Urodynamic Changes 12 Months After Retropubic and Transobturator Midurethral Slings Stephen Kraus, Gary Lemack, Toby Chai, Wendy Leng, Michael Albo, Elizabeth Mueller, Larry Sirls, Tracey Wilson, Peggy Norton, Liyuan Huang and Heather Litman for the UITN AIM AND OBJECTIVES To evaluate preoperative and 12-month post-operative Urodynamics (UDS) in a multi-institutional setting with extensive subjective and objective patient outcome measures. To determine if changes in UDS parameters: 1) Differ between retropubic (RMUS) and transobturator (TMUS) midurethral sling procedures 2) Are associated with successful treatment outcome. If an association exists, then to further elucidate the MOA of the MUS. MATERIALS AND METHODS Trial of Midurethral Slings (TOMUS) was a multicenter, randomized equivalence trial comparing outcomes with RMUS and TMUS conducted at 9 clinical sites through the Urinary Incontinence Treatment Network (UITN) with IRB approval at all sites. 597 women with predominant stress urinary incontinence (SUI) randomized to RMUS or TMUS and underwent standardized UDS before and 12 months after surgery. Retreatment for SUI prompted 12 month assessment battery prior to initiation of retreatment. Inclusion criteria included self-reported SUI, pure or predominant SUI on the MESA questionnaire, positive CST. Postoperative evaluations were performed at 2 and 6 weeks, and 6, 12 and 24 months with primary outcomes determined at 12 months. Objective Success • negative stress test at 300cc bladder volume • negative 24 hour pad test • no retreatment Subjective Success •self-reported absence of symptoms •no leakage recorded on voiding diary •no retreatment Standardized UDS and interpretation guidelines based on ICS Good Urodynamics Practice Guidelines. Surgeon remained blinded to UDS results unless needed for treatment of postoperative symptoms. Data reported for women with analyzable UDS at both time points and known outcome status. Linear models fit to predict change in UDS measures from pre to post surgery. Chi-square tests used to assess differences by treatment group for DO. RESULTS TMUS RMUS Inter- action p-value N Pre Post Difference Post – Pre P N Pre Post Difference Post – Pre P NIF Qmax 226 25 (12) 20 (9) -5 (14) <0.001 212 25 (12) 20 (9) -5 (12) <0.001 0.88 NIF Qave 225 12 (6) 10 ( 5) -2 (6) <0.001 211 12 (6) 10 (5) -2 (6) <0.001 0.93 Time Qmax 226 14 (17) 13 (15) -1 (18) 0.65 211 13 (15) 14 (21) 1 (23) 0.52 0.42 Void Vol 226 313 (138) 307 (108) -6 (161) 0.56 214 311 (134) 313 (105) 2 (151) 0.82 0.57 PVR** 197 21 (31) 25 (40) 3 (50) 0.34 186 23 (34) 33 (47) 10 (52) 0.009 0.21 Table 1. Comparison Changes in NIF with Mean and SD after SUI Surgery by Treatments Additional Results: No changes in compliance seen No difference in rate of de novo detrusor overactivity (p=0.61) •TMUS: 10/233 (4.3%) •RMUS: 12/216 (5.5%) No difference in resolution rate of detrusor overactivity (p=0.94) •TMUS: 16/26 (61.5%) •RMUS: 20/33 (60.6%) No UDS changes associated with subjective or objective outcome Table 2: Comparison of Changes in CMG and UPP with Mean and SD after SUI Surgery by Treatments TMUS RMUS Inter- action p-value N Pre Post Difference Post – Pre P N Pre Post Difference Post – Pre P First sensation 247 119 (84) 141 (85) 22 (102) <.001 247 115 (82) 142 (98) 27 (107) <0.001 0.58 First urge 248 233 (120) 248 (106) 15 (115) 0.04 247 225 (122) 260 (116) 35 (132) <0.001 0.07 MCC 250 358 (121) 348 (110) -10 (113) 0.16 249 349 (125) 357 (112) 9 (114) 0.24 0.07 MUCP 204 68 (31) 63 (31) -6 (34) 0.02 211 67 (34) 60 (29) -6 (32) 0.005 0.82 FUL 204 32 (8) 31 (7) -1 (10) 0.33 211 31 (8) 31 (8) 0 (10) 0.85 0.41 TMUS RMUS Inter- action p-value n Pre Post Difference Post – Pre P n Pre Post Differenc e Post – Pre P Qmax 222 22 (11) 20 (9) -2 (11) 0.005 226 22 (11) 19 (9) -3 (11) <0.001 0.28 Voided volume 224 385 (143) 380 (134) -5 (145) 0.62 226 383 (144) 370 (127) -13 (156) 0.21 0.56 Pdet@ Qmax 137 18 (12) 21 (13) 3 (13) 0.01 124 18 (11) 23 (12) 5 (11) <0.001 0.19 BOOI 137 -24 (25) -19 (23) 5 (26) 0.02 124 -23 (23) -16 (25) 7 (25) 0.003 0.68 Time Qmax 218 20 (26) 19 (26) -1 (35) 0.62 222 25 (56) 19 (17) -6 (57) 0.10 0.25 Delta Pabd 137 7 (20) 1 (15) -6 (23) 0.003 124 4 (16) 2 (13) -2 (19) 0.19 0.18 Table 3: Comparison of Changes in PFS with Mean and SD after SUI Surgery by Treatments *The interaction test statistic will test the hypothesis that the difference between pre and post data is the same in the TMUS and RMUS treatment arms. CONCLUSIONS • UDS changes similar in RMUS and TMUS • No significant change in MUCP after MUS despite proven efficacy • Is MUS efficacy not reliant on MUCP changes, or is MUCP incapable of detecting changes induced by MUS? • Flow rates lower at 12 months in both TMUS & RMUS • Increased Pdet@Qmax in both RMUS and TMUS by 3-5 cm H 2 O • No UDS changes associated with subjective or objective outcomes. • These findings suggest MUS not as “obstructive” as PVS. UDS changes are not related to treatment outcomes after MUS as they were after Burch and PVS. Continence Treatment Centers: Beaumont Hospital, MI; Oakwood Hospital, MI; Loyola University Medical Center, Chicago; University of Alabama-Birmingham; University of California San Diego; University of Maryland, Baltimore; University of Pittsburgh; University of Texas Southwestern, Dallas; University of Texas Health Sciences Center, San Antonio; University of Utah. Biostatistical Coordinating Center: New England Research Institutes, Watertown, MA The UITN is supported by cooperative agreements from the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) in collaboration with the National Institute of Child Health and Human Development (NICHD)