title: Effects of Vitamin and Antioxidant Supplements in Prevention of Bladder Cancer: a Meta-Analysis of Randomized Controlled Trials.
abstract: This study aimed to investigate the effects of vitamin and antioxidant supplements in the prevention of bladder cancer using a meta-analysis of randomized controlled trials (RCTs). Fourteen RCTs were included in the final analysis. In a fixed-effect meta-analysis, vitamin and antioxidant supplements showed no preventive effect for bladder cancer (relative risk [RR] = 1.04; 95% confidence interval [CI] 0.92-1.17; I² = 39.7%). Also, there was no preventive effect of these supplements in the subgroup meta-analyses by various factors such as type of supplements, type of cancer prevention, methodological quality, providers of supplements, type of control group, and number of participants. Among the subgroup analyses by type of supplements, beta-carotene supplementation alone marginally increased the risk of bladder cancer (RR = 1.44; 95% CI 1.00-2.09; I² = 0.0%; n = 3). The current meta-analysis found that vitamin and antioxidant supplements have no preventive effect against bladder cancer.
authors.affiliation: Department of Family Medicine, National Cancer Center, Goyang, Korea.|Department of Family Medicine, Yonsei University Graduate School, Seoul, Korea.
authors.forename: So Jung
authors.identifier: http://orcid.org/0000-0002-5444-0250
authors.initials: SJ
authors.lastname: Park
authors.affiliation: Department of Family Medicine, National Cancer Center, Goyang, Korea.|Department of Cancer Control and Policy, Graduate School of Cancer Science and Policy, National Cancer Center, Goyang, Korea.|Molecular Epidemiology Branch, Division of Cancer Epidemiology and Prevention, Research Institute, National Cancer Center, Goyang, Korea.|Center for Cancer Prevention and Detection, Hospital, National Cancer Center, Goyang, Korea. msk@ncc.re.kr.
authors.forename: Seung Kwon
authors.identifier: http://orcid.org/0000-0001-8911-1345
authors.initials: SK
authors.lastname: Myung
authors.affiliation: Department of Family Medicine, National Cancer Center, Goyang, Korea.
authors.forename: Yunju
authors.identifier: http://orcid.org/0000-0002-4755-1868
authors.initials: Y
authors.lastname: Lee
authors.affiliation: Department of Family Medicine, Yonsei University College of Medicine, Gangnam Severance Hospital, Seoul, Korea.
authors.forename: Yong Jae
authors.identifier: http://orcid.org/0000-0002-6697-476X
authors.initials: YJ
authors.lastname: Lee
mesh_terms: D000975:Antioxidants / Q000627:therapeutic use*; D016208:Databases, Factual; D019587:Dietary Supplements; D006801:Humans; D016032:Randomized Controlled Trials as Topic; D012306:Risk; D001749:Urinary Bladder Neoplasms / Q000473:pathology / Q000517:prevention & control*; D014815:Vitamins / Q000627:therapeutic use*; D019207:beta Carotene / Q000627:therapeutic use
chemical_list: D000975:Antioxidants; D014815:Vitamins; D019207:beta Carotene
keywords: Antioxidant; Bladder Cancer; Meta-Analysis; Randomized Controlled Trials; Vitamin