title: Effect of vitamin D supplementation on the level of circulating high-sensitivity C-reactive protein: a meta-analysis of randomized controlled trials.
abstract: Vitamin D might elicit protective effects against cardiovascular disease by decreasing the level of circulating high-sensitivity C-reactive protein (hs-CRP), an inflammatory marker. Thus, we conducted a meta-analysis of randomized controlled trials to evaluate the association of vitamin D supplementation with circulating hs-CRP level. A systematic literature search was conducted in September 2013 (updated in February 2014) via PubMed, Web of Science, and Cochrane library to identify eligible studies. Either a fixed-effects or a random-effects model was used to calculate pooled effects. The results of the meta-analysis of 10 trials involving a total of 924 participants showed that vitamin D supplementation significantly decreased the circulating hs-CRP level by 1.08 mg/L (95% CI, -2.13, -0.03), with the evidence of heterogeneity. Subgroup analysis suggested a higher reduction of 2.21 mg/L (95% CI, -3.50, -0.92) among participants with baseline hs-CRP level ≥5 mg/L. Meta-regression analysis further revealed that baseline hs-CRP level, supplemental dose of vitamin D and intervention duration together may be attributed to the heterogeneity across studies. In summary, vitamin D supplementation is beneficial for the reduction of circulating hs-CRP. However, the result should be interpreted with caution because of the evidence of heterogeneity.
authors.affiliation: Department of Nutrition and Food Hygiene, School of Public Health, Soochow University, 199 Renai Road, Suzhou 215123, China. 18862247673@163.com.
authors.forename: Neng
authors.initials: N
authors.lastname: Chen
authors.affiliation: Department of Nutrition and Food Hygiene, School of Public Health, Soochow University, 199 Renai Road, Suzhou 215123, China. zhxwan@suda.edu.cn.
authors.forename: Zhongxiao
authors.initials: Z
authors.lastname: Wan
authors.affiliation: Department of Nutrition and Food Hygiene, School of Public Health, Soochow University, 199 Renai Road, Suzhou 215123, China. sfhan@suda.edu.cn.
authors.forename: Shu-Fen
authors.initials: SF
authors.lastname: Han
authors.affiliation: Medical College of Soochow University, 199 Renai Road, Suzhou 215123, China. bingyanli@suda.edu.cn.
authors.forename: Bing-Yan
authors.initials: BY
authors.lastname: Li
authors.affiliation: Department of Labor Hygiene and Environmental Health, School of Public Health of Soochow University, 199 Renai Road, Suzhou 215123, China. zhangzengli@suda.edu.cn.
authors.forename: Zeng-Li
authors.initials: ZL
authors.lastname: Zhang
authors.affiliation: Department of Nutrition and Food Hygiene, School of Public Health, Soochow University, 199 Renai Road, Suzhou 215123, China. qinliqiang@suda.edu.cn.
authors.forename: Li-Qiang
authors.initials: LQ
authors.lastname: Qin
mesh_terms: D002097:C-Reactive Protein / Q000378:metabolism*; D006801:Humans; D016032:Randomized Controlled Trials as Topic; D014807:Vitamin D / Q000008:administration & dosage* / Q000494:pharmacology*
chemical_list: D014807:Vitamin D; D002097:C-Reactive Protein