甲状腺功能减退对妊娠妇女骨代谢及骨密度的影响

目的 探讨甲状腺功能减退(甲减)对妊娠妇女骨代谢及骨密度(BMD)的影响.方法 选取82例妊娠中期甲减患者作为甲减组,同期50例妊娠中期产检正常的妇女作为对照组.采用超声骨密度仪测定并比较跟骨部位的BMD值,同时检测并比较两组血钙(Ca)、血磷(P)、碱性磷酸酶(ALP)、总Ⅰ型前胶原氨基端延长肽(TPⅠNP)、Ⅰ型胶原羧基端肽 β特殊序列(CTX-β)等骨代谢指标,促甲状腺激素(TSH)、游离甲状腺素(FT4)、游离三碘甲状腺原氨酸(FT3)等甲状腺功能指标.采用Pearson线性相关分析各指标之间的相关性.结果 甲减组跟骨BMD值较对照组显著降低(1.08±0.16比0.96±0.15)g·cm-2],骨质疏松的发生率(6.0%比18.3%)则显著升高(t=4.347,P=0.000;χ2=3.985,P=0.046).与对照组比较,甲减组血清Ca(2.22±0.14比2.54±0.16)mmol·L-1]、ALP(63.92±10.32比69.53±11.24)U·L-1]明显降低,P(1.43±0.23比1.18±0.17)mmol·L-1]、TPⅠNP(56.32±12.52比47.06±11.86)μg·L-1]、CTX-β(0.32±0.12比0.21±0.07)pg·L-1]明显升高(t=12.062,P=0.000;t=7.148,P=0.000;t=2.929,P=0.004;t=4.204,P=0.000;t=6.650,P=0.000).TSH与跟骨BMD值及Ca、ALP呈负相关(r=-0.58,-0.51,-0.45,P<0.05),与TPⅠNP、CTX-β呈正相关(r=0.48,0.44,P<0.05),FT3、FT4与跟骨BMD值、Ca、ALP呈正相关(r=0.43,0.40,0.41;0.51,0.44,0.48,P<0.05),与TPⅠNP、CTX-β呈负相关(r=-0.47,-0.50;-0.46,-0.51,P<0.05).结论 甲减可影响妊娠妇女骨代谢,降低骨密度,导致骨量丢失、骨折风险增加,临床上应加强对妊娠妇女的甲状腺功能筛查.

Effectsof hypothyroidism on bone mineral density and bone metabolism in pregnant women

Eighty-two mid-pregnancy hypothyroidism patients were selected as hypothyroidism group ,and 50 cases with normal mid-pregnancy examination results during the same period were selected as control group .BMD of calcaneus was measured and compared by ultrasound bone sonometer ,and bone metabolism indicators including blood calcium (Ca),serum phosphorus (P),alkaline phosphatase (ALP),total type I procollagen amino-terminal extension peptides (TPⅠNP),βspecial sequence of type I collagen carboxyl terminal peptide (CTX-β),and thyroid function indicators including thyroid function such as thyroid stimulating hormone (TSH),free thyroxine ( FT4),free triiodothyronine (FT3) in both groups were detected.Pearson correlation analysis was used to analyze the relationship among these indexes .Results Compared with control group,BMD values of calcaneus in hypothyroidism group were significantly reduced (1.08 ±0.16 vs 0.96 ±0.15) g· cm-2 ],the incidence of osteoporosis was significantly increased (6.0%vs 18.3%)(t =4.347,P =0.000;χ2 =3.985,P =0.046).Compared with control group,the level of Ca (2.22 ±0.14 vs 2.54 ±0.16) mmol· L-1 ],ALP (63.92 ±10.32 vs 69.53 ±11.24) U· L-1 ] were significantly reduced,levels of P (1.43 ±0.23 vs 1.18±0.17) mmol· L-1 ],TPⅠNP (56.32 ±12.52 vs 47.06 ±11.86) μg · L-1 ],CTX-β(0.32 ±0.12 vs 0.21 ±0.07) pg· L-1 ]in hypothyroidism group were significantly increased (t =12.062,P =0.000;t =7.148,P =0.000;t =2.929,P =0.004;t =4.204,P =0.000;t =6.650,P =0.000).Pearson correlation analysis showed that TSH was negatively correlated with calcaneal BMD values ,Ca and ALP(r =-0.58, -0.51, -0.45,P <0.05),positively correlated with TPⅠNP and CTX-β(r =0.48,0.44,P <0.05).F3,F4 were positively correlated with calcaneal BMD values ,Ca and ALP (r =0.43,0.40,0.41;0.51,0.44,0.48,P <0.05),negatively correlated with TPⅠNP and CTX-β(r =-0.47, -0.50; -0.46, -0.51,P <0.05).Conclusions Hypothyroidism has influence on the bone metabolism of pregnant women ,which can lead to bone loss and increase the risk of fractures .Therefore,screening of thyroid function for pregnant women should be strengthened in clinic .