Context.— Urinary incontinence is a common condition
caused by many factors with several treatment options.
Objective.— To compare the effectiveness of
biofeedback-assisted behavioral treatment with drug treatment and a
placebo control condition for the treatment of urge and mixed urinary
incontinence in older community-dwelling women.
Design.— Randomized placebo-controlled trial conducted from
1989 to 1995.
Setting.— University-based outpatient geriatric medicine
clinic.
Patients.— A volunteer sample of 197 women aged 55 to 92
years with urge urinary incontinence or mixed incontinence with urge as
the predominant pattern. Subjects had to have urodynamic evidence of
bladder dysfunction, be ambulatory, and not have dementia.
Intervention.— Subjects were randomized to 4 sessions (8
weeks) of biofeedback-assisted behavioral treatment, drug treatment
(with oxybutynin chloride, possible range of doses, 2.5 mg daily to 5.0
mg 3 times daily), or a placebo control condition.
Main Outcome Measures.— Reduction in the frequency of
incontinent episodes as determined by bladder diaries, and patients'
perceptions of improvement and their comfort and satisfaction with
treatment.
Results.— For all 3 treatment groups, reduction of
incontinence was most pronounced early in treatment and progressed more
gradually thereafter. Behavioral treatment, which yielded a mean 80.7%
reduction of incontinence episodes, was significantly more effective
than drug treatment (mean 68.5% reduction;
P=.04) and both were more effective than the
placebo control condition (mean 39.4% reduction; P<.001 and
P=.009, respectively). Patient-perceived
improvement was greatest for behavioral treatment (74.1% "much
better" vs 50.9% and 26.9% for drug treatment and placebo,
respectively). Only 14.0% of patients receiving behavioral treatment
wanted to change to another treatment vs 75.5% in each of the other
groups.
Conclusion.— Behavioral treatment is a safe and effective
conservative intervention that should be made more readily available to
patients as a first-line treatment for urge and mixed
incontinence.
URINARY INCONTINENCE is a prevalent and costly
condition that affects approximately 38% of older community-dwelling
women (age ≥60 years).1 Incontinence predisposes patients
to other health problems, contributes to depression and social
isolation, is a significant source of dependency among the elderly, and
is widely cited as a factor in nursing home admissions.2
The costs of incontinence are enormous, accounting for an estimated $16
billion each year.3 Urge incontinence, the involuntary
urine loss associated with a strong sensation to void, is especially
common among older women and is usually associated with detrusor
instability or reduced bladder capacity. It is often characterized by
sudden large-volume urinary accidents that can lead to embarrassment
and significant restriction of activities.
Urge incontinence is commonly treated with drugs that
inhibit detrusor contraction. In addition to pharmacological
approaches, behavioral treatments have been shown to improve bladder
control by teaching patients new skills or habits.4-14
Biofeedback-assisted behavioral training is a form of behavioral
treatment that reduces incontinence by teaching patients how to control
the physiologic responses of the bladder and pelvic muscles
that mediate continence.4,5,15-18 Combined
bladder-sphincter biofeedback has been used to teach patients to
inhibit detrusor contractions and increase intraurethral pressure in
the treatment of urge incontinence.8-10,12,14,19
The present study is the first randomized clinical trial comparing the
effectiveness of biofeedback-assisted behavioral treatment with both a
standard drug treatment (oxybutynin chloride) and a control condition
for the treatment of urge incontinence. In addition to testing the
effectiveness of behavioral treatment, it is important to compare
behavioral and drug treatment because the 2 interventions are both
viable options with distinct advantages and disadvantages that need to
be considered in clinical decision making.
Subjects were older, community-dwelling women with urge incontinence.
They were recruited through local advertisements and professional
referrals and screened by telephone for eligibility. Subjects had to be
at least 55 years of age, be ambulatory, and describe urge incontinence
occurring at least twice per week and persisting for at least 3 months.
Informed consent procedures approved by the university institutional
review board were followed. The study was conducted between July 1,
1989, and August 30, 1995.
Potential subjects who met initial criteria were scheduled for a
clinical evaluation to identify those who were not appropriate for
treatment with oxybutynin or behavioral methods. The
evaluation consisted of a patient's continence and medical history
and a physical examination; postvoid catheterization for residual
urine; urodynamic evaluation; determination of electrolyte levels,
serum urea nitrogen, and creatinine; and urinalysis. In addition, the
Mini-Mental State Examination (MMSE)20 was used to screen
for dementia.
