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Journal of International Medical
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Consolidation therapy is necessary following successful biofeedback treatment for
pubertal chronic prostatitis patients: a 3-year follow-up study
Jun Wang, Lin Qi, Xiang Yang Zhang, Yuan Qing Dai and Yuan Li
Journal of International Medical Research published online 6 February 2013
DOI: 10.1177/0300060513477582
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Research Note
Consolidation therapy is
necessary following
successful biofeedback
treatment for pubertal
chronic prostatitis patients:
a 3-year follow-up study
Journal of International Medical Research
0(0) 1–8
! The Author(s) 2013
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DOI: 10.1177/0300060513477582
imr.sagepub.com
Jun Wang, Lin Qi, Xiang Yang Zhang,
Yuan Qing Dai and Yuan Li
Abstract
Objective: To assess long-term effects of biofeedback training on pubertal chronic
prostatitis (CP).
Methods: Pubertal CP patients received 12-week intensive biofeedback training and were divided
into two groups: group 1 received further monthly training 24 (26–36) months; group 2 received
further monthly training <24 (13–23) months. National Institutes of Health–CP Symptom Index
(NIH–CPSI) scores, maximum urinary flow rate (Qmax) and postvoid residual urine volume (PVR)
were recorded monthly.
Results: Total NIH–CPSI scores decreased significantly in group 1 (n ¼ 10; mean age SD
16.5 1.1 years) together with all subdomain scores (pain, urination, life impact). Total NIH–CPSI
scores increased significantly in group 2 (n ¼ 12; mean age SD 16.3 1.2 years) at 30 and 36
months, and were significantly different from group 1 at these time points. Urination and life-impact
scores increased significantly and Qmax decreased significantly in group 2 at 30 and 36 months.
PVR was unchanged in either group.
Conclusions: Twelve-week intensive biofeedback training requires lengthy consolidation sessions
to achieve long-term success. Further investigation should assess longer intervals between
consolidation sessions, for improving patient compliance and outcome.
Keywords
Biofeedback, chronic prostatitis, National Institutes of Health–Chronic Prostatitis Symptom Index
(NIH–CPSI), puberty, follow-up, urodynamics
Department of Urology, Xiang Ya Hospital, Central South
University, Changsha City, Hunan Province, China
Corresponding author:
Dr Yuan Li, Department of Urology, Xiang Ya Hospital,
Central South University, 87 Xiangya Road, Changsha City,
410008, Hunan province, China.
Email: liyuanwooods@126.com
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Date received: 27 July 2012; accepted: 9 December 2012
Introduction
The pathogenesis of chronic prostatitis/
chronic pelvic pain syndrome (CP/CPPS) is
unclear, making treatment difficult.1 The
cause of CP may be associated with pelvicfloor abnormalities,2 with the majority
of CP patients in one study having pathological tenderness of the striated pelvic-floor
muscles and poor or absent pelvic-floor
function.3 Pelvic-floor biofeedback training
has been applied to the treatment of CP,
whereby specific instruments are used to
teach patients how to contract and relax
pelvic muscles selectively, while keeping
other muscles relaxed.4,5
There are few reports regarding the treatment of pubertal patients with CP. The
authors of the present study published data
on 25 male adolescents with CP who underwent biofeedback training and obtained
satisfactory short-term results.6 The initial
study showed that the main type of CP
during puberty is the National Institutes of
Health (NIH) prostatitis classification category IIIB (chronic prostatitis/chronic
pelvic pain syndrome, noninflammatory),7
with voiding disorder as the dominating
symptom. The impact on health-related
quality of life and psychological effects are
substantial. Using the NIH–CP Symptom
Index (NIH–CPSI) scores,8 our earlier study
reported mean pain subscores of 4.0 among
pubertal CP patients prior to receiving biofeedback treatment.6 Pain subscores among
adults with CP are reported to be 11.0.9,10
It has been suggested that disease characteristics are different among patients with
CP during puberty. Pubertal males with CP
have pelvic-floor dysfunction and several
abnormal urodynamic features including
staccato voiding, detrusor–sphincter dyssynergia, decreased maximum urinary flow
rate (Qmax), and increased detrusor pressure
at maximum cystometric capacity and
maximum urethral closure pressure.6 The
short-term (12-week) effect of biofeedback
strategies for treating pubertal CP is satisfactory because of the significant difference
in NIH–CPSI scores and Qmax before and
after treatment.6 The long-term durability
of biofeedback therapy for pubertal CP
patients remains unknown, however.
