OBJECTIVE: To identify factors that may contribute to patient satisfaction with outcome in women who received retropubic and transobturator midurethral slings.
METHODS: Satisfaction was assessed 12 months postsurgery as a planned analysis in 597 participants from a multicenter randomized trial comparing retropubic with transobturator midurethral slings using the Incontinence Surgery Satisfaction Questionnaire. Significantly related variables associated with satisfaction in univariable analyses were entered into multivariable logistic regression models to test their independent association with satisfaction.
RESULTS: One year after surgery, 264 (88.6%) in the retropubic group and 263 (88.0%) in the transobturator group completed satisfaction questionnaires. Both treatment groups demonstrated a high level of satisfaction with respect to urine leakage (retropubic 85.9% compared with transobturator 90.0%; P=.52), urgency to urinate, frequency of urination, capability of physical activity, social activity, ability to engage in sexual activity, and from an emotional standpoint. Baseline characteristics associated with reduced satisfaction were higher Medical, Epidemiologic, and Social Aspects of Aging Questionnaire urgency subscale scores, detrusor overactivity, and diabetes mellitus. The severity of both objective (frequency of incontinence episodes, pad test weight) and subjective (Incontinence Impact Questionnaire and Urogenital Distress Inventory score) measures of incontinence at baseline and the patients' perceptions of preoperative severity of incontinence and expectations of achieving postoperative cure or improvement were not statistically different between satisfied and unsatisfied patients. In the final multivariable model, satisfaction was associated with overall treatment success (odds ratio [OR] 2.57, 95% confidence interval [CI] 1.29-5.13], greater reduction in Urogenital Distress Inventory (OR 0.97, 95% CI 0.96-0.98) and Incontinence Impact Questionnaire scores (OR 0.99, 95% CI 0.98-0.99), and fewer complications (OR 0.55, 95% CI 0.30-0.99).
CONCLUSION: The high level of satisfaction seen after midurethral sling procedures is associated with greater objective and patient-perceived improvement of stress incontinence and fewer complications.
CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, www.clinicaltrials.gov, NCT00325039.
LEVEL OF EVIDENCE: II
Patient satisfaction with either type of midurethral sling surgery is high at 12 months, with better symptom improvement and fewer surgical complications predicting higher satisfaction scores.
University of Texas Southwestern, Dallas, Texas; the New England Research Institutes, Watertown, Massachusetts; the University of Pittsburgh, Pittsburgh, Pennsylvania; Department of Veterans Affairs and The University of Alabama at Birmingham, Birmingham, Alabama; Loyola University Stritch School of Medicine, Chicago, Illinois; the University of Maryland, Baltimore, Maryland; and the University of California, San Diego, California.
Corresponding author: Clifford Y. Wai, MD, Division of Female Pelvic Medicine and Reconstructive Surgery, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390-9032; e-mail: firstname.lastname@example.org.
* For a list of other members of the Urinary Incontinence Treatment Network, see the online Appendix available at http://links.lww.com/AOG/A373.
Supported by cooperative agreements (U01 DK58225, U01 DK58229, U01 DK58234, U01 DK58231, U01 DK60379, U01 DK60380, U01 DK60393, U01 DK60395, U01 DK60397, and U01 DK60401) from the National Institute of Diabetes and Digestive and Kidney Diseases and by the Eunice Kennedy Shriver National Institute of Child Health and Human Development of the National Institutes of Health.
Financial Disclosure Dr. Zyczynski is a consultant for Johnson & Johnson. Dr. Stoddard owns stock in Bristol Myers Squibb, Johnson & Johnson, and Proctor & Gamble. The other authors did not report any potential conflicts of interest.
Presented at the 38th Annual Scientific Meeting of the Society of Gynecologic Surgeons, Baltimore, Maryland, 13–15 April 2012.
