-
Journal of Thrombosis and Thrombolysis Nov 2012A homocysteine-independent role for B-group vitamins on venous thrombosis (VT) development has been reported. However, related research findings remain inconsistent.... (Meta-Analysis)
Meta-Analysis Review
A homocysteine-independent role for B-group vitamins on venous thrombosis (VT) development has been reported. However, related research findings remain inconsistent. PUBMED, EMBASE, and COCHRANE databases were searched to collect information on all eligible studies to make a meta-analysis about the relationship between B-group vitamins and VT. Literature search results did not suggest a correlation between thiamin, pantothenic acid, niacin, or riboflavin with VT. Based on their correlations in the literature, folic acid, vitamin B12, B6 were considered in the meta-analysis and systematic review. Significant standardized mean differences were obtained for plasma folic acid (-0.55; 95% CI, -0.75 to -0.36) and vitamin B12 (-0.34; 95% CI, -0.55 to -0.13). Reduced levels of folic acid and vitamin B12 may be independent risk factors of VT. Moreover, a qualitative systematic review indicated that low level of vitamin B6 was an independent risk factor of VT. Randomized clinical studies of B-group vitamins supplementation showed varying results on VT prevention. Multivitamin supplementation for VT prevention, regardless of homocysteine level, would be of interest. Further prospective clinical studies are needed to provide additional evidence on the clinical benefits of B-group vitamin supplementation for VT.
Topics: Female; Homocysteine; Humans; Male; PubMed; Randomized Controlled Trials as Topic; Risk Factors; Venous Thrombosis; Vitamin B Complex
PubMed: 22743781
DOI: 10.1007/s11239-012-0759-x -
The Cochrane Database of Systematic... Apr 2010Protein Energy Malnutrition is an important cause of child morbidity and mortality in middle- and low-income countries. It has been suggested that excessive free radical... (Review)
Review
BACKGROUND
Protein Energy Malnutrition is an important cause of child morbidity and mortality in middle- and low-income countries. It has been suggested that excessive free radical activity may be responsible for the clinical manifestation of kwashiorkor. Antioxidants may be able to curb excessive free radical activity and prevent the development of kwashiorkor in susceptible children.
OBJECTIVES
To evaluate the benefits of supplementation of vitamin E, selenium, cysteine and riboflavin (alone or in combination) in preventing kwashiorkor.
SEARCH STRATEGY
We conducted searches of CENTRAL 2009 (The Cochrane Library 2009 Issue 2), MEDLINE 1966 to 2009, EMBASE 1980 to 2009, CINAHL 1982 to 2009, LILACS 1982 to 2009, Meta register of Controlled trials, Open Sigle, African Index Medicus.
SELECTION CRITERIA
Randomised controlled trials (RCTs) and quasi-RCTs evaluating vitamin E, selenium, cysteine and riboflavin alone or in combination in healthy pre-school children in middle- and low-income countries.
DATA COLLECTION AND ANALYSIS
Two authors extracted and independently analysed data.
MAIN RESULTS
One cluster-RCT including 2372 children met our inclusion criteria. Children were randomised, based on household, either to a supplement containing all four micronutrients or to placebo. No statistically significant difference in the incidence of kwashiorkor between the intervention and control groups could be demonstrated at 20 weeks (RR 1.70; 95% CI 0.98 to 2.42). Nor could any statistically significant difference in all-cause mortality be demonstrated (RR 0.75; 95% CI 0.17 to 3.36).
AUTHORS' CONCLUSIONS
Based on the one available trial, we could draw no firm conclusion for the effectiveness of supplementary antioxidant micronutrients for the prevention of kwashiorkor in pre-school children.
Topics: Antioxidants; Child, Preschool; Cysteine; Humans; Infant; Kwashiorkor; Micronutrients; Riboflavin; Selenium; Vitamin E
PubMed: 20393967
DOI: 10.1002/14651858.CD008147.pub2 -
Nutrition Reviews Feb 2022The results from epidemiologic studies on the intake of dietary vitamin B1, B2, B6, and B12 and association with risk of developing depression have been inconsistent. (Meta-Analysis)
Meta-Analysis
CONTEXT
The results from epidemiologic studies on the intake of dietary vitamin B1, B2, B6, and B12 and association with risk of developing depression have been inconsistent.
