Obesity and Risk of Bladder Cancer: A Dose-Response Meta-Analysis of 15 Cohort Studies
Open Access
- 24 March 2015
- journal article
- research article
- Published by Public Library of Science (PLoS) in PLOS ONE
- Vol. 10 (3), e0119313
- https://doi.org/10.1371/journal.pone.0119313
Abstract
Epidemiological studies have reported inconsistent association between obesity and risk of bladder cancer, and the dose-response relationship between them has not been clearly defined. We carried out a meta-analysis to summarize available evidence from epidemiological studies on this point. Relevant articles were identified by searching the PubMed and Web of Science databases through September 30, 2014. We pooled the relative risks from individual studies using random-effect model, and the dose—response relationship was estimated by using restricted cubic spline model. Fifteen cohort studies with 38,072 bladder cancer cases among 14,201,500 participants were included. Compared to normal weight, the pooled relative risks and corresponding 95% confidence intervals of bladder cancer were 1.07(1.01-1.14) and 1.10(1.06-1.14) for preobese and obesity, with moderate (I2 = 37.6%, P = 0.029) and low (I2 = 15.5%, P = 0.241) heterogeneities between studies, respectively. In a dose-response meta-analysis, body mass index (BMI) was associated with bladder cancer risk in a linear fashion (P non-linearity = 0.467) and the risk increased by 4.2% for each 5 kg/m2 increase. No significant publication bias was found (P = 0.912 for Begg’s test, P = 0.712 for Egger’s test). Findings from this dose-response meta-analysis suggest obesity is associated with linear-increased risk of bladder cancer.Keywords
This publication has 52 references indexed in Scilit:
- Meta-Analysis for Linear and Nonlinear Dose-Response Relations: Examples, an Evaluation of Approximations, and SoftwareAmerican Journal of Epidemiology, 2011
- Body mass index, agricultural pesticide use, and cancer incidence in the Agricultural Health Study cohortCancer Causes & Control, 2010
- Dose‐response analyses using restricted cubic spline functions in public health researchStatistics in Medicine, 2010
- Diabetes mellitus, body size and bladder cancer risk in a prospective study of Swedish menEuropean Journal Of Cancer, 2008
- Cancer incidence and mortality in relation to body mass index in the Million Women Study: cohort studyBMJ, 2007
- Choice of exposure scores for categorical regression in meta-analysis: a case study of a common problemCancer Causes & Control, 2005
- Overweight, obesity and cancer: epidemiological evidence and proposed mechanismsNature Reviews Cancer, 2004
- Quantifying heterogeneity in a meta‐analysisStatistics in Medicine, 2002
- Validity of Self-Reported Waist and Hip Circumferences in Men and WomenEpidemiology, 1990
- Changes associated with quitting cigarette smoking: The Framingham StudyAmerican Heart Journal, 1975