title: Dissecting the association between metabolic syndrome and prostate cancer risk: analysis of a large clinical cohort.
abstract: BACKGROUND
  A biologic rationale exists for the association between metabolic syndrome (MetS) and prostate cancer (PCa). However, epidemiologic studies have been conflicting.
  
  
  OBJECTIVE
  To evaluate the association between MetS and the odds of PCa diagnosis in men referred for biopsy.
  
  
  METHODS
  Patients without prior PCa diagnosis undergoing prostate biopsy were identified from a large prostate biopsy cohort (in Toronto, Canada). The definition of MetS was based on the most recent interim joint consensus definition, requiring any three of five components (obesity, elevated blood pressure, diabetes or impaired fasting glucose, low high-density lipoprotein-cholesterol, and hypertriglyceridemia). Both the individual components of MetS and the cumulative number of MetS components were evaluated.
  
  
  METHODS
  The outcomes were PCa detection overall, clinically significant PCa (CSPC; defined as any Gleason pattern ≥ 4, >50% involvement of a single biopsy core, or more than one of three total number of cores involved), and intermediate- or high-grade PCa (I-HGPC; Gleason 7-10). Tests for trend and multivariable logistic regression analyses were performed.
  
  
  CONCLUSIONS
  Of 2235 patients, 494 (22.1%) had MetS. No individual MetS component was independently associated with PCa. However, increasing number of MetS components was associated with higher PCa grade (p<0.001), as well as progressively higher odds of PCa outcomes (three or more; ie, MetS) compared with no MetS components: Odds ratios were 1.54 for PCa overall (95% confidence interval [CI], 1.17-2.04; p=0.002), 1.56 for CSPC (95% CI, 1.17-2.08; p=0.002), and 1.56 for I-HGPC (95% CI, 1.16-2.10; p=0.003) in multivariable analyses. The main limitation is the retrospective design.
  
  
  CONCLUSIONS
  Although the individual MetS components are not independently associated with PCa outcomes, MetS is significantly associated with higher odds of PCa diagnosis, CSPC, and I-HGPC. There is a biologic gradient between the number of MetS components and the risk of PCa, as well as cancer grade.
  
  
  RESULTS
  Metabolic syndrome is a collection of metabolic abnormalities that increases one's risk for heart disease. Our study shows that an increasing degree of metabolic abnormality is also associated with an increased risk of diagnosis of overall and aggressive prostate cancer.
authors.affiliation: Division of Urology, Department of Surgery, University Health Network, University of Toronto, Toronto, Ontario, Canada. Electronic address: bimal.bhindi@mail.utoronto.ca.
authors.forename: Bimal
authors.initials: B
authors.lastname: Bhindi
authors.affiliation: Division of Urology, Department of Surgery, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Locke
authors.affiliation: Department of Medicine, University Health Network, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Shabbir M H
authors.initials: SMH
authors.lastname: Alibhai
authors.affiliation: Division of Urology, Department of Surgery, University Health Network, University of Toronto, Toronto, Ontario, Canada; Institute for Clinical Evaluative Sciences, University of Toronto, Ontario, Canada.
authors.forename: Girish S
authors.initials: GS
authors.lastname: Kulkarni
authors.affiliation: Division of Urology and Davidoff Cancer Center, Rabin Medical Center, Petah Tikva, Israel.
authors.forename: David S
authors.initials: DS
authors.lastname: Margel
authors.affiliation: Division of Urology, Department of Surgery, University Health Network, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Hamilton
authors.affiliation: Division of Urology, Department of Surgery, University Health Network, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Antonio
authors.initials: A
authors.lastname: Finelli
authors.affiliation: Division of Urology, Department of Surgery, University Health Network, University of Toronto, Toronto, Ontario, Canada.
authors.forename: John
authors.initials: J
authors.lastname: Trachtenberg
authors.affiliation: Division of Urology, Department of Surgery, University Health Network, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Alexandre R
authors.initials: AR
authors.lastname: Zlotta
authors.affiliation: Department of Medical Imaging, University Health Network, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Ants
authors.initials: A
authors.lastname: Toi
authors.affiliation: Division of Urology, Department of Surgery, University Health Network, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Karen M
authors.initials: KM
authors.lastname: Hersey
authors.affiliation: Department of Pathology, University Health Network, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Andrew
authors.initials: A
authors.lastname: Evans
authors.affiliation: Department of Pathology, University Health Network, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Theodorus H
authors.initials: TH
authors.lastname: van der Kwast
authors.affiliation: Division of Urology, Department of Surgery, University Health Network, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Neil E
authors.initials: NE
authors.lastname: Fleshner
mesh_terms: D000368:Aged; D001706:Biopsy; D003924:Diabetes Mellitus, Type 2 / Q000453:epidemiology; D006801:Humans; D006973:Hypertension / Q000453:epidemiology; D015228:Hypertriglyceridemia / Q000453:epidemiology; D008297:Male; D024821:Metabolic Syndrome / Q000453:epidemiology*; D008875:Middle Aged; D060787:Neoplasm Grading; D009765:Obesity / Q000453:epidemiology; D016017:Odds Ratio; D009864:Ontario / Q000453:epidemiology; D011467:Prostate / Q000473:pathology*; D011471:Prostatic Neoplasms / Q000453:epidemiology* / Q000473:pathology*; D012189:Retrospective Studies; D012307:Risk Factors
keywords: Metabolic syndrome; Prostate biopsy; Prostatic neoplasms