Effects of Insulin Resistance on Myocardial Blood Flow and Arterial Peripheral Circulation in Patients with Polycystic Ovary Syndrome.

OBJECTIVE: Polycystic ovary syndrome (PCOS) is associated with increased risk for cardiovascular disease. We sought to evaluate the effects of insulin resistance (IR) on myocardial microcirculation and peripheral artery function in patients with PCOS. METHODS: We studied 55 women (28 with PCOS without IR, 18 with PCOS and IR and 11 normal controls) who underwent laboratorial analysis, high-resolution vascular ultrasound and real time myocardial contrast echocardiography (RTMCE). Intima-media thickness (IMT) and brachial artery flow-mediated dilation (FMD) were evaluated by vascular ultrasound. The replenishment velocity (ß), plateau of acoustic intensity (A) and myocardial blood flow reserve (MBFR) were determined by quantitative dipyridamole stress RTMCE. RESULTS: ß reserve in group PCOS + IR was lower than control (2.34 ± 0.55 vs. 3.60 ± 0.6; P < 0.001) and than PCOS without IR (2.34 ± 0.55 vs. 3.17 ± 0.65; P < 0.001). MBFR in patients with PCOS without IR did not differ from those of control (4.59 ± 1.59 vs. 5.30 ± 1.64; P = 0.22) or from patients with PCOS + IR (4.59 ± 1.59 vs. 3.70 ± 1.47; P = 0.07). When comparing with control group, patients with PCOS + IR had lower MBFR (5.30 ± 1.64 vs. 3.70 ± 1.47; P = 0.01). No significant differences were found between control, PCOS without IR and PCOS + IR for FMD (0.18 ± 0.05, 0.15 ± 0.04 and 0.13 ± 0.07; P =NS) or IMT (0.48 ± 0.05, 0.47 ± 0.05 and 0.49 ± 0.07; P = NS). CONCLUSION: Women with PCOS and IR had depressed ß and MBFR as demonstrated by quantitative RTMCE, but no alteration in endothelial dysfunction or IMT. PCOS without IR showed isolated depression in ß reserve, probably an earlier marker of myocardial flow abnormality.

Myeloperoxidases and polycystic ovary syndrome.

New biological markers are emerging trying to identify earlier cardiovascular high risk subjects. Myeloperoxidases have been involved in the role of atherosclerosis process, by the beginning of the endothelial dysfunction up to the plaque rupture and clinical manifestation, and it has been demonstrated that this enzyme has also a prognostic value. We aimed to assess myeloperoxidases levels in patients with polycystic ovary syndrome (PCOS) with insulin resistance (IR), considering that these women represent a high risk group for cardiovascular disease. We developed a transversal study, comprising 26 patients with PCOS and IR and 30 controls (PCOS without IR). IR was considered with HOMA-IR ≥3.0. IR absence was considered when HOMA-IR <3.0, triglycerides <200, BMI <28.7, and BMI<27.8 in patients with familial history of type 2 diabetes. All patients went through anamnesis, physical examination, transvaginal ultrasound, and blood samples. IR PCOS patients had higher levels of myeloperoxidase (22.3 × 18.1, p = 0.047), and also higher BMI. Myeloperoxidase levels correlated directly with insulin. In conclusion, IR PCOS young patients have higher myeloperoxidase levels.