OBJECTIVE
The purpose of this systematic review and meta-analysis was to summarize the existing evidence and synthesize the results.
DATA SOURCES
The databases of Web of Science and PubMed were searched for relevant articles published in English until September 2020.
STUDY SELECTION
Observational studies that evaluated the associations between depression and dietary vitamin B1, B2, B6, and B12 were included in this study.
DATA EXTRACTION
The job of data extraction was undertaken by 2 authors, and the pooled relative risks (RRs) and 95% confidence intervals (CIs) were calculated using a fixed-effects model.
RESULTS
Thirteen articles related to 18 studies were eligible for inclusion in this systematic review and meta-analysis. The pooled RR (95% CI) of depression for the highest vs the lowest category of dietary vitamin B1, B2, B6, and B12 was 0.69 (0.55-0.87), 0.77 (0.67-0.89), 0.81 (0.71-0.93), and 0.86 (0.75-0.99), respectively. The pooled RR (95% CI) of depression for the highest vs the lowest category of dietary vitamin B2 was 0.80 (0.64-0.99) in females and 0.83 (0.67-1.02) in males, for dietary vitamin B6 was 0.71 (0.59-0.86) in females and 0.92 (0.76-1.12) in males, and for dietary vitamin B12 was 0.79 (0.65-0.97) in females and 0.94 (0.77-1.15) in males.
CONCLUSION
This study suggested that the intake of dietary vitamin B1, B2, B6, and B12 may be inversely associated with the risk of depression; the inverse associations observed between depression and intake of dietary vitamin B2, B6, and B12 were significant in females, but not in males. Further studies are needed to confirm these results.
Topics: Depression; Female; Folic Acid; Humans; Male; Observational Studies as Topic; Riboflavin; Thiamine; Vitamin B 12; Vitamin B 6
PubMed: 33912967
DOI: 10.1093/nutrit/nuab014 -
Journal of Cataract and Refractive... May 2024Corneal crosslinking (CXL) is used for treating keratoconus and post-laser in situ keratomileusis ectasia. However, refractive surgery is not usually performed with... (Meta-Analysis)
Meta-Analysis Comparative Study
Corneal crosslinking (CXL) is used for treating keratoconus and post-laser in situ keratomileusis ectasia. However, refractive surgery is not usually performed with prophylactic CXL. Therefore, we performed a meta-analysis comparing outcomes of refractive surgeries with vs without prophylactic CXL. We systematically searched databases for studies comparing refractive surgeries for myopic correction with vs without prophylactic corneal crosslinking. Review Manager 5.4.1 was used to perform statistical analysis. We included 2820 eyes from 28 studies. Compared with refractive surgery alone, surgery with prophylactic CXL resulted in decreased central corneal thickness, corrected distance visual acuity logMAR, and safety and efficacy indices. There were no significant differences in postoperative uncorrected distance visual acuity of 20/20 or better at ≥12 months and other visual outcomes among both groups. More randomized controlled trials with standard crosslinking protocols are needed to analyze the prophylactic use of crosslinking with refractive surgeries.
