One hundred and two women with urodynamic SUI who underwent treatment at our departments from January 2008 to April 2012 were enrolled in this study. Standardized assessment was performed at enrolment, taking into consideration a comprehensive urogynecological history, urodynamic assessment including uroflowmetry and cystometry, bacteriological examination, and pad tests. The protocol was previously approved by the Bioethical Committee of the Medical University of Bialystok (R-I-002/143/2009), and all women gave their written consents.
Major exclusion factors were patients with chronic degenerative diseases that would affect muscular and nerve tissues, presence of any degree of pelvic organ prolapse (POP), active or recurrent urinary tract infections (UTI), vulvovaginitis, atrophic vaginitis, diabetes mellitus, neurological disease, psychiatric illness, use of medication affecting micturition, history of surgical or pharmaceutical treatment of SUI, chronic debilitating disease such as renal failure, and those with cardiac pacemakers. We also excluded patients with intrinsic sphincteric deficiencies identified by the Valsalva leak-point pressure ≤60 cm
0 measurement in the sitting position with a volume of 250 ml in the bladder and/or a urethral closure pressure ≤20 cm
0 in the sitting position at maximum cystometric capacity.
Participants were taught skills and strategies for preventing incontinence and suppressing urge. This included education about normal bladder control, lifestyle interventions such as weight reduction, relieving constipation, smoking cessation, caffeine reduction, fluid management, wearing nonrestrictive and easily removed clothing, reducing emotional stress, and correcting faulty habit patterns of frequent urination by suggesting distraction and avoidance techniques. Advice on good voiding position was also provided. In addition, an information booklet was provided to reinforce this information.
The severity of UI can be assessed by various methods, such as a urinary symptoms questionnaire, frequency/volume chart (bladder diary), QOL questionnaire, or pad tests. A 7-day bladder diary provides the means for assessing voiding frequency and volume, together with the frequency of leaks at 0, 8, and 16 weeks.
During initial examination, a POP and pelvic floor dysfunction assessment was performed, as previously described, with the patient supine and after voiding [18
]. Assessment of pelvic floor muscle strength was performed with vaginal palpation; the woman in the lithotomy position used one finger with the two distal phalanges inside the introitus vagina. One gynecologist per department should examine and palpate the external and internal vaginal and rectal muscles for function, pain, strength, coordination, and endurance for standardizing the methodology. The effort was graded with the Oxford score (0 nil; 1 flicker; 2 weak; 3 medium, with slight lift of the examiners finger and no resistance; 4 strong, sufficient to elevate the examiner’s finger against light resistance; 5 very strong, sufficient to elevate the examiner’s finger against strong resistance) [5
Next, the bladder was drained to obtain a postvoid residual, and the s bladder was then retrograde filled to a volume of 300 ml or maximal capacity (if that occurred prior to 300 ml). The patient was then cued to cough and perform a Valsalva maneuver while supine. If no urine leakage was observed, the patient was asked to perform the same maneuvers while standing. The cough stress test was considered positive if any leakage was noted with cough or Valsalva [19
Uroflowmetry (Ellipse Andromeda System, Germany) was performed on all participants. Each participant was asked to attend the session with a comfortably full bladder to perform a free-flow uroflowmetry. In order to carry out the test, it was necessary to gain an artificial standardized fill of 250 ml using a size-12 Foley urethral catheter at a maximum filling rate of 20 ml per minute. After emptying the patient’s bladder with a catheter, the 20-min pad test by infusion of 250 ml distilled water in the bladder was performed after the urodynamic study. Each patient returned to a standing position, with a preweighed perineal pad placed inside the underwear. Each patient was asked to cough ten times, bear down ten times, do ten deep knee bends, jump up and down in place ten times, wash her hands under cold water for 1 min, walk up and down five stairs ten times, walk in the hall for 10 min, and then return for removal of the pad (Bella Sp. z o.o., Torun, Poland). The pad was then weighed, and the net weight was calculated by subtracting the original dry weight to achieve a measure of the total urine lost during the 20-min exercise. A pad weight result was considered positive if a leakage >1 g was noted; pads were weighed on a precision laboratory balance Acculab VI-1200 (Bradford, MA, USA) [20
Patients with urodynamically confirmed SUI were randomized using a computer-generated random sequence given in sealed envelopes to patients in group 1 [active (n
68)] or group 2 [placebo (n
34)] TVES with sEMG-assisted biofeedback. In a previous study with 24 patients, the final sample size was calculated as 102 patients for a power of 80 % and a 2:1 ratio (68 and 34, respectively). Patient distribution was chosen to better evaluate the proposed technique. One hundred and nineteen individuals were screened for eligibility: 107 were eligible, five of whom withdrew before completion of assessments. Thus, 102 were recruited. Group assignment was enclosed in sequentially numbered, sealed envelopes by a person not involved in the study. The physiotherapist and physician carrying out the assessment were unaware of which treatment group the patient was in. To minimize the likelihood of assessor bias, participants were asked not to discuss their treatment and/or reveal any information on group allocation to the principal investigator doing the assessments. Participants were scheduled to attend clinic visits. All interventions were performed by gynecologists and competent physiotherapists. Screening, outcome assessments, and weekly visits were carried out at hospital sites offering identical facilities.
