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- Review -
Common approach to managing lower urinary tract symptoms and erectile dysfunction
Jennifer M. Taylor1, Rowena DeSouza1, Run Wang1, 2
1Division of Urology, University of Texas Medical School at Houston, Houston, TX 77030, USA
2Department of Urology, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
The present paper serves as a review of the associations between lower urinary tract symptoms (LUTS) and
erectile dysfunction (ED), with a focus on common and combined pathways for treatment. LUTS and ED are
common conditions seen in general urologic practice. Research has started to establish epidemiologic and
pathophysiologic links between the two conditions and a strong association confirmed across multiple studies. Men
seeking care for one condition should always be interviewed for complaints of the other condition. Proposed
common pathways include a-1 adrenergic receptor imbalance, Rho-kinase overactivity, endothelial cell dysfunction and
atherosclerosis-induced ischemia. Medical therapy has replaced surgery as the first-line treatment for LUTS in most
patients, with the incorporation of a-adrenergic receptor antagonists
(α-ARAs) and 5-a-reductase inhibitors
(5-ARIs) into everyday practice. Treatment with α-ARAs contributes to some improvement in ED, whereas use of
5-ARIs results in worsened sexual function in some patients. Phosphodiesterase-5 (PDE-5) inhibitors have
revolutionized the treatment of ED with a simple oral regimen, and new insights demonstrate a benefit of combined use of
PDE-5 inhibitors and α-ARAs. The mechanisms of action of these medications support these observed benefits, and
they are being studied in the basic science and clinical settings. In addition, novel mechanisms for therapy have been
proposed based on clinical and research observations. The minimally invasive and surgical treatments for LUTS are
known to have adverse effects on ejaculatory function, while their effects on erectile function are still debated. Much
remains to be investigated, but it is clear that the associations between LUTS and ED lay the foundation for future
therapies and possible preventative strategies.
(Asian J Androl 2008 Jan; 10: 45_53)
Keywords: erectile dysfunction; lower urinary tract symptoms; benign prostatic hyperplasia; medical therapy
Correspondence to: Run Wang, MD, FACS, Departments of Urology, University of Texas Medical School at Houston and University of
Texas MD Anderson Cancer Center, 6431 Fannin Street, MSB 6.018, Houston, TX 77030, USA.
Tel: +1-713-500-7337 Fax: +1-713-500-0546
In the practice of urology, lower urinary tract symptoms (LUTS) and erectile dysfunction (ED) are
conditions encountered on a daily basis. Both LUTS and ED demonstrate increasing prevalence with advancing age, and a great deal
of epidemiologic and clinical research has been done to study the two processes. The two conditions are strongly linked,
and investigation continues into the etiology of each condition, with particular attention being paid to common pathways.
There are several avenues of treatment for each condition, and research is ongoing into the overlap and interactions of
The symptom spectrum of LUTS in men is the manifestation of benign prostatic hyperplasia (BPH) and bladder
outlet dysfunction as obstructive and irritative voiding symptoms, which can include frequency, urgency, nocturia,
decreased force of stream, intermittent stream and
incomplete bladder emptying. BPH is a histological
diagnosis indicating cellular proliferation of the stromal and
epithelial elements of the prostate gland. This
histological diagnosis is made at autopsy in 8% of men aged
31_40 years, 50% of men aged 51_60 years, 70% of those
aged 61_70 years, and 90% in those aged 81_90 years
. These data compiled from 10 studies of more than
1 000 prostates clearly illustrate the increasing
prevalence of BPH with age. BPH can lead to complaints of
LUTS; however, the incidence of pathologic BPH is much
higher than the incidence of symptoms attributable to
BPH. Clinically, the International Prostate Symptom
Score (IPSS) is a widely-used, validated instrument for
evaluating symptoms of LUTS and tracking response to
treatments. The prevalence of symptomatic BPH (IPSS
score > 8) is estimated to be between 18% in men 40_49
years old to 56% in men 70_79 years old, based on IPSS
responses from over 4 000 men in Asia . Similarly
reported prevalence in other regions of the world ranges
from 8% to 36% in men 50_59 years old and from 27%
to 37% in men 70_79 years old . Clearly, not all
patients with BPH develop LUTS, and not all patients
presenting with LUTS have objective evidence of BPH. The
symptoms of LUTS can also be attributed to the smooth
muscle tone of the prostatic capsule and bladder neck.
