Changes and Correlation Analysis of Blood Lipids in Patients with Differentiated Thyroid Cancer After Discontinuation of Levothyroxine Tablets

He Yijun; Chen Weina; Jia Jing

doi:10.3969/j.issn.1004-5775.2025.07.002

Abstract：Objective:To statistically analyze the levels of blood lipids and thyroid hormones in patients with differentiated thyroid cancer(DTC)before surgery and after discontinuation of thyroxine(surgery+131 Ⅰ treatment+T4 treatment),analyze their changes and correlation,and propose improvement measures.Methods:A total of 345 patients with differentiated thyroid cancer who were re-examined in the First Affiliated Hospital of Zhengzhou University from November 2022 to November 2023 were selected as the study objects.Levothyroxine sodium tablets should be stopped for about 4 weeks(25～31 days)before review.The serum free triiodoformionine(FT3),serum free thyroxine(FT4),thyrotropin(TSH),total cholesterol(TC),triglyceride(TG),high density lipoprotein(HDL),low density lipoprotein(LDL),and blood pressure of the patients were tested.The above laboratory results before surgery were analyzed and discussed.Results:There was negative correlation between LDL and FT4 in patients before surgery(rs=-0.120,P＜0.05),and positive correlation between systolic blood pressure and FT3(rs=0.109,P＜0.05).There was no correlation between other indicators of blood lipid levels and thyroid function(P＞0.05).When taking levothyroxine sodium tablets for about 4 weeks(25～31 days)for follow-up,the patient's FT3 and FT4 levels decreased compared to before surgery.TSH levels,total cholesterol(TC),triglycerides(TG),high-density lipoprotein(HDL)and low density lipoprotein(LDL)levels were significantly elevated compared to preoperative levels(t=-35.832,-13.816,-10.974,-32.214,-7.226,-16.827,-12.415;P＜0.05).There was negative correlation between TC,TG,and FT4(P＜0.05),while TC,TG,HDL,LDL,SP were positively correlated with TSH(P＜0.05).Conclusion:In patients with differentiated thyroid cancer,after discontinuing levothyroxine sodium tablets for about 4 weeks,thyroid hormone levels decrease,and blood lipid levels increase.During this period,patients should be guided to consume a low-fat,low iodine and high vitamin diet;combine with medical care;improve their blood lipid levels;and reduce the risk of complications.