Combination of phosphodiesterase-5 inhibitors and alpha-blockers in patients with benign prostatic hyperplasia: treatments of lower urinary tract symptoms, erectile dysfunction, or both?

Efficacy and Safety of Combination Comprising Tamsulosin and PDE5-Is, Relative to Monotherapies, in Treating Lower Urinary Tract Symptoms and Erectile Dysfunction Associated With Benign Prostatic Hyperplasia: A Meta-Analysis

We report safety and efficacy of a combination therapy, comprising tamsulosin and phosphodiesterase type 5 inhibitors (PDE5-Is), relative to monotherapy, to ascertain its potential in treating lower urinary tract symptoms (LUTS) and erectile dysfunction (ED) secondary to benign prostatic hyperplasia (BPH) after 3 months’ treatment. We screened MEDLINE, EMBASE, and the Cochrane Controlled Trials Register databases, for randomized controlled trials, and obtained eight articles comprising 1144 participants. Results showed that the combination group had superior outcomes with regard to International Prostate Symptom Score (IPSS) and Qmax, compared to the other two groups. The combination group also had superior efficacy with regard to International Index of Erectile Function (IIEF) than the tamsulosin group, but not over the PDE5-Is group. Further, the combination group showed better efficacy in IPSS voiding and quality of life (QoL) compared to the PDE5-Is group. An analysis of safety outcomes revealed extremely high adverse events (AEs) and pain in the combination group. However, therapy discontinuation due to pain and AEs did not increase with increase in AEs. Overall, our findings indicate that a combination of tamsulosin and PDE5-Is is superior to individual tamsulosin and PDE5-Is monotherapy, with regard to improving LUTS and ED secondary to BPH.

Meta-Analysis of Efficacy and Safety of Tadalafil Plus Tamsulosin Compared with Tadalafil Alone in Treating Men with Benign Prostatic Hyperplasia and Erectile Dysfunction

This meta-analysis was performed to evaluate the efficacy and safety of tadalafil plus tamsulosin compared with tadalafil alone in treating men with benign prostatic hyperplasia (BPH) and erectile dysfunction (ED) after 12 weeks’ treatment. Systematic review was carried out using the Preferred Reporting Items for Systematic Reviews and Meta-analyses. MEDLINE, EMBASE, and the Cochrane Controlled Trials Register were searched to collect randomized controlled trials. The references of related articles were also searched. Four articles including 621 patients were involved in the analysis. The study identified that combination-therapy had significant improvements in total international prostate symptom score (IPSS), quality of life (QoL) and maximum urine flow rate (Qmax) compared with monotherapy, and there were no obvious significance in respects of post-void residual volume, international index of erectile function and IPSS storage. The difference of total IPSS was mainly reflected in the change of IPSS voiding. For safety, combination-therapy had a higher incidence rate of any adverse events (AEs) and discontinuation due to AEs than monotherapy with the exception of pain. In conclusion, the combination of tadalafil and tamsulosin provided a better improvement of IPSS voiding, QoL and Qmax compared with tadalafil alone in treating men with BPH and ED, and the former therapy appeared to show a higher incidence of AEs.

The pharmacology of α1-adrenoceptor subtypes

This review examines the functions of α₁-adrenoceptor subtypes, particularly in terms of contraction of smooth muscle. There are 3 subtypes of α₁-adrenoceptor, α_1A- α_1B- and α_1D-adrenoceptors. Evidence is presented that the postulated α_1L-adrenoceptor is simply the native α_1A-adrenoceptor at which prazosin has low potency. In most isolated tissue studies, smooth muscle contractions to exogenous agonists are mediated particularly by α_1A-, with a lesser role for α_1D-adrenoceptors, but α_1B-adrenoceptors are clearly involved in contractions of some tissues, for example, the spleen. However, nerve-evoked responses are the most crucial physiologically, so that these studies of exogenous agonists may overestimate the importance of α_1A-adrenoceptors. The major α₁-adrenoceptors involved in blood pressure control by sympathetic nerves are the α_1D- and the α_1A-adrenoceptors, mediating peripheral vasoconstrictor actions. As noradrenaline has high potency at α_1D-adrenceptors, these receptors mediate the fastest response and seem to be targets for neurally released noradrenaline especially to low frequency stimulation, with α_1A-adrenoceptors being more important at high frequencies of stimulation. This is true in rodent vas deferens and may be true in vasopressor nerves controlling peripheral resistance and tissue blood flow. The α_lA-adrenoceptor may act mainly through Ca²⁺ entry through L-type channels, whereas the α_1D-adrenoceptor may act mainly through T-type channels and exhaustable Ca²⁺ stores. α₁-Adrenoceptors may also act through non-G-protein linked second messenger systems. In many tissues, multiple subtypes of α-adrenoceptor are present, and this may be regarded as the norm rather than exception, although one receptor subtype is usually predominant.

