Autonomic nervous system changes in men with chronic pelvic pain syndrome.

Purpose: We investigated the role of the autonomic nervous system in the chronic pelvic pain syndrome by studying blood pressure changes, power spectral analysis of heart rate variability, and hand and foot sympathetic skin responses in men with the chronic pelvic pain syndrome and healthy controls.

Materials And Methods: We recruited 22 men with the chronic pelvic pain syndrome and 20 controls. The subjects underwent 5-minute resting and standing blood pressure readings as well as electrocardiogram recordings. Heart rate variability was evaluated using the low frequency (sympathetic) and high frequency (parasympathetic) components of power spectral analysis. We recorded sympathetic skin responses with surface electrodes placed on the dorsal and ventral sides of both hands and feet, measuring amplitude and latency.

Results: Mean blood pressure readings for supine and standing were higher in the chronic pelvic pain syndrome group. Between group comparisons revealed no differences in low or high power spectra for supine or standing positions. When subjects were taken to standing from the supine position, mean low frequency power increased in the controls and decreased in the chronic pelvic pain syndrome group. High frequency power, a reflection of parasympathetic activity, decreased significantly in the control group while the decrease was not statistically significant in the chronic pelvic pain syndrome group. There was no difference between the 2 groups for hand and foot sympathetic skin response latency and amplitudes.

Conclusions: The heart rate variability and blood pressure changes suggest altered autonomic nervous system responses in men with the chronic pelvic pain syndrome. Sympathetic skin response findings were not conclusive. Heart rate variability and blood pressure findings provide a basis for therapeutic manipulation of the autonomic nervous system for management of the chronic pelvic pain syndrome.