Whether it is necessary to add follow-up
consolidation therapy for these patients
remains to be understood.
The present follow-up investigation
explored the long-term effects and optimal
treatment protocol for pubertal CP patients.
Patients and methods
Study Population
This follow-up study was conducted at the
Department of Urology, Xiang Ya Hospital,
Central South University, Changsha City,
Hunan Province, China, between March
2006 and March 2009. Consecutive pubertal
CP patients who had received 12-week intensive biofeedback training (as described in
Li et al.6) were enrolled. There were no other
specific inclusion or exclusion criteria for the
study. Ultrasound examinations were performed to exclude any possible urological
anatomical abnormalities. Following prostate massage, expressed prostatic secretions
and urine samples were cultured to determine the presence of bacterial infection.
Patients were categorized according to the
NIH–CPSI score criteria.7
Patients or their parents provided written
informed consent and the study was
approved by the Institutional Review
Board of Central South University.
Study Design and Assessments
Patients received follow-up consolidation
biofeedback training once per month for
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Wang, et al.
3
13–36 months. Biofeedback training was
administered via a system that allowed
simultaneous recording of urine flow,
abdominal pressure and anal electromyogram (EMG) (Urostym; Laborie, Montreal,
Canada). An anal electrode was used to
indicate changes in EMG and a balloon
catheter was placed in the rectum to measure
abdominal pressure. Patients were taught to
perceive relaxation and contraction of the
anal sphincter, and instructed to contract
while simultaneously maintaining stable
abdominal pressure. Once the patient understood this procedure they chose the optimal
position for relaxation of the pelvic-floor
muscles. They were then instructed to urinate when sitting with the thighs spread (to
relax the perineum), while leaning forward
slightly with a straight back. Each session
lasted 20–30 min. During these visits, NIH–
CPSI scores,8 maximum urinary flow rate
(Qmax, obtained using free uroflowmetry)11
and postvoid residual volume (PVR,
obtained using ultrasound) were measured
and recorded for each patient.
Patients were divided into two groups
depending on the duration of consolidation
sessions; the duration of consolidation sessions was based on each patient’s own
decision to comply. Group 1 received biofeedback training once a month for 24
months after the initial 12-week intensive
training, and group 2 received <24 months’
training. Patients in group 2 were still
required to attend the clinic for assessment
and data collection on a monthly basis for
up to 36 months, even after their follow-up
training was suspended. No antibiotic or
a-blocker treatments were used on any of
the patients in this study.
Statistical Analyses
Statistical analyses were carried out
using the SPSSÕ software package, version
11.0 (SPSS Inc., Chicago, IL, USA) for
WindowsÕ . Data were reported as
mean SD values or median values (interquartile range). Between-group comparisons of NIH–CPSI scores, Qmax and PVR
were performed using the Mann–Whitney
U-test or independent-samples t-test.
Kendall’s W-test was used to analyse
within-group changes in total and subdomain NIH–CPSI scores. One-way analysis
of variance was used for within-group comparisons of Qmax and PVR. A P-value <0.05
was considered to be statistically significant.
Results
A total of 22 patients were included in the
study: 10 patients (mean SD 16.5 1.1
years of age) were assigned to group 1 and
received monthly follow-up training for a
mean of 29 months (range 26–36 months)
following initial 12-week intensive biofeedback training; 12 patients (mean SD
16.3 1.2 years of age) were assigned to
group 2 and received follow-up training for
a mean of 18 months (range 13–23 months)
following initial 12-week intensive biofeedback training. Of the 22 patients, one was
categorized as NIH prostatitis classification
category IIIA (chronic prostatitis/chronic
pelvic pain syndrome, inflammatory) and
21 patients were categorized as NIH prostatitis classification category IIIB (chronic
prostatitis/chronic pelvic pain syndrome,
noninflammatory).
