Autonomous nervous system activity in women with detrusor overactivity

To identify autonomic dysfunction among patients with urinary incontinence (UI) with or without detrusor overactivity (DO), we measured and compared heart rate variability (HRV) in these groups.

We studied HRV in 12 female UI patients with DO (mean age, 57.3+/-11.0 years) and 53 female UI patients without DO (mean age, 56.8+/-9.8 years). HRV parameters were measured by SA-3000P(R). Heart rates, the time domain index, and the frequency domain index were compared. To compare time domain indexes, we used the standard deviation of the N-N interval (SDNN), the square root of the mean squared differences of successive N-N intervals (RMSSD), and the frequency domain indexes total power (TP), very low frequency (VLF), low frequency (LF), high frequency (HF), and the low-frequency/high-frequency ratio (LF/HF ratio).

RMSSD values were lower in UI patients with DO than in those without DO, but the values of SDNN and HR showed no significant difference. Whereas the values of LF and HF were lower in UI patients with DO than in those without DO, the LF/HF ratio was higher. TP and VLF were not significantly different.

RMSSD, HF, and LF were lower in DO patients than in controls without DO, but the LF/HF ratio was higher. This suggests that both sympathetic and parasympathetic activity is attenuated in DO, but the autonomic imbalance is higher.