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Clinical Epidemiology 2018Various interventions have been tested as primary prevention of colorectal cancers (CRC), but comprehensive evidence comparing them is absent. We examined the effects of...
BACKGROUND
Various interventions have been tested as primary prevention of colorectal cancers (CRC), but comprehensive evidence comparing them is absent. We examined the effects of various chemopreventive agents (CPAs) on CRC incidence and mortality.
METHODS
We did a network meta-analysis based on a systematic review of randomized controlled trials (RCTs) that compared at least one CPA (aspirin, antioxidants, folic acid, vitamin B6, vitamin B12, calcium, vitamin D, alone or in combination) to placebo or other CPA in persons without history of CRC. Several databases were searched from inception up to March 2017. Primary outcomes were early and long-term CRC incidence and mortality.
RESULTS
Twenty-one RCTs comprising 281,063 participants, 9 RCTS comprising 160,101 participants, and 7 RCTs comprising 24,001 participants were included in the network meta-analysis for early risk of CRC incidence, long-term risk of CRC incidence and mortality, respectively. For early CRC incidence, no CPAs were found to be effective. For long-term CRC incidence and mortality, aspirin was the only intervention that showed protective effects with potential dose-dependent effects (risk ratio [RR], 0.74 [95% CI, 0.57-0.97] for high-dose [≥325 mg/day] and RR, 0.81 [95% CI, 0.67-0.98] for very-low-dose [≤100 mg/day]). Similar trend was found for mortality (RR, 0.43 [95% CI, 0.23-0.81] for low-dose [>100-325 mg/day] and RR, 0.65 [95% CI, 0.45-0.94] for very-low-dose). However, in net clinical benefit analysis, when combining risk estimates on mortality from CRC, cardiovascular disease, and pooled risk estimates of major gastrointestinal bleeding, low-dose aspirin provided the highest net survival gain (%) of 1.736 [95% CI, 1.010-2.434].
CONCLUSION
Aspirin at the dose range of 75-325 mg/day is a safe and effective primary prevention for long-term CRC among people at average risk. None of the other CPAs were found to be effective. There may potentially be differential effects among various doses of aspirin that needs further investigation.
PubMed: 30349391
DOI: 10.2147/CLEP.S174120 -
The Journal of Nervous and Mental... Feb 2018Patients with psychotic disorders regularly use natural medicines, although it is unclear whether these are effective and safe. The aim of this study was to provide an...
Patients with psychotic disorders regularly use natural medicines, although it is unclear whether these are effective and safe. The aim of this study was to provide an overview of evidence for improved outcomes by natural medicines. A systematic literature search was performed through Medline, PsycINFO, CINAHL, and Cochrane until May 2015. In 110 randomized controlled trials, evidence was found for glycine, sarcosine, N-acetylcysteine, some Chinese and ayurvedic herbs, ginkgo biloba, estradiol, and vitamin B6 to improve psychotic symptoms when added to antipsychotics. Ginkgo biloba and vitamin B6 seemed to reduce tardive dyskinesia and akathisia. Results on other compounds were negative or inconclusive. All natural agents, except reserpine, were well tolerated. Most study samples were small, study periods were generally short, and most results need replication. However, there is some evidence for beneficial effects of certain natural medicines.
Topics: Antipsychotic Agents; Complementary Therapies; Ginkgo biloba; Humans; Medicine, Ayurvedic; Medicine, Chinese Traditional; Phytotherapy; Plant Extracts; Psychotic Disorders; Treatment Outcome
PubMed: 29373456
DOI: 10.1097/NMD.0000000000000782 -
Shokuhin Eiseigaku Zasshi. Journal of... 2017The interaction of levodopa and vitamin B6 is a well-known issue. This study investigated the incidence of unacceptable intake levels of vitamin B6 among levodopa users... (Meta-Analysis)
Meta-Analysis
The interaction of levodopa and vitamin B6 is a well-known issue. This study investigated the incidence of unacceptable intake levels of vitamin B6 among levodopa users by means of a systematic review. We searched two databases (PubMed and "Igaku Chuo Zasshi") for articles about adverse events due to the interaction of levodopa and vitamin B6 published up to August 2017. Of 98 citations retrieved, 11 studies met the selection criteria. The results indicated that a vitamin B6 intake level of more than 50 mg/day could reduce the efficacy of levodopa. The recommended intake of vitamin B6 for Japanese adults is 1.4 mg/day for men and 1.2 mg/day for women. Therefore, the acceptable intake of vitamin B6 for levodopa patients would be within the range of the recommended intake level, which is also within the usual range in foods in Japan, except for dietary supplements or health foods. Levodopa users should be cautious about taking dietary supplements and over-the-counter drugs.
