title: Reference intervals for serum sex hormones in Han Chinese adult men from the Fangchenggang Area Male Health and Examination Survey.
abstract: BACKGROUND
  The aim was to establish reference intervals for serum sex hormones in adult men in the Fangchenggang area of China.
  
  
  METHODS
  Serum samples from 1,191 healthy male subjects, aged 20 - 69 years, were collected from the Fangchenggang Area Male Health and Examination Survey (FAMHES). Total testosterone (T), estrogen (E2), luteinising hormone (LH), follicle-stimulating hormone (FSH), and sex hormone-binding globulin (SHBG) were measured by electrochemiluminescence immunoassay (Elecsys). Free testosterone (FTc) was calculated from the concentrations of T, SHBG, and albumin.
  
  
  RESULTS
  The total nonparametric reference intervals for male sex hormones in our study were 12.6 - 37.0 nmol/L for T, 0.24 - 0.69 nmol/L for FTc, 65.4 - 207.7 pmol/L for E2, 2.2 - 11.6 IU/L for LH, 1.8 - 16.5 IU/L for FSH, and 18.2 - 95.1 nmol/L for SHBG. Age had a significant positive association with LH (r = 0.218), FSH (r = 0.427), and SHBG (r = 0.427) and a negative association with FTc (r = -0.383) and E2 (r = -0.098), but no significant association with T after adjustment for BMI. The age-dependent reference intervals were also calculated. Higher T and FTc concentrations were found in men who smoke compared with non-smokers, while no significant differences were found in E2, LH, FSH, and SHBG. When stratified for the number of cigarettes smoked per day, we found that the distributions of serum T levels were significantly higher only in the smokers who smoked 11 or more cigarettes a day than the non-smokers. Unlike T, the distributions of serum FTc levels were significantly higher only in the smokers who smoked less than 11 cigarettes a day, while the FSH levels were significantly lower.
  
  
  CONCLUSIONS
  In clinical practice, single reference intervals can be used for men aged 20 - 69 years for T and E2 measured with the Elecsys method, but separate age-dependent reference intervals should be used for FTc, LH, FSH, and SHBG. In addition, distinct reference intervals for T should be established for non-smokers or smokers (1 - 10 cigarettes/day) and smokers (> or = 11 cigarettes/day).
authors.affiliation: Department of Clinical Laboratory, First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi Zhuang Autonomous Region, PR China.
authors.forename: Xue
authors.initials: X
authors.lastname: Qin
authors.forename: Hui
authors.initials: H
authors.lastname: Lv
authors.forename: Zengnan
authors.initials: Z
authors.lastname: Mo
authors.forename: Zhiping
authors.initials: Z
authors.lastname: Chen
authors.forename: Liwen
authors.initials: L
authors.lastname: Lin
authors.forename: Tao
authors.initials: T
authors.lastname: Peng
authors.forename: Haiying
authors.initials: H
authors.lastname: Zhang
authors.forename: Xiaobo
authors.initials: X
authors.lastname: Yang
authors.forename: Yong
authors.initials: Y
authors.lastname: Gao
authors.forename: Aihua
authors.initials: A
authors.lastname: Tan
authors.forename: Shan
authors.initials: S
authors.lastname: Huang
authors.forename: Haiwei
authors.initials: H
authors.lastname: Li
authors.forename: Huiling
authors.initials: H
authors.lastname: Wu
authors.forename: Yan
authors.initials: Y
authors.lastname: Deng
authors.forename: Shan
authors.initials: S
authors.lastname: Li
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D002681:China; D016001:Confidence Intervals; D004967:Estrogens / Q000097:blood*; D005640:Follicle Stimulating Hormone / Q000097:blood*; D006306:Health Surveys; D006801:Humans; D007986:Luteinizing Hormone / Q000097:blood*; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D012738:Sex Hormone-Binding Globulin / Q000032:analysis*; D012907:Smoking / Q000378:metabolism; D013739:Testosterone / Q000097:blood*
chemical_list: D004967:Estrogens; D012738:Sex Hormone-Binding Globulin; D013739:Testosterone; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone