Abstract
Background/Objectives: Hirsutism is excessive male-patterned hair in postpubertal women with multifactorial etiology and is an indicator of hyperandrogenism associated with polycystic ovary syndrome (PCOS). Indeed, it can be caused by the enhanced peripheral conversion of androgen precursors to testosterone, as in idiopathic hirsutism (IH). Moreover, hirsutism can be caused by hirsutism-related hyperandrogenic syndromes like non-classic congenital adrenal hyperplasia (NCAH) and idiopathic hyperandrogenism (IHA). Methods: In this study, we characterized a large cohort of Portuguese women referred for hirsutism and estimated the prevalence of PCOS, NCAH, IHA, and IH. The levels of androgens and gonadotropins and body mass index (BMI) were measured and compared with controls. The correlation between each variable was calculated. Results: In the cohort, we found a prevalence of PCOS of 56.2%, IH of 20.2%, IHA of 17.3%, and NCAH of 6.2%. Subjects with PCOS were the only ones showing a significant difference in BMI compared to the controls and had the lowest levels of sex hormone-binding globulin (SHBG). Those with NCAH were younger and more hirsute with higher levels of testosterone, among other androgens. Those with IH had lower luteinizing hormone (LH) and LH/follicle-stimulating hormone (FSH) ratios than those with PCOS. Those with IH had lower SHBG levels compared to the controls and a higher free androgen index (FAI). Those with IHA had higher androgens compared to those with IH, in particular, adrenal-derived androgens. Conclusions: The pathogenesis of hirsutism is complex, and the contributions of the pituitary gland, ovaries, adrenals, adipose tissue, and liver have to be ascertained to understand the clinical manifestations and delineate appropriate treatments. This study sheds new light on the fine hormonal regulation of these diseases.