Severe endothelial dysfunction in young women with polycystic ovary syndrome is only partially explained by known cardiovascular risk factors.

OBJECTIVE: We aimed to assess whether metabolic abnormalities can explain endothelial dysfunction and associated cardiovascular disease risk (CVDr) in polycystic ovary syndrome (PCOS). Endothelial function, a recognized composite marker of CVDr, may be reduced in PCOS and can be precisely and noninvasively assessed by cardiovascular magnetic resonance (CMR). PATIENTS: Fourteen women with anovulatory PCOS (age [mean +/- SD] 33 +/- 4 years) and 13 controls (age: 33 +/- 6 years) with similar body mass index and regular menses.
METHODS: Endothelium-dependent (flow-mediated dilatation - FMD) and -independent (glyceryl trinitrate - GTN) changes in the brachial artery area were measured using CMR in women with PCOS and controls. Arterial function was assessed twice, in the early follicular phase and mid cycle in controls and after an interval of 2 weeks in PCOS subjects. Fasting lipids, glucose, insulin and sex hormones were measured at the first visit.
RESULTS: FMD was greatly reduced in women with PCOS compared to controls (-1%vs 5% and 2%vs 12%, P < 0.01) without differences in GTN responses. Risk factors were more prevalent in PCOS women and displayed significant linear relationships with FMD. PCOS status was the strongest predictor of FMD. Linear regression between PCOS and FMD remained significant after correction for all CVD risk markers linked to the metabolic syndrome.
CONCLUSION: PCOS is associated with changes in CVD risk markers and pronounced endothelial dysfunction. However endothelial dysfunction with PCOS is only partly explained by recognized CVD risk markers.