Topics: Humans; Cross-Linking Reagents; Photosensitizing Agents; Keratomileusis, Laser In Situ; Riboflavin; Collagen; Visual Acuity; Myopia; Photorefractive Keratectomy; Photochemotherapy; Lasers, Excimer; Corneal Stroma; Ultraviolet Rays; Keratoconus; Corneal Surgery, Laser; Refraction, Ocular
PubMed: 38288954
DOI: 10.1097/j.jcrs.0000000000001405 -
Cells Aug 2022This study aimed to identify the role of crosslinking agents in the resin-dentin bond strength (BS) when used as modifiers in adhesives or pretreatments to the dentin... (Meta-Analysis)
Meta-Analysis Review
This study aimed to identify the role of crosslinking agents in the resin-dentin bond strength (BS) when used as modifiers in adhesives or pretreatments to the dentin surface through a systematic review and meta-analysis. This paper was conducted according to the directions of the PRISMA 2020 statement. The research question of this review was: "Would the use of crosslinkers agents improve the BS of resin-based materials to dentin?" The literature search was conducted in the following databases: Embase, PubMed, Scielo, Scopus, and Web of Science. Manuscripts that reported the effect on the BS after the use of crosslinking agents were included. The meta-analyses were performed using Review Manager v5.4.1. The comparisons were performed by comparing the standardized mean difference between the BS values obtained using the crosslinker agent or the control group. The subgroup comparisons were performed based on the adhesive strategy used (total-etch or self-etch). The immediate and long-term data were analyzed separately. A total of 50 articles were included in the qualitative analysis, while 45 articles were considered for the quantitative analysis. The meta-analysis suggested that pretreatment with epigallocatechin-3-gallate (EGCG), carbodiimide, ethylenediaminetetraacetic acid (EDTA), glutaraldehyde, and riboflavin crosslinking agents improved the long-term BS of resin composites to dentin ( ≤ 0.02). On the other hand, the use of proanthocyanidins as a pretreatment improved both the immediate and long-term BS values ( ≤ 0.02). When incorporated within the adhesive formulation, only glutaraldehyde, riboflavin, and EGCG improved the long-term BS to dentin. It could be concluded that the application of different crosslinking agents such as carbodiimide, EDTA, glutaraldehyde, riboflavin, and EGCG improved the long-term BS of adhesive systems to dentin. This effect was observed when these crosslinkers were used as a separate step and when incorporated within the formulation of the adhesive system.
Topics: Adhesives; Carbodiimides; Collagen; Dentin; Dentin-Bonding Agents; Edetic Acid; Glutaral; Materials Testing; Resin Cements; Riboflavin
PubMed: 35954261
DOI: 10.3390/cells11152417 -
Nutritional Neuroscience Dec 2023Brain oxygen deprivation causes morphological damage involved in the formation of serious pathological conditions such as stroke and cerebral palsy. Therapeutic methods... (Review)
Review
Brain oxygen deprivation causes morphological damage involved in the formation of serious pathological conditions such as stroke and cerebral palsy. Therapeutic methods for post-hypoxia/anoxia injuries are limited and still have deficiencies in terms of safety and efficacy. Recently, clinical studies of stroke have reported the use of drugs containing riboflavin for post-injury clinical rehabilitation, however, the effects of vitamin B2 on exposure to cerebral oxygen deprivation are not completely elucidated. This review aimed to investigate the potential antioxidant, anti-inflammatory and neuroprotective effects of riboflavin in cerebral hypoxia/anoxia. After a systematic search, 21 articles were selected, 8 preclinical and 12 clinical studies, and 1 translational study. Most preclinical studies used B2 alone in models of hypoxia in rodents, with doses of 1-20 mg/kg (in vivo) and 0.5-5 µM (in vitro). Together, these works suggested greater regulation of lipid peroxidation and apoptosis and an increase in neurotrophins, locomotion, and cognition after treatment. In contrast, several human studies have administered riboflavin (5 mg) in combination with other Krebs cycle metabolites, except one study, which used only B2 (20 mg). A reduction in lactic acidosis and recovery of sensorimotor functions was observed in children after treatment with B2, while adults and the elderly showed a reduction in infarct volume and cognitive rehabilitation. Based on findings from preclinical and clinical studies, we conclude that the use of riboflavin alone or in combination acts beneficially in correcting the underlying brain damage caused by hypoxia/anoxia and its inflammatory, oxidative, and behavioral impairments.
