title: Does prostate volume correlate with vitamin D deficiency among men undergoing prostate biopsy?
abstract: Recent studies demonstrate vitamin D is inversely correlated with BPH and prostate cancer (PCa) incidence. We aim to clarify the associations of vitamin D with prostate volume.
  
  
  
  This is an observational study investigating the associations of serum PSA, PSA density and prostate volume with serum 25-hydroxyvitamin D (25-OH D) in PCa patients and men with negative biopsies seen in outpatient urology clinics in Chicago, IL, USA. There were 571 men (40-79 years old) with elevated PSA or abnormal digital rectal examination with available prostate volume recorded from initial biopsy. The primary outcomes were the unadjusted associations of serum 25-OH D deficiency with prostate volume. The secondary outcomes were the adjusted associations using linear and logistic regression analysis.
  
  
  
  On univariate analysis, serum 25-OH D<20 ng ml-1inversely correlated with prostate volume among all men undergoing transrectal ultrasonography (P=0.02), and this relationship remained significant for men with negative biopsy on stratified analysis. In adjusted models, controlling for age, serum PSA, 5-α reductase inhibitors use, obesity and PCa diagnosis, prostate volume was inversely associated with vitamin D (P<0.05) using serum vitamin D as a continuous and categorical variable. Logistic regression model also demonstrated an inverse association between vitamin D (continuous and categorical) and prostate volume ⩾40 grams.
  
  
  
  Serum 25-OH D levels are inversely associated with overall prostate volume and enlarged prostate gland (⩾40 grams), especially in men with benign prostatic disease. Given the largely non-toxic effect of supplementation, consideration should be given to assessing vitamin D levels in men with benign prostatic disease in addition, to malignant prostatic disease.
authors.affiliation: Department of Urology, Northwestern University, Chicago, IL, USA.
authors.forename: A B
authors.initials: AB
authors.lastname: Murphy
authors.affiliation: Cleveland Clinic, Cleveland, OH, USA.
authors.forename: Y A
authors.initials: YA
authors.lastname: Nyame
authors.affiliation: University of Arizona Cancer Center, Tucson, AZ.
authors.forename: K
authors.initials: K
authors.lastname: Batai
authors.affiliation: Department of Surgery, Wayne State University, Detroit, MI, USA.
authors.forename: R
authors.initials: R
authors.lastname: Kalu
authors.affiliation: Department of Urology, Northwestern University, Chicago, IL, USA.
authors.forename: A
authors.initials: A
authors.lastname: Khan
authors.affiliation: Department of Urology, Northwestern University, Chicago, IL, USA.
authors.forename: P
authors.initials: P
authors.lastname: Gogana
authors.affiliation: Department of Urology, Northwestern University, Chicago, IL, USA.
authors.forename: M
authors.initials: M
authors.lastname: Dixon
authors.affiliation: University of Illinois at Chicago, Chicago, IL, USA.
authors.forename: V
authors.initials: V
authors.lastname: Macias
authors.affiliation: University of Illinois at Chicago, Chicago, IL, USA.
authors.forename: A
authors.initials: A
authors.lastname: Kajdacsy-Balla
authors.affiliation: Cook County Health and Hospitals System, Chicago, IL, USA.
authors.forename: C M P
authors.initials: CM
authors.lastname: Hollowell
authors.affiliation: Department of Urology, Northwestern University, Chicago, IL, USA.
authors.forename: W J
authors.initials: WJ
authors.lastname: Catalona
authors.affiliation: University of Arizona Cancer Center, Tucson, AZ.
authors.forename: R
authors.initials: R
authors.lastname: Kittles
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers; D001706:Biopsy; D003430:Cross-Sectional Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009929:Organ Size; D011467:Prostate / Q000378:metabolism* / Q000473:pathology*; D011470:Prostatic Hyperplasia / Q000453:epidemiology / Q000209:etiology / Q000378:metabolism / Q000473:pathology; D011471:Prostatic Neoplasms / Q000453:epidemiology / Q000209:etiology* / Q000378:metabolism / Q000473:pathology*; D014807:Vitamin D / Q000378:metabolism*; D014808:Vitamin D Deficiency / Q000150:complications*
chemical_list: D015415:Biomarkers; D014807:Vitamin D