In group 1 TVES, was provided with the addition of sEMG biofeedback. EMG records muscle bioelectrical activity and measures electrical correlation of the muscle contraction. Vaginal and surface electrodes can be used to provide an overview of the contraction and relaxation phases of pelvic floor muscle activity. EMG biofeedback assessment used a NeuroTracTM ETS unit (Verity Medical Ltd, Hampshire, UK). A vaginal electrode, VeriProbe (Verity Medical), was applied according to the manufacturer’s instructions with Zelpol lubricating couplant (Centrum Medicum, Poland), and stimulation parameters and patient-acceptable sensitivity thresholds were determined. The device combines biofeedback and (ES), with effective monitoring of compliance with treatment and performance. Patient position, accuracy of electrode placement, exact warmup period, and time of day were all recorded. The regimen included a warmup of five contractions and five relaxations, followed by a contraction/relaxation assessment. Participants were encouraged to selectively contract and relax their pelvic floor muscles with the assistance of visual and auditory feedback.
Patients in group 1 were provided with active TVES with sEMG. Parameters of muscle stimulation were adapted for each participant: frequency ranged from 10 to 40 Hz, impulse width from 200 to 250 μs, and runtime/decontraction in configuration of 15 s/30 s for 20 min. The treatment lasted for 8 weeks and was performed twice a day. The introduction took place in the clinic, and the actual treatment was performed by patients at home, with a gradual increase to a daily maximum of 40 min. At each weekly visit, compliance was monitored by means of a concealed button on the NeurotracTM ETS unit, and the unit was reprogrammed weekly, as appropriate.
Participants in group 2 were provided with a placebo set to parameters proven to have no physiological effect. The same type of electrode and hand-held unit as described for TVES with sEMG biofeedback was used in the clinic and for home application. Preset parameters were a frequency of 2 Hz, a pulse width of 50 μs, 2 s of stimulation, and 60 s of no stimulation, with a ramp of 8 s. As with group 1, the introduction took place in the clinic, and patients used issued devices at home, with a gradual increase to a daily maximum of 40 min. Treatment continued until participants had completed 8 weeks with the assigned device. At this point, a posttreatment assessment identical to the intake assessment was performed. Participants underwent three 24-h pad tests using Bella Normal sanitary pads. For each test (week 0, 8, and 16), five pads each contained in their own sealable plastic bag were weighed and given to participants. Women were asked to wear the pads for 24 h: one pad at a time for a maximum of 6 h except for the pad worn during the night’s sleep, which could be worn all night. After usage, the pad, its wrapper, and adhesive strips were returned to their plastic bag and sealed to prevent evaporation. The two pad tests were to be completed within a week and returned to the clinic within the following week prior to initiation of the new treatment. The pads were reweighed, and the urine lost during each 24-h period was calculated. If the wrapper and adhesive strips were not returned, pad weight results were adjusted to account for their weight. Pre- and postpad weights were determined using the same beam balance scales with accuracy to 0.1 g. The 24-h pad test was considered positive if a weight exceeded 8 g [19
All study participants were also asked to complete the validated Incontinence Quality of Life (I-QOL) questionnaire containing one section. A score of 100 represented the best possible QOL, and 0 represented the worst possible QOL. Valid and reliable outcome measures were recorded at weeks 0 (baseline), 8, and 16. The I-QOL contains 22 negatively framed items, each with a five-point Likert-type response scale (1 extremely, 2 quite a bit, 3 moderately, 4 a little, 5 not at all). The I-QOL was scored according to the instructions [22
]. In addition to yielding a total score, the I-QOL consists of the following three domain scores: avoidance and limiting behaviors (eight items), psychosocial impacts (nine items), and social embarrassment (five items). The I-QOL total and subscale sum scores are transformed onto a 0–100 scale for greater interpretability, with the higher scores representing greater QOL. Once the I-QOL was scored and plotted, variations in mean scores were noted across the language versions [23
Statistical analysis was performed using Statistica software version 9.0PL (StatSoft, Inc., StatSoft Polska Sp. z o.o., Poland). A chi-square test was used to evaluate the relationship between categorical variables. Fisher’s exact test was used to determine significance between groups. The Mann–Whitney U test was used for comparison of continuous variables between groups. Comparisons within each group were carried out using the Wilcoxon signed rank test. A p value < 0.05 was considered statistically significant.