title: Normocalcemic hyperparathyroidism and insulin resistance.
abstract: OBJECTIVE
  To determine whether insulin resistance (IR) accompanies normocalcemic primary hyperparathyroidism (NCPHP).
  
  
  METHODS
  Twenty-five patients with NCPHP and 25 age-, sex-, and body mass index (BMI)-matched controls were included the study. Patients were diagnosed NCPHP if their serum calcium (Ca) concentrations and ionized serum Ca levels were in the normal range but parathyroid hormone (PTH) levels were inappropriately and persistently high. Subjects with 25-hydroxyvitamin D (25[OH]D) levels ≥20 ng/dL were included in the study. The upper limit of PTH was calculated using a nomogram for each subject. Patients and controls underwent a standard 75-gram oral glucose tolerance test (OGTT). IR was assessed by the homeostasis model assessment (HOMA-IR) and insulin sensitivity index (ISogtt).
  
  
  RESULTS
  There were no differences between the demographic features of patients with NCPHP and the control group. IR frequency was not different between groups (P = .14). HOMA-IR was higher and ISogtt was lower in patients with NCPHP than the control group, but the differences were not significant (P = .17 and P = .22, respectively). We did not find any correlation between PTH and glucose metabolism markers (HOMA-IR, ISogtt, glycated hemoglobin [HbA1c], and BMI) in either of the groups.
  
  
  CONCLUSIONS
  The results of this study indicate that IR is not more common in patients with NCPHP, and PTH is not related to ISogtt or HOMA-IR.
authors.affiliation: Department of Endocrinology and Metabolic Diseases, Kartal Dr. Lutfi Kirdar Training and Research Hospital, Istanbul, Turkey.
authors.forename: Sule
authors.initials: S
authors.lastname: Temizkan
authors.affiliation: Department of Family and Community Medicine, Kartal Dr. Lutfi Kirdar Training and Research Hospital, Istanbul, Turkey.
authors.forename: Omer
authors.initials: O
authors.lastname: Kocak
authors.affiliation: Department of Endocrinology and Metabolic Diseases, Kartal Dr. Lutfi Kirdar Training and Research Hospital, Istanbul, Turkey.
authors.forename: Kadriye
authors.initials: K
authors.lastname: Aydin
authors.affiliation: Department of Endocrinology and Metabolic Diseases, Kartal Dr. Lutfi Kirdar Training and Research Hospital, Istanbul, Turkey.
authors.forename: Aysenur
authors.initials: A
authors.lastname: Ozderya
authors.affiliation: Department of Internal Medicine, Kartal Dr. Lutfi Kirdar Training and Research Hospital, Istanbul, Turkey.
authors.forename: Gulgun
authors.initials: G
authors.lastname: Arslan
authors.affiliation: Department of Biochemistry, Kartal Dr. Lutfi Kirdar Training and Research Hospital, Istanbul, Turkey.
authors.forename: Nihal
authors.initials: N
authors.lastname: Yucel
authors.affiliation: Department of Family and Community Medicine, Kartal Dr. Lutfi Kirdar Training and Research Hospital, Istanbul, Turkey.
authors.forename: Mehmet
authors.initials: M
authors.lastname: Sargin
mesh_terms: D000328:Adult; D002118:Calcium / Q000097:blood; D005260:Female; D005947:Glucose / Q000378:metabolism; D006801:Humans; D006961:Hyperparathyroidism / Q000378:metabolism*; D007333:Insulin Resistance; D008297:Male; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood
chemical_list: D010281:Parathyroid Hormone; D005947:Glucose; D002118:Calcium