Analysis of heart rate variability in female patients with overactive bladder.

OBJECTIVES: To characterize autonomic dysfunctions in patients with an overactive bladder (OAB), we compared their heart rate variability (HRV) with the HRV of a normal population.
METHODS: Electrocardiographic signals were obtained from 40 female patients (mean age 46.4 +/- 12.1 years) and 131 healthy female controls (mean age 45.6 +/- 7.24 years) in a resting state.
RESULTS: The time domain analysis of the electrocardiographic signals for patients with OAB, including the standard deviation of the N-N interval and the square root of the mean squared differences of successive N-N intervals, revealed significantly lower values than those of the controls (P <0.05). Evidence was found of decreased total power, very low frequency, and high frequency signals in patients with OAB (P <0.05), but no significant differences were found in other parameters such as low frequency or the low frequency/high frequency ratio.
CONCLUSIONS: Patients with OAB exhibited different HRV parameters compared with normal controls. With the exception of low frequency and the low frequency/high frequency ratio, all HRV parameters in patients with OAB were lower than those in normal controls. These decreased values indicate that they may have some kind of disease or imbalance in the autonomic nervous system. Thus, a study of HRV may serve as a tool to evaluate altered autonomic nervous system activity in such patients.