Endothelial function and peak heart rate in normal-weight women with polycystic ovary syndrome and normal-weight controls.

CONTEXT: Assess endothelial dysfunction in normal weight women with polycystic ovary syndrome (PCOS) after exercise.

OBJECTIVE

To compare brachial artery Flow Mediated Dilatation (FMD) between normal-weight with PCOS and normal-weight control women. The secondary endpoint is to explore if FMD shows correlation with blood pressure, heart rate, maximal oxygen consumption (VO2 max), and VO2 75%. DESIGN AND PATIENTS: Thirty normal-weight PCOS and thirty BMI- and age- matched control women were studied via brachial artery FMD before and after treadmill exercise.

SETTING

Obstetrics and Gynecology. INTERVENTIONS: Subjects before and after treadmill exercise had measurements of brachial artery FMD, heart rate, VO2 max, peak heart rate. Oral glucose tolerance test was performed. MAIN OUTCOME MEASURE: Flow Mediated Dilatation change after a single bout treadmill exercise.

RESULTS

Mean FMD values decreased significantly at 30 min following exercise compared to baseline in controls, while they did not change in PCOS women. FMD was lower both at baseline and after exercise in PCOS group. Backwards multiple linear regression analysis revealed peak heart rate as the best negative predictor of baseline FMD in PCOS, while it was a positive predictor in controls. In controls peak heart rate measurements were the best positive predictor of Delta Area Under the Curve FMD during exercise.

CONCLUSIONS

These data could show a defective endothelial system in normal-weight women with PCOS. As heart rate and endothelial function are both components of sympathetic nervous system activity, the negative correlation between them, compared to controls, could imply a possible sympathetic system dysfunction in PCOS.