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Psychological Medicine Jul 2017When used as an adjunctive with antipsychotics, certain vitamins and minerals may be effective for improving symptomatic outcomes of schizophrenia, by restoring... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
When used as an adjunctive with antipsychotics, certain vitamins and minerals may be effective for improving symptomatic outcomes of schizophrenia, by restoring nutritional deficits, reducing oxidative stress, or modulating neurological pathways.
METHOD
We conducted a systematic review of all randomized controlled trials (RCTs) reporting effects of vitamin and/or mineral supplements on psychiatric symptoms in people with schizophrenia. Random-effects meta-analyses were used to calculate the standardized mean difference between nutrient and placebo treatments.
RESULTS
An electronic database search in July 2016 identified 18 eligible RCTs, with outcome data for 832 patients. Pooled effects showed that vitamin B supplementation (including B6, B8 and B12) reduced psychiatric symptoms significantly more than control conditions [g = 0.508, 95% confidence interval (CI) 0.01-1.01, p = 0.047, I 2 = 72.3%]. Similar effects were observed among vitamin B RCTs which used intention-to-treat analyses (g = 0.734, 95% CI 0.00-1.49, p = 0.051). However, no effects of B vitamins were observed in individual domains of positive and negative symptoms (both p > 0.1). Meta-regression analyses showed that shorter illness duration was associated with greater vitamin B effectiveness (p = 0.001). There were no overall effects from antioxidant vitamins, inositol or dietary minerals on psychiatric symptoms.
CONCLUSIONS
There is preliminary evidence that certain vitamin and mineral supplements may reduce psychiatric symptoms in some people with schizophrenia. Further research is needed to examine how the benefits of supplementation relate to nutrient deficits and the impact upon underlying neurobiological pathways, in order to establish optimal nutrient formulations for improving clinical outcomes in this population. Future studies should also explore the effects of combining beneficial nutrients within multi-nutrient formulas.
Topics: Dietary Supplements; Humans; Schizophrenia; Vitamin B Complex
PubMed: 28202095
DOI: 10.1017/S0033291717000022 -
Critical Reviews in Food Science and... 2019The objective of this study was to quantify the association of B-vitamins intake with the future risk of coronary heart disease (CHD). A systematic search was performed... (Meta-Analysis)
Meta-Analysis
The objective of this study was to quantify the association of B-vitamins intake with the future risk of coronary heart disease (CHD). A systematic search was performed with the use of PubMed and Scopus from inception to April 30, 2018. Prospective cohort studies evaluating the association of intake of folate, vitamin B6, and vitamin B12 with risk of CHD in the general population were included. A random-effects meta-analysis was performed. Eleven prospective cohort studies (total = 369,746) with 5133 cases of CHD were included in the analyses. The relative risks were: 0.79 (95%CI: 0.69, 0.89; = 67%) for a 250 µg/d increment in folate intake; 0.87 (95%CI: 0.78, 0.96; = 80%) for a 0.5 mg/d increment in vitamin B6 intake; and 0.97 (95%CI: 0.80, 1.14: = 67%) for a 3 µg/d increment in vitamin B12 intake. The results did not change materially when the analyses were restricted only to dietary vitamins intake. A nonlinear dose-response meta-analysis demonstrated a linear inverse association between folate and vitamin B6 intake and risk of CHD. In conclusion, higher intake of folate and vitamin B6 is associated with a lower risk of CHD in the general population.
Topics: Cohort Studies; Coronary Disease; Diet; Dose-Response Relationship, Drug; Folic Acid; Humans; Vitamin B 12; Vitamin B 6
PubMed: 30431328
DOI: 10.1080/10408398.2018.1511967 -
Epilepsy & Behavior : E&B Mar 2023Levetiracetam (LVT), while an effective treatment for multiple seizure types, is associated with a high incidence of neuropsychiatric adverse events (NPAEs). In... (Review)
Review
BACKGROUND
Levetiracetam (LVT), while an effective treatment for multiple seizure types, is associated with a high incidence of neuropsychiatric adverse events (NPAEs). In predominantly retrospective studies, supplementation with pyridoxine/vitamin B (PN) was associated with improvement in NPAEs in some people. A previous review highlighted a lack of double-blind, controlled trials of PN for the treatment of NPAEs in individuals treated with LVT. The current paper updates the findings from the previous review to include evidence from studies published since June 2019.
METHODS
An updated systematic review of the published literature was performed in line with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. PubMed, Embase, the Cochrane Library, and Google Scholar were searched to identify studies published between June 2019 and 2nd November 2022 in which supplementary PN was initiated for the treatment of LVT-associated NPAEs. All study types were eligible. The risk of bias in randomized trials was assessed using the Cochrane risk-of-bias tool.
