Association between sensitivity to thyroid hormones and trabecular bone score in euthyroid individuals: a population-based cross-sectional study.

BACKGROUND

Thyroid hormone is a known pivotal factor that affects bone metabolism; however, whether bone microarchitecture is associated with thyroid hormone sensitivity is poorly understood. The trabecular bone score (TBS) serves as an essential indicator for assessing bone microarchitecture. This study aimed to investigate the relationship between sensitivity to thyroid hormones and TBS in euthyroid individuals.

METHODS

This cross-sectional study involved 3320 euthyroid participants from the National Health and Nutrition Examination Survey (NHANES) 2007-2008. Data, including thyroid function, TBS and other related parameters, were extracted and analyzed. The indices of thyroid hormone sensitivity, including the thyrotropin thyroxine resistance index (TT4RI), thyroid-stimulating hormone index (TSHI), thyroid feedback quantile-based index (TFQI) and parametric thyroid feedback quantile-based index (PTFQI), were calculated. Greater values of these indicators indicated a greater degree of impaired thyroid hormone sensitivity.

RESULTS

Impaired sensitivity to thyroid hormones was associated with degraded bone microarchitecture following adjustments for confounding variables (TT4RI: P = 0.005, TSHI: P = 0.008, TFQI: P = 0.003 and PTFQI: P = 0.006). The restricted cubic spline model demonstrated a positive relationship between TT4RI, TSHI, TFQI, PTFQI and degraded bone microarchitecture. Similar findings were observed in the analysis of subgroups stratified by age, sex, race, diabetes status, hypertension status and hyperuricemia status.

CONCLUSIONS

In euthyroid individuals, impaired sensitivity to thyroid hormones is associated with degraded bone microarchitecture. However, further studies are required to confirm this relationship.