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Meta-Analysis
. 2013 Nov 25;8(11):e81577.
doi: 10.1371/journal.pone.0081577. eCollection 2013.

Effect of B-vitamin supplementation on stroke: a meta-analysis of randomized controlled trials

Chi Zhang  1 , Feng-Ling Chi, Tian-Hao Xie, Yu-Hao Zhou
Affiliations
Meta-Analysis

Effect of B-vitamin supplementation on stroke: a meta-analysis of randomized controlled trials

Chi Zhang et al. PLoS One. .

Abstract

Background: B vitamins have been extensively used to reduce homocysteine levels; however, it remains uncertain whether B vitamins are associated with a reduced risk of stroke. Our aim was to evaluate the effects of B vitamins on stroke.

Methodology and principal findings: We systematically searched PubMed, EmBase, and the Cochrane Central Register of Controlled Trials to identify studies for our analysis. Relative risk (RR) was used to measure the effect of B-vitamin supplementation on the risk of stroke. The analysis was further stratified based on factors that could affect the treatment effects. Of the 13,124 identified articles, we included 18 trials reporting data on 57,143 individuals and 2,555 stroke events. B-vitamin supplementation was not associated with a significant reduction in the risk of stroke (RR, 0.91, 95%CI: 0.82-1.01, P = 0.075; RD, -0.003, 95%CI: -0.007-0.001, P = 0.134). Subgroup analyses suggested that B-vitamin supplementation might reduce the risk of stroke if included trials had a man/woman ratio of more than 2 or subjects received dose of folic acid less than 1 mg. Furthermore, in a cumulative meta-analysis for stroke, the originally proposed nonsignificant B-vitamin effect was refuted by the evidence accumulated up to 2006. There is a small effect with borderline statistical significance based on data gathered since 2007.

Conclusions/significance: Our study indicates that B-vitamin supplementation is not associated with a lower risk of stroke based on relative and absolute measures of association. Subgroup analyses suggested that B-vitamin supplementation can effectively reduce the risk of stroke if included trials had a man/woman ratio of more than 2 or subjects received dose of folic acid less than 1 mg.

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Conflict of interest statement

Competing Interests: The authors have declared that no competing interests exist.

Figures

Figure 1
Figure 1. Effect of B vitamins supplementation on the risk of stroke.
Figure 2
Figure 2. L’Abbe plots for stroke.
Figure 3
Figure 3. Funnel plots for stroke.
See this image and copyright information in PMC

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References

    1. Williams GR, Jiang JG, Matchar DB, Samsa GP (1999) Incidence and occurrence of total (first-ever and recurrent) stroke. Stroke 30: 2523–2528. doi:10.1161/01.STR.30.12.2523. PubMed: 10582972. - DOI - PubMed
    1. Yusuf S, Reddy S, Ounpuu S, Anand S (2001) Global burden of cardiovascular diseases, I: general considerations, the epidemiologic transition, risk factors, and impact of urbanization. Circulation 104: 2746–2753. doi:10.1161/hc4601.099487. PubMed: 11723030. - DOI - PubMed
    1. Brattstrom LE, Hardebo JE, Hultberg BL (1984) Moderate homocysteinemia-a possible risk factor for arteriosclerotic cerebrovascular disease. Stroke 15: 1012–1016. doi:10.1161/01.STR.15.6.1012. PubMed: 6506111. - DOI - PubMed
    1. Lindgren A, Brattström L, Norrving B, Hultberg B, Andersson A et al. (1995) Plasma homocysteine in the acute and convalescent phases after stroke. Stroke 26: 795- 800. doi:10.1161/01.STR.26.5.795. PubMed: 7740569. - DOI - PubMed
    1. Vollset SE, Refsum H, Tverdal A, Nygård O, Nordrehaug JE et al. (2001) Plasma total homocysteine and cardiovascular and noncardiovascular mortality: the Hordaland Homocysteine Study. Am J Clin Nutr 74: 130–136. PubMed: 11451728. - PubMed

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