Normal TSH Levels May Decrease Postmenopausal Osteoporosis Risk

Normal thyroid-stimulating hormone (TSH) levels that are closer to a high range are associated with a decreased risk of osteoporosis in women who are postmenopausal, according to a study published in BMC Women’s Health.

Researchers performed a key word search of 6 databases and included 19 observational studies (participants, 23,960) in the investigation to explore correlations between TSH and bone mineral density among women with normal thyroid functioning who were postmenopausal. The team included articles written in English or Chinese, and excluded review articles and studies with incomplete data from the meta-analysis.

TSH was positively correlated with bone mineral density (Fisher’ Z=0.16; 95% CI, 0.00-0.32), according to the report. After adjusting for confounding factors, which included age, body mass index (BMI), and bone mineral density, multivariate logistic regression revealed individuals with low TSH levels were almost twice as likely to have osteoporosis compared with individuals who had high TSH levels (odds ratio [OR], 1.76; 95% CI, 1.27-2.45). Additionally, osteoporosis risk remained relatively similar in participants with low TSH who were taking anti osteoporosis drugs compared with individuals who did not use the drugs (OR, 1.84; 95% CI, 1.05-3.22; P =.03 vs OR, 1.74; 95% CI, 1.08-2.82; P =.02).

The report shows a dose-response relationship at TSH levels of 2.5mIU/L — the risk of osteoporosis gradually decreased with TSH levels greater than this value.

“The dose-response relationship showed that when TSH was above 2.5mIu/L, the incidence of osteoporosis tended to be decreased,” the study authors explain. “These results provided a theoretical basis for the prevention and treatment of osteoporosis in postmenopausal women.”

The strict inclusion of cross-sectional surveys in the meta-analysis and 1-time measurements of TSH and bone mineral density among study participants are acknowledged limitations to the research.