妊娠早期及中期铁储备与甲状腺功能的相关性

Relationship between body iron stores and maternal thyroid status in the first and second trimesters

目的:探讨碘适量地区妊娠早期及中期妇女体内铁储备与甲状腺功能的相关性。方法:210例常规产检的妊娠早期及中期妇女,行血清促甲状腺激素(TSH)、游离三碘甲状腺原氨酸(FT3)、游离甲状腺素(FT4)、总三碘甲状腺原氨酸(TT3)、总甲状腺素(TT4)、血清可溶性转铁蛋白受体(s TfR)、血清铁蛋白(SF)等测定。采用独立样本t检验、单因素方差分析及多元线性逐步回归分析评价FT4与总铁储备(TBI)及其他各因素相关情况。结果:妊娠早期妇女平均TBI为(9.05±4.04)mg/kg,妊娠中期妇女平均TBI为(8.02±4.18)mg/kg,两者无显著差异(P>0.05)。总体按TBI水平四分位分组,4组平均FT4分别为(13.76±2.03)、(14.69±1.78)、(15.40±1.61)、(16.16±2.87)pmol/L,随着TBI的升高,FT4逐渐增加,组间有显著差异(F=12.08,P<0.01);4组平均TT4分别为(127.85±22.56)、(134.89±22.61)、(136.82±28.16)、(142.65±32.89)nmol/L,随着TBI的升高,TT4逐渐增加,组间有显著差异(F=2.68,P<0.05)。Pearson分析显示FT4与BMI、TSH、s TfR呈负相关(r=-0.361、-0.286、-0.162,均P<0.05),与FT3、TT4、SF、TBI呈正相关(r=0.386、0.539、0.356、0.353,均P<0.01)。多元线性回归分析显示FT4与TBI呈独立正相关(β=0.281,t=4.124,P<0.01),FT4与BMI、TSH呈独立负相关(β=-0.265、-0.269,t=-3.929、-4.012,均P<0.01)。结论:妊娠早期及中期妇女FT4与TBI、TSH及BMI独立相关。

Objective： To investigate the relationship between body iron stores and maternal thyroid status in the first and second trimesters. Methods： A total of 210 pregnant women in the first and second trimesters were enrolled in a cross sectional study. Thyroid stimulating hormone（ TSH）,free triiodothyronine（ FT3）,free thyroxine（ FT4）,total triiodothyronine（ TT3）,total thyroxine（ TT4）,serum transferrin receptor（ s TfR）,and serum ferritin（ SF） were measured. The correlations between TBI and other parameters were analyzed respectively. Results： There was no significant difference between mean TBI in the first trimester[（ 9. 05 ± 4. 04） mg/kg] and that in the second trimester[（ 8. 02 ± 4. 18） mg/kg）,P〈0. 05]. TBI levels were classified into four groups. The mean FT4 were（ 13. 76 ± 2. 03）,（ 14. 69 ±1. 78）,（ 15. 40 ± 1. 61）,（ 16. 16 ± 2. 87） pmol/L,and with the increased level of TBI,FT4 increased（ F = 12. 08,P〈0. 01）. The mean TT4 were（ 127. 85 ± 22. 56）,（ 134. 89 ± 22. 61）,（ 136. 82 ±28. 16） and（ 142. 65 ± 32. 89） nmol/L,respectively. With the increasing of TBI level,TT4 increased（ F = 2. 68,P〈0. 05）. Pearson analysis showed that BMI,TSH,and s TfR were negatively correlated with FT4（ r =-0. 361,-0. 286,-0. 162,all P〈0. 05）,while FT3,TT4,SF,TBI were positively correlated with FT4（ r = 0. 386,0. 539,0. 356,0. 353,all P〈0. 01）. In the multiple linear step-downregression model with FT4 as the dependent variable,TBI was positively associated with FT4（ β = 0. 281,t = 4. 124,P〈0. 01）,while BMI and TSH were inversely associated with FT4（ β =-0. 265,-0. 269,t =-3. 929,-4. 012,all P〈0. 01）. Conclusion： FT4 of pregnant women was an independent factor associated with TBI,TSH and BMI in the first and second trimester.