In cases of urinary tract infection (urine colony count,
≥10,000), fecal impaction, severe atrophic vaginitis, or a
correctable metabolic problem, subjects were offered treatment and
reconsidered at a later date. When hematuria was present on urinalysis,
the decision to enroll the subject was based on urologic consultation.
Urodynamic testing consisted of 2-channel supine water cystometry
using a No. 12 Foley catheter, a rectal balloon, and a filling rate of
50 mL/min. Threshold volumes were recorded for first desire to
void, strong desire to void, detrusor contraction,
cystometric capacity, and urine loss. With the urinary catheter
removed, maneuvers were performed to provoke urge or stress
incontinence: positional changes (lying to sitting, sitting to
standing), coughing (4 times while lying and standing),
listening to running water while standing (20 seconds), washing hands
in running water (20 seconds), heel bouncing (4 times), and walking to
the toilet. The purpose of the testing was to document bladder
dysfunction (inclusion criterion) and to classify the type of
incontinence for stratification.
Subjects were provided with 2 weeks of bladder diary booklets to
document the time of every void and incontinent episode, the volume of
urine loss (large or small), and the circumstances of each episode. The
main purpose of the diary was to document pretreatment frequency
of incontinence.
Inclusion and Exclusion Criteria
To be included, subjects had to have at least 2 urge accidents per week
on the 2-week baseline bladder diary, and urge incontinence had to be
the predominant pattern (the number of urge accidents had to exceed the
number of stress accidents). Also, there had to be urodynamic evidence
of bladder dysfunction (detrusor instability during filling or
provocation or maximal cystometric capacity of ≤350 mL).
Subjects were excluded if they had continual leakage, postvoid
residual urine volume more than 200 mL, uterine prolapse past the
introitus, narrow-angle glaucoma, unstable angina, decompensated
congestive heart failure, history of malignant arrhythmias, or impaired
mental status (MMSE score <20).
The study was a randomized placebo-controlled trial. Following
enrollment, subjects were stratified by type and severity of
incontinence. Baseline bladder diary and urodynamic test results were
used to classify incontinence as "urge only" or "mixed stress and
urge." To ensure between-group comparability on pretreatment severity
of incontinence, the baseline bladder diary was used to stratify
subjects as having mild (<5 episodes per week), moderate (5-10
episodes per week), or severe (>10 episodes per week)
incontinence. Within each stratum, randomization was performed
with computer-generated random numbers using a block size of 6 to avoid
inequity in group size. Subjects were randomly assigned to behavioral
treatment, drug treatment, or a placebo control condition.
For all subjects, treatment consisted of 4 clinic visits at
2-week intervals during an 8-week period. Subjects completed a daily
bladder diary throughout treatment. At each visit, bladder diaries were
reviewed by clinic staff to ensure that entries were clear and
interpretable. Vital signs were recorded and a urine specimen was
collected. Anal sphincter pressure was measured using manometry.
An adverse effects checklist was completed, which consisted
of 5 known adverse effects of oxybutynin (inability to void,
confusion, dry mouth, blurred vision, constipation)
intermeshed with "dummy" symptoms. Interventions were implemented
by nurse practitioners. The control group was intended to control not
only for the placebo effect but also for the effects of clinic visits,
self-monitoring (bladder diary), and therapist contact.
Behavioral Training.— During clinic visits, patients in the
behavior group were taught skills and strategies for preventing
incontinence and provided with instructions for daily home practice. In
visit 1, anorectal biofeedback was used to help patients identify
pelvic muscles and teach them how to contract and relax these muscles
selectively while keeping abdominal muscles relaxed. Visit 2 was
devoted to teaching patients how to respond adaptively to the sensation
of urgency ("urge strategies").21 Instead of rushing to
the toilet, which increases intra-abdominal pressure and exposure to
visual cues that can trigger incontinence, subjects were encouraged to
pause, sit down if possible, relax the entire body, and contract pelvic
muscles repeatedly to diminish urgency, inhibit detrusor contraction,
and prevent urine loss. When urgency subsided, they were to proceed to
the toilet at a normal pace. In visit 3, pelvic muscle biofeedback was
repeated for subjects who had not achieved at least a 50% reduction
in frequency of accidents as documented on bladder diary.