PubMed: 38095869
DOI: 10.1080/1028415X.2023.2288387 -
International Ophthalmology Nov 2023To compare the efficacy of phakic intra-ocular lenses in isolation or in combination with corneal crosslinking (CXL) and/or intra-stromal corneal ring segments (ICRS) in... (Meta-Analysis)
Meta-Analysis Review
The efficacy of 2 different phakic intraocular lens implant in keratoconus as an isolated procedure or combined with collagen crosslinking and intra-stromal corneal ring segments: a systematic review and meta-analysis.
PURPOSE
To compare the efficacy of phakic intra-ocular lenses in isolation or in combination with corneal crosslinking (CXL) and/or intra-stromal corneal ring segments (ICRS) in keratoconus.
METHODS
Data extracted from the publications meeting the selection. The outcome parameters included mean pre- and post-operative uncorrected distance visual acuity, corrected distance visual acuity (CDVA), sphere and cylinder of refraction and complications. Available data analyzed with Cochrane Review Manager.
RESULTS
A total of 23 studies including 464 eyes were included. All the parameters showed significant improvement in all subgroups other than CDVA in ACPIOL + CXL subgroup and cylinder in PIOL + CXL subgroups. There was not a significant difference between PCPIOL and ACPIOL in the outcomes, exception was more improvement of CDVA in "ACPIOL only" than" PCPIOL only" subgroup.
CONCLUSION
Both PCPIOLs and ACPIOLs are comparably safe and efficient options in management of KCN and their efficacy significantly improves when combined with CXL/ICRS.
Topics: Humans; Phakic Intraocular Lenses; Photosensitizing Agents; Keratoconus; Riboflavin; Collagen; Corneal Topography; Cross-Linking Reagents; Corneal Stroma
PubMed: 37470861
DOI: 10.1007/s10792-023-02813-z -
Components of one-carbon metabolism and renal cell carcinoma: a systematic review and meta-analysis.European Journal of Nutrition Dec 2020Little is known about the aetiology of renal cell carcinoma (RCC). Components of one-carbon (1C) metabolism, which are required for nucleotide synthesis and methylation... (Meta-Analysis)
Meta-Analysis
PURPOSE
Little is known about the aetiology of renal cell carcinoma (RCC). Components of one-carbon (1C) metabolism, which are required for nucleotide synthesis and methylation reactions, may be related to risk of RCC but existing evidence is inconclusive. We conducted a systematic review and independent exposure-specific meta-analyses of dietary intake and circulating biomarkers of 1C metabolites and RCC risk.
METHODS
Medline and Embase databases were searched for observational studies investigating RCC or kidney cancer incidence or mortality in relation to components of 1C metabolism and 12 eligible articles were included in the meta-analyses. We used Bayesian meta-analyses to estimate summary relative risks (RRs) and 95% credible intervals (CrIs) comparing the highest versus lowest categories as well as the between-study heterogeneity.
RESULTS
We did not find convincing evidence of an association between any exposure (riboflavin, vitamin B, folate, vitamin B, methionine, homocysteine, choline, or betaine) and RCC risk. However, vitamin B biomarker status did have a protective (RR = 0.62) but imprecise (95% CrI 0.39-1.14) effect estimate and folate intake had a notable association as well (RR = 0.85, 95% CrI 0.71-1.01).
CONCLUSION
There was a lack of precision due largely to the low number of studies. Further investigation is warranted, especially for folate and vitamin B, which had consistent suggestive evidence of a protective effect for both dietary intake and biomarker status. A unique strength of this review is the use of Bayesian meta-analyses which allowed for robust estimation of between-study heterogeneity.
Topics: Bayes Theorem; Carbon; Carcinoma, Renal Cell; Folic Acid; Humans; Kidney Neoplasms; Risk Factors; Vitamin B 12; Vitamin B 6
PubMed: 32162043
DOI: 10.1007/s00394-020-02211-6 -
The American Journal of Clinical... Jun 2009National survey data of erythrocyte glutathione reductase activation coefficient (EGRac) indicate that suboptimal riboflavin status may be a problem in all population... (Review)
Review
BACKGROUND
National survey data of erythrocyte glutathione reductase activation coefficient (EGRac) indicate that suboptimal riboflavin status may be a problem in all population age groups, but the cutoff for deficiency is controversial. In addition, the effectiveness of different biomarkers of riboflavin status has not been critically evaluated.
