Autonomic dysfunction in women with polycystic ovary syndrome

BACKGROUND: Central obesity and hyperinsulinaemia of polycystic ovary syndrome (PCOS) are associated with chronic sympathetic over activity. OBJECTIVE: To evaluate the autonomic functions and to indicate the superiority, if any, for those functions in the diagnosis of sympathetic over activity in PCOS women. MATERIALS AND METHODS: Sixty-four PCOS patients and 40 women served as the control group were studied. The two groups were subdivided according to the body mass index (BMI) into two obese and non-obese groups. Waist:hip ratio (WHR), plasma epinephrine level was estimated, sympathetic skin response (SSR); postural orthostatic tachycardia syndrome, heart rate variability (HRV), and valsalva ratio were measured in both groups. RESULTS: Compared to the control group, obese PCOS patients demonstrated higher BMI and WHR, reduced palmar SSR latency and higher amplitude, altered HRV, higher plasma epinephrine level, and rapid pulse rate. Moreover, non-obese patients show reduced palmar SSR latency and higher amplitude, higher plasma epinephrine level, and higher pulse rate. BMI and WHR of the patients were positively correlated with plasma epinephrine level; while the HRV was negatively correlated WHR. CONCLUSION: Women with PCOS exhibits altered autonomic function and sympathoexcitation is more pronounced in obese than non-obese patients; therefor the SSR could be useful auxiliary electrophysiological test to predict autonomic dysfunction in those patients. Receiver operating characteristics curve demonstrate the pulse rate in standing position as the autonomic function test that is superior to others in predicting sympathetic over activity in those patients.