title: Impact of the Introduction of Calcimimetics on Timing of Parathyroidectomy in Secondary and Tertiary Hyperparathyroidism.
abstract: BACKGROUND
  Hyperparathyroidism (HPT), both secondary and tertiary, is common in patients with end-stage renal disease, and is associated with severe bone disorders, cardiovascular complications, and increased mortality. Since the introduction of calcimimetics in 2004, treatment of HPT has shifted from surgery to predominantly medical therapy.
  
  
  OBJECTIVE
  The aim of this study was to evaluate the impact of this change of management on the HPT patient population before undergoing (sub-)total parathyroidectomy (PTx).
  
  
  METHODS
  Overall, 119 patients with secondary or tertiary HPT undergoing PTx were included in a retrospective, single-center cohort. Group A, who underwent PTx before January 2005, was compared with group B, who underwent PTx after January 2005. Patient characteristics, time interval between HPT diagnosis and PTx, and postoperative complications were compared.
  
  
  RESULTS
  Group A comprised 70 (58.8 %) patients and group B comprised 49 (41.2 %) patients. The median interval between HPT diagnosis and PTx was 27 (interquartile range [IQR] 12.5-48.0) and 49 (IQR 21.0-75.0) months for group A and B, respectively (p = 0.007). Baseline characteristics were similar among both groups. The median preoperative serum parathyroid hormone (PTH) level was 936 pg/mL (IQR 600-1273) for group A versus 1091 pg/mL (IQR 482-1373) for group B (p = 0.38). PTx resulted in a dramatic PTH reduction (less than twofold the upper limit: A, 80.0 %; B, 85.4 %), and postoperative complication rates were low in both groups (A: 7.8 %; B: 10.2 %) [p = 0.66].
  
  
  CONCLUSIONS
  The introduction of calcimimetics in 2004 is associated with a significant 2-year delay of surgery with continuously elevated preoperative PTH levels, while parathyroid surgery, even in a fragile population, is considered a safe and effective procedure.
authors.affiliation: Department of Surgery, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.
authors.forename: Willemijn Y
authors.initials: WY
authors.lastname: van der Plas
authors.affiliation: Department of Surgery, Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: Anton F
authors.initials: AF
authors.lastname: Engelsman
authors.affiliation: Department of Nephrology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.|Dialysis Center Groningen, Groningen, The Netherlands.
authors.forename: Akin
authors.initials: A
authors.lastname: Özyilmaz
authors.affiliation: Department of Endocrinology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.
authors.forename: Anouk N
authors.initials: AN
authors.lastname: van der Horst-Schrivers
authors.affiliation: Department of Clinical Chemistry, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.
authors.forename: Kornelis
authors.initials: K
authors.lastname: Meijer
authors.affiliation: Department of Surgery, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.|Department of Nuclear Medicine and Molecular Imaging and Intensive Care, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.
authors.forename: Gooitzen M
authors.initials: GM
authors.lastname: van Dam
authors.affiliation: Department of Surgery, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.
authors.forename: Robert A
authors.initials: RA
authors.lastname: Pol
authors.affiliation: Department of Nephrology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.
authors.forename: Martin H
authors.initials: MH
authors.lastname: de Borst
authors.affiliation: Department of Surgery, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands. s.kruijff@umcg.nl.
authors.forename: Schelto
authors.initials: S
authors.lastname: Kruijff
mesh_terms: D015415:Biomarkers / Q000097:blood; D057966:Calcimimetic Agents / Q000627:therapeutic use*; D002118:Calcium / Q000097:blood*; D000069449:Cinacalcet / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D006962:Hyperparathyroidism, Secondary / Q000188:drug therapy* / Q000601:surgery*; D007676:Kidney Failure, Chronic / Q000150:complications; D008297:Male; D008875:Middle Aged; D009426:Netherlands; D010281:Parathyroid Hormone / Q000097:blood; D016105:Parathyroidectomy; D012189:Retrospective Studies; D013997:Time Factors; D016896:Treatment Outcome; D014807:Vitamin D / Q000627:therapeutic use
chemical_list: D015415:Biomarkers; D057966:Calcimimetic Agents; D010281:Parathyroid Hormone; D014807:Vitamin D; D002118:Calcium; D000069449:Cinacalcet