Microvascular dysfunction in women with polycystic ovary syndrome

BACKGROUND: Polycystic ovary syndrome (PCOS) is associated with multiple cardiovascular risk factors and an increased prevalence of arterial dysfunction. However, microvascular dysfunction in PCOS has not been assessed. METHODS: Subjects comprised 12 women with PCOS and 12 age-matched controls with normal ovaries. Microvascular function was assessed by observing forearm skin microvascular erythrocyte flux responses, to cumulative iontophoretic doses of 1% (w/v) acetylcholine (ACh) and 1% (w/v) sodium nitroprusside (SNP), using laser Doppler imaging. RESULTS: Basal microvascular perfusion was comparable in PCOS and controls. The increase in skin microvascular perfusion in response to ACh was however generally blunted in PCOS women (P = 0.018). Peak ACh-induced erythrocyte flux was also less (p < 0.04) in PCOS women (125.1 6 21.7, i.e. 5.3-fold basal flux) than in controls (200.8 +/- 6 28.5, i.e. 8.3-fold basal flux). Analysis of covariance indicated this effect was unrelated to differences in body mass index or serum testosterone but serum insulin may be a weak confounder. No differences were noted between the PCOS and control groups in their response to SNP. CONCLUSION: Despite its limited sample size studied, this is the first demonstration that women with PCOS exhibit microvascular endothelial dysfunction, indicated by an inhibited vasodilatory response to ACh.