This etiology has been confirmed through the efficacy
of α-adrenergic receptor antagonists (α-ARAs) in the
treatment of LUTS; by their mechanism of smooth muscle relaxation, they facilitate bladder emptying.
Sexual dysfunction includes ED, ejaculatory
dysfunction and hypoactive sexual desire. ED is defined as the
inability to achieve or maintain an erection sufficient for
satisfactory sexual performance . The prevalence of
ED in men ages 40_70 years with comorbidities is
estimated at 9.7% overall, with rates of 39% in men with
heart disease, 29% in men with diabetes, and 15% in
those with hypertension . When stratified by age,
prevalence of ED increased from 40% with mild ED and
5% with severe ED at age 40 years, to 70% and 15%,
respectively, at age 70 years . In clinical evaluation,
the International Index of Erectile Function (IIEF) and
Danish Prostate Symptom Score sex questionnaire
(DAN-PSSsex) have been validated as tools for assessing
erectile ejaculatory function.
Numerous studies have established a link between
LUTS and ED. Epidemiologic data cannot establish
causality between the two conditions, but they can and do
demonstrate reproducible associations between the two
conditions. Sexual dysfunction is more prevalent in men
with LUTS. The UrEpik study  reported questionnaire responses of 4 800 men in four countries and found
that men with self-reported LUTS are more likely to
report ED after adjustment for age. Other comorbidities
are also associated with ED, including diabetes,
hypertension and tobacco use. The Cologne Male Study 
surveyed almost 5 000 men aged 30_80 years, with an
overall prevalence of ED of 19%. This prevalence, when
stratified for LUTS, was 72% in men with LUTS and 37% in men without LUTS; this statistically significant
difference persisted independent of age. Further
analysis of this dataset demonstrated LUTS to be an
independent risk factor for ED . The Multinational Study of
Aging Male (MSAM)-7 study , which evaluated
questionnaire responses of 12 815 men, confirmed the link
by demonstrating that ED is associated with the severity
of LUTS; the analysis found that LUTS and age are
stronger risk factors for ED than other comorbid conditions
such as diabetes, hypertension or hyperlipidemia.
It is important to be aware of the possible positive
and negative effects of medication for one condition on
the symptoms of the other condition. There is evidence
for increased and decreased ED with medical and
surgical therapies for LUTS. In addition to common risk
factors, it is thought that the psychological impact of
LUTS on quality of life might alter a patient's erectile
function . The pathophysiologic effects of LUTS
on ED might also be an important factor, and research is
ongoing to examine and clarify this complex relationship.
Given the evidence and ongoing research, a clinician,
when seeing a patient for one of the two conditions,
should always include questions regarding the other
3 Common pathophysiology
Research has identified several possible pathways
through which LUTS and ED develop. The predominant theories for association involve changes in
α-adrenergic receptor regulation, increased Rho-kinase
activity, endothelial dysfunction and atherosclerotic
The various subtypes of α-1 adrenergic receptors
have been studied and identified in the bladder, prostate
and penile tissue. Table 1 details the subtypes and their
In the corpus cavernosum, adrenergic receptors mediate smooth muscle and vascular tone; decreased
adrenergic input mediates smooth muscle relaxation and
decreases vascular tone to allow erection while
adrenergic receptor activation induces smooth muscle
contraction and increases vascular tone to cause detumescence
. This knowledge raises the possibility of aberrant
smooth muscle contraction as a common etiology of both
LUTS and ED. With age, glandular proliferation occurs
and the density of α-adrenoceptors increases.
