Abstract
Introduction: Individuals with polycystic ovary syndrome (PCOS) tend to exhibit insulin resistance and circulating levels of insulin higher than controls matched to obesity levels. The present study aimed to evaluate the hormonal alterations through body mass index (BMI) on the relationship between insulin, insulin resistance (IR), and thyroid hormone levels in PCOS.
Materials and Methods: This study is a retrospective clinical analysis study conducted at the department of gynecology and obstetrics between January 2019 and April 2020. PCOS participants were divided into two groups: 59 obese PCOS patients whose BMI value is equal and higher than 27kg/m2; 51 normal or overweight PCOS with BMI less than 27kg/m2.
Results: Age factor did not differ between groups (29.8±6 vs 31±7.2; p=0.345). In hormone tests, insulin (14.2±6.8 vs 14.8±8; p=0.688), Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) (3.1±1.4 vs 3.4±1.8; p=0.344), thyroxine (T4)(1.2±0.5 vs 1.2±0.4) and thyroid-stimulating hormone (TSH)(1.9±1.2 vs 1.8±0.9; p=0.848) levels did not differ for BMI groups (p>0.05). Because there was no difference in laboratory comparison for any parameter we analyzed, we could not perform multivariate analysis for further investigations in terms of BMI factor. In the hematological analysis, we did not see any significant alteration for groups.
Conclusion: We did not observe any difference between thyroid and IR in the patients who were grouped according to the BMI. PCOS and obesity may be directly related to hormonal interaction rather than adipose tissue.

Key words: Polycystic ovary syndrome, obesity, BMI, thyroid hormone