Predictive value of bone turnover markers and thyroid indicators for bone metabolism in GD patients after treatment

Abstract

Purpose: To investigate the relationship between bone turnover markers (BTMs) and thyroid indicators in Graves' disease (GD) and to further assess predictive value of changes in early stage retrospectively.

Methods: We studied 435 patients with GD and 113 healthy physical examiners retrospectively and followed up these two groups of patients after 6 months. We investigated the correlations between BTMs and other 15 observed factors, and analyzed the predictive value of FT₃ and FT₄ before and after treatment (FT₃-P/FT₃-A, FT₄-P/FT₄-A) on whether BTMs recovered.

Results: The levels of thyroid hormones and BTMs in GD group were significantly higher than those in control group (P < 0.05) and decreased after 6 months of treatment. FT3, W, Ca and ALP were independent factors in predicting the elevation of OST. Duration of disease, FT3, TSH and ALP were independent factors in predicting the elevation of P1NP. Age, duration of disease, TRAb and ALP were independent factors in predicting the elevation of CTX-1. The AUC of FT₃-P/FT₃-A and FT₄-P/FT₄-A for predicting OST recovery were 0.748 and 0.705 (P < 0.05), respectively, and the cut-off values were 0.51 and 0.595. There was no predictive value for P1NP and CTX-1 recovery (P > 0.05).

Conclusion: BTMs were abnormally elevated in GD and were significantly correlated with serum levels of FT3, FT4, TRAb, Ca, and ALP. FT₃ decreased more than 51% and FT₄ dropped more than 59.5% after 6 months of treatment were independent predictors for the recovery of BTMs in GD.

Keywords: CTX (C-terminal telopeptide of type 1 collagen); P1NP; bone turnover markers (BTMs); hyperthyroid; osteocalcin; procollagen type 1 N-terminal propeptide.