Free androgen index (FAI)’s relations with oxidative stress and insulin resistance in polycystic ovary syndrome

Abstract This study aimed to determine the levels of the free androgen index (FAI) and its association with oxidative stress and insulin resistance (IR) in patients with polycystic ovary syndrome (PCOS). This cross-sectional study was performed on 160 women aged 18–45 years, visiting gynecology clinics of Urmia in northwestern Iran during 2020–2021 who were diagnosed with PCOS and exhibited one of the four phenotypes of PCOS. All the participants underwent clinical examinations, paraclinical tests, and ultrasounds. FAI cut-off point was considered to be 5%. The significance level was set at < 0.05. Among the 160 participants, the prevalence of the four phenotypes was as follows: phenotype A: 51.9%, phenotype B: 23.1%, phenotype C: 13.1%, and phenotype D: 11.9%. High FAI was detected in 30 participants (18.75%). Additionally, It was found that phenotype C had the highest FAI levels among the PCOS phenotypes, with a significant difference between phenotypes A and C ( p value = 0.03). IR was observed in 119 (74.4%) of the participants, and the median (interquartile range: IQR) of malondialdehyde (MDA) levels among the participants was 0.64 (0.86) μM/L. In linear regression, the PCOS phenotype (standard beta = 0.198, p -value = 0.008), follicle-stimulating hormone (FSH) levels (standard beta = 0.213, p -value = 0.004), and MDA levels (standard beta = 0.266, p -value < 0.001) were significantly related to the FAI level, but the homeostatic model assessment for insulin resistance (HOMA-IR) was not statistically associated with FAI. Thus, in this study, PCOS phenotypes and MDA levels (an indicator of stress oxidative) were significantly related to FAI, but HOMA-IR (the indicator of IR) was not associated with it.