Endocrine Abstracts

Introduction: High level of Parathormone (PTH) impair bone health by increasing the risk of fracture. The aim is to determine the threshold value of PTH elevation to accompany deficiency or failure of Vit D. This may be an important parameter in assessing bone metabolism in clinical practice.

Material and method: 931 patients who were referred to the endocrinology clinic were retrospectively studied and 880 patients diagnosed with Vit D deficiency included to the study. Patients were divided into three groups according to their vitamin D levels: <10 ng/dL, 10–19.99 ng/dl, 20–29.99 ng/dl. The mean Ca, P, PTH, Vit D, ALP levels were calculated.

RESULTS: 880 patients included in the study, 710 were female and 170 were male.

The mean PTH levels were 68.99, 56.10, 50.92 pg/ml when Vit D levels were <10 ng/dl, 10–20 ng/dl, 20–30 ng/dl and respectively and a statistically significant difference was found between PTH levels (P<0.0001).

When ROC analysis was performed, while Vit D level <5 ng/dl; PTH level was >71.25 pg/ml (sensitivity 45%, specificity 78%), while the Vit D level was <10 ng/dl; PTH level was>66.75 pg/ml (sensitivity 50%, specificity 77,4%), while Vit D level <20 ng/dl; PTH level was >61.1 pg/ml (sensitivity 40.3%, specificity 80.9%)

Conclusion: As the Vit D level decreases, the calcium level decreases statistically significantly while the parathormone level increases. Patients with Vit D deficiency have elevated PTH levels but PTH levels are still in the normal reference range. Prospective studies are needed to evaluate the effect of increased but still in a normal range PTH levels on bone with measurement of bone mineral density.