title: Prevalence of glucose intolerance in primary hyperparathyroidism and the benefit of parathyroidectomy.
abstract: BACKGROUND
  Increased prevalence of diabetes mellitus (DM) in primary hyperparathyroidism (PHPT) is established, but not glucose intolerance (GI), nor benefit from parathyroidectomy on GI. We determined these during management of a continuous series of patients with PHPT routinely followed after surgery.
  
  
  METHODS
  WHO criteria classified 75 g oral glucose tolerance tests (OGTT) in 51/54 consecutively proven PHPT patients, into normal glucose tolerance (NGT), DM, impaired glucose tolerance (IGT) or impaired fasting glucose (IFG); GI was derived by adding those with DM and IGT/IFG. OGTT were repeated after parathyroidectomy (mean follow up 2.4 +/- SD 1.6 years). Paired student t tests were used to compare fasting and 2-h plasma glucose (PG).
  
  
  RESULTS
  At presentation 32/54 patients (59%) had NGT, 10 IGT/IFG (19%) and 12 type 2 DM (22%), nine newly diagnosed. Before parathyroidectomy 17/35 patients had NGT (49%), 18 GI (51%), 12 DM (34%) and 6 IGT/IFG (17%). Five out of six patients with IGT/IFG had NGT, one with NGT developed IGT. At completion 23 patients (66%) had NGT, 12 GI (34%), 4 IGT/IFG (11%) and 8 DM (23%). After parathyroidectomy fasting and 2-h. PG fell in 30/34 normocalcaemic patients not on hypoglycaemic agents, 5.6 +/- 1.0 to 5.4 +/- 0.8 mmol/l, 7.2 +/- 3.0 to 6.3 +/- 3.1 mmol/l (p < 0.05, p < 0.01).
  
  
  CONCLUSIONS
  1. At presentation with PHPT, OGTT commonly identifies Type 2 DM and GI.2. After successful parathyroidectomy fasting and 2-h. PG fall significantly (p < 0.05, p < 0.01). DM and IGT/IFG often ameliorates to IGT or NGT, persistently.
authors.affiliation: Department of Medicine and Surgery, Halton General Hospital, Runcorn, Cheshire, UK. suzanne.kennedy@nch.nhs.uk
authors.forename: A A
authors.initials: AA
authors.lastname: Khaleeli
authors.forename: J N
authors.initials: JN
authors.lastname: Johnson
authors.forename: W H
authors.initials: WH
authors.lastname: Taylor
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003924:Diabetes Mellitus, Type 2 / Q000453:epidemiology / Q000517:prevention & control; D005260:Female; D018149:Glucose Intolerance / Q000453:epidemiology* / Q000209:etiology / Q000517:prevention & control; D005951:Glucose Tolerance Test; D006801:Humans; D049950:Hyperparathyroidism, Primary / Q000150:complications* / Q000453:epidemiology / Q000601:surgery; D008297:Male; D008875:Middle Aged; D016105:Parathyroidectomy; D015995:Prevalence; D006113:United Kingdom / Q000453:epidemiology