The Association Between Hypothyroidism And Systemic Lupus Erythematosus Related Organic Damage

Background:Systemic lupus erythematosus(SLE)is one of the systemic autoimmune diseases,which can usually lead to the damage of multiple organs.Hypothyroidism is a systemic low metabolic syndrome caused by the reduction of thyroid hormone synthesis/secretion or insufficient tissue utilization.Studies have found that hypothyroidism is the most frequent thyroid dysfunction in SLE patients and there is a certain correspondence between the severities of these two diseases.However,previous studies have several obvious drawbacks such as lack of standard control group,small sample size,and no detection of thyroid antibodies.Researchers hardly focused on the relationship between hypothyroidism and SLE-related organic damage.Purposes:1.To further confirm the prevalence of hypothyroidism in SLE patients and to clarify the clinical characteristics of SLE patients with hypothyroidism and the relationship between hypothyroidism and SLE-related organic damage,which can provide evidence for identifying risk factors of hypothyroidism in SLE.2.To analyze the relationship among SLE,hypothyroidism,thyroid autoantibodies,and SLErelated organic damage,and explore the causes of hypothyroidism in SLE patients,so as to provide some suggestions for the study about the potential mechanism of SLE with hypothyroidism.Results:1.The prevalence of clinical hypothyroidism(9.10%)and TgAb+TPOAb-(10.40%)in SLE patients were higher than those in the control group,but there was no difference in the positive rates of subclinical hypothyroidism,TgAb-TPOAb+and TgAb+TPOAb+.The prevalence of hypothyroidism was the highest in SLE patients aged 16-26 years(18.9%)and decreased with age addition.The prevalence of hypothyroidism with positive thyroid autoantibodies in SLE group was slightly higher than that in the control group(64.4%vs.51.5%,P=0.042),which was mainly due to TgAb;the prevalence of hypothyroidism with negative thyroid autoantibodies in SLE group was significantly higher than that in the control group(67.3%vs.47.8%,P<0.001).2.Compared with SLE-euthyroidism patients,SLE patients with hypothyroidism had higher levels of ESR,creatinine and 24-hour urinary protein levels,and higher prevalence of liver dysfunction,serositis,lupus nephritis,hemolytic anemia and cardiac insufficiency,and lower use of glucocorticoids/immunosuppressants.3.In multivariate Logistic regression analysis,liver abnormality(AOR,2.410,P=0.009),lupus nephritis(AOR,3.591,P<0.001)and cardiac insufficiency(AOR,8.410,P=0.008)were all independent risk factors for hypothyroidism in SLE,and glucocorticoid/immunosuppressive treatment(AOR,0.226,P<0.001)was an independent protective factor.Conclusion:Compared with the general population,the prevalence of hypothyroidism in SLE patients was higher and gradually decreased with age addition.The results suggested that young SLE patients combined with lupus nephritis,liver abnormality and cardiac insufficiency were at high risk for hypothyroidism.According to the results of this study,we speculated that thyroid might also be involved in SLE,and SLE might contribute to hypothyroidism.