MP04-15 VASECTOMY AND THE RISK OF PROSTATE CANCER IN A PROSPECTIVE US COHORT: ANALYSIS IN THE PRESENCE OF SELECTION BIAS

Abstract

You have accessJournal of UrologyProstate Cancer: Epidemiology & Natural History I1 Apr 2016MP04-15 VASECTOMY AND THE RISK OF PROSTATE CANCER IN A PROSPECTIVE US COHORT: ANALYSIS IN THE PRESENCE OF SELECTION BIAS Michael Davenport, Shufeng Li, James Brooks, Mark Cullen, and Michael Eisenberg Michael DavenportMichael Davenport More articles by this author , Shufeng LiShufeng Li More articles by this author , James BrooksJames Brooks More articles by this author , Mark CullenMark Cullen More articles by this author , and Michael EisenbergMichael Eisenberg More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2016.02.1950AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Vasectomy is a common form of contraception in the United States with as many as 500,000 procedures completed annually as it is highly effective with few adverse effects. Yet, several studies have found an association between vasectomy and prostate cancer, while others have attributed the association to selection bias. Given that a randomized trial is unlikely, investigators have relied on observational data. We have used 3 analytic methods (multivariable adjustment, propensity score adjustment, and propensity score matching) to account for overt or hidden treatment biases to explore the relationship between vasectomy and prostate cancer. METHODS We evaluated the relationship between vasectomy and the risk of prostate cancer in the NIH-AARP Diet and Health Study with data accumulated over 18 years of follow up. Of the 100,134 men with vasectomy status available, prostate cancer was identified in 14,127 men and vasectomies were performed in 30,803 (30%). We used multivariate logistic regression analysis to examine the relationship of prostate cancer with a priori demographic, reproductive, socioeconomic and health factors. We performed propensity score adjusted and propensity score matched analysis. RESULTS Men utilizing vasectomy were more likely to be ever married, fathers, more educated, and white consistent with prior reports. Moreover, men who utilized vasectomy reported a higher prevalence of PSA and DRE prostate cancer screening. On multivariate analysis, there was no associated risk between a history of vasectomy and the onset of prostate cancer with a hazard ratio of 0.99 (95% CI, 0.94-1.04). No significant association was found when looking individually at low grade, high grade, or fatal prostate cancers. Propensity score based matching also yielded no significant association between vasectomy and prostate cancer (HR 1.06, 95% CI, 0.99-1.14). In a propensity score adjusted model, there was a slightly increased relative risk for all cases of prostate cancer (HR 1.07, 95% CI 1.003-1.13) that was not seen for low grade, high grade or fatal cancers individually. CONCLUSIONS With over 2 million person years of follow up in the current study, no convincing relationship between vasectomy and prostate cancer of any grade was identified. Estimates of the association between vasectomy and prostate cancer are sensitive to analytic method underscoring the tenuous nature of the connection. Given the differences between men who do and do not utilize vasectomy, selection bias appears likely to explain the very small excess seen for all cancers in a single model. © 2016FiguresReferencesRelatedDetails Volume 195Issue 4SApril 2016Page: e34 Advertisement Copyright & Permissions© 2016MetricsAuthor Information Michael Davenport More articles by this author Shufeng Li More articles by this author James Brooks More articles by this author Mark Cullen More articles by this author Michael Eisenberg More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...