甲状腺功能正常和甲状腺功能减退患者游离三碘甲状腺原氨酸与游离甲状腺素比值与非酒精性脂肪性肝病的相关性研究

Correlation between FT3/FT4 and Non-alcoholic Fatty Liver Disease in Patients with Euthyroidism and Hypothyroidism

背景甲状腺激素参与机体的能量平衡、脂质代谢,被认为可能是导致非酒精性脂肪性肝病(NAFLD发生的潜在机制之一。近些年,甲状腺激素与NAFLD之间的关系已成为临床研究热点,但相关研究结论仍有很大的争议。目的探讨甲状腺功能正常(ET)和甲状腺功能减退(甲减)患者的甲状腺激素水平与NAFLD患病风险的相关性。方法选取2015年3月-2018年3月在南京中医药大学附属中西医结合医院内分泌代谢院区住院的患者382例。按照甲状腺功能水平分为:ET组268例,甲减组114例。按照有无NAFLD分为:NAFLD组166例,非NAFLD组216例。采集患者甲状腺激素指标,分析其与NAFLD的相关性,并绘制受试者工作特征(ROC)曲线。结果 268例ET患者中,合并NAFLD 113例,非NAFLD 155例。ET合并NAFLD者腰围(WC)、游离三碘甲状腺原氨酸(FT3)/游离甲状腺素(FT4)比值、三酰甘油(TC)、低密度脂蛋白胆固醇(LDL-C)、空腹胰岛素(FINS)、胰岛素抵抗指数(HOMA-IR)均高于ET非NAFLD者(P<0.05)。114例甲减患者中,合并NAFLD 53例,非NAFLD 61例。甲减合并NAFLD者WC、促甲状腺激素(TSH)、FT3/FT4比值、TC、LDL-C、FINS、HOMA-IR均高于甲减非NAFLD者(P<0.05)。多因素Logistic回归分析结果显示,WC〔OR=1.564,95%CI(1.125,2.174)〕、FT3/FT4比值〔OR=1.255,95%CI(1.067,1.477)〕、HOMA-IR〔OR=1.922,95%CI(1.194,3.095)〕是NAFLD发生的影响因素(P<0.05);WC〔OR=1.233,95%CI(1.056,1.439)〕、FT3/FT4比值〔OR=1.628,95%CI(1.381,1.919)〕、TC〔OR=1.168,95%CI(1.014,1.345)〕、HOMA-IR〔OR=1.502,95%CI(1.053,2.142)〕是甲减患者发生NAFLD的影响因素(P<0.05)。ROC曲线结果显示,在纳入所有患者中FT3/FT4比值预测NAFLD患病风险的ROC曲线下面积(AUC)为0.707〔95%CI(0.611,0.809)〕,最佳切点值为0.37,灵敏度为78.2%,特异度为58.5%。在甲减患者中FT3/FT4比值预测NAFLD患病风险的AUC=0.746〔95%CI(0.570,0.865)〕,最佳切点值为0.47,灵敏度为82.4%,特异度为61.2%。结论 WC、FT3/FT4比值、HOMA-IR是NAFLD患病的危险因素。在甲减合并NAFLD患者中,TC也是患病危险因素。

Background Thyroid hormone is involved in the body’s energy balance and lipid metabolism,which may be one of the potential mechanisms leading to the occurrence of non-alcoholic fatty liver disease(NAFLD).Recently,the correlation between thyroid hormone and NAFLD is becoming a focus of clinical research,but no clear conclusion has been made.Objective To investigate the correlation between thyroid hormone and NAFLD in patients with euthyroidism and hypothyroidism.Methods A total of 382 inpatients from the Endocrine and Diabetes Center,Affiliated Hospital of Integrated Traditional Chinese and Western Medicine,Nanjing University of Chinese Medicine were enrolled from March 2015 to March 2018,including 268 with euthyroidism,114 with hypothyroidism;166 with NAFLD,and 216 without.Thyroid hormone indices were collected,and their correlations with NAFLD were explored by using Logistic regression and ROC analysis.Results Of the 268 cases of euthyroidism,113 had NAFLD,and other 155 had not.NAFLD was associated with higher average levels of waist circumference(WC),total cholesterol(TC),low-density lipoprotein cholesterol(LDL-C),and fasting insulin(FINS),and higher average FT3/FT4 ratio,and homeostatic model assessment of insulin resistance index(HOMA-IR) in euthyroidism patients(P<0.05).Among the 114 cases of hypothyroidism,53 had NAFLD,and other 61 had not.NAFLD was associated with higher average levels of WC,TSH,TC,LDL-C,and FINS,and higher average FT3/FT4 ratio,and HOMA-IR in hypothyroidism patients(P<0.05).Multivariate Logistic regression analyses showed that WC〔OR=1.564,95%CI(1.125,2.174)〕,FT3/FT4 ratio〔OR=1.255,95%CI(1.067,1.477)〕and HOMA-IR〔OR=1.922,95%CI(1.194,3.095)〕 were influencing factors for NAFLD in all patients(P<0.05),and WC〔OR=1.233,95%CI(1.056,1.439)〕,FT3/FT4 ratio〔OR=1.628,95%CI(1.381,1.919)〕,TC〔OR=1.168,95%CI(1.014,1.345)〕and HOMA-IR〔OR=1.502,95%CI(1.053,2.142)〕 were influencing factors for NAFLD in patients with hypothyroidism(P<0.05).ROC curve analysis found that,the AUC of FT3/FT4 ratio was 0.707〔95%CI(0.611,0.809)〕 for predicting the risk of NAFLD in patients with euthyroidism and hypothyroidism,the determined optimal cut-off point was 0.37,with corresponding sensitivity of 78.2%,and specificity of 58.5%.The AUC of FT3/FT4 ratio was 0.746〔95%CI(0.570,0.865) 〕 for predicting the risk of NAFLD in patients with hypothyroidism,the determined optimal cut-off point was 0.47,with corresponding sensitivity of 82.4%,and specificity of 61.2%.Conclusion FT3/FT4 ratio,HOMA-IR and WC are the risk factors of NAFLD in those with euthyroidism and hypothyroidism.For those with hypothyroidism,TC is an additional independent risk factor for NAFLD.