The urinary tract symptoms ascribed to an enlarged prostate may be caused by bladder defects. Lifestyle changes and drugs can help.
Even though overactive bladder (OAB) is usually associated with women, it afflicts nearly one of every eight American men. OAB symptoms can also be confused with those of benign prostatic hyperplasia (BPH).
Distinguishing between obstruction and OAB can be tricky because symptoms may overlap, warns David Staskin, MD, associate professor of urology at Weill Medical College of Cornell University in New York City. As a result, there is sometimes a lack of understanding about whether a patient’s symptoms are the result of a primary bladder problem—with or without an identifiable cause—or are secondary to obstruction. “If men are not obstructed,” he adds, “you can probably treat them the same way you’d treat women with OAB because the pathophysiology is the same.”
Ryan Paterson, MD, assistant professor of urology at the University of British Columbia in Vancouver, points out that OAB produces specific irritative symptoms, including urinary frequency, urgency, and nocturia, in the absence of significant pathology, such as bladder tumors or bladder stones. “If a patient has a stroke and develops an unstable bladder, it’s not OAB,” he says. Less frequent causes of lower urinary tract symptoms (LUTS) include infection, urethral stricture, advanced prostate cancer, and bladder stones.
Genders not so different?
Simon Hall, MD, chairman of the Department of Urology and director of the Barbara and Maurice A. Deane Prostate Health and Research Center at Mount Sinai School of Medicine in New York City, says it’s not clear how OAB differs in men and women. “Symptoms that we ascribe to prostate problems in men may in fact be due to changes that occur in women as well,” he explains. “For example, as we age, the bladder becomes stiffer and less elastic. In women there are postmenopausal changes, too, but there is some commonality between the genders that we have not fully appreciated.”
When a man presents with LUTS, Dr. Hall first tries to gauge how bothersome the problem is. “I ask whether he’s had to make alterations in his lifestyle. Does he make it a point not to drink anything when he goes out? Does he carry a container in the car?” Dr. Hall also rules out medical problems, such as bladder stones, bleeding, infection, urinary retention, and kidney problems. If none is present, he says, it’s a lifestyle issue. “I then may tell patients that as long as their prostate-specific antigen (PSA) levels are within normal range, it’s unlikely that they’ll get significantly worse. In such cases, some men will choose to defer treatment.”
Dr. Paterson says all patients should receive an American Urological Association symptom score, which includes a quality-of-life index. The index can be found online at www.prostate-cancer.org/tools/forms/aua_symptom_form.pdf (accessed July 12, 2007).
Some patients may have a relatively high symptom score but not be that bothered, while others can have low scores but be very distressed, Dr. Paterson says.
“To some extent this has to do with a man’s stage of life. A busy executive who has to urinate three times each night may be more bothered than a retiree. If a patient has BPH, the clinician could ask, ‘Can you live with the symptoms the way they are now?’ If the answer is ‘yes,’ active surveillance may be an appropriate strategy,” notes Dr. Paterson.
Changing management strategiesPatients who want OAB symptom relief can be placed on an anticholinergic. “There are now five different medications, along with a patch,” Dr. Hall says. “Patients who are already taking a lot of medication may prefer a patch. If patients are taking anticholinergics, though, you have to monitor them to be sure they are not in retention.”
In the past, continues Dr. Hall, “it was considered a major faux pas to put the average man with urinary problems on meds to treat OAB. But some studies show you can use OAB meds to treat men with mild-to-moderate LUTS and that treating patients with phosphodiesterase-5 inhibitors will improve urinary function.”Following evaluation, most patients with obstructive symptoms are put on alpha blockers, which is the standard of care, Dr. Hall says. “If a patient has an elevated PSA in addition to symptoms but no evidence of cancer, it’s reasonable to take this route. I put average patients with relatively small prostate glands (25-30 g) on finasteride (Proscar) or dutasteride (Avodart),” he says. “If a patient has a prostate volume >50 cc, putting him on finasteride will reduce his likelihood of developing urinary retention.” Prostate size is determined by ultrasound.
“Nowadays some urologists are putting these patients on anticholinergics. But before we do that on a large scale, I think we need more studies. Lots of primary-care clinicians treat men with LUTS and are not ready to put patients on anticholinergics because we don’t yet know if they’re just as safe and effective long term as they are short term.”
Dr. Paterson recommends referral for a cystoscopy when a patient’s symptoms are primarily irritative and there is no evidence of obstruction, neurologic disease, or infection. If the results produce no evidence of malignancy, the next step is to take a dietary history. “Dietary change is something we need to stress more—avoiding or limiting caffeinated beverages, acidic and spicy foods, and alcohol,” he counsels. “We also need to tell men to do Kegel exercises and discuss fluid restriction.”
Only after these options have been tried does Dr. Paterson bring up pharmacologic therapy. “If a patient has obstructive, irritative, or mixed voiding symptoms and no absolute need for surgery, you can start off with an alpha blocker and see how he does.”
Drug costs a factor
Some patients, Dr. Paterson adds, will still have pronounced symptoms. For them, combination treatment with alpha blockers and anticholinergics may be appropriate. “I also think it is important to talk to patients about what their drug plans will cover. There is no point in putting patients on a drug that’s going to cost $50 a month if they can’t afford it. Clinicians and patients also should discuss the fact that symptoms can fluctuate.”
Dr. Staskin points out that women with OAB and men with OAB who are not obstructed will have the same symptoms, and both will respond to anticholinergic therapy. “In the past, anticholinergic drugs were thought to be unsafe in men.
The presumption was that men would go into urinary retention because the prostate was blocking the urethra,” Dr. Staskin says. “Urologists have changed their minds. We don’t think the drugs affect contractility as much as we used to. The data show that if you have treated obstruction with alpha blockers or 5α-reductase inhibitors, you can add an anticholinergic. Studies that have been done so far suggest that men with smaller prostates do better on combination therapy.”
Severe OAB that resists all available conventional treatments presents a therapeutic dilemma, but promising new therapies are currently under investigation. Michael Chancellor, MD, director of neurourology and female urology programs at the University of Pittsburgh Medical Center, has reported good results after injecting botulinum toxin into the base of the bladder. Use of the toxin for OAB is not FDA-approved, however.
Dr. Staskin points out recent studies which suggest that phosphodiesterase-5 inhibitors may improve LUTS in men. “Could improved blood flow to the bladder be responsible for improvement in voiding symptoms? Maybe these drugs cause smooth-muscle relaxation in the bladder neck and prostate. Right now this is just a hypothesis, but I think it’s worth looking at. Beta3-agonists are also a promising drug class in development through a direct effect on the bladder without anticholinergic side effects.”