title: Modifiable risk factors for the prevention of bladder cancer: a systematic review of meta-analyses.
abstract: Each year, 430,000 people are diagnosed with bladder cancer. Due to the high recurrence rate of the disease, primary prevention is paramount. Therefore, we reviewed all meta-analyses on modifiable risk factors of primary bladder cancer. PubMed, Embase and Cochrane database were systematically searched for meta-analyses on modifiable risk factors published between 1995 and 2015. When appropriate, meta-analyses (MA) were combined in meta-meta-analysis (MMA). If not, the most comprehensive MA was selected based on the number of primary studies included. Probability of causation was calculated for individual factors and a subset of lifestyle factors combined. Of 1496 articles identified, 5 were combined in MMA and 21 were most comprehensive on a single risk factor. Statistically significant associations were found for current (RR 3.14) or former (RR 1.83) cigarette smoking, pipe (RR 1.9) or cigar (RR 2.3) smoking, antioxidant supplementation (RR 1.52), obesity (RR 1.10), higher physical activity levels (RR 0.86), higher body levels of selenium (RR 0.61) and vitamin D (RR 0.75), and higher intakes of: processed meat (RR 1.22), vitamin A (RR 0.82), vitamin E (RR 0.82), folate (RR 0.84), fruit (RR 0.77), vegetables (RR 0.83), citrus fruit (RR 0.85), and cruciferous vegetables (RR 0.84). Finally, three occupations with the highest risk were tobacco workers (RR 1.72), dye workers (RR 1.58), and chimney sweeps (RR 1.53). The probability of causation for individual factors ranged from 4 to 68 %. The combined probability of causation was 81.8 %. Modification of lifestyle and occupational exposures can considerably reduce the bladder cancer burden. While smoking remains one of the key risk factors, also several diet-related and occupational factors are very relevant.
authors.affiliation: Department of Family and Community Medicine, College of Medicine, Taibah University, P.O. Box 42317, Madinah, 41541, Saudi Arabia.
authors.forename: Abdulmohsen H
authors.initials: AH
authors.lastname: Al-Zalabani
authors.affiliation: Department of Complex Genetics, School of Nutrition, and Translational Research in Metabolism (NUTRIM), Maastricht University Medical Centre, P. O. Box 616, 6200 MS, Maastricht, The Netherlands. k.stewart@maastrichtuniversity.nl.
authors.forename: Kelly F J
authors.identifier: 0000-0002-4451-6012
authors.initials: KF
authors.lastname: Stewart
authors.affiliation: Department of Complex Genetics, School of Nutrition, and Translational Research in Metabolism (NUTRIM), Maastricht University Medical Centre, P. O. Box 616, 6200 MS, Maastricht, The Netherlands.
authors.forename: Anke
authors.initials: A
authors.lastname: Wesselius
authors.affiliation: Department of Respiratory Medicine, School of Nutrition and Translational Research in Metabolism (NUTRIM), Maastricht University Medical Centre, P. O. Box 616, 6200 MS, Maastricht, The Netherlands.
authors.forename: Annemie M W J
authors.initials: AM
authors.lastname: Schols
authors.affiliation: Department of Complex Genetics, School of Nutrition, and Translational Research in Metabolism (NUTRIM), Maastricht University Medical Centre, P. O. Box 616, 6200 MS, Maastricht, The Netherlands.
authors.forename: Maurice P
authors.initials: MP
authors.lastname: Zeegers
mesh_terms: D004032:Diet; D015444:Exercise; D005260:Female; D006801:Humans; D008297:Male; D015201:Meta-Analysis as Topic; D016273:Occupational Exposure / Q000009:adverse effects; D009790:Occupations; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects; D001749:Urinary Bladder Neoplasms / Q000209:etiology* / Q000517:prevention & control
keywords: Bladder cancer; Lifestyle; Obesity; Occupation; Prevention; Risk factors; Smoking