OBJECTIVE
We aimed to assess the effectiveness of different biomarkers of riboflavin status through a systematic review of published riboflavin supplementation trials.
DESIGN
We structured our search strategy on Ovid MEDLINE, EMBASE (Ovid), and Cochrane databases; formal inclusion and exclusion criteria; data extraction; validity assessment; and meta-analysis.
RESULTS
Eighteen supplementation studies reporting up to 14 biomarkers were included. Sufficient data were available to show that EGRac (14 studies) and basal glutathione reductase activity (5 studies) were effective biomarkers of altered riboflavin intake (P < 0.00001), although substantial heterogeneity (I2 > 66%) that could not be explained by the subgroup analysis was observed. Plasma total homocysteine was not an effective biomarker of riboflavin status in the general population, but some evidence identified its potential usefulness specifically in those homozygous for a common polymorphism in the MTHFR gene.
CONCLUSIONS
The evidence suggests that EGRac is an effective biomarker of a change in riboflavin intake in populations with severe-to-normal baseline status. Studies of healthy populations that compare the response to low-dose supplementation among different age, sex, and MTHFR genotype groups are required to provide evidence for generating dietary riboflavin recommendations specific to different population subgroups. Further research into alternative biomarkers to EGRac is also required.
Topics: Biomarkers; Clinical Trials as Topic; Dietary Supplements; Glutathione Reductase; Homocysteine; Humans; Nutrition Assessment; Nutritional Status; Reference Values; Riboflavin; Vitamin B Complex
PubMed: 19403631
DOI: 10.3945/ajcn.2009.27230B -
Cornea Feb 2023The aim of this study was to compare the outcomes of 18 mW/cm 2 (5 minutes) versus 9 mW/cm 2 (10 minutes) accelerated corneal collagen cross-linking protocols in... (Meta-Analysis)
Meta-Analysis
PURPOSE
The aim of this study was to compare the outcomes of 18 mW/cm 2 (5 minutes) versus 9 mW/cm 2 (10 minutes) accelerated corneal collagen cross-linking protocols in patients with progressive keratoconus.
METHODS
A systematic review and meta-analysis were performed according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines, and electronic information was searched to identify studies comparing the outcomes of 5- versus 10-minute protocols in patients with progressive keratoconus. Mean changes in uncorrected visual acuity, best-corrected visual acuity, cylinder (diopters), thinnest corneal thickness, corneal keratometry values (K1 and K2), corneal high-order aberration (HOA), spherical aberration, coma, and trefoil were the primary outcome measures. Secondary outcome measures included the mean change in central corneal thickness and postoperative complications. Random effects modeling was used for the analysis.
RESULTS
Four studies that enrolled 329 eyes were included. The 10-minute protocol had significantly improved outcomes compared with the 5-minute protocol for the mean changes in K1 and K2 ( P < 0.00001), corneal total HOA ( P = 0.0002), and corneal coma ( P = 0.00001). However, no statistically significant differences were found between the 2 protocols in uncorrected visual acuity, best-corrected visual acuity, cylinder, thinnest corneal thickness, spherical aberration, or trefoil. The 5-minute protocol was associated with a significantly lower mean change in the central corneal thickness for secondary outcomes. In addition, no significant differences were found between the 2 protocols for postoperative complications.
CONCLUSIONS
The 10-minute protocol had better K1, K2, and HOA outcomes than the 5-minute protocol, but no statistically significant differences in the other outcomes.
Topics: Humans; Collagen; Corneal Cross-Linking; Corneal Topography; Cross-Linking Reagents; Keratoconus; Photochemotherapy; Photosensitizing Agents; Postoperative Complications; Riboflavin
PubMed: 36156043
DOI: 10.1097/ICO.0000000000003124