NEW YORK (Reuters Health) – Uncomfortable and expensive urodynamic tests may be unnecessary before surgery for stress urinary incontinence, according to a new study involving 630 women at 11 medical centers.
Researchers found no difference in the success rate of urinary incontinence surgery for women who underwent the tests and women who were simply screened in an office exam.
Doctors “need to do a careful history and exam, and if you do that you probably don’t need an expensive, uncomfortable and invasive test,” lead researcher Dr. Charles Nager of the University of California, San Diego, told Reuters Health.
About 260,000 women have surgery each year for stress urinary incontinence, a problem that affects up to half of U.S. women at some point in their lives.
A combination of tests is sometimes ordered before surgery at a cost of $500 or more. One measures urine flow while voiding. Another involves filling the bladder and measuring both the pressure inside the bladder and the abdominal pressure on the bladder with the help of a separate tube in the rectum.
The goal is to identify the best surgical technique for correcting the problem. Although good estimates are hard to find, “it seems like these tests are done most of the time,” said Dr. Nager. “In some countries testing is almost universally done.”
To see if the test results affected the success rate for surgery, participants first had an office evaluation. To be enrolled in the trial, according to a report published online today in The New England Journal of Medicine, women had to be at least 21 years of age or older, with a history of symptoms of stress urinary incontinence for at least 3 months, a score on the Medical, Epidemiological, and Social Aspects of Aging (MESA) questionnaire for stress urinary incontinence that was greater than the score on this questionnaire for urgency incontinence, a postvoiding residual urine volume of less than 150 ml, a negative urinalysis or urine culture, a clinical assessment of urethral mobility, a desire for surgery for stress urinary incontinence, and a positive provocative stress test (defined as an observed transurethral loss of urine that was simultaneous with a cough or Valsalva maneuver at any bladder volume).
Half the women were randomly assigned to undergo additional tests: noninstrumented uroflowmetry with a comfortably full bladder, filling cystometry with Valsalva leak-point pressures, and a pressure-flow study. Urethral pressure profilometry or urodynamic testing with the use of video was permitted if it was part of the hospital’s routine preoperative protocol.
Women who demonstrate stress incontinence in the office but can empty their bladder and haven’t had surgery before account for most patients with stress urinary incontinence, Dr. Nager said.
Based on a variety of questionnaires, the researchers found that after 12 months, surgery was successful in about 77% of women whether they did or didn’t get additional testing.
They also found the extra testing made no difference when it came to quality of life, patient satisfaction, voiding problems or other measures.
And although findings from the extra tests often led doctors to change their specific incontinence-related diagnosis, that didn’t affect how they managed patients surgically.
“We therefore question the clinical importance of such diagnostic changes,” the researchers concluded.
Dr. J. Quentin Clemens of the University of Michigan Medical Center in Ann Arbor, a urologist who wasn’t connected to the research, said that although this type of study hadn’t been done before, the findings are consistent with what urologists would anticipate and with guidelines from the American Urological Association.
“I think it’s what people would have expected given the type of patients they were studying,” said Dr. Clemens.
He noted that the research involved women where the diagnosis was clear and the symptoms of stress incontinence were unambiguous.
“There are many patients where, after doing the basic workup, the diagnosis isn’t certain,” he said. And in those cases the follow-up testing can be “extremely important to make sure we’re doing the right thing,” Dr. Clemens told Reuters Health.
“Unfortunately, many physicians don’t even look for leakage,” Dr. Nager said. Some, he added, probably find it “easier and more lucrative” to just do the more advanced and expensive testing.
Automatically ordering that extra testing on all incontinence patients wouldn’t be consistent with guidelines, according to Dr. Clemens. The new research “helps to reinforce the message, so I think (the study) will have some effect,” he added.
The National Institute for Health and Clinical Excellence in the UK has also recommended against such pre-surgery tests for women who clearly have stress incontinence.
N Engl J Med 2012.