All 20 patients found to have staccato
voiding in the previous study6 were included
in the present analysis. Of the 20 patients
with staccato voiding, after initial 12-week
intensive biofeedback training, symptoms
completely disappeared in 17 patients and
partial improvement was observed in three
patients (two of whom were assigned to
group 1; one was assigned to group 2).
Staccato voiding of the two patients in
group 1 completely disappeared following
12 weeks’ consolidation therapy, with no
cases reappearing in this group. Staccato
voiding of the one case in group 2 also
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disappeared after 12 weeks’ consolidation
therapy, but this voiding pattern reappeared
6 months after biofeedback sessions were
suspended. In addition, a further two cases
of staccato voiding appeared in group 2 at
36 months, i.e. in the period after follow-up
biofeedback training had been suspended.
Follow-up training sessions in group 2
were suspended due to poor therapeutic
compliance. Some patients in group 1 also
did not receive follow-up training for the full
36 months, due to poor therapeutic
compliance.
Total NIH–CPSI scores in group 1
decreased gradually and significantly
(P < 0.001) throughout the follow-up training period (Table 1). Total NIH–CPSI
scores in group 2 increased significantly at
30 and 36 months (compared with baseline,
P < 0.001) and were significantly different
from group 1 at 30 and 36 months
(P 0.01). There was no significant change
in Qmax over time for group 1, whereas Qmax
decreased in group 2 at 30 and 36 months
compared with baseline, i.e. in the period
after biofeedback training had been suspended (P < 0.001). PVR did not
change significantly over time in either
group (Table 1).
Group 1 NIH–CPSI subdomain scores
(including pain, urination and life impact)
showed a significant gradual decrease
(P < 0.001) (Table 2). Group 2 urination
and life-impact scores significantly increased
at 30 and 36 months (compared with baseline; P < 0.001), although pain scores did not
change significantly (Table 2). NIH–CPSI
subdomain scores for pain, urination and
life impact were all significantly different in
groups 1 vs group 2 at 30 and 36 months
(P 0.01, all comparisons; Table 2).
Discussion
The term ‘biofeedback’ describes procedures
developed in the 1940s for training subjects
to alter physiological responses such as
brain activity, blood pressure, muscle tension, or heart rate.12 Urodynamic biofeedback was first reported for managing
voiding
dysfunction
in
children.13
Biofeedback training teaches participants
to improve their health and performance
using their own body signals, strengthening
awareness of the connections between mind
and body.14–16 Biofeedback training has
been shown to improve symptoms of CP in
pubertal patients, over the short term.6 The
long-term effects of various treatment
options for pubertal CP patients, including
biofeedback training, remain unclear,
however.
The present study showed that 12-week
intensive biofeedback training, followed by
successive consolidation treatment for
pubertal CP, was effective in most patients.
NIH–CPSI scores for those who received
follow-up biofeedback training for 24
months
gradually
and
significantly
decreased, with no significant changes in
Qmax and PVR, indicating that consolidation biofeedback treatment for pubertal
patients with CP was satisfactory. In
patients who received follow-up biofeedback training for < 24 months, NIH–CPSI
scores decreased up to 24 months but then
began to increase, mainly due to increasing
urination and life-impact subdomain scores.
Qmax in these patients decreased significantly
after treatment was suspended. Symptoms
of pubertal CP patients in the present study
deteriorated rapidly after biofeedback training was suspended for >6 months, even if
follow-up consolidation biofeedback treatment had been conducted for >18 months.
The exact mechanisms through which
biofeedback training improves the symptoms of patients with CP are complex.9 It is
unclear why 12 weeks’ intensive biofeedback
training, followed by successive consolidation therapy for >18 months, did not
resolve CP symptoms in the present study.
There are various theories regarding the
basic causes of CP. A six-domain clinical
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Wang, et al.
