title: Establishment of a normal reference value of parathyroid hormone in a large healthy Chinese population and evaluation of its relation to bone turnover and bone mineral density.
abstract: A normal reference value of parathyroid hormone (PTH) was established for the first time in a large sample of healthy Chinese subjects by completely excluding interference of vitamin D deficiency. A high PTH level correlated significantly with an elevated bone turnover and a reduced bone mineral density (BMD).
  
  
  BACKGROUND
  The aims of this study are to establish a normal reference value for serum PTH and to evaluate the effect of parathyroid gland status on bone turnover and BMD.
  
  
  METHODS
  Our cross-sectional study included 1436 healthy individuals from 5 different Chinese cities. Concentrations of serum PTH, 25-hydroxyvitamin D (25OHD), procollagen I N-terminal peptide (P1NP, a bone formation marker), and carboxyl-terminal telopeptide of type I collagen (β-CTX, a bone resorption marker) were measured by electrochemiluminescence immunoassay. BMD was measured by dual-energy X-ray absorptiometry. The relation of PTH concentration to age, gender, height, and weight was examined. Reference values of PTH were established for all subjects and for subjects categorized by serum 25OHD concentrations. Correlations of PTH levels with bone turnover biomarkers and BMD were statistically analyzed.
  
  
  RESULTS
  Reference values of PTH were 8.84-69.95 pg/mL in all the subjects and 7.48-60.73 and 5.83-56.78 pg/mL in the subjects with serum 25OHD concentrations of ≥20 and ≥30 ng/mL, respectively. Serum PTH showed a negative linear correlation with 25OHD, and the breakpoint was 18.21 ng/mL, below which the PTH level rapidly increased. The increase in PTH levels with age showed a positive linear correlation with P1NP and β-CTX concentrations and a negative linear correlation with BMD at the lumbar spines and the femoral neck.
  
  
  CONCLUSIONS
  A reference value of PTH was established in a large sample of healthy Chinese subjects according to 25OHD status, gender, and age. A high PTH level correlated significantly with an elevated bone turnover and a reduced BMD.
authors.affiliation: Department of Endocrinology, Key Laboratory of Endocrinology of Ministry of Health, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, No. 1 Shuaifuyuan, Wangfujing Street, Beijing, 100730, China.
authors.forename: M
authors.initials: M
authors.lastname: Li
authors.affiliation: Department of Endocrinology, Key Laboratory of Endocrinology of Ministry of Health, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, No. 1 Shuaifuyuan, Wangfujing Street, Beijing, 100730, China.
authors.forename: F
authors.initials: F
authors.lastname: Lv
authors.affiliation: Department of Osteoporosis, Sixth People's Hospital, Shanghai Jiaotong University, No. 600 Yishan Road, Shanghai, 200233, China.
authors.forename: Z
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Department of Geriatrics, General Hospital of Guangzhou Military Command, No. 111 Liuhua Road, Guangzhou, 510010, China.
authors.forename: W
authors.initials: W
authors.lastname: Deng
authors.affiliation: Department of Laboratory, Hubei General Hospital, No. 238 Jiefang Road, Wuhan, 430060, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Orthopedics, The Second Affiliated Hospital of Chongqing Medical University, No. 76 Linjiang road, Chongqing, 400010, China.
authors.forename: Z
authors.initials: Z
authors.lastname: Deng
authors.affiliation: Department of Endocrinology, Key Laboratory of Endocrinology of Ministry of Health, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, No. 1 Shuaifuyuan, Wangfujing Street, Beijing, 100730, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Jiang
authors.affiliation: Department of Endocrinology, Key Laboratory of Endocrinology of Ministry of Health, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, No. 1 Shuaifuyuan, Wangfujing Street, Beijing, 100730, China.
authors.forename: O
authors.initials: O
authors.lastname: Wang
authors.affiliation: Department of Endocrinology, Key Laboratory of Endocrinology of Ministry of Health, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, No. 1 Shuaifuyuan, Wangfujing Street, Beijing, 100730, China.
authors.forename: X
authors.initials: X
authors.lastname: Xing
authors.affiliation: Department of Obstetrics and Gynecology, Peking Union Medical College, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, No. 1 Shuaifuyuan, Wangfujing Street, Beijing, 100730, China.
authors.forename: L
authors.initials: L
authors.lastname: Xu
authors.affiliation: Department of Endocrinology, Key Laboratory of Endocrinology of Ministry of Health, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, No. 1 Shuaifuyuan, Wangfujing Street, Beijing, 100730, China. xiaweibo8310@163.com.
authors.forename: W
authors.initials: W
authors.lastname: Xia
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000097:blood; D000886:Anthropometry / Q000379:methods; D044466:Asian People / Q000706:statistics & numerical data; D015415:Biomarkers / Q000097:blood; D015992:Body Mass Index; D015519:Bone Density / Q000502:physiology*; D016723:Bone Remodeling / Q000502:physiology*; D024042:Collagen Type I / Q000097:blood; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood* / Q000502:physiology; D010446:Peptide Fragments / Q000097:blood; D010455:Peptides / Q000097:blood; D011347:Procollagen / Q000097:blood; D012016:Reference Values; D012727:Sex Characteristics; D014807:Vitamin D / Q000031:analogs & derivatives / Q000097:blood; D055815:Young Adult
chemical_list: D015415:Biomarkers; D024042:Collagen Type I; C470125:PTH protein, human; D010281:Parathyroid Hormone; D010446:Peptide Fragments; D010455:Peptides; D011347:Procollagen; C052929:collagen type I trimeric cross-linked peptide; C047202:procollagen Type I N-terminal peptide; D014807:Vitamin D; C104450:25-hydroxyvitamin D
keywords: 25OHD; BMD; Bone turnover; P1NP; PTH; β-CTX