Thyroid stimulating hormone and free thyroxine are not associated with bone turnover markers (BTMs) or predictive of fracture risk in older men who have no known thyroid disease, according to new findings published in Clinical Endocrinology.
Subclinical thyroid dysfunction should therefore not be used as a biomarker for bone-related outcomes in older men, say the authors.
A few population-based studies have correlated thyroid hormones with BTMs and other papers have reported that BTMs were predictive of fracture risk in postmenopausal women and elderly men independent of bone mass density. However, study heterogeneity has limited the clinical utility of BTMs.
The goal of the current study was to clarify the relationship between thyroid stimulating hormone and free thyroxine with BTMs and incident hip fracture in a population of community dwelling healthy older men. The cohort included 3338 men without preexisting thyroid or bone disease. Of this group, 3117 had a normally functioning thyroid, 135 had subclinical hypothyroidism, and 86 had subclinical hyperthyroidism.
No significant differences in BTMs were observed between men with either subclinical hyperthyroidism or hypothyroidism when compared with men with normal thyroid function. Hip fracture occurred in 146 (4.7%) of those with normal thyroid function, 9 (4.4%) of those with subclinical hypothyroidism (hazard ratio 1.50; 95% CI, 0.73-3.07; P =.273), and 6 (7.0%) with subclinical hyperthyroidism (hazard ratio 1.62; 0.71-3.69; P =.254).
“Our study contributes to the literature regarding bone health in men, and suggests a neutral association of thyroid function with bone health in older men, in contrast to women,” the authors wrote.