Assessment of cardiac autonomic modulation in the bladder filling process of women with urinary incontinence: the perspective of physiotherapy

ABSTRACT The behavior of the Autonomic Nervous System, through Heart Rate Variability (HRV), during the bladder filling phases of women with and without urinary incontinence (UI) was compared. The International Consultation on Incontinence Questionnaire - Short Form was applied for UI self-diagnosis. For the HRV analysis, electrocardiogram (ECG) records were used, 6 of them were recorded during bladder filling. To quantify HRV, the following methods were used: time domain (milliseconds); frequency (Hertz) and non-linear measurements. Logarithmic transformation (Log) was applied to these parameters. In the comparison of normal data means, the t-test was applied and the Mann-Whitney test was applied for the non-normal data. The participants consisted of 64 women (64.8±6.73 years), 33 with UI and 31 without. The logarithm of the LF and HF ratio (LogLH/HF) was significantly higher (p<0.05) in the continent group at all phases of the bladder filling. Bladder volumetric capacity was significantly higher in the continent women (p=0.0015). Frequency analysis demonstrated a reduction in sympathetic function and an increase in parasympathetic function in incontinent women. The continent women presented better autonomic balance, during the whole process of bladder filling compared to incontinent ones. The reduction of sympathetic function as well as the increase of the parasympathetic function in the incontinent women could be reported for a decrease of the detrusor relaxation capacity and an increase of the contractions, still in the bladder filling phase, both associated with UI.