Effect of tamsulosin on the pharmacokinetics of dutasteride in Chinese male healthy volunteers

The purpose of this study was to evaluate the effect of tamsulosin (0.2 mg) on the pharmacokinetics of dutasteride (0.5 mg) in a group of healthy Chinese male volunteers. This was an open-label, single-sequence, 3-period, drug-drug interaction phase 1 study. Twenty-four healthy Chinese male volunteers were enrolled and administered a single dose of 0.5 mg dutasteride and, following a 28- to 30-day washout period, 0.2 mg tamsulosin once daily for 7 days. On day 5, subjects received 0.2 mg tamsulosin coadministered with 0.5 mg dutasteride. Serum dutasteride and tamsulosin concentrations were monitored. In the presence or absence of tamsulosin, there were no apparent changes in dutasteride AUC and Cmax . Adverse events reported were mild to moderate in intensity and resolved by the end of the study. In healthy Chinese male volunteers, tamsulosin 0.2 mg at steady state had no apparent effect on dutasteride pharmacokinetics. Dutasteride and tamsulosin when administered alone or in combination were well tolerated.

A synopsis of drugs currently in preclinical and early clinical development for the treatment of benign prostatic hyperplasia

INTRODUCTION

Benign prostatic hyperplasia (BPH) is a common disease among men and significantly impacts quality of life by causing lower urinary tract symptoms (LUTS). Current medical therapies are not always adequate in controlling LUTS or slowing disease progression, and there is unmet need for new effective therapeutic options.

AREAS COVERED

The authors review the standard current medical therapies for BPH which include the use of α-1 blockers, 5-α reductase inhibitors, combination therapy and PDE inhibitors. Following this, the authors then discuss new therapies that are currently undergoing preclinical and clinical investigation.

EXPERT OPINION

Existing preclinical and clinical trials have highlighted many promising therapies to treat BPH. Further investigation with larger clinical trials is needed to establish these drugs as standard therapies. As the number of drugs in the arsenal against BPH continues to grow, providers and patients will have to engage in a discussion that weighs the risks and benefits of each therapy.

Oral drug treatments in patients with erectile dysfunction and multiple comorbidities: a retrospective observational study

OBJECTIVE

To investigate factors associated with demographic/clinical characteristics and drug selection in patients with erectile dysfunction (ED). The prevalence of ED is increasing worldwide. Studies have shown that ED is associated with age, lifestyle and comorbidities. However, the factors associated with patient characteristics as well as drug selection are incompletely understood.

SETTING

A tertiary medical centre in Kuala Lumpur, Malaysia.

PARTICIPANTS

A total of 219 patients (range 23-80 years) who had received phosphodiesterase type-5 (PDE-5) inhibitors as ED treatment were evaluated.

INCLUSION CRITERIA

Adult patients aged ≥18 years, diagnosed with ED, and prescribed with sildenafil, tadalafil or vardenafil.

EXCLUSION CRITERIA

Patients diagnosed with ED but who did not receive any PDE-5 inhibitor, or those with missing data.

PRIMARY AND SECONDARY OUTCOME MEASURES

Factors associated with demographic and clinical characteristics as well as drug selection were assessed.