Patient satisfaction after stress incontinence surgery can be influenced by many factors, including inherent patient-specific expectations, postoperative continence status, and complications. Mallett et al1 reported that patients with inappropriate treatment expectations who undergo stress incontinence surgery are at increased risk for dissatisfaction after surgery. Participants in a large randomized surgical trial comparing the Burch colposuspension to the fascial sling (SISTEr trial) experienced greater satisfaction related to better incontinence symptom control and reduced symptom distress in both treatment groups.2 These investigators also reported that participants who had more preoperative urge incontinence symptoms were less likely to experience satisfaction postoperatively. In nonsurgical patient populations, satisfaction is also related to patient perception of improvement and reduced bother from incontinence-related symptoms.3
Midurethral slings are widely considered first-line surgery for treatment of female stress incontinence because of similar efficacy yet reduced morbidity, as compared with historical operations, including fascial slings and colposuspensions. Recently, the Urinary Incontinence Treatment Network reported equivalence for objective outcomes in 597 women who participated in a large randomized surgical trial comparing retropubic and transobturator midurethral slings, the Trial of Midurethral Slings (TOMUS).4 Although treatment success traditionally has been defined by cure rate and symptom improvement, patient-reported outcomes, particularly satisfaction, have become increasingly recognized as complementary measures of success. Thus, the objective of this planned analysis was to identify factors that may contribute to patient satisfaction with outcome. Factors considered were demographic variables and several clinical variables, including preoperative symptom severity, adverse events, and treatment outcomes.
MATERIALS AND METHODS
This planned analysis was conducted with data from participants in the TOMUS, a multicenter randomized equivalence trial that compared outcomes of the retropubic or transobturator midurethral sling in women with symptoms of stress predominant urinary incontinence (UI) for 3 or more months and a positive standardized stress test result.4 Concomitant vaginal procedures were permitted, with the exception of any synthetic graft or anterior compartment biologic graft. All sites obtained local Institutional Review Board approval, and participants provided written informed consent.
Details of the TOMUS trial design, methods, and primary results have been reported.4,5 Briefly, eligible women were randomly assigned to surgical procedure in the operating room after anesthetic induction using a permuted block randomization schedule with stratification by clinical site. The specific midurethral sling procedures performed consisted of the original retropubic midurethral sling procedure, the tension-free vaginal tape, and one of two transobturator midurethral sling procedures, the transobturator tension-free vaginal tape, which is placed starting inside the vagina and passing through the obturator foramen (“in-to-out”), or the Monarc, which is placed starting in the groin area, passing through the obturator foramen, and then into the vagina (“out-to-in”).6,7 A total of 597 women were randomized to receive either a retropubic (n=298) or a transobturator (n=299) midurethral sling. There were no significant differences in baseline characteristics between the two groups with respect to demographic characteristics, risk factors for UI, and severity of incontinence as measured by the Urogenital Distress Inventory, Incontinence Impact Questionnaire, Medical, Epidemiologic, and Social Aspects of Aging Questionnaire, pad test weight, and frequency of incontinence episodes.4 The mean Valsalva leak point pressure at baseline was slightly higher in the transobturator group, but there was no difference in the maximal urethral closure pressures.4 At 12 months postsurgery, both objective and subjective cure rates in the two procedures were determined to be equivalent.4
Patient satisfaction was measured 6, 12, and 24 months after surgery with the Incontinence Surgery Satisfaction Questionnaire, a 9-item self-administered questionnaire developed by the Urinary Incontinence Treatment Network for study of incontinence procedures.1,2 These items measure patient satisfaction with the result of surgery and are divided into three domains related to the following: bladder symptoms of leakage, urgency, and frequency; physical, social, and sexual activities previously restricted by UI symptoms; and emotions associated with their UI. Women responded based on a 5-point Likert-type scale with possible choices of 1 (completely dissatisfied), 2 (mostly dissatisfied), 3 (neutral), 4 (mostly satisfied), or 5 (completely satisfied). Summary scores for each domain were calculated by averaging the items in each respective domain. Additionally a composite summary score was generated from the combined average of all items. A dichotomous response variable was created (‘‘dissatisfied’’ compared with ‘‘satisfied’’) for each summary scale. A participant was coded as “dissatisfied” if her summary scale score was less than 4, and as “satisfied” if her summary score was 4 or more.
