BONE MASS IN FEMALES WITH DIFFERENT THYROID-DISORDERS - INFLUENCE OF MENOPAUSAL STATUS

The aim of this study was to evaluate the effect of thyroid functional state on cortical and trabecular bone mineral density (BMD) (g/cm2) i n premenopausal and postmenopausal women. Control subjects were used a s a reference population to calculate Z-scores from patient data. In p atients with active hyperthyroidism, BMD was reduced in lumbar spine ( LS; P < 0.01), femoral neck (FN; P < 0.01) and Ward triangle (WT; P < 0.0001) in comparison with reference standards. In premenopausal women treated in the past for hyperthyroidism or treated at the time of stu dy with L-thyroxine in non-TSH-suppressive doses, there was no signifi cant decrease in BMD. In postmenopausal women with hyperthyroidism in remission, we found a significant decrease in BMD in LS (P < 0.01), FN (P < 0.05) and WT (P < 0.0001). In postmenopausal women treated with L-thyroxine (L-T4), there was a significant decrease in BMD in LS (P < 0.01) and WT (P < 0.01). There was a significant negative correlation between the cumulative dose of L-T4 and BMD in FN (r = -0.688, P < 0. 05) and WT (r = -0.657, P < 0.05) in postmenopausal women. Our finding s suggest that the deleterious effects of thyroid hormones on BMD are accentuated in areas consisting predominantly of trabecular bone, e.g. , the LS and WT. Postmenopausal women subjected to excess thyroid horm one represent a population at greater risk for osteoporosis.