Prostate cancer risk in relation to obesity and diabetes: A pooled analysis (Cohort Consortium Study)
Principal Investigator
About this CDAS Project
Study
PLCO
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Project ID
2011-0053
Initial CDAS Request Approval
Mar 25, 2011
Title
Prostate cancer risk in relation to obesity and diabetes: A pooled analysis (Cohort Consortium Study)
Summary
We have been approved by the Cohort Consortium to conduct a pooled analysis of several cohorts with over 40,000 prostate cancer cases to tease out the individual and joint associations of diabetes, obesity, and genetics with prostate cancer risk. This pooled analysis will include over 6,800 cases of high-grade tumors. In this PAF, we are asking for approval to use PLCO data for the pooled analysis. The relationships among prostate cancer, obesity, insulin resistance, and diabetes are complex and inconclusive. All four of these conditions are very common, with rising incidence rates in most populations. Thus, a better understanding of their relationships is critical and has considerable potential for cancer prevention and important public health implications. However, because of the divergent relationships between obesity and high- and low-grade prostate cancer and the inverse association between diabetes and overall prostate cancer, a large and well-powered study with a sufficient number of aggressive prostate tumors will be needed to tease out these relationships and to determine definitively the role of obesity and diabetes in prostate cancer etiology. We will first determine the individual effects of presence of diabetes, duration and severity of diabetes, insulin resistance, and obesity (including overall and abdominal obesity) on aggressive prostate cancer; the Cohort Consortium has at least 43,000 prostate cancer cases, including 6,800 high-grade tumors. A Cox proportional-hazards regression model will be used to evaluate the independent effects of these risk factors on prostate cancer risk. We will also investigate if these risk factors can jointly alter risk of aggressive prostate cancer by conducting stratified and joint effects analysis. Cohort-specific and heterogeneity of the results across cohorts will also be evaluated.
Aims
We hypothesize that prostate cancer aggressiveness is influenced by diabetes and obesity. We further hypothesize that these risk factors will jointly alter risk for aggressive prostate cancer. We propose to pool data from several studies within the Cohort Consortium (including the PLCO) to address the following aims: Aim 1: To determine if presence of diabetes, duration and/or severity of diabetes, insulin resistance, and obesity (including overall and abdominal obesity), affects risk for aggressive prostate cancer. Aim 2: To determine if presence of two or more of the risk factors effects (independently or jointly) alters risk for aggressive prostate.