Introduction: Evidence of crosstalk between bone and insulin metabolism has been identified. In primary hyperparathyroidism (PHPT), scant data exist on this relationship.
Aim: To evaluate the relationship between insulin levels or sensitivity and bone mineral density (BMD) in PHPT.
Subject and 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.
© 2014 John Wiley & Sons Ltd.