5
Table 1. National Institutes of Health–Chronic Prostatitis Symptom Index (NIH–CPSI) total scores,
maximum urinary flow rate (Qmax) and postvoid residual volume (PVR) data for pubertal chronic prostatitis
patients who received consolidation follow-up biofeedback training for 24 months (Group 1; mean age SD
16.5 1.1 years) or <24 months (Group 2; mean age SD 16.3 1.2 years), on completion of 12 weeks’
intensive biofeedback training
Parameter
NIH–CPSI score, months
0
6
12
18
24
30
36
Statistical significanceb
Qmax, ml/s, months
0
6
12
18
24
30
36
Statistical significancec
PVR, ml, months
0
6
12
18
24
30
36
Statistical significanced
Statistical
significancea
Group 1 n ¼ 10
Group 2 n ¼ 12
7.5 (3.7)
7.5 (4.7)
6.5 (3.2)
5.5 (3.0)
6.0 (3.2)
3.0 (2.5)
2.0 (1.2)
P < 0.001
9.0 (6.7)
8.5 (4.2)
6.0 (2.5)
5.0 (3.2)
5.5 (4.7)
13.5 (9.5)
15.0 (2)
P < 0.001c
NS
NS
NS
NS
NS
P ¼ 0.001
P < 0.001
13.7 1.9
12.6 1.5
13.1 1.1
13.7 1.2
13.9 1.1
13.8 1.0
14.0 1.2
NS
14.5 1.3
11.8 1.6
12.7 1.9
13.0 1.4
12.7 1.5
11.6 1.6
9.5 2.2
P < 0.001c
NS
NS
NS
NS
NS
P ¼ 0.002
P < 0.001
5.9 2.6
4.6 2.8
4.3 2.2
4.6 1.2
5.2 1.1
5.3 1.2
5.2 1.3
NS
5.6 2.8
4.7 3.7
4.3 2.2
4.7 1.5
5.4 1.3
5.4 1.7
5.2 1.3
NS
NS
NS
NS
NS
NS
NS
NS
Data presented as median (interquartile range) or mean SD.
a
Between-group analysis, Mann–Whitney U-test or independent samples t-test.
b
Within-group analysis, Kendall’s W-test.
c
Statistically significantly different versus baseline only at months 30 and 36 in Group 2.
d
Within-group analysis, one-way analysis of variance.
0 months, represents commencement of follow-up training on completion of intensive 12-week biofeedback training.
NS, no statistically significant between-group or within-group differences (P 0.05).
phenotype-based classification system (urinary, psychosocial, organ-specific, infection,
neurologic/systemic and tenderness) has
been proposed as a means of improving
the understanding and management of
chronic prostatitis/chronic pelvic pain
syndrome and interstitial cystitis/bladder
pain syndrome.17,18 The suggestion was
that successful management of CP will
result from interventions that are specific
to a patient’s needs.17,18 The psychological
effects and impact on health-related quality
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Table 2. National Institutes of Health–Chronic Prostatitis Symptom Index (NIH–CPSI) subdomain scores
for pubertal chronic prostatitis patients who received consolidation follow-up biofeedback training for 24
months (Group 1; mean age SD 16.5 1.1 years) or <24 months (Group 2; mean age SD 16.3 1.2
years), on completion of 12 weeks’ intensive biofeedback training
NIH–CPSI subdomain
Pain, months
0
6
12
18
24
30
36
Statistical significanceb
Urination, months
0
6
12
18
24
30
36
Statistical significanceb
Life impact, months
0
6
12
18
24
30
36
Statistical significanceb
Statistical
significancea
Group 1 n ¼ 10
Group 2 n ¼ 12
2.0 (2.0)
2.0 (1.2)
2.0 (1.0)
1.5 (2.0)
1.5 (1.0)
1.0 (0.5)
0.2 (1.0)
P < 0.001
3.0 (2.0)
2.0 (1.0)
1.5 (1.0)
1.0 (1.0)
1.0 (2.0)
2.0 (2.2)
2.0 (2.0)
NS
NS
NS
NS
NS
NS
P ¼ 0.01
P < 0.001
3.0 (1.2)
3.5 (2.0)
3.0 (2.0)
2.0 (1.0)
2.0 (1.5)
1.0 (1.0)
1.0 (0.2)
P < 0.001
3.0 (3.2)
3.0 (1.5)
2.5 (1.0)
3.0 (1.2)
2.0 (2.2)
5.0 (3.2)
7.0 (2.0)
P < 0.001c
NS
NS
NS
NS
NS
P < 0.001
P < 0.001
2.0 (2.2)
2.0 (2.1)
2.0 (0.5)
2.0 (1.0)
2.0 (1.1)
1.1 (1.0)
1.0 (0.0)
P < 0.001
3.1 (3.0)
3.0 (2.0)
2.0 (1.0)
1.5 (1.0)
1.5 (2.5)
5.0 (4.2)
6.0 (3.5)
P < 0.001
NS
NS
NS
NS
NS
P ¼ 0.01
P < 0.001
Data presented as median (interquartile range).
