title: Relationship between insulin sensitivity and bone mineral density in primary hyperparathyroidism.
abstract: BACKGROUND
  Evidence of crosstalk between bone and insulin metabolism has been identified. In primary hyperparathyroidism (PHPT), scant data exist on this relationship.
  
  
  OBJECTIVE
  To evaluate the relationship between insulin levels or sensitivity and bone mineral density (BMD) in PHPT.
  
  
  METHODS
  Two hundred and sixty-seven patients with PHPT without known diabetes mellitus were studied. Fasting blood glucose and insulin levels as well as BMD at lumbar spine, femoral neck and forearm were measured. Insulin sensitivity was assessed using Quantitative Insulin Sensitivity Check Index (QUICKI). The same parameters were measured 2 years (interquartile range 2·8 years) after surgery (PTX) in a subgroup of patients (n = 51).
  
  
  RESULTS
  In univariate analysis, a positive relationship between insulin levels and BMD (R = 0·17, P < 0·03) or T-score (R = 0·20, P < 0·005) was found at femoral neck level. Consequently, a negative relationship between QUICKI and femoral BMD (R = -0·20, P < 0·01) or T-score (R = -0·21, P < 0·004) was found. In multivariate analysis, when femoral BMD was the dependent variable, age (beta = -0·35, P < 0·000004), BMI (beta = 0·39, P < 0·00001), PTH (beta = -0·18, P < 0·05) and QUICKI (R = -0·15, P < 0·05) had an independent effect (R(2) = 0·29). Insulin levels and QUICKI did not change after PTX. No relationship was found between QUICKI or insulin levels at the time of diagnosis and change in BMD at any site at follow-up.
  
  
  CONCLUSIONS
  Our data show a weak relationship between insulin levels and/or insulin sensitivity and BMD in PHPT. However, the insulin state does not influence change in bone density after PTX in PHPT.
authors.affiliation: Division of Endocrinology, Department of Internal Medicine, S.Croce & Carle Hospital, Cuneo, Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: Gianotti
authors.forename: Francesco
authors.initials: F
authors.lastname: Tassone
authors.forename: Claudia
authors.initials: C
authors.lastname: Baffoni
authors.forename: Micaela
authors.initials: M
authors.lastname: Pellegrino
authors.forename: Sara
authors.initials: S
authors.lastname: Cassibba
authors.forename: Elena
authors.initials: E
authors.lastname: Castellano
authors.forename: Gianpaolo
authors.initials: G
authors.lastname: Magro
authors.forename: Flora
authors.initials: F
authors.lastname: Cesario
authors.forename: Gianluca
authors.initials: G
authors.lastname: Visconti
authors.forename: Giorgio
authors.initials: G
authors.lastname: Borretta
mesh_terms: D000368:Aged; D015519:Bone Density / Q000502:physiology*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D049950:Hyperparathyroidism, Primary / Q000378:metabolism*; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies
chemical_list: D007328:Insulin