Effect of adiponectin and sex steroid hormones on bone mineral density and bone formation markers in postmenopausal women with subclinical hyperthyroidism

Aim: The relationship between adiponectin and sex hormones with bone mineral density (BMD) and bone formation markers was investigated in postmenopausal women with subclinical hyperthyroidism (SCH). Methods: Seventy-five postmenopausal women were selected among the patients who participated in a health screening program in 2007. Thirty-seven control women with normal thyroid function were matched to 38 women with SCH by age, body mass index (BMI), and years since menopause (YSM). The associations between adiponectin and sex hormones with lumbar spine BMD and bone turnover markers were investigated. Results: Adiponectin, testosterone (T; total and free forms), and thyroid-stimulating hormone were significantly different between the women with SCH and euthyroid. After adjusting for age, BMI, and YSM, free T (r = 0.351; P = 0.029) and estradiol (E2; r = -0.368; P = 0.024) had significant associations with bone alkaline phosphatase (B-ALP). Total T (r = 0.388; P = 0.021) and E2 (r = -0.376; P = 0.026) had significant associations with osteocalcin. However, there were no significant associations between adiponectin and sex hormones with the BMD levels in the SCH subjects. Conclusion: There were correlations between sex hormones with B-ALP and osteocalcin, but no associations between adiponectin and sex hormones with the lumbar spine BMD in postmenopausal SCH patients.