Participants also were asked whether they would choose to have the surgery again and whether they would recommend it to a friend. In addition, the Patient Global Impression of Severity and Improvement questionnaires were administered to gather information regarding women's overall appraisals of their conditions and their responses to treatment.8 The Patient Global Impression of Severity and Patient Global Impression of Improvement questionnaires have been shown to correlate significantly with incontinent episode frequency, pad test outcomes, and Incontinence Quality of Life Questionnaire measures.
Factors hypothesized to predict satisfaction with surgical outcomes included demographic characteristics, medical comorbidities, previous UI treatment, self-rated health, pelvic organ prolapse, type and severity of UI symptoms, UI symptom-related distress, quality of life, and patient expectations of surgery. Demographic, anthropomorphic, clinical, and urodynamic characteristics were recorded at baseline. Socioeconomic status was measured using the Nam-Powers Terrie Occupational Status Score.9 This measure assesses occupational status on the basis of educational requirements and expected salary with scores ranging from 0 to 100 (with higher scores indicating greater status). Self-assessment of overall health was determined using the Health Utilities Index measure of overall health, which yields scores ranging from 1 (excellent) to 5 (poor).10 Pelvic organ prolapse was assessed with the Pelvic Organ Prolapse Quantification System.
Expectations of surgery were assessed preoperatively by the Incontinence Surgery Expectation Questionnaire, a nine-item questionnaire developed by the Urinary Incontinence Treatment Network as a complement to the satisfaction survey.1 Women were asked to rate how much improvement in bladder symptoms, restrictions in physical, social, and sexual activities, and negative emotions they expected after recovery from surgery. Each item of this expectation questionnaire was graded on a 5-point Likert-type scale as 1 (no better), 2 (slightly better), 3 (somewhat better), 4 (much better), or 5 (completely better). For data analysis purposes, a dichotomous response variable was created (‘‘no better’’ compared with ‘‘much better’’), with ‘‘no better,’’ ‘‘slightly better,” and “somewhat better” responses combined to define ‘‘no better,’’ and ‘‘much better” and ‘‘completely better’’ responses combined to define ‘‘much better.”
Type of UI (stress compared with urgency) and severity were assessed at baseline and at 6, 12, and 24 months postoperatively with the Medical, Epidemiologic, and Social Aspects of Aging Questionnaire, 3-day bladder diary, 24-hour pad test, and a standardized provocative stress test.11,12 Standardized urodynamic testing also was administered at baseline to confirm urodynamic stress incontinence, to identify detrusor overactivity, and to quantify leak point and voiding pressures. The Medical, Epidemiologic, and Social Aspects of Aging questionnaire includes nine items regarding stress UI (SUI) symptoms and six regarding urgency UI (UUI) symptoms. Responses to stress and urgency items were summed to obtain a stress symptom score (range 0-27) and an urgency symptom score (range 0-18), with a higher Medical, Epidemiologic, and Social Aspects of Aging questionnaire symptom score indicating greater UI symptoms.
Condition-specific quality-of-life questionnaires were completed by women at baseline and then at 6, 12, and 24 months after surgery for comparison, and included the short forms of the Incontinence Impact Questionnaire and the Urogenital Distress Inventory.13,14 The Incontinence Impact Questionnaire assesses the effect of UI on everyday life, whereas the Urogenital Distress Inventory assesses the effect of UI on various activities, roles, and emotional states. Patient bother was measured by the subscales of the Urogenital Distress Inventory measuring SUI symptoms, urgency symptoms, and voiding symptoms. Adequate validity, reliability, and sensitivity to change have been reported by the authors.13,14
Complications and known side effects of surgery can dramatically affect patient satisfaction after treatment of quality-of-life disorders. Thus, such complications, especially recurrent urinary tract infection, intraoperative bleeding, voiding dysfunction, vaginal epithelium and bladder perforation, mesh exposure, UUI, and pain (beyond 6 weeks of surgery), were considered potential predictors of patient satisfaction. Adverse events were classified with a modified version of the Dindo classification system.15 A dichotomous response variable was created in which “adverse events” and “serious adverse events” were combined to define “complication” and compared with those of patients who had “no complication,” and it was used in bivariable and multivariable analyses.
