Notes on Underactive Bladder and Chronic Urinary Retention in Older Women
Characterization of Underactive Bladder (UAB)
- Definition: Underactive bladder involves reduced detrusor contractility, leading to incomplete or ineffective bladder emptying.
- Clinical Profile: Unlike overactive bladder, these conditions are often "quiet," with symptoms that are subtle, nonspecific, or wrongly attributed to aging, mobility issues, or infections.
- Coexistence: UAB is not merely the opposite of overactive bladder; both can coexist in a single patient.
Etiology and Contributing Factors
- Detrusor Underactivity: Caused by age-related detrusor muscle changes, neurological diseases (e.g., stroke, Parkinson's disease, diabetes, spinal pathology), and medications (specifically anticholinergic drugs and centrally acting sedatives).
- Bladder Outlet Obstruction (BOO): Potential causes include pelvic organ prolapse, urethral pathology or scarring, and complications from prior pelvic or continence surgery (e.g., stress incontinence slings).
Clinical Presentation and Recognition
- Voiding Symptoms: Hesitancy, weak urinary stream, straining to void, and a sensation of incomplete emptying.
- General Symptoms: Frequent small-volume voids, recurrent urinary tract infections (UTIs), and worsening nocturia.
- Atypical Presentations: Overflow incontinence, abdominal discomfort, falls, delirium, or renal impairment in advanced cases.
- Physical Examination: Palpation to detect significant retention, pelvic examination for prolapse, and neurological assessment for underlying contributors.
- Post-Void Residual (PVR) Measurement: Assessed non-invasively via ultrasound (bladder scanners or formal imaging) or directly through in-out catheterization.
- Critical Precaution: PVR must be assessed before initiating anticholinergic therapy for urgency to avoid precipitating acute urinary retention or worsening infection risk.
Management and Therapeutic Strategies
- Primary Goals: Prioritize safety, function, and quality of life over a definitive cure.
- Behavioral Support: Physiotherapy for optimized toileting posture, pelvic floor relaxation, and behavioral techniques.
- Catheterization: Intermittent self-catheterization is preferred over permanent indwelling or suprapubic catheters due to lower long-term risks, provided the patient has sufficient dexterity and cognitive function.
- Specialist Therapies: Sacral neuromodulation may be used for some patients with nonobstructive urinary retention to restore spontaneous voiding.
Criteria for Specialist Referral
- Persistently elevated post-void residual volumes.
- Suspected or unclear bladder outlet obstruction.
- Presence of neurological disease.
- Development of recurrent infections or upper tract concerns.
- Progressive or unexplained symptoms.