Re: Lemack et al. 2007. Clinical and demographic factors associated with valsalva leak point...

Neurourology and Urodynamics 26:895 (2007)

LETTER TO THE EDITOR

Re: Lemack et al. 2007. Clinical and Demographic Factors AssociatedWith Valsalva Leak Point Pressure Among Women Undergoing Burch

Bladder Neck Suspension or Autologous Rectus Fascial SlingProcedures. Neurourol Urodynam 26:392–6

Lemack and colleagues have assessed the database ofthe SISTEr-trial to see if one of the measured parameters(i.e., VLPP) could be associated with demographic data of thepatients included in this trial. I have the following concernsabout this article:

The rationale behind the choice to compare VLPP withdemographic data is unclear. The authors state that theysought to relate demographic data to sphincteric function. Asthere are several so called sphincteric function tests (e.g., UPP,Monitorr), why did they choose VLPP?

There is no scientific proof of the validity and/or clinicalusefulness of any of these so called sphincteric function test.The only valid and useful sphincteric function test to date isthe mere symptom of stress urinary incontinence (SUI): apatient that loses urine on coughing or physical exertionmust have an incompetent sphincteric closing mechanism(assuming that there is no fistula)! Given the fact that VLPPis a non-validated test, there seems to be no rationale forcomparing the outcome of this test to any of the other data inthe SISTEr database.

For this study only female patients with SUI and hyper-mobile urethras (type II SUI) were included. The fact that theauthors applied a function test (i.e., VLPP) that is meant todiagnose intrinsic sphincteric dysfunction (type III SUI) seemsillogical.

From the literature it is known that SUI is negativelyassociated with body weight. Or in other words: overweight isa well-established risk factor of SUI. In this article the oppositewas found. Overweight appeared to be associated with higherVLPP values and in the words of the authors with better

sphincteric function. If there ever was a reason for the authorsto cast some doubt on their assumptions on the value of VLPPthis should have been the case here. To my notion the findingthat VLPP is positively correlated with BMI can only mean thatVLPP is a useless test. Of course it is laudable that attemptswere made to fit the findings into a new theory that obesepatients have better pelvic floor muscles because they con-tinuously have to lift the extra weight. As scientists, however,we should be careful to separate facts from speculation. And ifwe speculate, the drawbacks of such actions should be clearlyindicated.

In the discussion it is stated that VLPPmight be ‘‘a relativelypoor indicator of urethral sphincteric function . . . ’’ and that‘‘it’s value may be quite limited . . . ’’. Therefore, based ontheir findings the authors could have helped the urologicalcommunity a lot by declaring VLPP a useless test.

In summary, it seems that this article was based on wrongassumptions to which the authors adhered despite the factthat their own findings indicated otherwise. For sure theSISTEr database contains many other parameters that havenot yet been pulled through the authors slot machine. Ihope that this editorial comment encourages these and otherauthors to think twice before pulling the handle.

Bart L.H. Bemelmans*Professor and ChairmanDepartment of Urology

Free University Medical CenterAmsterdam, The Netherlands

No conflict of interest reported by the author(s).*Correspondence to: Bart L.H. Bemelmans, MD, PhD, Professor and Chairman,Department of Urology, Free University Medical Center, De Boelelaan 1117, NL-1081 HV, Amsterdam, The Netherlands.Published online 22 June 2007 in Wiley InterScience(www.interscience.wiley.com)DOI 10.1002/nau.20338

� 2007 Wiley-Liss, Inc.