Akademik Veri Yönetim Sistemi
Klinik Gelisim, cilt.7, sa.5, ss.3050-3055, 1994 (Scopus)
In this study we investigated the effect of exogenous subclinical hyperthyroidism on bone turnover by measuring serum osteocalcin which is sensitive marker of osteoblastic activity. Serum osteocalcin and TSH were measured in 86 premenopausal women (20-45 years old) with nontoxic diffuse and nodular goiter (NDNG) who had been taking L-thyroxine for 1-10 years as suppressive therapy. Patients who had any disease and were on any therapy that could effect bone mineral metabolism were excluded from the study. Patients were divided into 3 groups according to their ages. Because serum osteocalcin level changes with ages. There were 30 patients in group 1 (aged 20-29 yr), 34 patients in group 2 (aged 30-39 yr) and 22 patients in group 3 (40-45 yr). In each age group serum osteocalcin levels were significantly higher in subgroups with suppressed TSH levels compared with subgroups without TSH suppression (p<0.001). When all the patients were combined, negative correlation was found between serum osteocalcin and TSH levels (r=0.69), p<0.001). No correlation was found between serum osteocalcin and the duration of therapy with L-thyroxine in patients without reduced TSH levels (r=0.084, p=0.5). These results suggest that exogenous subclinical hyperthyroidism due to suppressive therapy in NDNG patients increases bone turnover in correlation with the duration of treatment adn such patient are at risk of developing premature osteoporosis. Therefore to avoid long term potential risks, suppressive thearpy must not be prolonged more than necessary. If other risk factors for osteoporosis exist, the benefit-risk ratio must be taken into consideration and other choices either observation or surgical therapy must be considered. Patients on long term suppressive thearapy must be periodically examined for osteoporosis by mineral density and biochemical bone turnover marker measurements.