title: Prostate-specific antigen lowering effect of metabolic syndrome is influenced by prostate volume.
abstract: OBJECTIVE
  To investigate the influence of metabolic syndrome on prostate-specific antigen levels by considering prostate volume and plasma volume.
  
  
  METHODS
  We retrospectively analyzed 4111 men who underwent routine check-ups including prostate-specific antigen and transrectal ultrasonography. The definition of metabolic syndrome was based on the modified Adult Treatment Panel III criteria. Prostate-specific antigen mass density (prostate-specific antigen × plasma volume / prostate volume) was calculated for adjusting plasma volume and prostate volume. We compared prostate-specific antigen and prostate-specific antigen mass density levels of participants with metabolic syndrome (metabolic syndrome group, n = 1242) and without metabolic syndrome (non-prostate-specific antigen metabolic syndrome group, n = 2869). To evaluate the impact of metabolic syndrome on prostate-specific antigen, linear regression analysis for the natural logarithm of prostate-specific antigen was used.
  
  
  RESULTS
  Patients in the metabolic syndrome group had significantly older age (P < 0.001), larger prostate volume (P < 0.001), higher plasma volume (P < 0.001) and lower mean serum prostate-specific antigen (non-metabolic syndrome group vs metabolic syndrome group; 1.22 ± 0.91 vs 1.15 ± 0.76 ng/mL, P = 0.006). Prostate-specific antigen mass density in the metabolic syndrome group was still significantly lower than that in the metabolic syndrome group (0.124 ± 0.084 vs 0.115 ± 0.071 μg/mL, P = 0.001). After adjusting for age, prostate volume and plasma volume using linear regression model, the presence of metabolic syndrome was a significant independent factor for lower prostate-specific antigen (prostate-specific antigen decrease by 4.1%, P = 0.046).
  
  
  CONCLUSIONS
  Prostate-specific antigen levels in patients with metabolic syndrome seem to be lower, and this finding might be affected by the prostate volume.
authors.affiliation: Department of Urology, Konkuk University Hospital, Seoul, Korea.
authors.forename: Woo Suk
authors.initials: WS
authors.lastname: Choi
authors.affiliation: Department of Internal Medicine, Healthcare System Gangnam Center, Seoul National University Hospital, Seoul, Korea.
authors.forename: Nam Ju
authors.initials: NJ
authors.lastname: Heo
authors.affiliation: Department of Urology, Seoul National University Hospital, Seoul, Korea.
authors.forename: Jae-Seung
authors.initials: JS
authors.lastname: Paick
authors.affiliation: Department of Urology, Seoul National University Boramae Hospital, Seoul, Korea.
authors.forename: Hwancheol
authors.initials: H
authors.lastname: Son
mesh_terms: D000367:Age Factors; D015992:Body Mass Index; D006801:Humans; D008297:Male; D024821:Metabolic Syndrome / Q000097:blood / Q000378:metabolism* / Q000503:physiopathology; D008875:Middle Aged; D010953:Plasma Volume; D011467:Prostate / Q000000981:diagnostic imaging / Q000378:metabolism / Q000503:physiopathology*; D017430:Prostate-Specific Antigen / Q000097:blood*; D012189:Retrospective Studies; D014463:Ultrasonography
chemical_list: D017430:Prostate-Specific Antigen
keywords: metabolic syndrome; prostate; prostate volume; prostate-specific antigen; transrectal ultrasonography