RESULTS
Seven additional studies were identified: two double-blind, randomized controlled trials (RCTs), four retrospective studies, and one retrospective case series. One RCT reported significant improvements from baseline in behavioral adverse events (BAEs) in both the intervention (PN) group and the low-dose control group (both p < 0.05), with a significantly greater improvement in the intervention group (p < 0.001). In the second RCT, differences in BAE severity between PN and placebo groups at the endpoint were not statistically significant. In one retrospective study, subjective irritability was reported to have improved from baseline in 9/20 individuals (45%) treated with supplementary PN. Data for systematic assessments (PHQ-9 and GAD-7) were available for 10 individuals. Assessment by PHQ-9 showed that six individuals improved, two worsened and two had no change. Based on the GAD-7, three people improved, two worsened and five had no change. In the second retrospective study, 18/41 individuals (44%) who commenced PN following the emergence of BAEs showed "significant" improvement. In a separate group of individuals with pre-existing behavioral problems in whom PN treatment was initiated at the same time as commencing LVT, 3/18 (16.7%) developed BAEs. This compared with 79/458 people (17.2%) who were initially treated only with LVT. The third retrospective study compared treatment-related irritability in individuals who had been treated with both LVT and perampanel, either sequentially or concomitantly. Two people who developed irritability while receiving LVT monotherapy were able to continue treatment with the addition of PN. The fourth study reported a significantly lower LVT discontinuation rate in individuals taking PN and a higher rate of improved behavior in those who were able to continue LVT. The case series reported improvements in behavioral symptoms in six people within two to three weeks of commencing supplementary PN.
CONCLUSION
Data published within the last three years add to earlier evidence suggesting that PN might be effective in the treatment of NPAEs associated with LVT. However, the quality of evidence remains poor and only a few prospective trials have been published. Data from placebo-controlled trials are still largely lacking. Currently, there is insufficient evidence to justify any firm recommendation for PN supplementation to treat NPAEs associated with LVT. Further well-designed, prospective trials are warranted.
Topics: Humans; Levetiracetam; Pyridoxine; Vitamin B 6; Treatment Outcome; Drug-Related Side Effects and Adverse Reactions; Randomized Controlled Trials as Topic
PubMed: 36791631
DOI: 10.1016/j.yebeh.2022.109065 -
International Journal of Molecular... May 2024The published data on the vitamin status of patients with phenylketonuria (PKU) is contradictory; therefore, this systematic review and meta-analysis evaluated the... (Meta-Analysis)
Meta-Analysis Review
The published data on the vitamin status of patients with phenylketonuria (PKU) is contradictory; therefore, this systematic review and meta-analysis evaluated the vitamin status of PKU patients. A comprehensive search of multiple databases (PubMed, Web of Sciences, Cochrane, and Scopus) was finished in March 2024. The included studies compared vitamin levels between individuals diagnosed with early-treated PKU and healthy controls while excluding pregnant and lactating women, untreated PKU or hyperphenylalaninemia cases, control groups receiving vitamin supplementation, PKU patients receiving tetrahydrobiopterin or pegvaliase, and conference abstracts. The risk of bias in the included studies was assessed by the Newcastle-Ottawa scale. The effect sizes were expressed as standardised mean differences. The calculation of effect sizes with 95% CI using fixed-effects models and random-effects models was performed. A -value < 0.05 was considered statistically significant. The study protocol was registered in the PROSPERO database (CRD42024519589). Out of the initially identified 11,086 articles, 24 met the criteria. The total number of participants comprised 770 individuals with PKU and 2387 healthy controls. The meta-analyses of cross-sectional and case-control studies were conducted for vitamin B12, D, A, E, B6 and folate levels. PKU patients demonstrated significantly higher folate levels (random-effects model, SMD: 1.378, 95% CI: 0.436, 2.320, = 0.004) and 1,25-dihydroxyvitamin D concentrations (random-effects model, SMD: 2.059, 95% CI: 0.250, 3.868, = 0.026) compared to the controls. There were no significant differences in vitamin A, E, B6, B12 or 25-dihydroxyvitamin D levels. The main limitations of the evidence include a limited number of studies and their heterogeneity and variability in patients' compliance. Our findings suggest that individuals with PKU under nutritional guidance can achieve a vitamin status comparable to that of healthy subjects. Our study provides valuable insights into the nutritional status of PKU patients, but further research is required to confirm these findings and explore additional factors influencing vitamin status in PKU.