Alpha-1A receptors concentrated in prostate and
bladder neck are involved in voiding problems and
α-1D receptors found in hypertrophied detrusor muscle are
involved in storage problems . α-1A and α-1D
receptors have been identified as the predominant
a-1-adrenoceptor subtypes in penile corpus cavernosum .
Another autonomic mediated pathway is that of Rho
and Rho-associated kinase. Increased Rho-kinase
activity leads to increased smooth muscle contraction, which
in turn contributes to impaired erectile function and
changes in bladder outlet tone . Jin
et al.  demonstrated in a rat model that increased
RhoA/Rho-kinase signaling coincides with the development of ED with
aging. Inhibition of Rho-kinase in the rat model has been
shown to decrease prostatic smooth muscle cell
proliferation and to decrease adrenergic contractions .
Administration of an oral Rho-kinase inhibitor, fasudil,
prevented atherosclerosis, endothelial injury and
associated ED in rats; the control set of rats was found to
have elevated cavernosal Rho-kinase activity and
decreased eNOS expression with ED .
Endothelial dysfunction is central to the development
of both conditions. Nitric oxide (NO) induces
vasodilation, and it is the basis for using phosphodiesterase-5
(PDE-5) inhibitors in the treatment of ED. NO has also
been identified in prostate and bladder tissue, and some
nitrenergic receptors are found in human hyperplastic
prostate tissue . NO synthase gene expression is
reduced with aging in rat prostate tissue and might be a
factor for increased smooth muscle tone associated with
LUTS . PDE receptors have been characterized in
prostatic tissue, but more research is needed regarding
their impact on prostatic smooth muscle tone .
Atherosclerosis causes chronic ischemia to organs,
including the bladder, prostate and penis, and many
factors, such as diabetes, hypertension, hyperlipidemia
and smoking, are known to contribute to or accelerate
its development. The metabolic syndrome, which includes cardiovascular and diabetic risk factors, can cause
autonomic hyperactivity, and the sequelae of chronic
ischemia might involve many of the above pathways. ED
is considered a risk marker for the metabolic syndrome
and its associated comorbidities .
4 Impact of medications used to treat LUTS on ED
4.1 α-adrenergic receptor antagonists (α-ARAs)
Considered first-line therapy for symptoms
secondary to BPH, α-ARAs have changed the management of
LUTS. The four currently available formulations are
alfuzosin, tamsulosin, doxazosin and terazosin. The
American Urological Association (AUA) Guideline
Committee performed a meta-analysis of over 5 900 men
treated for 3 to 9 months and over 6 500 men treated for
10 to 16 months . The analysis demonstrated a mean
IPSS improvement of 2_2.5 points and minimal
differences in symptom improvement between the four agents
However, differences were found in side effect profiles, as noted in Tables 2 and 3. Overall, tamsulosin
and alfuzosin were associated with fewer
vascular-related adverse effects. They are considered uroselective
in nature: alfuzosin is preferentially distributed in
prostatic tissues , and tamsulosin has shown greater
affinity for receptor subtypes 1A and 1D [27, 28].
None of the four agents demonstrated a deleterious
effect on erectile function when compared to placebo.
In contrast, several basic science and clinical studies have
demonstrated a beneficial effect on sexual function while
on therapy with α-ARAs for LUTS.
Research involving rabbit cavernosal smooth muscle
has demonstrated relaxation of the smooth muscle by
alfuzosin, very similar to the effects of phentolamine and
sildenafil . This relaxation was instigated by an
α-adrenergic blockade, and suggests a beneficial influence
of alfuzosin on erectile function.
Nearly 5 000 men in the community setting in
multiple countries were followed for 6 months on alfuzosin
, and symptoms and side effects were assessed
using self-administered validated questionnaires. The
average changes in self-reported symptoms reflected
improvement in both LUTS and ED. IPSS scores improved an
average of 6 points, while significant improvement from
2.5 to 2.0 in mean score (both, P < 0.001) was seen on
the erection rigidity domain of the DAN-PSSsex. Approximately 5% of patients withdrew secondary to
postural dizziness, and less than 1% withdrew from the study
as a result of diminishing erectile function.
