Endocrine Abstracts

JOINT1395

Background: Polycystic ovary syndrome (PCOS) is a complex disorder that is associated with an increased risk of cardiometabolic disorders. The metabolic dysfunction seen in PCOS has been tried to be explained by the presence of hypothyroidism, and it has been emphasized that cardiometabolic dysfunction becomes apparent when TSH is high. However, this relationship could not be demonstrated in euthyroid PCOS patients. In this context, we hypothesized that the metabolic dysfunctions in euthyroid PCOS patients could partly be explained by the presence of acquired mild thyroid hormone resistance (THR). We aimed to evaluate thyroid hormone sensitivity using thyroid hormone sensitivity indices and its relationship with homocysteine and PAI-1 levels in PCOS patients.

Methods: Patients aged 18-50 years with a diagnosis of PCOS were included in the PCOS group. Subgroup analysis of the patients was performed by grouping them as TSH<3.0 µIU/ml and TSH≥3.0 µIU/ml. Euthyroid subjects matched for age and body mass index (BMI) with the patient group, were included in the control group. TSH index (TSHI), thyrotropin thyroxine resistance index (TT4RI), thyroid feedback quarter-based index (TFQI) were calculated using TSH and fT4; TSHI(fT3), thyrotropin triiodothyronine resistance index (TT3RI), TFQI(fT3) were calculated using TSH and fT3; fT3/fT4 ratio was calculated using fT3 and sfT4. Statistical analysis was performed using the IBM SPSS 26.0 program. The level of statistical significance was accepted as P < 0.05.

Results: Although no statistically significant difference was found between the PCOS and control groups in terms of central and peripheral thyroid hormone sensitivity indices; fT3 and TFQI(fT3) were statistically signifcant between TSH≥3 PCOS and TSH≥3 control group. Positive correlations were found between TFQI value and HDL and total cholesterol levels and between TSHI, TSHI(fT3), TT3RI and TT4RI and waist circumference in the PCOS group, whereas negative correlations were found between TFQI(fT3) value and fasting glucose and between fT3/fT4 and fasting glucose, LDL and total cholesterol levels.

Conclusions: In our study, we thought that decreased thyroid hormone sensitivity may be one of the factors involved in the increased cardiometabolic risk in PCOS. More multicenter prospective studies with larger sample groups are needed to elucidate this relationship.