RESULTS

Ischaemic heart disease (p=0.025), benign prostatic hyperplasia (p<0.001), obesity (p=0.005), lower urinary tract symptoms (LUTS) (p=0.006) and α-blockers (p<0.001) were significantly associated with elderly patients with ED. Additionally, LUTS (p=0.038) and α-blockers (p=0.008) were significantly associated with the selection of PDE-5 inhibitor.

CONCLUSIONS

These data showed that elderly patients with ED were significantly associated with comorbidities and α-blockers, whereas LUTS and α blockers were associated with drug selection.

A comparative randomized prospective study to evaluate efficacy and safety of combination of tamsulosin and tadalafil vs. tamsulosin or tadalafil alone in patients with lower urinary tract symptoms due to benign prostatic hyperplasia

INTRODUCTION

Lower urinary tract symptoms (LUTS) associated with benign prostatic hyperplasia (BPH) and erectile dysfunction are common disorders of advancing age.

AIM

To evaluate the efficacy and safety of tamsulosin and tadalafil in patients with LUTS due to BPH.

METHODS

In this prospective randomized study, 133 men complaining of LUTS due to BPH were included. Forty-five patients received tamsulosin 0.4 mg/day alone (Group A), 44 patients received tadalafil 10 mg/day (Group B), and combination therapy (tamsulosin and tadalafil both) was instituted in 44 patients (Group C). After a 2-week medication free run-in period, they were evaluated for International Prostatic Symptom Score (IPSS), International Index of Erectile Function score (IIEF5), quality of life (IPSS QoL), maximum urinary flow rate (Qmax), post-void residual urine (PVR) volume, and safety parameters before and at 3 months of treatment.

MAIN OUTCOME MEASURES

There were primary (IPSS, IPSS QoL index, Qmax, and PVR) and secondary (erectile function [EF] domain scores from IIEF5) efficacy end points. Safety assessment included laboratory tests and patient's reporting of adverse event.

RESULTS

A significant improvement in IPSS score was observed in all the 3 groups A, B, and C (-50.90%, P < 0.05; -33.50%, P < 0.05; and -53.90%, P < 0.05, respectively). IIEF5 score increased significantly in these three groups (+39.28%, P < 0.05; +45.96%, P < 0.05; and +60.23%, P < 0.05, respectively). A significant increase in Qmax and decrease in PVR were also observed (33.99%, P < 0.05; 29.78%, P < 0.05; and 37.04%, P < 0.05) and (-60.90%, P < 0.05; -49.45%, P < 0.05; and -62.97%, P < 0.05, respectively). The QoL scores improved significantly (-73.35%, P < 0.05; -70.26%, P < 0.05; and -79.65%, P < 0.05, respectively). Side effects were dyspepsia, heartburn, headache, flushing, myalgia, and backache. Adverse effect dropout was 3.7%. No participant experienced any severe or serious adverse events.

CONCLUSIONS

In patients with LUTS due to BPH, tamsulosin and tadalafil alone or in combination cause a significant improvement in patients with LUTS. Their EF also improves with these medications. The improvement is better with combination therapy compared with single agent alone.

Udenafil: efficacy and tolerability in the management of erectile dysfunction

Udenafil is a potent novel phosphodiesterase-5 inhibitor approved for use in Korea. Udenafil has unique properties, with a T max of 1.0-1.5 h and a T 1/2 of 11-13 h (a relatively rapid onset and a long duration of action). Therefore, both on-demand and once-daily use of udenafil have been reported. Udenafil's efficacy and tolerability have been evaluated in several studies, and recent and continuing studies have demonstrated udenafil's promise in both dosing regimens. Presently, tadalafil is the only FDA-approved drug for daily dosing, but udenafil can be used as a once-daily dose for erectile dysfunction patients who cannot tolerate tadalafil due to phosphodiesterase subtype selectivity. Udenafil as an on-demand or once-daily dose is effective and tolerable, but more studies are needed in patients of other ethnicities and with comorbid conditions such as diabetes mellitus, hypertension, and benign prostate hyperplasia.

The promise of inhibition of smooth muscle tone as a treatment for erectile dysfunction: where are we now?