Combined bladder-sphincter biofeedback was used to teach patients to
contract pelvic muscles against increasing volumes of fluid, in the
presence of increasing urgency, and during detrusor contraction (Figure
1). Visit 4 was used to review progress,
"fine-tune" home practice, and encourage persistence.
Home practice included 45 pelvic muscle exercises every day (15
exercises, 3 times per day). Duration of individual contraction and
relaxation was based on the ability demonstrated by each patient in the
biofeedback session and gradually increased across sessions to a
maximum of 10 seconds each. Patients were advised to practice in
various positions, including lying, sitting, and standing. They were
encouraged to contract pelvic muscles during activities that commonly
resulted in incontinence. Finally, patients were instructed to practice
interrupting or slowing the urinary stream during voiding once per day.
Drug Treatment and Control Condition.— Assignment to drug treatment or the placebo control condition was double-blinded, so all
patients in these groups were managed as if they were taking
oxybutynin. The protocol was initiated at 2.5 mg of oxybutynin chloride
3 times daily, half the usual recommended adult dosage. Oxybutynin and
placebo were dispensed in identical capsules containing 500
mg of riboflavin phosphate as a marker. Clinic visits were also
used to review bladder diaries, monitor progress, manage
adverse effects, and make dosage adjustments using a minimum dosage of
2.5 mg/d and a maximum of 5.0 mg 3 times daily. The goal during the 8
weeks was to stabilize the patient taking the most effective dose she
could tolerate long-term while controlling adverse effects and avoiding
dropout. The protocol was flexible to be comparable with actual
clinical practice.
Following treatment, subjects completed 2 weeks of posttreatment
bladder diaries and returned to the clinic to complete a final urine
specimen, adverse effects checklist, cystometrogram, and patient
satisfaction questionnaire administered by the nurse practitioner.
Subjects were asked to describe their progress (much better, better,
about the same, or worse), satisfaction with progress (completely,
somewhat, or not at all satisfied), and perceived improvement
(estimated percent improvement, 0% [none] to 100% [dry]).
Patients also reported whether they were comfortable enough with
treatment to continue indefinitely (yes or no) and whether they wished
to receive another form of treatment (yes or no).
Data Management and Analysis
The 3 treatment groups were first compared using
χ2 tests and analysis of variance (ANOVA) to determine
whether differences existed between the groups on key variables prior
to treatment. The primary outcome measure was reduction in the
frequency of incontinent episodes as derived from bladder diaries. A
research assistant, blinded to treatment group, scored bladder diaries
and managed the data. The pretreatment and posttreatment frequencies of
incontinence were used to calculate a percentage reduction for each
subject (0%, no improvement; 100%, totally dry). Mean
reductions were analyzed using a rank-based ANOVA
procedure22 (to accommodate the nonnormality of the data)
and post-hoc comparisons (Duncan multiple range tests using an overall
α level of .05).22,23 χ2 Analysis
was used to compare the groups on the categorical outcome measures.
These analyses were computed using SPSS (SPSS Inc, Chicago, Ill) and
SAS (SAS Institute Inc, Cary, NC) software, and when cell sizes did not
permit a valid use of the χ2 statistic, the
STATXACT software package.24 The analysis was based
on intention-to-treat and thus included all subjects.
When subjects did not complete treatment, calculation of improvement
was based on the most recent bladder diaries.
Of 468 women who were evaluated clinically, 271 were ineligible or did
not participate (Table 1), and 197 (ages 55-92
years) were randomized (Figure 2). Characteristics
of the subjects are presented in Table 2. Before
treatment, the groups were comparable on all key parameters except that
subjects in behavioral treatment had more children, were less likely to
have a high school education, and more likely to have a rectocele.
In the behavioral treatment group, 73.8% (n=48) of
subjects received a single session of anorectal biofeedback. Another
9.2% (n=6) underwent a second training session of
anorectal biofeedback because of uncertainty about correct muscle
contraction. The remaining 16.9% (n=11) had a second
session in which combined bladder-sphincter biofeedback was used. No
patients received more than 2 sessions of biofeedback.
In drug treatment, dosage was individually titrated. The final
dosages ranged from 2.5 to 15.0 mg/d as follows: 2.5 mg (7.5%), 5.0 mg
(19.4%), 7.5 mg (24.4%), 10.0 mg (17.9%), and 15.0 mg (26.9%).
