00:00
abstract:BACKGROUND:Bronchiectasis is a long term respiratory condition with an increasing rate of diagnosis. It is associated with persistent symptoms, repeated infective exacerbations, and reduced quality of life, imposing a burden on individuals and healthcare systems. The main aims of therapeutic management are to reduce ex...
journal_title:The Cochrane database of systematic reviews
pub_type: 杂志文章,meta分析,评审
doi:10.1002/14651858.CD012528.pub2
更新日期:2018-02-07 00:00:00
abstract:BACKGROUND:A giant retinal tear (GRT) is a full-thickness neurosensory retinal break extending for 90° or more in the presence of a posterior vitreous detachment. OBJECTIVES:To evaluate the effectiveness and safety of pars plana vitrectomy combined with scleral buckle versus pars plana vitrectomy alone for eyes with g...
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pub_type: 杂志文章,meta分析
doi:10.1002/14651858.CD012646.pub2
更新日期:2019-12-16 00:00:00
abstract:BACKGROUND:Single-shot spinal anaesthesia (SSS) and combined spinal-epidural (CSE) anaesthesia are both commonly used for caesarean section anaesthesia. Spinals offer technical simplicity and rapid onset of nerve blockade which can be associated with hypotension. CSE anaesthesia allows for more gradual onset and also p...
journal_title:The Cochrane database of systematic reviews
pub_type: 杂志文章,评审
doi:10.1002/14651858.CD008100.pub2
更新日期:2019-10-11 00:00:00
abstract:BACKGROUND:Ulnar neuropathy at the elbow is the second most common entrapment neuropathy after carpal tunnel syndrome. Treatment may be conservative or surgical but optimal management remains controversial. This is an update of a review first published in 2010. OBJECTIVES:To determine the effectiveness and safety of c...
journal_title:The Cochrane database of systematic reviews
pub_type: 杂志文章,meta分析,评审
doi:10.1002/14651858.CD006839.pub3
更新日期:2012-07-11 00:00:00
abstract:BACKGROUND:Prostate cancer is a common cause of death in developed countries, yet the benefits of screening for prostate cancer still remain controversial. A prostate-specific antigen (PSA) test result greater than 4 ng/mL (nanograms/millilitre) has commonly been used as the cut-off level for seeking further tests to d...
journal_title:The Cochrane database of systematic reviews
pub_type: 杂志文章,meta分析,评审
doi:10.1002/14651858.CD008007.pub2
更新日期:2011-11-09 00:00:00
abstract:BACKGROUND:Demographic changes are leading to an increase in the number of older drivers: as dementia is an age-related disease, there is also an increase in the numbers of drivers with dementia. Dementia can impact on both the mobility and safety of drivers, and the impact of formal assessment of driving is unknown in...
journal_title:The Cochrane database of systematic reviews
pub_type: 杂志文章,评审
doi:10.1002/14651858.CD006222.pub2
更新日期:2009-01-21 00:00:00
abstract:BACKGROUND:This is an update of a Cochrane review first published in The Cochrane Library in Issue 1, 2006 and previously updated in 2009.Idiopathic sudden sensorineural hearing loss (ISSHL) is a clinical diagnosis characterised by a sudden deafness of cochlear or retrocochlear origin in the absence of a clear precipit...
journal_title:The Cochrane database of systematic reviews
pub_type: 杂志文章,meta分析,评审
doi:10.1002/14651858.CD003998.pub3
更新日期:2013-07-02 00:00:00
abstract:BACKGROUND:Clavicle fractures are common, accounting for 2.6% to 4% of all fractures. Eighty per cent of clavicle fractures are located in the middle third of the clavicle. Although treatment of these fractures is usually non-surgical, displaced clavicle fractures may be considered for surgical treatment because of the...
journal_title:The Cochrane database of systematic reviews
pub_type: 杂志文章,meta分析
doi:10.1002/14651858.CD009363.pub3
更新日期:2019-01-22 00:00:00
abstract:BACKGROUND:Routine use of caesarean section for breech presentation is widespread. However, poor outcomes after breech birth might be the result of underlying conditions causing breech presentation rather than damage during delivery. OBJECTIVES:The objective of this review was to assess the effects of planned caesarea...
journal_title:The Cochrane database of systematic reviews
pub_type: 杂志文章,评审
doi:10.1002/14651858.CD000166
更新日期:2001-01-01 00:00:00
abstract:BACKGROUND:Eye movement disorders may affect over 70% of stroke patients. These eye movement disorders can result in difficulty maintaining the normal ocular position and difficulty moving the eyes appropriately. The resulting functional disabilities include a loss of depth perception, reduced hand-to-eye co-ordination...
journal_title:The Cochrane database of systematic reviews
pub_type: 杂志文章,评审
doi:10.1002/14651858.CD008389.pub2
更新日期:2011-10-05 00:00:00
abstract:BACKGROUND:Nursing homes for older people provide an environment likely to promote the acquisition and spread of meticillin-resistant Staphylococcus aureus (MRSA), putting residents at increased risk of colonisation and infection. It is recognised that infection control strategies are important in preventing and contro...
journal_title:The Cochrane database of systematic reviews
pub_type: 杂志文章,评审
doi:10.1002/14651858.CD006354.pub2
更新日期:2008-01-23 00:00:00
abstract:BACKGROUND:Chronic Obstructive Pulmonary Disease (COPD) self-management interventions should be structured but personalised and often multi-component, with goals of motivating, engaging and supporting the patients to positively adapt their behaviour(s) and develop skills to better manage disease. Exacerbation action pl...
journal_title:The Cochrane database of systematic reviews
pub_type: 杂志文章,meta分析,评审
doi:10.1002/14651858.CD011682.pub2
更新日期:2017-08-04 00:00:00
abstract:BACKGROUND:Urinary incontinence has been shown to affect up to 50% of women. Studies in the USA have shown that up to 80% of these women have an element of stress urinary incontinence. This imposes significant health and economic burden on society and the women affected. Colposuspension and now mid-urethral slings have...
journal_title:The Cochrane database of systematic reviews
pub_type: 杂志文章,meta分析,评审
doi:10.1002/14651858.CD008709.pub3
更新日期:2017-07-26 00:00:00
abstract:BACKGROUND:Orthodontic relapse can be defined as the tendency for teeth to return to their pre-treatment position, and this occurs especially in lower front teeth (lower canines and lower incisors). Retention, to maintain the position of corrected teeth, has become one of the most important phases of orthodontic treatm...
journal_title:The Cochrane database of systematic reviews
pub_type: 杂志文章,评审
doi:10.1002/14651858.CD008734.pub2
更新日期:2013-09-06 00:00:00