The serum osteocalcin levels in patients with thyroid diseases

The mechanism of bone, calcium, phosphorus and proteins abnormalities observed in hyperthyroidism is rather complex and as yet not wholly understood. Increased serum osteocalcin was recently reported in hyperthyroid patients and its decrease after 4-8 months of treatment. Osteocalcin was measured by RIA in the sera of 211 women and 18 men with thyroid diseases. The patients were divided into 3 groups according to diagnosis: I. polynodular goitre and subacute thyroiditis (59 women, 5 men); II. Graves' disease (70 women, 3 men) and III. thyroid cancer, after treatment by surgery and 131I (82 women, 10 men). The osteocalcin levels in the sera of these patients were: 2.97 +/- 2.63 ng/ml (mean +/- SD) for the women and 3.56 +/- 2.10 ng/ml for the men in the 1st group; 16.31 +/- 11.34 ng/ml for the women and 12.75 +/- 6.09 ng/ml for the man in the IInd group and, 1.01 +/- 0.60 ng/ml for the women and 0.78 +/- 0.46 ng/ml for the men in the IIIrd group. No differences were found between the osteocalcin concentrations in the hyperthyroid female patients treated with antithyroid drugs (no = 58) and the non-treated hyperthyroid women (no = 12): 16.22 +/- 11.40 ng/ml vs 16.74 +/- +/- 11.53 ng/ml. These data suggest that bone resorption stimulated by endogenous thyroid-hormones is a rather resistant processus, persisting even after 6-8 mos of associated anti-thyroid therapy. Further are analyzed the possible causes of the subnormal osteocalcin levels observed in patients with thyroid cancer treated by surgery and radioisotope, whose suppression therapy was discontinued 2-3 weeks before blood sampling.(ABSTRACT TRUNCATED AT 250 WORDS)