Abstract：
OBJECTIVE: The purposes of this study were to assess the changes in body composition in patients who underwent thyroidectomy due to differentiated thyroid cancer (DTC) after radioactive iodine therapy (RAI) and short-term levothyroxine (LT4) supplementation and to explore the correlations between body composition distribution and corresponding blood indices.
METHODS: Fifty-seven thyroidectomized DTC patients were included. Serum was tested for several biochemical indices of thyroid function, lipids, and bone metabolism, and body composition parameters were measured via dual-energy X-ray absorptiometry before and 4-6 weeks after RAI and LT4 supplementation.
RESULTS: The body composition of DTC patients changed after RAI. Fat mass in all parts of the body decreased (range of relative change (RRC) -12.97--2.80%). Bone mineral content (BMC) increased throughout the body (relative change (RC) 12.12%), head (RC 36.23%), pelvis (RC 9.00%), and legs (RC 3.15%). Similarly, bone mineral density (BMD) increased in different regions (RRC 3.60-26.43%), except for the arms. Notably, lean mass in the arms (RC 4.30%) and legs (RC 3.67%) increased, while that in the head decreased (RC -2.75%), while total lean mass did not change at 4-6 weeks after LT4 supplementation. Furthermore, changes in fat distribution in the android region were related to the changes in total cholesterol (r = -0.390) and low-density lipoprotein cholesterol (r = -0.354), and changes in the BMC and BMD of the lumbar spine were positively associated with the changes in calcitonin (r = 0.302 and 0.325, respectively).
CONCLUSIONS: After RAI and short-term LT4 supplementation in DTC patients, body composition rapidly and positively changed and was characterized by decreased fat mass and increased BMC and BMD.
METHODS: Fifty-seven thyroidectomized DTC patients were included. Serum was tested for several biochemical indices of thyroid function, lipids, and bone metabolism, and body composition parameters were measured via dual-energy X-ray absorptiometry before and 4-6 weeks after RAI and LT4 supplementation.
RESULTS: The body composition of DTC patients changed after RAI. Fat mass in all parts of the body decreased (range of relative change (RRC) -12.97--2.80%). Bone mineral content (BMC) increased throughout the body (relative change (RC) 12.12%), head (RC 36.23%), pelvis (RC 9.00%), and legs (RC 3.15%). Similarly, bone mineral density (BMD) increased in different regions (RRC 3.60-26.43%), except for the arms. Notably, lean mass in the arms (RC 4.30%) and legs (RC 3.67%) increased, while that in the head decreased (RC -2.75%), while total lean mass did not change at 4-6 weeks after LT4 supplementation. Furthermore, changes in fat distribution in the android region were related to the changes in total cholesterol (r = -0.390) and low-density lipoprotein cholesterol (r = -0.354), and changes in the BMC and BMD of the lumbar spine were positively associated with the changes in calcitonin (r = 0.302 and 0.325, respectively).
CONCLUSIONS: After RAI and short-term LT4 supplementation in DTC patients, body composition rapidly and positively changed and was characterized by decreased fat mass and increased BMC and BMD.
摘要：
目的：本研究的目的是评估因分化型甲状腺癌(DTC)行甲状腺切除术的患者在接受放射性碘治疗(RAI)和短期补充左甲状腺素(LT4)后身体成分的变化，并探讨身体成分分布与相应血液指标的相关性。
方法：纳入57例甲状腺切除DTC患者。血清检测甲状腺功能的几个生化指标，脂质，和骨骼代谢，在补充RAI和LT4之前和之后4-6周，通过双能X射线吸收法测量身体成分参数。
结果：RAI后DTC患者的身体成分发生改变。身体所有部位的脂肪质量下降（相对变化范围（RRC）-12.97--2.80％）。全身骨矿物质含量（BMC）增加（相对变化（RC）12.12％），水头(RC36.23%)，骨盆（RC9.00%），和腿（RC3.15%）。同样，不同地区骨密度（BMD）增加（RRC3.60-26.43％），除了武器。值得注意的是,手臂(RC4.30%)和腿部(RC3.67%)的瘦体重增加，而头部下降(RC-2.75%)，而补充LT4后4-6周，总瘦体重没有变化。此外，在Android区域脂肪分布的变化与总胆固醇（r=-0.390）和低密度脂蛋白胆固醇（r=-0.354）的变化有关，腰椎BMC和BMD的变化与降钙素的变化呈正相关（分别为r=0.302和0.325）。
结论：DTC患者补充RAI和短期LT4后，身体成分迅速而积极地变化，其特征是脂肪量减少，BMC和BMD增加。
方法：纳入57例甲状腺切除DTC患者。血清检测甲状腺功能的几个生化指标，脂质，和骨骼代谢，在补充RAI和LT4之前和之后4-6周，通过双能X射线吸收法测量身体成分参数。
结果：RAI后DTC患者的身体成分发生改变。身体所有部位的脂肪质量下降（相对变化范围（RRC）-12.97--2.80％）。全身骨矿物质含量（BMC）增加（相对变化（RC）12.12％），水头(RC36.23%)，骨盆（RC9.00%），和腿（RC3.15%）。同样，不同地区骨密度（BMD）增加（RRC3.60-26.43％），除了武器。值得注意的是,手臂(RC4.30%)和腿部(RC3.67%)的瘦体重增加，而头部下降(RC-2.75%)，而补充LT4后4-6周，总瘦体重没有变化。此外，在Android区域脂肪分布的变化与总胆固醇（r=-0.390）和低密度脂蛋白胆固醇（r=-0.354）的变化有关，腰椎BMC和BMD的变化与降钙素的变化呈正相关（分别为r=0.302和0.325）。
结论：DTC患者补充RAI和短期LT4后，身体成分迅速而积极地变化，其特征是脂肪量减少，BMC和BMD增加。
