Abstract: Background　Autoimmune thyroid disease and autoimmune diabetes often exist simultaneously.The frequency of thyroid autoantibody（TA） is higher in autoimmune diabetes patients.Objective　To investigate the association of anti-glutamic acid decarboxylase autoantibody（anti-GADA） and TA in Chinese physical examinees.Methods　The PUMCH Health Management database was searched for physical examinees who had their anti-GADA and TA tested from 2012 to 2015.The results of anti-GADA，thyroid stimulating hormone（TSH），thyroid peroxidase antibody（TPOAb） and thyroglobulin antibody（TgAb）and other data were collected.TA positive was defined as TPOAb positive or TgAb positive.Prevalence of anti-GADA was compared between TA positive and TA negative subjects，and also between diabetic and nondiabetic subjects.Clinical characteristics were compared among subjects with anti-GADA negative，anti-GADA low titer and anti-GADA high titer.Risk factors of TA positivity，TPOAb positivity and TgAb positivity were analyzed by multivariate Logistic regression.Results　There were 36 048 eligible participants totally，among whom 5 000 （13.9%） were TA positive〔3 321（9.2%） were TPOAb positive；3 552（9.9%） were TgAb positive〕 and 31 048（86.1%） were TA negative；2 600 （7.2%） met the diagnostic criteria of diabetes and 33 448 （92.8%） did not；185 （0.5%） were anti-GADA positive and 35 863 （99.5%） were anti-GADA negative.The prevalence of anti-GADA in TA positive subjects （n=51，1.0%） was significantly higher than that in TA negative subjects （n=134，0.4%）（χ2=29.203，P<0.001）.The prevalence of TA positivity was lower in diabetic subjects（n=280，10.8%）than that in nondiabetic ones （n=4 720，14.1%）（χ2=22.558，P<0.001）.The prevalence of anti-GADA is higher in diabetic subjects（n=31，1.2%）than that in nondiabetic ones （n=154，0.5%）（χ2=25.310，P<0.001）.The frequency of TA raised from anti-GADA negative group to anti-GADA low titer group to anti-GADA high titer group （13.8%，23.7%，39.1%，respectively，P<0.05）.In the multivariate Logistic regression，age〔OR=1.015，95%CI（1.012，1.018）〕，sex〔female：OR=3.483，95%CI（3.259，3.723）〕，diabetes〔yes：OR=0.837，95%CI（0.731，0.958）〕，anti-GADA〔low titer：OR=1.900，95%CI（1.266，2.853）；high titer：OR=4.259，95%CI（2.260，8.025）〕were risk factors for presence of TA（P<0.05）.Conclusion　Anti-GADA has a low prevalence in Chinese adult physical examinees.The presence of TA is associated with GADA positivity.

Key words: Diabetes mellitus, Thyroid diseases, Glutamic acid decarboxylase autoantibody, Thyroid autoantibody, Root cause analysis

摘要： 背景　自身免疫性甲状腺疾病和自身免疫性糖尿病常同时存在，而自身免疫性糖尿病患者继发甲状腺抗体（TA）阳性的风险升高。目的　研究我国体检人群中TA与抗谷氨酸脱羧酶抗体（GADA）的关系。方法　检索北京协和医院健康管理数据库，查询2012—2015年在北京协和医院进行健康体检并检测GADA和TA的人群，收集其体检资料和GADA、促甲状腺激素、甲状腺球蛋白抗体（TgAb）、甲状腺过氧化物酶抗体（TPOAb）水平，其中TPOAb、TgAb任一阳性记为TA阳性。比较TA阳性与阴性人群GADA阳性率，糖尿病与非糖尿病人群TA、GADA阳性率；分析GADA阴性、低滴度、高滴度人群的一般资料，探究体检人群TA阳性、TPOAb阳性、TgAb阳性的影响因素。结果　共36 048例体检人群符合纳入标准，其中TA阳性5 000例（13.9%）〔TPOAb阳性3 321例（9.2%）、TgAb阳性3 552例（9.9%）〕，TA阴性31 048例（86.1%）；符合糖尿病诊断2 600例（7.2%），不符合33 448例（92.8%）；GADA阳性185例（0.5%），GADA阴性35 863例（99.5%）。TA阳性人群中GADA阳性率〔51例（1.0%）〕高于TA阴性人群〔134例（0.4%）〕（χ2=29.203，P<0.001）。糖尿病人群中TA阳性率〔280例（10.8%）〕低于非糖尿病人群〔4 720例（14.1%）〕，GADA阳性率〔31例（1.2%）〕高于非糖尿病人群〔154例（0.5%）〕（χ2值分别为22.558、25.310，P<0.001）。GADA阴性、低滴度、高滴度体检人群中TA阳性率逐步递增（分别是13.8%、23.7%、39.1%）（P<0.05）。多因素Logistic回归分析结果显示：年龄〔OR=1.015，95%CI（1.012，1.018）〕、性别〔女：OR=3.483，95%CI（3.259，3.723）〕、糖尿病〔是：OR=0.837，95%CI（0.731，0.958）〕、GADA〔低滴度：OR=1.900，95%CI（1.266，2.853）；高滴度：OR=4.259，95%CI（2.260，8.025）〕是体检人群TA阳性的影响因素（P<0.05）。结论　我国体检人群中GADA阳性率较低，GADA阳性与TA阳性存在相关性。

关键词: 糖尿病, 甲状腺疾病, 抗谷氨酸脱羧酶抗体, 甲状腺自身抗体, 影响因素分析