Pathogenesis of reduced or increased bladder sensation.

OBJECTIVE: Pathogenesis of reduced or increased bladder sensation is not well known. Hence, we systematically investigated the frequency of reduced or increased bladder sensation in neurologic/mental diseases.
METHODS: We analyzed 911 patients who were referred from within our hospital. Data registries included a diagnosis, a lower urinary tract symptom questionnaire, a urodynamic study, and neurological examinations. Reduced bladder sensation is defined as bladder volume at the first sensation >300 ml. Increased bladder sensation is defined as bladder volume at the first sensation <100 ml. These patients were stratified into those with and without DO.
RESULTS: Neuropathies are the most common cause of reduced bladder sensation (33.3-43.8% in diabetic neuropathy, etc.). Myelopathies are the second most common cause (17.4-25.0% in multiple sclerosis, etc.). Less common is brain diseases (9.6% in multiple system atrophy, etc.). In contrast, myelopathies are the most common cause of increased bladder sensation without DO (25.0-40.0% in spinal forms of systemic lupus erythematosus, Sjogren's syndrome, etc.). Neuropathies are the second most common (17.3-22.2% in post-pelvic organ surgery, diabetic neuropathy, etc.). Less common is brain/mental diseases (20.0% in psychogenic bladder dysfunction, 8.1% in Parkinson's disease, etc.).
CONCLUSION: The present study revealed that neuropathies are the most common cause of reduced bladder sensation in neurologic/mental diseases. Increased bladder sensation without DO occurs mainly in peripheral and central sensory pathway lesions, as well as in basal ganglia lesions and psychogenic bladder dysfunction. Reduced and increased bladder sensation should be a major treatment target for maximizing patients' quality of life.