Topics: Phenylketonurias; Humans; Vitamins; Vitamin D; Folic Acid; Vitamin B 12; Vitamin A
PubMed: 38791104
DOI: 10.3390/ijms25105065 -
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 -
Obesity Surgery Mar 2022Bariatric surgery, although an effective method, still has complications, like nutritional deficiencies. Our aim was to summarize the evidence on the frequency of... (Meta-Analysis)
Meta-Analysis Review
Bariatric surgery, although an effective method, still has complications, like nutritional deficiencies. Our aim was to summarize the evidence on the frequency of complex B vitamin deficiencies in studies comparing Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG). We included 25 studies for qualitative synthesis and 21 studies for quantitative synthesis. Relevant data was extracted, including proportion of patients with deficiency and mean serum vitamin values in 3 different timeframes. B12 and folate were the most prevalent deficiencies. B12 deficiency was more common after RYGB and folate serum mean levels were higher after RYGB. SG causes less nutrient deficiency and is therefore a better technique from this point of view. More studies are needed on B2, B3, and B6 vitamins to draw better conclusions.
Topics: Folic Acid; Gastrectomy; Gastric Bypass; Humans; Obesity, Morbid; Vitamin B Complex; Vitamin B Deficiency
PubMed: 34982396
DOI: 10.1007/s11695-021-05783-2 -
The American Journal of Clinical... Mar 2024The optimal dosage range for B-vitamin supplementation for stroke prevention has not received sufficient attention. (Meta-Analysis)
Meta-Analysis
BACKGROUND
The optimal dosage range for B-vitamin supplementation for stroke prevention has not received sufficient attention.
OBJECTIVE
Our aim was to determine the optimal dosage range of a combination of folic acid, vitamin B12, and vitamin B6 supplementation in stroke prevention.
METHODS
We searched PubMed, the Cochrane Central Register of Controlled Trials, and Embase database for randomized controlled trials published between January 1966 and April 2023, whose participants received B-vitamin supplementation and that reported the number of stroke cases. Relative risk (RR) was used to measure the effect of combined supplementation on risk of stroke using a fixed-effects model. Risk of bias was assessed with the Cochrane risk-of-bias algorithm.
RESULTS
The search identified 14 randomized controlled trials of folic acid combined with vitamin B12 and vitamin B6 supplementation for stroke prevention that included 76,664 participants with 2720 stroke cases. In areas without and with partial folic acid fortification, combined B-vitamin supplementation significantly reduced the risk of stroke by 34% [RR: 0.66; 95% confidence interval (CI): 0.50, 0.86] and 11% (RR: 0.89; 95% CI: 0.79, 1.00), respectively. Further analysis showed that a dosage of folic acid ≤0.8 mg/d and vitamin B12 ≤0.4 mg/d was best for stroke prevention (RR: 0.65; 95% CI: 0.48, 0.86) in these areas. In contrast, no benefit of combined supplementation was found in fortified areas (RR: 1.04; 95% CI: 0.94, 1.16).
CONCLUSIONS
Our meta-analysis found that the folic acid combined with vitamin B12 and vitamin B6 supplementation strategy significantly reduced the risk of stroke in areas without and with partial folic acid fortification. Combined dosages not exceeding 0.8 mg/d for folic acid and 0.4 mg/d for vitamin B12 supplementation may be more effective for populations within these areas. This trial was registered at PROSPERO asCRD42022355077.
Topics: Humans; Vitamins; Vitamin B 12; Folic Acid; Vitamin B 6; Stroke; Dietary Supplements
PubMed: 38432716
DOI: 10.1016/j.ajcnut.2023.12.021 -
BMJ Clinical Evidence May 2007Premenstrual symptoms occur in 95% of women of reproductive age. Severe, debilitating symptoms (PMS) occur in about 5% of those women. There is no consensus on how... (Review)
Review
INTRODUCTION
Premenstrual symptoms occur in 95% of women of reproductive age. Severe, debilitating symptoms (PMS) occur in about 5% of those women. There is no consensus on how symptom severity should be assessed, which has led to a wide variety of symptoms scales, making it difficult to synthesise data on treatment efficacy. The cyclical nature of the condition also makes it difficult to conduct RCTs.
METHODS AND OUTCOMES
We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of drug treatments; hormonal treatments; psychological interventions; physical therapies; dietary supplements; and surgical treatments in women with premenstrual syndrome? We searched: Medline, Embase, The Cochrane Library and other important databases up to November 2006 (Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).
