Gender impact on the correlation between thyroid function and serum lipids in patients with differentiated thyroid cancer.

The present study aimed to explore the association between thyroid stimulating hormone (TSH) and serum lipids in patients with differentiated thyroid cancer (DTC), with a focus on the risk of hyperlipidemia between different genders. The study included 352 DTC patients who were ready to receive I-131 therapy as well as 352 matched normal controls. In the DTC group, 157 patients were monitored for TSH and lipid parameters prior to and after 1 month of thyroxine therapy. Results were analyzed using t-tests, Pearson bivariate correlation and binary logistic regression analyses. All participants were divided into 3 subgroups according to TSH levels: Subgroup 1 (normal TSH level), subgroup 2 (TSH between 5 and 30 µIU/ml), and subgroup 3 (TSH >30 µIU/ml). Serum total cholesterol (TC), triglycerides (TG), and low-density lipoprotein-cholesterol (LDL-C) levels were significantly higher in the DTC group than in the control group. The levels of these parameters decreased after thyroxine therapy and significant positive correlations were observed between TSH and TC, and TG and LDL-C in both genders. Binary logistic regression demonstrated that female DTC patients had higher risks of developing hyperlipidemia than male patients, and these risks increased when TSH increased. For example, the odds ratios (ORs) of high TC in subgroup 2 were 3.30 in males and 4.60 in females, respectively. However, in subgroup 3, the ORs were 9.40 in males and 13.12 in females, respectively. The results of the present study showed that after thyroidectomy, the risk of dyslipidemia markedly increased in DTC patients. More importantly, female patients had a higher risk than male patients.