Rosen et al.  performed a placebo-controlled study
on the effect of alfuzosin on sexual function in 372 men
with LUTS on alfuzosin. After 1 month of treatment,
responses on the erection rigidity question of the
DAN-PSSsex revealed an improvement in erectile function in
men receiving alfuzosin versus a decline in function in
men receiving a placebo (P = 0.02), with dizziness being
the main side effect reported in 5% of men on alfuzosin.
A pooled analysis of three randomized,
placebo-controlled studies involving alfuzosin evaluated data on 473
men who took alfuzosin and 483 men who used a placebo
for 12 weeks ; mean improvement in IPSS was 6.0
points with alfuzosin versus 4.2 points with a placebo
(P < 0.005).
A multicenter study by De Rose
et al.  followed patients with BPH on doxazosin for 3 months. The
authors found a statistically significant improvement in IIEF
score in 35% of the men with ED at baseline; within this
group of men, 66.5% of those with moderate to severe
ED at baseline (IIEF score 6_16) reported a significant
increase in IIEF score, reflecting a more profound
improvement in men with worse erectile function at baseline.
Another multicenter, randomized study comparing doxazosin in standard versus extended-release dosing
followed 680 men for 13 weeks and noted improvements
in sexual function based on IIEF responses in those
patients with sexual dysfunction at baseline .
Tamsulosin has been found to have the highest
incidence of ejaculatory dysfunction, which is thought to be
related to its receptor selectivity. Phase III testing of
tamsulosin demonstrates a dose-dependent rate of
ejaculatory dysfunction, with 8% incidence in men using
0.4 mg and 18% of men taking 0.8 mg versus 0.2% in
the placebo arms . Another randomized
placebo-controlled, crossover study showed that 0.8 mg of
tamsulosin decreased mean ejaculate volume in almost
90% of men with 35% having no antegrade ejaculation,
while no change in ejaculatory volume was observed in
the men taking alfuzosin .
A retrospective study reviewed questionnaire responses of 7 974 men using tamsulosin compared with
men taking other medications for BPH symptoms and men on no medication . Linear regression of SHIM
(abridged IIEF) scores on AUA symptom scores revealed
that erectile function was best preserved in men taking
tamsulosin, with the most benefit observed in men with
more severe LUTS.
A new α-1A receptor-selective antagonist for
treatment of LUTS, silodosin, is currently under investigation.
A phase III placebo-controlled comparison of silodosin
and tamsulosin (0.2 mg daily) demonstrated comparable
reductions in IPSS . It was noted to have a higher
incidence of ejaculatory dysfunction, and further
investigations for this indication are continuing with this agent.
4.2 5-α-reductase inhibitors (5-ARIs)
There are two 5-ARIs currently on the market: finasteride (Merck & Co., Whitehouse Station, NJ, USA)
and dutasteride (GlaxoSmithKline, Beinheim, France).
These two agents work through inhibition of
5-alpha reductase, which converts testosterone to
5-dihydroxytestosterone (DHT). DHT is the primary androgen
responsible for hyperplastic growth of the prostate, and
5-ARIs are used in men with very enlarged glands. The
type 2 enzyme is specific to prostate tissues, whereas
the type 1 enzyme is expressed in most tissues. Finasteride
is a selective inhibitor of the type 2 enzyme, while
dutasteride inhibits both type 1 and type 2 enzymes. Both
have been shown to have equivalent efficacy in treating
The use of both agents is associated with adverse
effects on sexual function. The PROscar Safety plus
Efficacy Canadian Two year Study (PROSPECT) study evaluated the use of finasteride versus placebo over
2 years and reported a 16% incidence of ED and 8%
incidence of ejaculatory dysfunction among the finasteride-treated patients versus 6% and 2%,
respectively, in the placebo arm . In a
non-placebo-controlled study comparing use of finasteride versus
dutasteride in 1 630 men over 48 months, the rates of
ED were comparable, at 8% and 7%, respectively .