Data were entered using a distributed data entry system and analyzed with SAS 9.2 software. Associations of categorical variables with categorical measures of satisfaction were evaluated by cross-classification and the χ2 of homogeneity or Fisher exact test. Associations of continuous variables with satisfaction were evaluated using logistic regression analysis. Variables significantly related to satisfaction in univariable analyses, along with clinically relevant variables, were entered into multivariable logistic regression models to test their independent association with satisfaction.
Of the 597 women enrolled and randomized, 527 completed satisfaction questionnaires at 12 months: 264 (88.6%) in the retropubic and 263 (88.0%) in the transobturator group. Both treatment groups experienced high levels of satisfaction (Table 1), with 85.9% (225 of 262) in the retropubic and 90.0% (235 of 261) in the transobturator group reporting that they were either “mostly” or “completely” satisfied with respect to urine leakage, with no significant difference between the two routes of surgery (P=.52). The majority of patients were highly satisfied with respect to other measures on the questionnaire, specifically with urgency to urinate, frequency of urination, capability of physical activity, social activity, ability to engage in sexual activity, and from an emotional standpoint (Table 1) with no significant difference between the two procedures. Additionally, more than 95% of participants in both sling groups indicated that they would still choose to have the surgery or recommend it to a family member or friend if they could go back in time with the knowledge and experience they acquired after the surgery.
The summary scores for each domain (symptom, activity, emotion) and the composite satisfaction summary score were compared for both routes of surgery (Table 2). There were no significant differences between the retropubic and the transobturator approaches. The rates of satisfaction were essentially unchanged between 12 and 24 months postsurgery (data not shown), so we have presented the analysis of the 12-month follow-up only.
Baseline characteristics associated with reduced satisfaction were higher Medical, Epidemiologic, and Social Aspects of Aging questionnaire urgency subscale scores, detrusor overactivity, and diabetes mellitus (Table 3). There was no difference in proportion of participants who were satisfied and those who were not satisfied when the lower quartiles of the Valsalva leak point pressure or maximal urethral closure pressure values were examined. The severity of incontinence at baseline, both objective (as measured by incontinence episode frequency, pad test weight) and subjective (as measured by Incontinence Impact Questionnaire and Urogenital Distress Inventory score), was not statistically different between satisfied and unsatisfied patients. Patients' perception of preoperative global severity of incontinence and having a postoperative expectation of cure or being “completely better” did not alter the proportion of patient satisfaction between the two routes of surgery.
Not surprisingly, patients who were “mostly” or “completely satisfied” 12 months after midurethral sling placement were those who had fewer daily incontinence episodes, lower pad weights, lower scores on the Incontinence Impact Questionnaire and Urogenital Distress Inventory, greater improvement in the stress and urgency subscale of the Medical, Epidemiologic, and Social Aspects of Aging questionnaire, reported improvement on the Patient Global Impression of Improvement questionnaire, experienced more overall treatment success, and had fewer complications. Patients who had less nocturia and less frequency of voids also were more satisfied (Table 3).
On univariable analysis, additional factors that appear to have influenced patients' perceptions of satisfaction were the amount of change in certain clinical variables they experienced from baseline presentation. Specifically, greater improvement in incontinence episode frequency, nocturia, voiding frequency, pad test weight, both stress and urgency subscales on the Medical, Epidemiologic, and Social Aspects of Aging questionnaire, and scores on the Incontinence Impact Questionnaire and Urogenital Distress Inventory all were associated with greater levels of satisfaction 12 months after sling placement. Additionally, patients who were more satisfied had fewer complications overall and a lower proportion of severe adverse events.
In the final multivariable model (Table 4), patient satisfaction after midurethral sling was associated with overall treatment success, lower baseline Urogenital Distress Inventory scores, and decrease in Urogenital Distress Inventory and Incontinence Impact Questionnaire scores. Patient satisfaction also was associated with fewer complications at 12 months, although this relationship had borderline statistical significance (P=.05).
