title: Vitamin D is significantly associated with total testosterone and sex hormone-binding globulin in Malaysian men.
abstract: OBJECTIVE
  Cross-sectional studies in the Caucasian population have shown a significant relationship between vitamin D and testosterone levels, but data in the Asian population are limited. This study aimed to determine the association between vitamin D and testosterone levels in Malaysian men.
  
  
  METHODS
  Chinese and Malay men (n = 382) aged 20 years or above residing in the Klang Valley, Malaysia were recruited. Their fasting blood was collected for serum testosterone, sex hormone-binding globulin (SHBG) and 25-hydroxyvitamin D (25(OH)D) assays. Relationship between 25(OH)D and testosterone levels was analyzed using multiple regression analysis. Testosterone and SHBG levels among subjects with different vitamin D status were compared using univariate analysis. Confounders such as age, ethnicity and body mass index (BMI) were adjusted.
  
  
  RESULTS
  25(OH)D was significantly and positively associated with total testosterone and SHBG levels before and after adjustment for age and ethnicity (p < 0.05). Only association with SHBG remained significant after further adjustment for BMI (p < 0.05). Total testosterone and SHBG values displayed an increasing trend from subjects with vitamin D deficiency to those with optimal level (p < 0.05). The trend was attenuated after adjustment for BMI (p > 0.05).
  
  
  CONCLUSIONS
  25(OH)D is significantly associated with total testosterone and SHBG in Malaysian men but this association is BMI-dependent.
authors.affiliation: a Department of Pharmacology and.
authors.forename: Kok-Yong
authors.initials: KY
authors.lastname: Chin
authors.affiliation: a Department of Pharmacology and.
authors.forename: Soelaiman
authors.initials: S
authors.lastname: Ima-Nirwana
authors.affiliation: b Department of Biochemistry, Faculty of Medicine , Universiti Kebangsaan Malaysia , Kuala Lumpur , Malaysia.
authors.forename: Wan Zurinah
authors.initials: WZ
authors.lastname: Wan Ngah
mesh_terms: D000328:Adult; D044466:Asian People; D003430:Cross-Sectional Studies; D006801:Humans; D008296:Malaysia; D008297:Male; D008875:Middle Aged; D012044:Regression Analysis; D012738:Sex Hormone-Binding Globulin / Q000032:analysis*; D013739:Testosterone / Q000097:blood*; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood
chemical_list: D012738:Sex Hormone-Binding Globulin; D014807:Vitamin D; D013739:Testosterone; C104450:25-hydroxyvitamin D
keywords: Men; sex hormone-binding globulin; testosterone; vitamin D