In three placebo-controlled 2 year trials evaluating
dutasteride treatment in a total of over 4 300 men,
worsening sexual function, including ED, decreased libido and
ejaculatory dysfunction, was observed within 0_6 months
of treatment compared to the placebo; however, as
treatment continued to a total of 24 months, the rates of these
adverse effects were comparable to placebo rates with
no statistically significant difference . Similarly, the
use of finasteride versus a placebo for 4 years in over
3 000 men was studied in the Proscar Long-Term
Efficacy and Safety Study (PLESS); 15% of patients taking
finasteride versus 7% of those taking a placebo
developed sexual dysfunction during the first year .
However, the rate of self-reported sexual adverse events
from years 2 to 4 leveled off to 7% in both the finasteride
and placebo groups.
Mondaini et al.  examined the sexual side effects
in 107 men taking finasteride, comparing those who were
informed and those who were not informed prior to
treatment of the possible sexual side effects; interestingly,
the researchers found that the men informed of the
potential side effects reported a significantly higher rate of
sexual dysfunction at 6 and 12 months .
Despite differences in enzyme type specificity, with
dutasteride demonstrating greater reduction in serum
levels of DHT, no significant difference in efficacy has
been recorded. A review of trials involving both finasteride and dutasteride found similar effects on
reduction in prostate volume, flow rate, symptom
improvement, and progression .
Notably, 5-ARIs have proven to be effective in
reducing the risk of acute urinary retention and
progression to surgery, as demonstrated in the PLESS trial, with
review of the data at 4 and 6 years [43, 44]. A
retrospective review of the use of α-ARAs versus 5-ARIs
among 4 500 men demonstrated significantly greater rates
of progression, as measured by documentation of
urinary retention or BPH-related surgery, with α-ARAs at
all intervals from 6 to 24 months following initiation of
treatment . Over 24 months, surgery or
documentation of retention was recorded for 18.2% of men taking
α-ARAs vs. 10.7% of men taking 5-ARIs
(P < 0.001). This is a significant finding unique to 5-ARIs, which
warrants additional confirmation in clinical trials.
4.3 Combination therapy
Kaplan et al.  compared the effects of doxazosin
alone, finasteride alone, combination therapy, and a
placebo in 3 047 men over 4.5 years, and found a benefit in
treatment with combination therapy of finasteride and
doxazosin, specifically in men with a baseline prostate
volume of greater than 25 g . This study did not
report the effect of therapy on sexual function.
A retrospective review over 6_8 years in 192 men
treated with alpha-blockers alone and 149 men treated
with combination therapy of an α-ARA and 5-ARI 
found statistically significant differences in the outcomes
of episodes of acute urinary retention (17.7% with
α-ARA alone, 12.1% with combination,
P < 0.05) and surgical intervention (10.9% with
a-ARA alone, 6% with combination,
P < 0.05). The effects of therapy on sexual
function were also not reported.
However, McConnell et al.  found a cumulative
risk of sexual side effects with combination therapy when
compared to monotherapy or placebo. The rates of ED
in the finasteride-alone (4.53 per 100 person-years) and
combination therapy (5.11) groups were significantly
higher than the rate in the doxazosin-alone group (3.56),
which was not significantly higher than in the placebo
group (3.32). The rates of decreased libido and
ejaculatory dysfunction were also increased.
Combination therapy might reduce symptoms of LUTS, but clinicians should be aware of the potential
additive effect on sexual function.
5 Impact of medications used to treat ED on LUTS:
This class of medication for the treatment of ED act
by potentiation of the action of NO on penile smooth
muscle cells. NO activates guanylate cyclase, the
enzyme that produces cyclic GMP, which mediates
hyperpolarization and subsequent relaxation of smooth muscle
cells. PDE-5 inhibitors block the degradative action of
phosphodiesterases on cyclic GMP and thereby prolong
the relaxation of smooth muscle cells causing an erection.