Topics: Databases, Bibliographic; Dietary Supplements; Drug Interactions; Female; Humans; Levodopa; Male; No-Observed-Adverse-Effect Level; Nonprescription Drugs; Parkinson Disease; Vitamin B 6
PubMed: 29311446
DOI: 10.3358/shokueishi.58.268 -
Urology Journal Dec 2017This review systematically discusses and summarizes the effect of vitamin B6 on semen quality.
PURPOSE
This review systematically discusses and summarizes the effect of vitamin B6 on semen quality.
MATERIAL AND METHOD
To achieve this contribution, we searched the PubMed, Scopus, and Web of Science databases for English language papers from 1984 through 2017 using the key words "sperm" versus "Vitamin B6", "pyridoxine", and "pyridoxal". Also, the references from selected published papers were included, only if relevant.
RESULT
To date, as revealed by rodent studies, high doses of vitamin B6 impair semen quality and sperm parameters. While in humans, it is suggested, but not yet directly approved, that seminal vitamin B6 levels may alter sperm quality (i.e., sperm quantity and quality), and that vitamin B6 deficiency may trigger the chemical toxicity to sperm (i.e., hyperhomocysteinemia, oxidative injury).
CONCLUSION
The adverse effect of vitamin B6, when used at high doses, has been revealed in experimental animals, but not yet directly approved in humans. Consequently, in vitro studies on human ejaculate as well as clinical studies that investigate the direct effect of vitamin B6 on semen quality seem very significant.
PubMed: 29290084
DOI: 10.22037/uj.v0i0.3808 -
The Cochrane Database of Systematic... Aug 2017Cardiovascular disease, which includes coronary artery disease, stroke and peripheral vascular disease, is a leading cause of death worldwide. Homocysteine is an amino... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Cardiovascular disease, which includes coronary artery disease, stroke and peripheral vascular disease, is a leading cause of death worldwide. Homocysteine is an amino acid with biological functions in methionine metabolism. A postulated risk factor for cardiovascular disease is an elevated circulating total homocysteine level. The impact of homocysteine-lowering interventions, given to patients in the form of vitamins B6, B9 or B12 supplements, on cardiovascular events has been investigated. This is an update of a review previously published in 2009, 2013, and 2015.
OBJECTIVES
To determine whether homocysteine-lowering interventions, provided to patients with and without pre-existing cardiovascular disease are effective in preventing cardiovascular events, as well as reducing all-cause mortality, and to evaluate their safety.
SEARCH METHODS
We searched the Cochrane Central Register of Controlled Trials (CENTRAL 2017, Issue 5), MEDLINE (1946 to 1 June 2017), Embase (1980 to 2017 week 22) and LILACS (1986 to 1 June 2017). We also searched Web of Science (1970 to 1 June 2017). We handsearched the reference lists of included papers. We also contacted researchers in the field. There was no language restriction in the search.
SELECTION CRITERIA
We included randomised controlled trials assessing the effects of homocysteine-lowering interventions for preventing cardiovascular events with a follow-up period of one year or longer. We considered myocardial infarction and stroke as the primary outcomes. We excluded studies in patients with end-stage renal disease.
DATA COLLECTION AND ANALYSIS
We performed study selection, 'Risk of bias' assessment and data extraction in duplicate. We estimated risk ratios (RR) for dichotomous outcomes. We calculated the number needed to treat for an additional beneficial outcome (NNTB). We measured statistical heterogeneity using the I statistic. We used a random-effects model. We conducted trial sequential analyses, Bayes factor, and fragility indices where appropriate.