During treatment, 2 adverse effects, dry mouth and inability to
void, distinguished the intervention groups (Table
3). The drug therapy group reported a significantly
higher incidence of dry mouth (P<.001) and inability to void
(P=.002) than did the control group. In
addition, the behavioral group had even less dry mouth than the control
group (P=.03).
The attrition rate was 6.2% in the behavioral group, 17.9% in drug
treatment, and 18.5% in the control condition. Seven patients (Figure
2) dropped out before a follow-up bladder diary could be completed so
190 patients were included in the analysis.
Before treatment, frequency of incontinence was similar across
the 3 groups (Table 4). After treatment, the groups
were significantly different with the highest frequency of incontinence
reported in the control group and the lowest in the behavioral group
(P=.005). Behavioral training, which resulted
in a mean 80.7% improvement, was
significantly more effective than drug treatment (mean,
68.5% improvement; P=.04) and the control
condition (mean, 39.4% improvement; P<.001). In addition,
the drug treatment was more effective than the control condition
(P=.009).
Similarly, a larger proportion of subjects in the behavioral
group achieved at least 50% and 75% reductions of incontinence
(P=.002, P<.001; Figure
3). Although the values for full recovery of
continence (100%) followed a similar pattern, the
differences were not statistically significant
(P=.07). In addition, it is noteworthy
that some patients had more accidents after treatment than before (1
[1.6%] of 63 in behavior treatment, 3 [4.6%] of 65 in drug
treatment, and 10 [16.1%] of 62 in the control condition).
Figure 4 displays the mean frequency of
incontinence across time. In all groups, reduction of
incontinence was most pronounced early in treatment and
progressed more gradually thereafter.
Patient Satisfaction and Comfort
Several secondary outcome measures were used to assess the patient's
perceptions of treatment (Table 5). On every
parameter, the behavioral group reported the highest perceived
improvement and satisfaction with treatment progress
(P<.001). Of particular interest are the findings that
96.5% of the behavior group reported being comfortable
enough with the treatment to continue indefinitely, while only 14.0%
wished to receive another form of treatment. Despite the beneficial
effects of drug treatment, only 54.7% said they could continue
indefinitely and 75.5% said they wished to receive another form of
treatment. Subjects who were not completely dry in the 2-week
posttreatment period were invited to enter combined treatment. In the
behavioral group, 14.5% wished to add drug treatment to their regimen,
while 53.3% of those in the drug group wished to receive behavioral
treatment.
Fifty-three percent of subjects (105/197) completed posttreatment
cystometrogram. This subsample of subjects with
complete pretreatment and posttreatment urodynamic data were compared
with the remaining subjects on outcome (number of accidents) and all 17
baseline characteristics reported in Table 2. The groups did not differ
significantly for any variable except that subjects in the subsample
were less likely to have atrophic mucosa (35% vs 48.9%;
P=.05). Bladder capacity increased by a mean
of 17.3 mL in the behavioral group (P=.30) and
70.9 mL in the drug group (P<.001), and decreased by a mean
of 5.9 mL in the placebo group (P=.61).
This study is the first randomized clinical trial of
biofeedback-assisted behavioral treatment for urge incontinence and the
first to compare this therapy with a standard pharmacological
treatment. The results of this clinical trial show clearly that
biofeedback-assisted behavioral training is an effective and acceptable
conservative treatment for urge incontinence. It was more effective
than oxybutynin, the pharmacological agent of choice for urge
incontinence, and it is safe, yields high levels of patient
satisfaction, and is practical for older individuals. The mean 80.7%
reduction of incontinence achieved is similar to that of previous
studies of bladder-sphincter biofeedback and was obtained with a less
intensive approach than has been described in earlier
reports.8-10,12,19 In previous studies, most subjects were
catheterized to provide bladder pressure biofeedback and in most cases
they were reinstrumented. The present study tested a staged
approach in which anorectal biofeedback was used alone in 1 session and
only repeated or combined with bladder pressure biofeedback in subjects
whose initial response was unsatisfactory. Most subjects in this study
(73.8%) required a single biofeedback session. This suggests that the
pelvic muscles were usually identified properly in a single visit,
requiring less repetition of biofeedback than was previously thought to
be necessary.
In the previous literature on urge incontinence, a form of
bladder training is described in which bladder habits are altered
through specified voiding schedules and techniques for postponing
urination.6,7,13 Pelvic muscle training and exercise are
generally reserved for the treatment of stress
incontinence.15,16,25,26 In the present study, pelvic
muscle training and exercise were the primary components in the
treatment of urge incontinence. The results support the concept that
learned pelvic muscle contractions can prevent urine loss by inhibiting
and aborting detrusor contraction (Figure 1).