An investigation of PDE-5 receptor expression and
PDE-5 inhibitor activity in rat bladder and prostate tissue
noted that PDE-5 signaling was involved in bladder
smooth muscle tone and prostatic stromal proliferation
. PDE-5 inhibitor activity led to reduced
contractions in the tissues and decreased proliferation of
prostatic stromal cells, and the lessened irritative symptoms
in an outlet obstruction model. This study found vardenafil to be more potent than either sildenafil or tadalafil
and suggested a possible role for use of PDE-5 inhibitors
in the treatment of irritative LUTS. Vardenafil was
administered as 10 mg twice a day for 8 weeks in a
randomized, double-blind, placebo-controlled study in 215 men
with LUTS for at least 6 months . The results
presented at the 2007 AUA meeting showed that Vardenafil
significantly improved the mean IPSS from 16.8 to 11.0
compared to placedo with a change from 16.8 to 13.2
(P = 0.0013).
A pilot study evaluated IPSS and IIEF questionnaire
responses among 112 men treated with sildenafil on an
as-needed basis over 3 months . The results
demonstrated improvement in the IPSS scores with sildenafil treatment and noted that men with lower IPSS
scores at baseline responded better to treatment with
sildenafil. Currently, placebo-controlled studies with
sildenafil and tadalafil are underway to further study their
effects in men with LUTS .
One such study, with a double-blind placebo-controlled design, examined the effect of 12 weeks of daily
sildenafil on ED and LUTS, finding that the men
receiving sildenafil had significant improvements in erectile
function (9.17 vs. 1.86 point increase on IIEF erectile
function domain) and LUTS (6.32 vs. 1.93 point decrease in
IPSS score) . Daily tadalafil administration was also
studied in 281 men in a placebo-controlled setting and
found to be beneficial for LUTS, with significant
improvements in self-reported IPSS scores ; following
a 4-week placebo run-in period and 12 weeks of treatment,
the mean IPSS decreased by 7.1 points in men taking
tadalafil versus 4.5 points in men taking a placebo.
This preliminary evidence opens avenues for further
investigation into the benefits of PDE-5 inhibitors on
LUTS. A new PDE-5 inhibitor, udenafil, is approved for
use in South Korea and the UK. It is currently under
further investigation in phase II and phase III trials in the
USA ; no data have been published as to its effect on
LUTS, but will be worth following.
6 Effect of combined PDE-5 inhibitors and
α-ARAs on ED and LUTS
Researchers are investigating the effects α-ARAs
might have in the treatment of ED and the possible
influence that PDE-5 inhibitors might have on LUTS .
The presence of α-adrenoceptors types 1 and 2 in
penile tissue has been established, and it has been noted
that norepinephrine acting on these receptors caused
contraction of trabecular smooth muscle. a-adrenoceptor
antagonists facilitate penile erection and may result in
priapism in rare circumstances . Several α-ARAs
are available and have been used in the treatment of ED,
including phentolamine (α-1, α-2) as an injectable agent,
prazosin (α-1) as an oral or intraurethral agent, and
yohimbine (α-2) as an oral agent .
Researchers have examined the relaxant effects of
alfuzosin, phentolamine and sildenafil on corpus cavernosal tissue from rabbits and demonstrated
α1-adrenoceptor responsiveness in the tissues, with
relaxation seen with alfuzosin and phentolamine ;
sildenafil's ability to relax the tissues involves
Kaplan et al.  demonstrated that oral doxazosin
potentiated the erectile effect of alprostadil injected
intracavernosally . The Treatment of Mild
Hypertension Study (TOMHS) documented that patients
receiving doxazosin reported a lower incidence of ED .
Another trial, which randomized 28 men with ED who
had failed sildenafil monotherapy to treatment with
either sildenafil plus doxazosin or sildenafil plus a placebo,
found a statistically significant improvement in the IIEF
score in 78% of the men receiving combination therapy
vs. 7% of the men receiving sildenafil alone
(P = 0.0016) . Similarly, a retrospective study that looked at the
effect of adding oral alfuzosin to tadalafil, in men who
had previously failed use of tadalafil, found improved
erectile function in 71% of those treated .
