title: The impact of obesity on prostate cancer recurrence observed after exclusion of diabetics.
abstract: OBJECTIVE
  Although overall there is a positive association between obesity and risk of prostate cancer (PrCa) recurrence, results of individual studies are somewhat inconsistent. We investigated whether the failure to exclude diabetics in prior studies could have increased the likelihood of conflicting results.
  
  
  METHODS
  A total of 610 PrCa patients who underwent radical prostatectomy between 2005 and 2012 were followed for recurrence, defined as a rise in serum PSA ≥ 0.2 ng/ml following surgery. Body mass index (BMI) and history of type 2 diabetes were documented prior to PrCa surgery. The analysis was conducted using Cox proportional hazard models.
  
  
  RESULTS
  Obesity (25.6 %) and diabetes (18.7 %) were common in this cohort. There were 87 (14.3 %) recurrence events during a median follow-up of 30.8 months after surgery among the 610 patients. When analyzed among all PrCa patients, no association was observed between BMI/obesity and PrCa recurrence. However, when analysis was limited to non-diabetics, obese men had a 2.27-fold increased risk (95 % CI 1.17-4.41) of PrCa recurrence relative to normal weight men, after adjusting for age and clinical/pathological tumor characteristics.
  
  
  CONCLUSIONS
  This study found a greater than twofold association between obesity/BMI and PrCa recurrence in non-diabetics. We anticipated these results because the relationship between BMI/obesity and the biologic factors that may underlie the PrCa recurrence-BMI/obesity association, such as insulin, may be altered by the use of anti-diabetes medication or diminished beta-cell insulin production in advanced diabetes. Studies to further assess the molecular factors that explain the BMI/obesity-PrCa recurrence relationship are warranted.
authors.affiliation: Department of Epidemiology and Population Health, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Belfer Building, Room 1315-B, Bronx, NY, 10461, USA, ilir.agalliu@einstein.yu.edu.
authors.forename: Ilir
authors.initials: I
authors.lastname: Agalliu
authors.forename: Steve
authors.initials: S
authors.lastname: Williams
authors.forename: Brandon
authors.initials: B
authors.lastname: Adler
authors.forename: Lagu
authors.initials: L
authors.lastname: Androga
authors.forename: Michael
authors.initials: M
authors.lastname: Siev
authors.forename: Juan
authors.initials: J
authors.lastname: Lin
authors.forename: Xiaonan
authors.initials: X
authors.lastname: Xue
authors.forename: Gloria
authors.initials: G
authors.lastname: Huang
authors.forename: Howard D
authors.initials: HD
authors.lastname: Strickler
authors.forename: Reza
authors.initials: R
authors.lastname: Ghavamian
mesh_terms: D000368:Aged; D015992:Body Mass Index; D003924:Diabetes Mellitus, Type 2 / Q000150:complications* / Q000473:pathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000473:pathology*; D009765:Obesity / Q000150:complications* / Q000473:pathology; D017430:Prostate-Specific Antigen / Q000097:blood; D011468:Prostatectomy; D011471:Prostatic Neoplasms / Q000097:blood / Q000150:complications / Q000473:pathology* / Q000601:surgery; D012189:Retrospective Studies
chemical_list: D017430:Prostate-Specific Antigen