Jump to: Page Content, Site Navigation, Site Search,
You are seeing this message because your web browser does not support basic web standards. Find out more about why this message is appearing and what you can do to make your experience on this site better.
BMJ 2006;333:535-539 (9 September), doi:10.1136/bmj.38946.616551.BE1
Anand K Patel, research registrar1, Christopher R Chapple, professor of urology and consultant urological surgeon1
1 Urology Research, J Floor, Royal Hallamshire Hospital, Sheffield S10 2JF
Correspondence to: CR Chapple c.r.chapple{at}sheffield.ac.uk
This article provides information on how to treat patients with lower urinary tract symptoms that are suggestive of bladder outflow obstruction, secondary to benign prostatic hyperplasia
The treatment of lower urinary tract symptoms that are suggestive of bladder outflow obstruction, secondary to benign prostatic hyperplasia, should aim to relieve symptoms and improve quality of life, as well as attempt to prevent progression of clinical disease and the development of complications. These benefits need to be balanced against potential side effects of treatment.
Patients with mild symptoms that have little impact on quality of life and who have no evidence of complications can be managed conservatively. They should be advised to reduce fluid intake and avoid caffeinated drinks and alcohol if appropriate. This requires the use of frequency and voiding charts.
It may be helpful to review the drugs they are taking, such as diuretics, and any impairment of mental state, dexterity, or mobility should be optimised to limit the impact on quality of life.1Patients selected for watchful waiting should be encouraged to seek medical advice if their symptoms deteriorate, so appropriate treatment can be initiated promptly.
Options if medical treatment is needed are:
Antagonists
Reductase inhibitors
Antagonists
Contraction of the prostatic smooth muscle occurs after activation of the
1 adrenoceptors. Inhibition of these receptors relaxes the muscle in the bladder out-flow tract; this decreases urinary outflow resistance and helps improve the symptoms.
Antagonists are the first line treatment for benign prostatic hyperplasia.
|
Benefits
Antagonists act rapidly (usually within 48 hours), and improvement of symptoms is immediately noticeable to the patient. About 70% of men will respond to this treatment, and non-responders can be identified rapidly and other treatments instigated.
Evidence
Many randomised controlled trials have been performed, and recent systematic reviews have confirmed that all
antagonists have a similar efficacy and that newer longer acting drugs are no more effective than older ones.2 These drugs tend to improve symptom scores by 30-40% and improve the maximum flow rate by 15-30%.3 Unlike 5
reductase inhibitors, they do not affect prostate volume and therefore do not alter disease progression.
Side effects
Although all
antagonists have similar efficacies, their side effects differ because they have different actions on
receptors in other organ systems, particularly the cardiovascular, central nervous, and genitourinary systems (box).
|
Abnormal ejaculation is a recognised side effect of treatment with an
antagonist.4 No
antagonist has been shown definitely to have a better profile for this side effect, although a higher incidence of abnormal ejaculation has been reported for tamsulosin.
Elderly patients are less likely to discontinue treatment because of ejaculatory dysfunction than cardiovascular side effects. The cardiovascular side effects should determine the choice of
antagonist in older patients but not in younger men.
Alfuzosin
Open label studies with alfuzosin have shown that patients with pre-existing cardiovascular disease or those taking other drugs are at increased risk of developing cardiovascular side effects with this drug. This is also the case for patients over 74 years.5
However, prolonged release formulations have fewer age related side effects and are associated with only a slightly increased risk of cardiovascular side effects in patients with pre-existing hypertension.6 The side effects therefore depend on the formulation, and this should be considered carefully when choosing a preparation.
Doxazosin
Four studies have shown an increase in cardiovascular side effects when this drug is used in patients with known or treated hypertension. Data were consistent across all four studies but were not statistically significant, probably because of the low number of patients in the hypertensive subgroups.5
Terazosin
Blood pressure was lowered more frequently with this drug than with placebo, but cardiovascular side effects were not significantly different in the hypertensive and non-hypertensive subgroups.7
Tamsulosin
Trials have confirmed that tamsulosin is well tolerated and that side effects are not significantly different from placebo in elderly patients and patients with hypertension.8
Three randomised controlled trials have studied the effect of concurrent treatment with tamsulosin and antihypertensive drugs (nifedipine, enalapril, and atenolol). They found no alteration in the pharmaco-dynamic response and no need to adjust the dose of the antihypertensive drugs.9 Blood pressure is lowered further when a phosphodiesterase type 5 inhibitor (sildenafil, tadalafil, and vardenafil) is added to most
antagonists, although this effect is minimal with tamsulosin.10
Recently a new controlled release delivery system for tamsulosinthe oral controlled absorption system (Flomaxtra XL) has been developed to achieve continuous and consistent absorption of tamsulosin throughout the gastrointestinal system. This new preparation maintains consistent 24 hour plasma concentrations of the drug.11 However, the efficacy is similar to existing preparations.
Doses
Recommendations
Antagonists are suitable for patients with moderate to severe lower urinary tract symptoms and a low or intermediate risk of progression of disease. Based on systematic reviews, tamsulosin and once daily preparations of extended release alfuzosin have the lowest risk of cardiovascular adverse events and are suitable as first line agents, especially in high risk and elderly patients.12 The other
antagonists are appropriate for younger patients or those unlikely to have cardiovascular side effects.
