The Plasma Cortisol Level Changed In Patients With Different Condition Of Hyperthyroidism Before And After Treatment

Objective: To better understand the relationship between hyperthyroidism and the levels of plasma cortisol and ACTH,patients with hyperthyroidism were grouped based on their clinical conditions.Their cortisol and ACTH levels were assessed before and after treatment.Method: The subjects were 57 patients with hyperthyroidism treated in the First Affiliated Hospital of Guangxi Medical University from April 2016 to Feb.2017.The patients were divided into three groups based on their conditions:mild,moderate and severe group.Correspondingly,the patients were treated with Anti-thyroid drugs at low dose(MMI 15mg/d or PTU 150 mg/d),middle dose(MMI 20mg/d or PTU 200 mg/d)or conventional dose(MMI 30mg/d or PTU 300 mg/d).Patients’ conditions were accessed every 30 days,and lab tests included 8 am blood cortisol and ACTH level,thyroid function,liver function and blood routine test.Results: 1.FT3,FT4 levels: After treatment,the FT3 and FT4 levels of patients in all three groups were significantly lower(p<0.01)than those before treatment,at different time points.After 30-day treatment,the FT3 and FT4 levels were significantly reduced in all three groups(p<0.01).After 60-daytreatment,the FT3 and FT4 levels of patients showed no significant difference compared with healthy controls(p>0.05).After 90-day treatment,the FT3 and FT4 in patients were reduced to normal level.2.8am Cortisol level:(A)Before treatment,the 8am Cortisol level between the three groups were significantly different(310.1±115.9nmol/l vs264.4±79.2nmol/l vs 252.3±64.6nmol/l;p<0.01)and the difference became non-significant after 30-day,60-day and 120-day treatment.(B)For patients from the mild group,there was no significant difference before and after treatment(p>0.05).For the moderate group,the 8am cortisol levels were significantly increased after 120-day treatment(326.7±86.0nmol/l vs264.4±79.2nmol/l,p < 0.05).For the severe group,the 8am cortisol levels were significant higher after 60-day,90-day and 120-day treatment(p<0.05).(C)Before treatment,the 8am cortisol levels from moderate group were significantly lower compared with control group(264.4±79.2nmol/l vs333.2±84.4 nmol/l,p < 0.05)and the difference was gone after 120-day treatment.The 8am cortisol levels in the severe group were also significantly lower before treatment(252.3±64.6nmol/l vs 333.2±84.4 nmol/l,p<0.01),and the difference was gone after 30-day treatment.Specifically,three patients from moderate groups(~21%)and 6 patients(~26%)from severe groups presented lower cortisol level.3.8am ACTH level: Compared with healthy control,there is no significant difference for 8am ACTH from all the three groups along the treatment course(p> 0.05).After treatment,the 8am ACTH level in the sever group were all significantly lower than that before.4.The correlation between 8am cortisol and FT3,FT4 before and after treatment.The FT3 and FT4 levels in the mild group were negatively correlated with blood cortisol level(r=-0.294/-0.277,p=0.025/0.035).The FT3 and FT4 in the severe group were also negatively correlated with blood cortisol level(r=-0.322/-0.348,p=0.010/0.003).The correlation in the moderate group was not significant(r=-0.305/-0.327,p=0.257/0.209).Conclusion: 1.The clinical condition is a major factor contributing to the reduction of plasma cortisol in patients with hyperthyroidism.Before treatment,24% patients in moderate/severe groups have a risk for adrenal insufficiency.But patients from mild group showed normal 8am cortisol level.After anti-thyroid drug treatment,the 8am cortisol level in patients gradually went back to normal,which was consistent with the symptom relieves.2.For patients with moderate to severe conditions,the HPA functions were suppressed,and pituitary secretions of ACTH were reduced.When the hyperthyroidism conditions got relieved,there may be a transient increase in the cortisol levels.