Clinical Analysis Of Liver Function Abnormality Induced By Hyperthyroidism

Objective:In clinical practice, it has often been observed that a number of the newly diagnosed patients of Graves' disease have abnormal liver function. Although the patients' age, gender and the level of thyroid hormones have sparsely been reported to be associated with the degree of liver damage, at present there is no extensive study based on the research involving the thyroid antibodies and their correlation to liver function damage. This research principally observes the liver function damage in newly developed cases of Graves' disease(GD) and the related factors affecting it.Methods:We collected clinical data of 204 patients with incipient GD from January 2014 to June 2015 in Cangzhou City People's hospital where 235 normal people who had undergone the same physical examination as the patients of incipient GD were selected as the normal control group. The data were retrospectively analyzed in order to compare the incidence of liver damage in the incipient GD with that of the normal control groups. In the incipient GD group with liver damage, they were respectively divided into two groups according to the levels of FT3 and FT4, analysis if liver function related with thyroid hormone levels.In order to analyze the related factors of liver damage in incipient GD patients, they were respectively divided into positive and negative groups according to the presence or absence of TRAb, TPOAb and TGAb. A correlation analysis is carried out to ascertain the association of liver damage with the presence of antibodies. If so then whether and how the different levels of antibody titers along with that of FT3 and FT4 determined the degree of liver damage.Results:(1) The incidence of liver function damage in the hyperthyroid group is 52.94%, while that in the normal control group is 14.89%. Compared with the normal control group, the incipient GD group had a significantly higher incidence of liver damage(P<0.05).(2) In incipient GD patients the incidence of liver damage was slightly higher in females than the males(4.83:1). The age of onset of liver damage in men with incipient GD is higher than in women with a statistically significant difference(P<0.05). Both sexes were positive for TPOAb, TRAb and TGAb with high levels of FT3, FT4 and TSH but with no statistically significant difference(P>0.05).The positive rate of TRAb, TPOAb, TGAb and the difference of FT3, FT4, TSH levels in both sexes is no statistically significant difference(P>0.05).(3) Whether liver damage is a variable, dependent on the independent variables such as the thyroid hormone levels and its related antibodies, a logistic regression analysis shows that gender and FT3 is risk factor for liver damage.(4) Based on the liver function test that comprises of the different components such as the protein, transaminases and bilirubin, the incipient GD group is divided into GD group with liver damage and GD without liver damage. The level of protein, transaminases and and bilirubin(TB and DB) levels in the GD group with liver damage are higher than that with no liver damage with a statistically significant difference(P<0.05). But IB level revealed no difference between the two groups(P > 0.05).(5) It is observed in the antibody level profiling that the level of TRAb is of a significantly higher degree in the GD group with liver damage than in the one without(P < 0.05) while there was no significant difference(P > 0.05) in levels of TPOAb and TGAb between the two groups. In a correlation analysis between the serum thyroid function tests(FT3, FT4) and liver function indicators such as serum transaminases and bilirubins has shown a positive correlation(P < 0.05) whereas that with TP, ALB revealed a negative correlation(P < 0.05). However, there was no significant correlation with GLO(P > 0.05). On the other hand, serum TSH has shown negative correlation(P < 0.05) with bilirubin and transaminase indicators and that of a positive one(P < 0.05) with TP, ALB, Once again, there was no significant correlation with GLO(P > 0.05).(6) Incipient GD patients according to different FT4 level was divided into three groups: “22 < FT4 ? 66”; “66 < FT4 ?100” and “100 <FT4”.In these three groups, TB and IB differ in liver function indexes which is statistically significant(P < 0.05). After comparing the two it was further found that “66< FT4 ?100” had a higher level of TB and IB in liver function test than the “22<FT4?66” and “100<FT4” groups, There was no other differences between the two groups(P > 0.05).(7) Incipient GD patients according to difference in FT3 level was divided into three groups: “6.8< FT3?20.4”; “20.4 < FT3? 50” and “50<FT3”, In these three groups, ALT,GGT,AST,TB and IB in liver function indexes is statistically significant(P < 0.05).and other liver function indexes such as TP,ALB,GLO and DB of each group have not statistically significant difference(P < 0.05). After comparing the two it was further found that “50<FT3”had a higher level of ALT,GGT and AST in liver function test than the “20.4<FT3?50” and “20.4<FT3?50” groups is higher than the “6.8<FT3?20.4”, Moreover, TB,IB is highest in “20.4<FT3?50”,There was no other differences between the two groups(P > 0.05).(8) Incipient GD with liver damage is divided into TRAb positive and TRAb negative groups. In the TRAb positive group transaminases, bilirubin and TP indexes were significantly higher than in the TRAb negative group with a difference of statistical significance(P<0.05). However, GLO indexes were not significantly different(P>0.05) between the two groups.(9) In incipient GD group with TRAb positive was further divided into three groups according to the level of TRAb:“1.75<TRAb?17.5”; “17.5<TRAb?40”; and “40<TRAb” in order analyze whether the difference in TRAb levels has any effect on the extent of associated liver damage. It was found to be statistically insignificant(P > 0.05) indicating that the level of TRAb had no correlation with liver function damage indexes.(10) The incipient GD group with liver damage was divided TPOAb positive and TPOAb negative groups according to the presence or absence of the antibodies respectively. The liver function test of the two groups showed no significant difference(P > 0.05).(11)The incipient GD TPOAb positive group was further divided in three according to the degree of TPOAb level: “80<TPOAb?300”; “300<TPOAb?600”; and “600<TPOAb”. The results showed statistically insignificant(P > 0.05) difference indicating that the degree of TPOAb level had no correlation with liver function damage indexes.(12) In accordance with the data in all patients with incipient GD with TGAb positive were further divided into four groups: “1.7<TGAb?100”; “100<TGAb?1000”; “1000<TGAb?4000”; and “4000<TGAb” in order to compare how the different levels of TGAb are related to liver damage. The results revealed that the degree of TGAb level has no correlation with indexes of liver function damage and with no statistically significant difference(P>0.05).(13) TRAb showed a negative correlation(P<0.05) with serum TP, ALB whereas a positive one(P<0.05) with the DB, ALT and AST. However it showed no correlation(P > 0.05) with GLO, GGT,TB and IB. On the other hand TGAb had a negative correlation(P<0.05) with GGT but none with other liver function indexes(P > 0.05). Last of all,TPOAb showed no correlation with liver function indexes(P > 0.05).Conclusion:Therefore, it can be stated that liver damage is common in incipient GD patients with a morbidity of 52.9% which is significantly higher than that in normal control group with the incidence being higher in women than in men. The occurrence of liver damage is associated with gender, FT3, it showed no correlation with FT4, TSH and the titer levelof TRAb, TPOAb, TGAb. Moreover, it has been observed that the incipient GD group with liver damage FT3, FT4 and TSH along with the degree of TRAb were significantly higher than that of the incipient GD group without liver damage.