a
Between-group analysis, Mann–Whitney U-test.
b
Within-group analysis, Kendall’s W-test.
c
Statistically significantly different versus baseline only at months 30 and 36 in Group 2.
0 months, represents commencement of follow-up training on completion of intensive 12-week biofeedback training.
NS, no statistically significant between- or within-group differences (P 0.05).
of life were substantial in the present study
and in the previously published report on
CP during puberty.6 Patients may benefit
more from biofeedback training if they
could recognize the basic aetiology of CP
and understand the benefit of relaxation.
Treating one specific symptom (such as
urinary dysfunction or tenderness) may not
be sufficient. Consequently, a combination
of biofeedback training with other therapies
such as psychological treatment may offer
greater efficacy.
The dominating symptom of pubertal CP
patients is voiding disorder.6 Dysfunctional
voiding (including staccato and fractionated
voiding) has been considered to be an
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Wang, et al.
7
abnormal contraction of the voluntary
sphincter mechanism, which can be managed by biofeedback therapy.19–21 It was
assumed that children with dysfunctional
voiding in these two studies were different
from the pubertal CP patients included in
the present study who showed voiding disorder, where intensive biofeedback training
was not sufficient.
Patients who received follow-up biofeedback for <24 months showed gradually
decreasing Qmax scores and increasing pain
and life-impact scores, following suspension
of biofeedback training. One study reviewed
the charts of 77 children with dysfunctional
voiding, where follow-up biofeedback therapy sessions were scheduled at 4- to 8-week
intervals.22 Success, improvement and failure were achieved in 22 (28.6%), 29 (37.7%)
and 26 cases (33.7%) respectively. The study
reported that children who completed three
biofeedback sessions were more likely to
succeed in improving their staccato voiding
pattern. Compared with the present study,
far fewer sessions were used to treat children
with dysfunctional voiding, however, the
patients (mean age, 9 years) were younger
than those included in the present study.
Since biofeedback training once per month
was not tolerated by some patients in the
present study, a further investigation should
consider follow-up biofeedback training at
2- or 3-month intervals, but not at intervals
>6 months.
The present study was limited by the fact
that incidence of CP in puberty is relatively
low and there were not enough patients
recruited to create a control group with no
intervention. In addition, the follow-up data
were difficult to collect. The sample sizes for
each group were relatively low, although
adequate to meet the demands of statistical
design.
In conclusion, a successful outcome was
achieved in pubertal patients with CP following an initial 12-week period of intensive
biofeedback training. Nevertheless, a
subsequent relatively long duration of consolidation sessions is needed to maintain
these results. A modified follow-up training
schedule should be further investigated, to
assess whether longer intervals between
follow-up biofeedback training would be as
effective as monthly intervals and better
tolerated by patients, thereby improving
patient compliance and outcomes.
Declaration of Conflicting Interest
The Authors declare that there are no conflicts of
interest.
Funding
This research received no specific grant from any
funding agency in the public, commercial, or notfor-profit sectors.
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