MAIN RESULTS
In this third update, we identified three new randomised controlled trials, for a total of 15 randomised controlled trials involving 71,422 participants. Nine trials (60%) had low risk of bias, length of follow-up ranged from one to 7.3 years. Compared with placebo, there were no differences in effects of homocysteine-lowering interventions on myocardial infarction (homocysteine-lowering = 7.1% versus placebo = 6.0%; RR 1.02, 95% confidence interval (CI) 0.95 to 1.10, I = 0%, 12 trials; N = 46,699; Bayes factor 1.04, high-quality evidence), death from any cause (homocysteine-lowering = 11.7% versus placebo = 12.3%, RR 1.01, 95% CI 0.96 to 1.06, I = 0%, 11 trials, N = 44,817; Bayes factor = 1.05, high-quality evidence), or serious adverse events (homocysteine-lowering = 8.3% versus comparator = 8.5%, RR 1.07, 95% CI 1.00 to 1.14, I = 0%, eight trials, N = 35,788; high-quality evidence). Compared with placebo, homocysteine-lowering interventions were associated with reduced stroke outcome (homocysteine-lowering = 4.3% versus comparator = 5.1%, RR 0.90, 95% CI 0.82 to 0.99, I = 8%, 10 trials, N = 44,224; high-quality evidence). Compared with low doses, there were uncertain effects of high doses of homocysteine-lowering interventions on stroke (high = 10.8% versus low = 11.2%, RR 0.90, 95% CI 0.66 to 1.22, I = 72%, two trials, N = 3929; very low-quality evidence).We found no evidence of publication bias.
AUTHORS' CONCLUSIONS
In this third update of the Cochrane review, there were no differences in effects of homocysteine-lowering interventions in the form of supplements of vitamins B6, B9 or B12 given alone or in combination comparing with placebo on myocardial infarction, death from any cause or adverse events. In terms of stroke, this review found a small difference in effect favouring to homocysteine-lowering interventions in the form of supplements of vitamins B6, B9 or B12 given alone or in combination comparing with placebo.There were uncertain effects of enalapril plus folic acid compared with enalapril on stroke; approximately 143 (95% CI 85 to 428) people would need to be treated for 5.4 years to prevent 1 stroke, this evidence emerged from one mega-trial.Trial sequential analyses showed that additional trials are unlikely to increase the certainty about the findings of this issue regarding homocysteine-lowering interventions versus placebo. There is a need for additional trials comparing homocysteine-lowering interventions combined with antihypertensive medication versus antihypertensive medication, and homocysteine-lowering interventions at high doses versus homocysteine-lowering interventions at low doses. Potential trials should be large and co-operative.
Topics: Angina Pectoris; Cardiovascular Diseases; Cause of Death; Folic Acid; Humans; Hyperhomocysteinemia; Myocardial Infarction; Randomized Controlled Trials as Topic; Risk Factors; Stroke; Vitamin B 12; Vitamin B 6; Vitamin B Complex
PubMed: 28816346
DOI: 10.1002/14651858.CD006612.pub5 -
Nutrients Jun 2017Although vitamins play a major role in health, and their deficiency may be linked to symptoms of optic-nerve dysfunction, the association between serum vitamin levels... (Meta-Analysis)
Meta-Analysis Review
Although vitamins play a major role in health, and their deficiency may be linked to symptoms of optic-nerve dysfunction, the association between serum vitamin levels and glaucoma in humans remains controversial. In this study, articles in the PubMed, Web of Science, and EMBASE databases were searched up to 25March 2017. Nine studies on primary open-angle glaucoma (POAG), four studies on normal tension glaucoma (NTG), and six studies on exfoliative glaucoma (EXG) were retrieved. The combined results showed no differences in the levels of serum vitamin B₆ between POAG ( = 0.406) and EXG ( = 0.139) patients and controls. The weighted mean differences (WMDs) with 95% confidence intervals (CIs) were 2.792 ng/mL (-3.793 to 9.377) and 1.342 ng/mL (-3.120 to 0.436), respectively. There was no difference between POAG ( = 0.952), NTG ( = 0.757), or EXG ( = 0.064) patients and controls in terms of serum vitamin B. The WMDs with 95% CIs were 0.933 pg/mL (-31.116 to 29.249), 6.652 pg/mL (-35.473 to 48.777), and 49.946 pg/mL (-102.892 to 3.001), respectively. The serum vitamin D levels exhibited no differences ( = 0.064) between POAG patients and controls; the WMD with 95% CI was 2.488 ng/mL (-5.120 to 0.145). In conclusion, there was no association found between serum vitamin B₆, vitamin B, or vitamin D levels and the different types of glaucoma.
