Claire C. Yang, MD, Urologist
VA Puget Sound Health Care System, Seattle, WA
Urinary control is a very common concern among persons with multiple sclerosis, and the prevalence of bladder dysfunction is high in MS. The innervation to the bladder and urinary sphincters emanates primarily from the sacral spinal cord (with some contributions from the lumbar cord), and thus the long CNS pathways that regulate the micturition reflex are more “exposed” to the demyelinating process. The exact prevalence of urinary problems is not known because the onset is insidious, and if the symptoms are mild, they are often disregarded.
The physiological effects on demyelination on bladder control are usually one or more of the following: 1) loss of sensation of bladder fullness, 2) loss of cortical inhibition of the micturition reflex, resulting in frequency, urgency and urge incontinence, 3) loss of bladder contractility, and 4) loss of coordination between the urinary sphincters and bladder contraction. Functionally, patients experience problems containing urine, problems emptying urine, or a combination of both.
The objectives of bladder management are the same in multiple sclerosis as they are for any person with bladder dysfunction. The primary objective is to do what is necessary to preserve renal function, since problems of the bladder can result in renal deterioration. This can be achieved by emptying the bladder efficiently (completely) and regularly, whether by spontaneous voiding, clean intermittent catheterization or chronic catheterization. Fortunately, renal failure due to bladder dysfunction is not common in MS, in part because most of the patients are women, and the short (and generally, non-obstructive) female urethra allows for a “pop-off” valve in bladders with poor compliance.
The secondary objectives for bladder management are the maintenance of social continence and the avoidance of complications such as cystitis and stone formation. Additionally, a patient should not be committed to a bladder management regimen that makes her dependent on someone else for bladder emptying. For example, a tetraplegic patient should not be started on self catheterization. The mode of bladder management should be consistent with the patient’s physical and mental capacities.
After obtaining a urinary history and performing a genitourinary physical exam, one of the most important determinants of bladder management is the post void residual volume. This can be measured with an ultrasound or with bladder catheterization after voiding. How efficiently a bladder empties (i.e., how much urine is left behind after a void) will help the practitioner decide on treatment and management.
Several common scenarios exist:
a) A person with a large (>275-300 cc) post void residual on two separate occasions should perform clean intermittent catheterization, or have a chronic, indwelling catheter.
b) A patient with frequency and urgency likely has detrusor hyperreflexia, that is, bladder contractions without full cortical regulation. If the post void residual is small, then a trial of anticholinergic medications is indicated. Common side effects are dry mouth, constipation, and urinary hesitancy/retention, which are already problematic in persons with MS. Thus, careful medication titration (avoid long-acting anticholinergic medications) and aggressive bowel care (including fiber supplements, stool softeners, suppositories, mini-enemas) are necessary to avoid exacerbating one problem to treat another.
c) If a person with the same symptoms has a large post void residual (>150-200 cc), one would not prescribe anticholinergic medication unless the patient were to begin CIC.
d) A person with tolerable urinary symptoms, who is not in urinary retention or having UTIs, does not have to be treated.
Keep in mind that there is no “cookbook” method of determining which combination of behavioral modifications, medications and/or catheter use is applicable to a particular patient; each person requires an individual assessment. If an initial trial of bladder management fails to alleviate symptoms or infections, then a referral to an urologist is needed. Many persons with bladder dysfunction will require supplemental items such as medications, pads or other absorbent garments, catheters and other urine collection devices. These items are available in most VA pharmacies.
Last Updated: December 2009