Preoperative Urodynamic Parameters (Valsalva Leak Point Pressure and Maximum Urethral Closure Pressure), Urinary Collagen and Plasma Vitamin D Levels as Predictors of Mid Urethral Sling Surgery Outcome.
OBJECTIVE
To determine the best predictor of the mid urethral sling outcome we calculated the AUC of ROC curves of preoperative parameters, including Valsalva leak point pressure, maximum urethral closure pressure, urinary NTx (N-telopeptide of crosslinked type I collagen) and plasma vitamin D values (D2, D3 and D2 plus D3).


METHODS
This was an ancillary study of TOMUS (Trial of Mid-urethral Slings) and the ValUE (Value of Urodynamics Evaluation) trial in which subjects underwent mid urethral sling surgery for stress urinary incontinence. Valsalva leak point pressure and maximum urethral closure pressure were measured in 427 subjects, whereas NTx, vitamin D2, vitamin D3 and vitamin D2 plus D3 levels were obtained from 150, 116, 115 and 116 subjects respectively. Outcome success was defined using identical outcome (subjective and objective) variables for all subjects. ROC curves with corresponding AUC values were compared.


RESULTS
TOMUS and ValUE subjects were significantly different in age, body mass index, UDI (Urogenital Distress Inventory) scores. TOMUS subjects had a lower surgical success rate compared to ValUE subjects (66.3% vs 76.0%, p = 0.03). The AUC values of Valsalva leak point pressure, maximum urethral closure pressure, NTx, and vitamins D2, D3 and D2 plus D3 were 0.542, 0.561, 0.702, 0.627, 0.645 and 0.640, respectively. The AUC of NTx was significantly higher than the AUCs of Valsalva leak point pressure and maximum urethral closure pressure (p = 0.02 and 0.03, respectively).


CONCLUSIONS
Urinary NTx was the best predictor of the mid urethral sling outcome. This test is not only noninvasive, it is also modifiable. Finding ideal modifiable risk factors prior to mid urethral sling surgery should be subject to future investigations.
Departments of Urology and Obstetrics, Gynecology and Reproductive Sciences, Yale University School of Medicine, New Haven, Connecticut. Electronic address: toby.chai@yale.edu.
Toby C
TC
Chai
Department of Obstetrics, Gynecology and Reproductive Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania.
Pamela A
PA
Moalli
Department of Obstetrics and Gynecology, University of Alabama at Birmingham, Birmingham, Alabama.
Holly E
HE
Richter
Departments of Urology and Obstetrics, Gynecology and Reproductive Sciences, Yale University School of Medicine, New Haven, Connecticut.
AeuMuro G
AG
Lake
New England Research Institutes, Watertown, Massachusetts.
Hae-Young
HY
Kim
Department of Reproductive Medicine, University of California-San Diego, San Diego, California.
Charles W
CW
Nager
Department of Urology, Beaumont Hospital, Royal Oak, Michigan.
Larry T
LT
Sirls
Department of Urology, Loyola University, Chicago, Illinois.
Linda
L
Brubaker
National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, Maryland.
John W
JW
Kusek
D015415:Biomarkers / Q000097:blood / Q000652:urine; D015992:Body Mass Index; D003094:Collagen / Q000652:urine*; D005260:Female; D006801:Humans; D008875:Middle Aged; D011312:Pressure; D011379:Prognosis; D012307:Risk Factors; D053825:Suburethral Slings; D014521:Urethra / Q000503:physiopathology / Q000601:surgery*; D014550:Urinary Incontinence, Stress / Q000378:metabolism / Q000503:physiopathology / Q000601:surgery*; D014563:Urodynamics / Q000502:physiology*; D013520:Urologic Surgical Procedures / Q000379:methods*; D014636:Valsalva Maneuver; D014807:Vitamin D / Q000097:blood*
D015415:Biomarkers; D014807:Vitamin D; D003094:Collagen
biomarkers; outcome assessment (health care); suburethral sling; urethra; urodynamics