Thyroid-stimulating antibody positivity may predict vertebral fracture risk in Graves’ disease
A cohort of postmenopausal Japanese women were more likely to sustain a vertebral fracture if they had thyroid-stimulating antibodies compared with women without the antibody, independent of age and severe osteoporosis status, according to findings published in Clinical Endocrinology.
“We need to consider the risk for fractures when treating postmenopausal women with Graves' disease,” Masakazu Notsu, MD, PhD, an assistant professor in the department of internal medicine at Shimane University Faculty of Medicine, Japan, told Healio. “Our data indicate the importance of appropriate evaluation of vertebral fractures for all postmenopausal Graves’ disease patients, especially in thyroid-stimulating antibody (TSAb)-positive patients.”
Takedani and colleagues analyzed data from 43 postmenopausal, Japanese women with Graves’ disease who visited Shimane University Hospital for hyperthyroidism treatment between 2004 and August 2018 (mean age, 64 years), as well as a control group of 86 age- and sex-matched healthy adults who underwent health screenings for osteoporosis at a community health center. All participants underwent bone mineral density measurements via DXA; lateral X-rays were obtained to evaluate vertebral fractures. Osteoporosis was diagnosed according to WHO criteria.
Researchers found that the prevalence of vertebral fractures (35% vs. 17%; P < .05), osteoporosis (63% vs. 33%; P < .01), and severe osteoporosis (40% vs. 17%; P < .01) was higher among women with Graves’ disease vs. controls.
In comparing women with Graves’ disease who did or did not sustain a vertebral fracture, researchers found no between-group differences in thyroid hormone levels or the positive ratio of thyroid antibodies; however, all women with Graves’ disease who sustained a vertebral fracture had TSAb positivity vs. 68% of women with Graves’ disease who did not sustain a vertebral fracture (P < .05).
In logistic regression analyses adjusted for age, Graves’ disease was associated with the presence of vertebral fractures among postmenopausal women (OR = 2.72; 95% CI, 1.13-6.54).
“These findings suggest that TSAb decreases bone mineral density and weakens bone strength via oxidative stress,” the researchers wrote. “However, the mechanism of how TSAb affects vertebral fractures is still unclear and further investigation would be required.”
The researchers wrote that the findings suggest that vertebral fracture evaluation should be recommended for women with Graves’ disease at the time of diagnosis.
“Future large-scale study would be required, and at the same time, how to prevent or treat is important,” Kai Takedani, MD, a clinical fellow in the department of internal medicine at Shimane University Faculty of Medicine, told Healio. – by Regina Schaffer
For more information:
Masakazu Notsu, MD, PhD, can be reached at Shimane University School of Medicine, 89-1 Enyacho, Izumo, Shimane 693-0021; email: email@example.com.
Disclosures: Notsu and Takedani report no relevant financial disclosures. Please see the study for all other authors’ relevant financial disclosures.