Behavioral intervention has the advantage that incontinence can be
reduced without the adverse effects that are common with
pharmacological intervention. A total of 96.5% of patients reported
being comfortable enough with behavioral intervention to continue it
indefinitely. Most subjects were completely satisfied with their
progress, and few wished to receive an alternate form of treatment.
Little is known, however, of the long-term durability of the treatment
and how well patients can sustain treatment adherence. A limitation of
the behavioral treatment is that it depends on the active
participation of a motivated patient, indicating that its value may be
limited in individuals with cognitive impairment or those with less
motivation.
An advantage of drug treatment is that it demands little effort from
the patient; thus, it is attractive to many patients. The cystometric
data on bladder capacity suggest that increased bladder capacity could
be a mechanism for successful treatment with oxybutynin. Another
advantage is that it requires less clinician time. However, it should
be noted that the 68.5% mean improvement in this trial reflects
multiple visits and more clinician time than might ordinarily be spent
to prescribe medication. This study optimized effectiveness with the
follow-up visits, careful management of adverse effects, and
individualized dosage titration during a period of 8 weeks. In addition
to optimizing drug therapy, it was also important, for the sake of
design validity, to keep the number of visits and amount of therapist
contact as constant as possible across the 3 intervention groups. The
results are based on an intention-to-treat analysis, but the data are
derived from the last diaries available and therefore reflect a period
during which dropouts were still taking their medication. Despite
improvement with medication, 10.4% of subjects were unwilling or
unable to continue oxybutynin treatment due to adverse effects.
The significant improvement achieved by the control group (mean,
39.4% reduction) is worth noting. The control condition should not be
interpreted as a no-treatment condition, since like the other groups,
they were active participants in treatment. Control patients consumed
capsules that they knew could have contained the medication, completed
detailed bladder diaries throughout the 8-week intervention phase,
attended 4 clinic visits, completed an adverse effects checklist at
each visit, and received therapeutic attention from a nurse
practitioner who reviewed the diaries with them and inquired about
their progress and concomitant events.
Thus, in addition to the placebo effect, attention, interaction, care,
expectations of improvement, and mobilization of patient effort could
have contributed to therapeutic outcome. In addition, close
self-monitoring by bladder diary can enhance awareness of bladder
habits and leakage patterns and may reduce incontinence by giving the
patient insights into behavioral alterations that can decrease urge
accidents. No doubt any or all of these components could have
contributed to improvement in all 3 groups and could account for the
significant improvement of the control group. Because these effects
were thought to be significant in previous studies, the control group
in this study was intended to control for these possible nonspecific
effects so that the unique effects of behavioral intervention and drug
therapy could be determined. Similar control group effects have been
reported in previous clinical trials of medication for urge
incontinence.27,28
One limitation inherent in this trial is that it was not possible
to blind the patients or the nurses regarding assignment to behavioral
vs drug treatment. However, the research assistant who scored the
outcome measures was kept blinded. Another possible limitation is the
reliance on the bladder diary as the primary outcome measure. Accuracy
of self-report data is always a matter of concern; however, the bladder
diary has been found to be a reliable method of evaluating frequency of
urine loss.29 Compared with urodynamic testing, the diary
is perhaps less objective, yet we would assert that it is a more
clinically relevant measure in that it documents incontinence in vivo
during a considerably longer period.
The role of behavioral treatment was addressed at the National
Institutes of Health–sponsored Consensus Conference on Urinary
Incontinence in Adults.30 The consensus panel recommended
that the least invasive or dangerous procedures should be tried first,
and that for many forms of incontinence, this criterion is met by
behavioral treatments. Behavioral treatment has also been recommended
as a first-line treatment in the Clinical Practice Guideline for
Urinary Incontinence developed under the auspices of the Agency for
Health Care Policy and Research.3 Previous studies by our
group and others have demonstrated that the behavioral procedures
described in this article are practical and can be implemented
effectively by nonphysician providers in outpatient office
settings.10,11,14 A behavioral intervention with these
characteristics has the potential for widespread application.
Currently, drug treatment is readily available and widely used. The
results of this study indicate that behavioral treatment should also be
made more available and offered routinely as an option for first-line
treatment for urge incontinence.
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