title: Normocalcaemic hypoparathyroidism: prevalence and effect on bone status in older women. The OPUS study.
abstract: OBJECTIVE
  There are no consistent data on the prevalence and bone status of normocalcaemic hypoparathyroidism (NHYPO) as defined by normal adjusted calcium and low PTH level. Our aim was to determine the prevalence and the metabolic bone profile of NHYPO in older women, assessing its evolution over time. The second objective was to evaluate the prevalence of other calcium metabolic disorders.
  
  
  METHODS
  The Osteoporosis and Ultrasound Study (OPUS) is a 6-yr prospective study of fracture-related factors.
  
  
  METHODS
  A total of 2419 older women (age 55-79 yrs) and 258 younger women (age 30-40 yrs) participated. Complete follow-up data were available in 1416 subjects.
  
  
  METHODS
  After calculating the adjusted calcium according to James' formula, we identified 'abnormal' calcium and PTH using Mahalanobis distances and allocated older women into different pathological categories using reference intervals from the healthy young women.
  
  
  RESULTS
  We identified 57 subjects with NHYPO (2·4%). These women had lower than expected bone turnover as assessed by bone alkaline phosphatase (-14·5%, 95% CI: -26·2 to -3·0, P = 0·007), CTX (-66·3%, 95% CI: -74·0 to -56·4, P < 0·001) and osteocalcin (-36·8%, 95% CI: -45·6 to -26·6, P < 0·001). After 6 years, of the 35 NHYPO subjects with follow-up data, none developed overt hypoparathyroidism and only 15 (0·6%) subjects had persistent evidence of NHYPO. We also identified 86 subjects (3·6%) affected by hyperparathyroid hypercalcaemia.
  
  
  CONCLUSIONS
  This is the first large population-based study to investigate NHYPO in older women. NHYPO is fairly common, not always persistent and is characterized by low bone turnover.
authors: Academic Unit of Bone Metabolism, University of Sheffield, Sheffield, UK.|Department of Endocrinology and Diabetes, University Campus Bio-Medico, Rome, Italy.
authors: Andrea
authors: A
authors: Palermo
authors: School of Health and Related Research, University of Sheffield, Sheffield, UK.
authors: Richard
authors: R
authors: Jacques
authors: Academic Unit of Bone Metabolism, University of Sheffield, Sheffield, UK.
authors: Fatma
authors: F
authors: Gossiel
authors: School of Medicine and Dentistry, University of Aberdeen, Aberdeen, UK.
authors: David M
authors: DM
authors: Reid
authors: Cochin Hospital, Paris Descartes University, Paris, France.
authors: Christian
authors: C
authors: Roux
authors: Zentrum für Muskel- & Knochenforschung, Charité, Universitätsmedizin Berlin, Berlin, Germany.
authors: Dieter
authors: D
authors: Felsenberg
authors: Sektion Biomedizinische Bildgebung, Klinik für Radiologie und Neuroradiologie, Universitätsklinikum Schleswig-Holstein, Kiel, Germany.
authors: Claus-C
authors: CC
authors: Glueer
authors: Academic Unit of Bone Metabolism, University of Sheffield, Sheffield, UK.
authors: Richard
authors: R
authors: Eastell
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D015519:Bone Density; D002118:Calcium / Q000097:blood*; D015331:Cohort Studies; D005060:Europe / Q000453:epidemiology; D005260:Female; D050723:Fractures, Bone / Q000209:etiology / Q000517:prevention & control; D006801:Humans; D006996:Hypocalcemia / Q000150:complications / Q000175:diagnosis / Q000453:epidemiology / Q000378:metabolism / Q000473:pathology; D007011:Hypoparathyroidism / Q000150:complications / Q000175:diagnosis / Q000453:epidemiology / Q000378:metabolism / Q000473:pathology; D008875:Middle Aged; D015675:Osteocalcin / Q000097:blood; D010024:Osteoporosis / Q000453:epidemiology / Q000209:etiology / Q000378:metabolism / Q000473:pathology; D010281:Parathyroid Hormone / Q000097:blood*; D015995:Prevalence; D011446:Prospective Studies; D012307:Risk Factors
chemical_list: D010281:Parathyroid Hormone; D015675:Osteocalcin; D002118:Calcium