Cardiac Autonomic Nervous System Activity in Children with Bladder and Bowel Dysfunction.

PURPOSE:Bladder and bowel dysfunction is a common reason for referral to pediatric urology. The role of the autonomic nervous system in the pathogenesis of bladder and bowel dysfunction has not been well investigated. We compared autonomic nervous system activity in children with bladder and bowel dysfunction to that in healthy controls. We hypothesized that children with dysfunction have a different autonomic profile as measured by parameters from spectral analysis of heart rate variability and impedance cardiography. MATERIALS AND METHODS:We recruited 40 children, including 25 girls, with a median age of 10 years (range 5 to 18) in whom bladder and bowel dysfunction was clinically diagnosed by a validated questionnaire and 19 healthy controls, including 9 girls, with a median age of 8 years (range 5 to 16). Cardiac autonomic activity was assessed at baseline and during voiding. The primary outcome measures were the main parameters of heart rate variability, including total power and high frequency, as well as pre-ejection period and heart rate. RESULTS:Comparison of outcomes at baseline showed significantly lower total power and high frequency heart rate variability in bladder and bowel dysfunction cases (p = 0.001 and 0.002, respectively). Children with dysfunction also showed a significantly smaller decrease in sympathetic nervous system activity during voiding (p = 0.05). CONCLUSIONS:Our results demonstrate that compared to healthy controls children with bladder and bowel dysfunction show a different cardiac autonomic profile at rest and in response to voiding. This difference may be used in future studies to further clarify the pathophysiology of bladder and bowel dysfunction, and introduce novel treatment targets to manage the condition.