Floppy iris syndrome, which may cause technical problems during cataract surgery, has recently been reported as a side effect of
antagonists. This syndrome is seen most often with tamsulosin, and ophthalmologists undertaking cataract surgery need to identify patients who are taking an
antagonist.13
Reductase inhibitors
Testosterone is converted to dihydrotestosterone by the enzyme 5
reductase within prostate cells. Dihydrotestosterone acts on prostatic tissue to inducebenign prostatic hyperplasia. 5
Reductase inhibitors decrease the production of dihydrotestosterone, thereby arresting prostatic hyperplasia.
|
Two 5
reductase inhibitors are licensed in the United Kingdom, finasteride and dutasteride (table 1).
|
Benefits
5
Reductase inhibitors are thought to decrease the progression of disease and the development of acute urinary retention. They are especially beneficial for patients with risk factors for progression of disease (table 2).15
|
The reduction in risk is a consequence of the decrease in prostate volume with the use of 5
reductase inhibitors. However, shrinkage is slow and symptoms often do not improve in the first six months of treatment.
Side effects
Side effects are:
Evidence
Finasteride
A systematic review of 19 randomised placebo controlled trials showed that symptom scores and flow rates consistently improved and prostate volume decreased by 25% in patients on finasteride.16 However, about a third of men stopped taking finasteride over two years. Only 6% of these men stopped because of lack of benefit and 12% stopped because of side effects, and the number of men who stopped taking finasteride was not significantly different from those who stopped taking placebo.
Dutasteride
Two multicentre randomised placebo controlled trials lasting two years with open label extension for a further two years have been pooled.17 These showed improved symptom scores, a 26% decrease in prostatic volume, and improved urinary flow rates with dutasteride. They also showed a 57% reduction in relative risk of acute urinary retention and a 48% reduction in relative risk of the need for prostatic surgery.
However, a large head to head randomised multicentre comparison trial between finasteride and dutasteride found no significant difference between these drugs with respect to their safety profiles or changes in prostate volume, symptom score, or peak flow rate.14 18 Thus little difference exists between the two drugs, and a dual action 5
reductase inhibitor does not seem to be of additional benefit in the management of benign prostatic hyperplasia.
Doses
Cautions
Both dutasteride and finasteride decrease serum concentrations of prostate specific antigen by about a half, and reference values need to be adjusted if a patient is suspected of having or is being followed up for prostate cancer.
Recommendations
5
Reductase inhibitors are a suitable option in patients with moderate or severe lower urinary tract symptoms with an obviously enlarged prostate or prostate specific antigen concentration greater than 1.4 µg/litre.19 Both currently available agents have similar efficacies and profiles of adverse events. It should be stressed to the patient that there may be no apparent improvement in symptoms for six months and that treatment will need to continue long term.
The well publicised medical therapy of prostatic symptoms (MTOPS) multicentre randomised controlled trial looked at the long term progress (mean 4.5 years) of patients randomised to either placebo, finasteride, doxazosin, or both (combination therapy).20
The trial showed that finasteride and doxazosin had a similar ability to prevent progression of disease (34-39% compared with placebo), but the combination of both drugs was more effective (66% compared with placebo). However, the end points used to measure progression of disease were controversial.
The risks of progression to acute urinary retention or the necessity for surgery were also significantly reduced by both finasteride and combination therapy, but not by doxazosin alone. However cumulatively more side effects were reported with combination therapy, and it must be borne in mind that the risk of retention in this population is low (0.6/100 person years) and the decision about whether to operate is a subjective end point.
Recommendations
The medical therapy of prostatic symptoms trial presents the first evidence that combination therapy for more than a year is better than monotherapy at preventing progression of disease. It suggests that this approach should be adopted in patients at high risk of progression (high prostate volume, high concentration of prostate specific antigen (where prostate cancer has been excluded), or high post void residual urine volume) who also have symptoms. Unfortunately, these are the only data from a randomised controlled trial that are available to support this strategy.
It is important to realise that patients will need to be on combination therapy indefinitely, with only a small improvement in symptom score compared with monotherapy. A population cost-benefit analysis of improving progression of disease has yet to endorse this approach to treatment, and any therapeutic advantage of combination therapy needs to be balanced against the increased side effects and costs.
Several plant extracts have been reported to improve lower urinary tract symptoms due to benign prostatic hyperplasia.21 These include:
Some studies suggest that these extracts are as effective as
antagonists. However, the studies are often poorly designed, and the extracts have not undergone the same scrutiny as conventional drugs for efficacy, purity, and safety. The World Health Organization international consultation on urological disease consensus group does not recommend treatment with these extracts until more robust evidence exists.2
Surgery is performed less often now that effective pharmacotherapy is available, but it is an excellent option for improving symptoms and decreasing progression of disease in patients who develop complications or who have inadequately controlled symptoms on medical treatment.
|
The National Institute for Health and Clinical Excellence produced guidelines to help doctors decide who to refer to secondary care.22 It recommends referring patients with:
Contributors: AKP wrote the article with the help of CRC who recently chaired the World Health Organization committee into the medical treatment of benign prostatic hyperplasia. CRC checked the article for accuracy and relevance, and he ensured that it was up to date and agreed with current guidelines. CRC is guarantor.
Competing interests: CRC has acted as a consultant or received research funding (or both) from Pfizer, Astellas, Abbott, and Recordati Pharmaceuticals. AKP has no competing interests to declare.
-reductase inhibitor dutasteride in the treatment of benign prostatic hyperplasia. Eur Urol 2003;44: 82-8.[CrossRef][ISI][Medline]
![]()
CiteULike
Complore
Connotea
Del.icio.us
Digg
Reddit
Technorati What's this?
Read all Rapid Responses