RESULTS
We found 52 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.
CONCLUSIONS
In this systematic review we present information relating to the effectiveness and safety of the following interventions: acupuncture, alprazolam, bright light therapy, buspirone, chiropractic manipulation, clomipramine, cognitive behavioural therapy, danazol, endometrial ablation, evening primrose oil, exercise, gonadorelin analogues, hysterectomy, laparoscopic bilateral oophorectomy, magnesium supplements, metolazone, non-steroidal anti-inflammatory drugs, oestrogens, oral contraceptives, progesterone, progestogens, pyridoxine, reflexology, relaxation, selective serotonin reuptake inhibitors, spironolactone, tibolone.
Topics: Administration, Oral; Contraceptives, Oral; Dietary Carbohydrates; Dietary Supplements; Evidence-Based Medicine; Female; Humans; Life Style; Magnesium; Phytotherapy; Premenstrual Syndrome; Pyridoxine
PubMed: 19454075
DOI: No ID Found -
Movement Disorders Clinical Practice Feb 2019Clinical, neurophysiological, and pathological evidence suggest an association between Parkinson's disease (PD) and peripheral neuropathy (PNP), with a possible... (Review)
Review
BACKGROUND
Clinical, neurophysiological, and pathological evidence suggest an association between Parkinson's disease (PD) and peripheral neuropathy (PNP), with a possible causative role of levodopa metabolic products, such as homocysteine and methylmalonic acid.
METHODS
We conducted a systematic review of studies reporting cases of PNP in l-dopa-treated PD patients indexed in PubMed between January 1990 and March 2018.
RESULTS
We identified 38 articles reporting cases of PNP in PD patients treated with oral l-dopa or with l-dopa/carbidopa intestinal gel infusion (LCIG). Prevalence of PNP was 30.2% in the former group and 42.1% in the latter. Oral l-dopa was mostly associated with slowly progressive PNP, whereas LCIG showed an acute or subacute onset in 35.7% of cases. In both groups, there was an association between PNP and higher l-dopa doses, as well as with the following biochemical alterations: increased homocysteine; reduced vitamin B12; increased methylmalonic acid; and reduced vitamin B6. A skin biopsy was performed in 181 patients, showing signs of small fibers neuropathy in 169 (93.4%). Positive, yet preliminary, results were observed in patients receiving periodic vitamin supplementation.
CONCLUSIONS
Over one third of PD patients in treatment with l-dopa may develop PNP, with a significantly higher prevalence of acute and subacute forms in those receiving LCIG. Pathogenic mechanisms remain unclear, but possibly related to a complex interplay between peripheral neurodegenerative processes and l-dopa neurotoxic metabolites. Prospective, randomized, clinical trials are required to identify factors associated with the onset and progression of PD-associated PNP and clarify the protective role of B-group vitamin supplementation.
PubMed: 30838307
DOI: 10.1002/mdc3.12688 -
Nutrition and Cancer 2023Inconsistent findings have emerged from epidemiological research investigating the association between vitamin B and the risk of gastric cancer. To obtain a more precise... (Meta-Analysis)
Meta-Analysis Review
Inconsistent findings have emerged from epidemiological research investigating the association between vitamin B and the risk of gastric cancer. To obtain a more precise assessment, we conducted a comprehensive search of published data and performed a meta-analysis. PubMed, Web of Science, EMBASE and Cochrane Library databases were systematically searched. A total of 12 studies (5 prospective cohort and 7 case-control studies) involving 5,692 cases and 814,157 participants were included in the meta-analysis. The results showed that high intake of vitamin B may reduce the odds of gastric cancer (OR = 0.83, 95% CI: 0.73-0.95, = 0.006). However, this association was only observed in the case-control studies (OR = 0.68, 95% CI: 0.51-0.89, = 0.006) but not in the cohort studies (RR = 1.01, 95% CI: 0.94-1.08, = 0.819). Additionally, the negative association between vitamin B intake and gastric cancer risk was found in the United States of America (OR = 0.71, 95% CI: 0.62-0.82, = 10), but not in Europe (OR = 0.88, 95% CI: 0.74-1.05, = 0.169) or the other regions (OR = 0.86, 95% CI: 0.66-1.13, = 0.280). In conclusion, there is not sufficient evidence to assume that vitamin B intake is associated with gastric cancer risk, which needs further confirmation.
Topics: Humans; United States; Vitamin B 6; Stomach Neoplasms; Prospective Studies; Risk; Vitamins; Vitamin B 12
PubMed: 37904520
DOI: 10.1080/01635581.2023.2274134