Kim Mee Kyoung, Yun Kyung-Jin, Kim Min-Hee, Lim Dong-Jun, Kwon Hyuk-Sang, Song Ki-Ho, Kang Moo-Il, Baek Ki Hyun
Department of Internal Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
Department of Internal Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
Bone. 2015 Feb;71:101-5. doi: 10.1016/j.bone.2014.10.009. Epub 2014 Oct 23.
Studies on the effects of levothyroxine (LT4) therapy on bone and bone metabolism have yielded conflicting results. This 1-year prospective study examined whether LT4 in patients with well-differentiated thyroid carcinoma (DTC) is a risk factor for bone mass loss and the subsequent development of osteoporosis. We examined 93 patients with DTC over 12months after initiating LT4 therapy (early postoperative period). We examined another 33 patients on long-term LT4 therapy for DTC (late postoperative period). Dual energy X-ray absorptiometry was performed at baseline and after 1year. The mean bone losses during the early postoperative period in the lumbar spine, femoral neck, and total hip, calculated as the percentage change between levels at baseline and 12months, were -0.88, -1.3 and -0.81%, respectively. Bone loss was more evident in postmenopausal women (lumbar spine -2.1%, femoral neck -2.2%, and hip -2.1%; all P<0.05). We compared the changes in annual bone mineral density (BMD) in postmenopausal women according to calcium/vitamin D supplementation. Bone loss tended to be higher in the postmenopausal women receiving no supplementation. There was no decrease in BMD among patients during the late postoperative period. The mean bone loss was generally greater in the early than in the late postoperative group, and this was significant at the lumbar spine (P=0.041) and femoral neck (P=0.010). TSH-suppressive levothyroxine therapy accelerates bone loss, predominantly in postmenopausal women and exclusively during the early post-thyroidectomy period.
关于左甲状腺素（LT4）治疗对骨骼及骨代谢影响的研究结果相互矛盾。这项为期1年的前瞻性研究探讨了在分化型甲状腺癌（DTC）患者中，LT4是否为骨量丢失及后续骨质疏松发生的危险因素。我们在LT4治疗开始后的12个月内（术后早期）对93例DTC患者进行了检查。我们还检查了另外33例接受DTC长期LT4治疗的患者（术后晚期）。在基线和1年后进行双能X线吸收测定。术后早期腰椎、股骨颈和全髋部的平均骨丢失，以基线水平和12个月时水平的百分比变化计算，分别为-0.88%、-1.3%和-0.81%。绝经后女性的骨丢失更为明显（腰椎-2.1%，股骨颈-2.2%，髋部-2.1%；所有P<0.05）。我们比较了绝经后女性根据钙/维生素D补充情况的年度骨矿物质密度（BMD）变化。未补充的绝经后女性骨丢失往往更高。术后晚期患者的BMD没有下降。术后早期组的平均骨丢失总体上比晚期组更大，在腰椎（P=0.041）和股骨颈（P=0.010）处具有显著性差异。TSH抑制性左甲状腺素治疗会加速骨丢失，主要发生在绝经后女性中，且仅在甲状腺切除术后早期。