Topics: Glaucoma; Glaucoma, Open-Angle; Humans; Sensitivity and Specificity; Vitamin B 12; Vitamin B 6; Vitamin D
PubMed: 28635642
DOI: 10.3390/nu9060636 -
International Journal For Equity in... May 2017A significant proportion of homeless people drink alcohol excessively and this can lead to malnutrition and consequent medical problems. The aim of this review was to... (Review)
Review
BACKGROUND
A significant proportion of homeless people drink alcohol excessively and this can lead to malnutrition and consequent medical problems. The aim of this review was to assess the evidence on the range of nutritional deficiencies in the homeless problem-drinking populations.
METHODS
We conducted a comprehensive search of nine scientific literature databases and 13 grey literature sources. We included studies of any design that included homeless population with problem-drinking and reported measures of nutritional deficiencies in urine or blood. Study selection and data extraction was done by one reviewer and checked by another. Data on malnutrition profile were summarized narratively.
RESULTS
We found nine studies reporting nutritional deficiencies in homeless populations with problem-drinking. The oldest study was from the 1950s and the most recent from 2013. The following nutrients were reported across studies: vitamins B1, B2, B6, B9, B12, C, A, and E; haemoglobin; and albumin. The most common deficiencies reported were of vitamin B1 (prevalence of deficiency was 0, 2, 6, 45, and 51% in five studies) and vitamin C (29, 84, and 95% in three studies). None of the studies were assessed to be at a low risk of bias.
CONCLUSIONS
The limited, low quality and relatively old evidence suggests that homeless people who drink heavily may be deficient in vitamin C, thiamine, and other nutrients. New, well conducted studies are needed in order to optimally inform public health interventions aimed at improving deficiencies in this population.
TRIAL REGISTRATION
PROSPERO CRD42015024247.
Topics: Adult; Aged; Aged, 80 and over; Alcohol Drinking; Female; Health Status; Ill-Housed Persons; Humans; Male; Malnutrition; Middle Aged; Prevalence
PubMed: 28476156
DOI: 10.1186/s12939-017-0564-4 -
The Journal of Nutrition, Health & Aging 2017The aim of our scoping review was to summarize the state of the art regarding micronutrients in order to identify which of them might effectively improve health status... (Review)
Review
OBJECTIVE
The aim of our scoping review was to summarize the state of the art regarding micronutrients in order to identify which of them might effectively improve health status in the areas typically impaired in older people: bone, skeletal muscle, and cognitive function.
DESIGN
Scoping review.
METHODS
The Italian Study Group on Healthy Aging by Nutraceuticals and Dietary Supplements (HANDS) performed this scoping review, based on the following steps: doing a list of micronutrients related with musculoskeletal or cognitive functions, included in dietary supplements and nutraceuticals commercialized in Italy; planning a research on PubMed, according to an evidence-based approach, in order to the most relevant positive study for each micronutrient into each of the three areas involved (bone, skeletal muscle and cognitive function); identifying the micronutrients effective in maintaining or achieving an adequate health status in older people, specifying the effective and safe daily doses, according to the selected studies.
RESULTS
In literature we found 12 relevant positive studies (1 international society guidelines/recommendations, 1 systematic review, 7 randomized controlled trials, and 3 prospective cohort studies). We showed that only 16 micronutrients resulted to have appropriate scientific evidences in terms of improving musculoskeletal health and/or cognitive function in older people: beta-alanine, calcium, creatine, fluorides, leucine, magnesium, omega-3 fatty acids, potassium, vitamin B6, vitamin B9, vitamin B12, vitamin C, vitamin D, vitamin E, vitamin K2, and zinc.
CONCLUSION
This scoping review showed that selected micronutrients in adequate doses might have an ancillary role in musculoskeletal health and cognitive functions in older people.