The results of this analysis show that the majority of women who underwent midurethral sling surgery were “mostly” or “completely” satisfied with their improvement in incontinence symptoms 1 year after surgery. Significant improvement of other lower urinary tract symptoms, such as urgency and frequency, were reported by most participants as well. Satisfaction with symptom improvement was associated with both objectively measured and patient-perceived improvement of stress incontinence and fewer complications. In addition, incontinence severity and urodynamic parameters at baseline did not predict postoperative satisfaction.
Although there are increasing numbers of randomized trials comparing the efficacy of various SUI surgeries, there are relatively little data regarding patient satisfaction. Initial studies of incontinence treatments focused on objective outcomes, such as urodynamic measures and incontinence episodes, to define success. However, it has become apparent that patient-perceived success and satisfaction are important dimensions to include to consider the broader effect of surgery on daily function, de novo pelvic floor symptoms,16 or postoperative healing.17 We believe our study supplements the literature on satisfaction with surgical treatment of SUI. Besides examining satisfaction in two additional procedures, more importantly, the study provides data for a number of different aspects of satisfaction and for which domain of satisfaction is altered by surgery. There are multiple components that can contribute to patient satisfaction; how these change in response to therapy may not be evident from studying a single item that only asks whether the patient is satisfied.2 Patient-centered outcomes are increasingly recognized as we move forward with comparative effectiveness trials for pelvic floor disorders. Accordingly, assessing patient impression of severity and perceived improvement, we found that patients' global impressions of improvement after SUI surgery were highly predictive of being “mostly” or “completely” satisfied.
Patients had high expectations at baseline that SUI surgery would cure or greatly improve urine leakage and resolve urinary urgency, frequency, as well as incontinence-related issues with sexual activity and embarrassment. One might theorize that failure of the stress SUI procedure to resolve all of these symptoms would result in greater patient dissatisfaction. We did not find that women's preoperative expectations affected satisfaction with midurethral sling surgery, perhaps because most women reported they were “mostly” or “completely” satisfied with improvement in these symptoms and therefore considered their surgery to be successful. In cases like these in which surgical procedures result in such symptom improvement, the level of satisfaction may be so high that differences are difficult to discern because of a ceiling effect. One of the important limitations of the current study is the potential bias of measuring satisfaction with treatment in a large clinical trial setting. With increased number of contacts and communications between participants and members of the research team, coupled with the tendency of participants to not report dissatisfaction with a treatment outcome, the perception of satisfaction may be inflated.18–20
Our findings that greater reduction in SUI symptoms and symptom bother were associated with patient satisfaction are consistent with predictors of patient satisfaction in the SISTEr population.2 However, the SISTEr trial also found that patients with greater UUI symptoms at baseline and detrusor overactivity at 24 months had lower odds of being satisfied with their surgical outcomes. This contributes to an emerging body of literature describing the effects of preoperative UUI on SUI surgery outcome. The majority of authors have reported that greater baseline UUI symptoms predict increased odds of failure and lower patient satisfaction after SUI surgery, suggesting that patients with mixed UI having a significant UUI component should be counseled accordingly.2,16,21,22 Although we found that higher baseline Medical, Epidemiologic, and Social Aspects of Aging Questionnaire urgency scores were associated with less post-operative patient satisfaction in the univariable analysis, this association did not persist in the final multivariable model.
Complications also predicted lower patient satisfaction. Although de novo or worsening overactive bladder symptoms may independently predict SUI surgery failure and dissatisfaction, Davis et al23 showed that the need for a sling release in the early postoperative period (less than 6 weeks) was the factor most predictive of dissatisfaction 1 year after a tension-free vaginal tape sling, even if patients remained continent. Others have shown that postoperative complications, detrusor overactivity, and urinary retention were associated with overall dissatisfaction.16
Our study findings are strengthened by the study design, a multicenter comparative effectiveness trial with diverse surgeons from both urology and urogynecology, which limits potential bias and contributes to the generalizability of the results. Although extensive preoperative clinical and demographic data were collected, as well as validated objective and subjective outcome measures, there are other factors that could affect satisfaction such as patient preparedness and goal achievement that were not assessed. Nonetheless, the use of patient expectations and patient-perceived improvement measures to predict satisfaction emphasizes the importance of including patient-reported outcomes along with more traditional objective measures of improvement when assessing SUI treatment outcomes.
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