Urinary Frequency and Urgency: How to Identify the Cause and Treat

My 60-year-old male patient complains of urgency and frequency of urination.A urologist found no evidence of benign prostatic hypertrophy. Results of urinalysisand a chemistry panel were normal. Extended-release tolterodine was prescribed,but the patient did not wish to take it. What other diagnostic and therapeuticmeasures do you suggest?
-- Gadi Gichon, MD
   Delray Beach, Fla
Frequent urination has a number of causes. If repeated urinalyses are negative,it is unlikely that infection or bladder cancer is responsible. Patientsmay have urinary frequency as a result of excessive fluid intake, inabilityto concentrate urine, incomplete emptying of the bladder, or stress. Urinaryurgency--in which the urge to urinate develops suddenly and, ifignored, may lead to incontinence--is usually a sign of an involuntary detrusorcontraction ("overactive bladder").
I recommend referral to a urologist for a pressure-flow study. Before thestudy, the patient is asked to keep a 48-hour diary in which he records thetime and amount of all fluid intake and the time and amount of each voiding.He brings this diary with him when he comes in for the test.
The pressure-flow study starts with the recording of bladder pressurewhile the bladder is filling; if involuntary detrusor contractions are present duringthe filling phase, they are recorded. The recording of bladder pressurewhile filling also provides information about bladder tone, sensation, and capacity.When the bladder is full, the patient is asked to void, and the voiding flowrate and pressure are recorded. The amount of urine that remains in the bladderafter voiding is also noted.
A low voiding flow rate together with high voiding pressure is evidence ofobstruction. If both the voiding flow rate and the voiding pressure are low, thebladder may be atonic.
If the patient has incomplete bladder emptying associated with obstruction,I would recommend surgery to relieve the obstruction. If he has incompleteemptying associated with bladder atony, the current method of treatment isclean, intermittent self-catheterization.
If the patient is able to empty the bladder well and has detrusor instability,an anticholinergic medication, such as extended-release tolterodine, is indicated.Such agents always produce side effects, such as dry mouth, to somedegree.
Frequent urination that results from excessive fluid intake can be controlledby educating the patient. Finally, frequent urination that results from stress ("irritablebladder syndrome") is best treated by helping the patient to better managethe stresses in his life.
-- Drogo K. Montague, MD
   Urological Institute
   The Cleveland Clinic Foundation
   Cleveland