A recent study randomized 62 men to alfuzosin 10 mg
daily, sildenafil 25 mg daily, or a combination of both
agents daily for 12 weeks . Based on IPSS and IIEF
responses, the researchers found greatest improvement
in LUTS and ED with the combination therapy (24.1%
change in IPSS and 58.6% change in IIEF with combination,
P = 0.002). These pilot studies provide a
foundation on which further investigation may be based.
Some degree of caution is advised with using PDE-5
inhibitors in conjunction with α-ARA. Several
placebo-controlled studies have examined the hemodynamic
effects of simultaneous administration. One trial found
that, when compared to those given doxazosin plus placebo, 89% of men given doxazosin plus tadalafil
exhibited significantly greater reductions in standing and
supine blood pressures . The same article reported
on a trial of the simultaneous administration of tamsulosin
and tadalafil and found that the changes in blood
pressure were similar to those with a placebo. Another study,
using tadalafil and alfuzosin versus a placebo
demonstrated no significant hemodynamic interaction between
tadalafil and alfuzosin . In men who have been on
long-term therapy with α-ARAs, the effect of PDE-5
inhibitors on blood pressure might be less significant .
7 Impact of surgery for BPH on erectile function
Surgical therapy for LUTS is indicated in men for
whom medical therapy has failed. The specific technique
used depends on the urologist's judgment of the patient's
clinical presentation and consideration of his
comorbidities. Surgical approaches range from minimally invasive
ablation with cautery procedures to open extirpation of
the entire gland.
The risk of ED after transurethral resection of the
prostate (TURP) is approximately 2%_10%, according
to the AUA Guideline's analysis of 15 trials. Notably, the
VA Cooperative Study, which randomized 556 men to TURP or watchful waiting and followed them for 3 years,
found that the rate of ED among men following TURP
was slightly lower than that among men managed with
watchful waiting ; the rate of worsening ED over
the course of the study was 19% in the surgery group
and 21% in the watchful waiting group. A randomized
comparison of TURP with holmium laser enucleating of
the prostate (HoLEP) in 120 patients with a mean age of
approximately 65 years found similar rates of
preexisting ED in both groups. Following surgery, the patients'
IIEF responses reflected new ejaculatory dysfunction in
over 60% of the patients in both groups and marginal
improvement in erectile function in both groups .
After 24 months, mean IIEF scores improved from 21.4
and 22.3 to 23.8 and 24.1, and the prevalence of ED in
the two groups decreased from 53.3% and 51.6% to 51.8%
and 48.3 %, respectively. Another randomized
comparison of TURP with HoLEP over 1 year in 200 patients
with mean age of approximately 68 years found the rates
of diminished erectile function to be similar, 10.5% after
TURP and 11.2% after HoLEP, and found improved
erectile function in 1 TURP patient and 3 HoLEP patients .
Alternative transurethral procedures exist, including
transurethral needle ablation (TUNA) and transurethral
microwave thermotherapy (TUMT). According to the AUA Guideline , the risk of ED after TUMT is no
worse when compared to a sham procedure and the risk
after TUMT or TUNA is less than the risk of ED
associated with TURP.
The number of TURPs performed for BPH-related disease in the SA has decreased from 250 000 in the late
1980s to 88 000 in the year 2000 ; this change is
largely due to the use of effective medical therapies for
symptomatic relief. This method still remains a valuable
option, particularly with large-volume glands. Among
these interventional therapies, open surgery is associated
with a high incidence of sexual dysfunction, cited as 10%
for ED and 65% for ejaculatory dysfunction .
Many theories on the pathophysiology of these two
conditions have been proposed and remain to be investigated. Testing of these theories might lead to novel
and integrated treatments. For now, the treatments
available are proving to be beneficial in ways not previously
known or studied. As research continues, men with
LUTS, ED or the coexistence of both will gain greater
benefit. This benefit might one day be extended to men
who have yet to suffer from LUTS or ED; through
better understanding of the mechanisms of how they
develop, prevention of both conditions simultaneously
might be possible.
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