Endocrine Abstracts

Background: Polycystic ovary syndrome (PCOS) is according to the Rotterdam criteria defined as minimum two of: oligomenoré, hyperandrogenism and polycystic ovary. These criteria do not take into account PCOS’ association with the metabolic syndrome (MES) and ischaemic heart disease (IHD). Recently we grouped PCOS- patients into four phenotypes depending on normal/high BMI and insulin resistance (IR). We demonstrated that PCOS-patients with high BMI and increased IR had a metabolic phenotype with elevated hsCRP, PAI-1 and thrombin generation time, which are all associated with MES and IHD. Vasopressin mediates water retention, vasoconstriction and ATCH-secreation in healthy. Copeptin is part of the precursor vasopressin peptide and released during processing. It is stable and easy to measure, making it a surrogate marker for vasopressin. Elevated levels of copeptin are associated with IHD, diabetes, microalbinuria and it is hypothesized to be due to central stimulation coursed by low-grade inflammation. Our aim was to study copeptin in PCOS.

Methods: Cross sectional observation study. 98 women with PCOS, age 18–54, no medication for 6 weeks prior, no diabetes. Copeptin was measured using commercial sandwich immunoassay, BRAHMS.

Results: Copeptin was divided into tertiles and increasing levels were associated with increasing levels of C-peptide, free testosterone and PAI-1. Univariate linear regression analysis showed that age (β=−0.21; P=0.036), C-peptide (β=0.34; P=0.001), HOMA (insulin) (β=0.21; P=0.041), free testosterone (β=0.25; P=0.012), SHBG (β=−0.27; P=0.007) and PAI–1 (β=0.27; P=0.008) correlate with concentrations of copeptin. Multivariate linear regression analysis showed that C-peptide and free testosterone were independently associated. No correlation was found regarding the four phenotypes, BMI, android fat, BP, hsCRP, creatinin, hirsutism score, ovary volume, menstruation cycle or cholesterol.

Conclusion: Copeptin levels in these PCOS-patients demonstrate a association with hyperandrogenism (free testosterone), IR (C-peptide) and low-grade inflammation (PAI-1). The data support the emerging opinion that the Rotterdam criteria do not fully describe PCOS.