Topics: Aged; Amino Acids; Bone and Bones; Calcium, Dietary; Cognition; Cognition Disorders; Dietary Supplements; Fatty Acids, Omega-3; Fluorides; Humans; Italy; Magnesium; Micronutrients; Muscle, Skeletal; Musculoskeletal Diseases; Potassium; Vitamin B Complex; Vitamin D; Zinc
PubMed: 28448083
DOI: 10.1007/s12603-016-0823-x -
Journal of Inherited Metabolic Disease Jan 2017Cystathionine beta-synthase (CBS) deficiency is a rare inherited disorder in the methionine catabolic pathway, in which the impaired synthesis of cystathionine leads to... (Review)
Review
Cystathionine beta-synthase (CBS) deficiency is a rare inherited disorder in the methionine catabolic pathway, in which the impaired synthesis of cystathionine leads to accumulation of homocysteine. Patients can present to many different specialists and diagnosis is often delayed. Severely affected patients usually present in childhood with ectopia lentis, learning difficulties and skeletal abnormalities. These patients generally require treatment with a low-methionine diet and/or betaine. In contrast, mildly affected patients are likely to present as adults with thromboembolism and to respond to treatment with pyridoxine. In this article, we present recommendations for the diagnosis and management of CBS deficiency, based on a systematic review of the literature. Unfortunately, the quality of the evidence is poor, as it often is for rare diseases. We strongly recommend measuring the plasma total homocysteine concentrations in any patient whose clinical features suggest the diagnosis. Our recommendations may help to standardise testing for pyridoxine responsiveness. Current evidence suggests that patients are unlikely to develop complications if the plasma total homocysteine concentration is maintained below 120 μmol/L. Nevertheless, we recommend keeping the concentration below 100 μmol/L because levels fluctuate and the complications associated with high levels are so serious.
Topics: Betaine; Cystathionine beta-Synthase; Homocysteine; Homocystinuria; Humans; Methionine; Pyridoxine
PubMed: 27778219
DOI: 10.1007/s10545-016-9979-0 -
PloS One 2016In many countries breakfast cereals are an important component of breakfast. This systematic review assesses the contribution of consumption of ready-to eat cereal... (Review)
Review
BACKGROUND
In many countries breakfast cereals are an important component of breakfast. This systematic review assesses the contribution of consumption of ready-to eat cereal (RTEC) to the recommended nutrient intake. Furthermore, the effects of RTEC consumption on key health parameters are investigated as well as health promoting properties of RTEC.
METHOD
The Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE and CINAHL have been searched up till 16th of June 2015. Randomized controlled trials were excluded if RTEC were used during hypocaloric diets, if RTEC were eaten at other times than breakfast and if breakfasts included other products than RTEC, milk and fruit. Observational studies were excluded when "breakfast cereals" were not defined or their definition included cooked cereals. From cross-sectional studies only data concerning energy and nutrient intake as well as micronutrient status were used.
RESULTS
From 4727 identified citations 64 publications met the inclusion criteria of which 32 were cross-sectional studies, eight prospective studies and 24 randomized controlled trials. Consumption of RTEC is associated with a healthier dietary pattern, concerning intake of carbohydrates, dietary fiber, fat and micronutrients, however total sugar intake is higher. Persons consuming RTEC frequently (≥ 5 times/week) have a lower risk of inadequate micronutrient intake especially for vitamin A, calcium, folate, vitamin B 6, magnesium and zinc. Evidence from prospective studies suggests that whole grain RTEC may have beneficial effects on hypertension and type 2 diabetes. Consumption of RTEC with soluble fiber helps to reduce LDL cholesterol in hypercholesterolemic men and RTEC fortified with folate can reduce plasma homocysteine.
DISCUSSION
One of the review's strengths is its thorough ex/inclusion of studies. Limitations are that results of observational studies were based on self-reported data and that many studies were funded by food-industry.
CONCLUSION
Consumption of RTEC, especially of fiber-rich or whole grain RTEC, is implicated with several beneficial nutritional and health outcomes. The effect on body weight, intestinal health and cognitive function needs further evaluation. Of concern is the higher total sugar intake associated with frequent RTEC consumption.
Topics: Cardiovascular Diseases; Cognition; Databases, Factual; Diabetes Mellitus, Type 2; Edible Grain; Energy Intake; Humans; Micronutrients; Nutritive Value
PubMed: 27749919
DOI: 10.1371/journal.pone.0164931