Ten years ago, the inhibition of Rho kinase by intracavernosal injection of Y-27632 was found to induce an erectile response. This effect did not require activation of nitric oxide-mediated signaling, introducing a novel target pathway for the treatment of erectile dysfunction (ED), with potential added benefit in cases where nitric oxide bioavailability is attenuated (and thus phosphodiesterase type 5 (PDE5) inhibitors are less efficacious). Rho-kinase antagonists are currently being developed and tested for a wide range of potential uses. The inhibition of this calcium-sensitizing pathway results in blood vessel relaxation. It is also possible that blockade of additional smooth muscle contractile signaling mechanisms may have the same effect. In this review, we conducted an extensive search of pertinent literature using PUBMED. We have outlined the various pathways involved in the maintenance of penile smooth muscle tone and discussed the current potential benefit for the pharmacological inhibition of these targets for the treatment of ED.

Phosphodiesterase type 5 inhibitors in the management of non-neurogenic male lower urinary tract symptoms: critical analysis of current evidence

CONTEXT

A large body of epidemiologic data suggests a causal relationship between lower urinary tract symptoms (LUTS) and erectile dysfunction (ED). Recently reported studies on phosphodiesterase type 5 inhibitors (PDE5-Is) and LUTS have further contributed to the understanding of mechanisms involved in this relationship and of potential treatment options.

OBJECTIVE

A nonsystematic descriptive review was performed to summarize the literature concerning the role of PDE5-Is in men with LUTS, particularly looking at data derived from clinical trials in relation to the different PDE5-Is or their association with α-blockers.

EVIDENCE ACQUISITION

A comprehensive electronic search was conducted in October 2010 using the Medline database to identify all publications relating to ED and BPH and treatment with sildenafil, vardenafil, tadalafil, udenafil, UK-369003, and combination therapy with alfuzosin and tamsulosin.

EVIDENCE SYNTHESIS

In studies in which either ED or LUTS was the entry criterion, sildenafil appears to improve both erectile function and LUTS in subjects with ED. Placebo-controlled trials of tadalafil and vardenafil showed improvement of LUTS secondary to benign prostatic hyperplasia (BPH), but none of the studies showed a significant effect on urodynamic measures. Exploratory studies with UK-369003 showed improvements in LUTS and ED. Sildenafil or tadalafil associated with alfuzosin or tamsulosin showed greater benefits for the combination therapy for both LUTS and ED. The coadministration of udenafil and an α-blocker in patients with BPH and ED also appeared to improve both LUTS and ED severity.

CONCLUSIONS

Consistent evidence of improvements in LUTS has been shown with PDE5-Is, either alone or in combination with α-blockers. However, effects on urodynamics or objective measures of urinary flow are lacking. Further areas of research include investigation of mechanism of PDE5-Is, urodynamic studies, identification of new efficacy end points, head-to-head comparison with standard of care, potential benefit of add-on treatment, and long-term outcomes.

Effectiveness of doxazosin on erectile dysfunction in patients with lower urinary tract symptoms

OBJECTIVE

We evaluated the effectiveness of doxazosin on ED in patients with LUTS/BPH and ED by using symptom score scales. We also evaluated whether or not the presence of asymptomatic inflammatory prostatitis had an effect on the alteration in the symptom scores.

PATIENTS AND METHODS

A total of 36 male patients were included in the study. For all the cases, "International Prostate Symptom Score" (IPSS), "National Health Institute Chronic Prostatitis Symptom Index" (NIH-CPSI) and "International Index of Erectile Function" (IIEF-5) were investigated, and the scores were calculated in the first visit. Doxazosin was given for 30 days, and at the second visit IPSS, NIH-CPSI and IIEF-5 scores, Qmax and PMR were once more analysed. Afterwards, the alterations of the scores between visits were statistically compared.

RESULTS

Mean age of the 36 cases included in the study was 59.03 ± 1.35. The alterations in parameters between 1st and 2nd visit were compared in the cases who used doxazosin and a statistically significant decrease in IPSS, NIH-CPSI scores and statistically significant increase in Qmax were observed. Besides, there was a statistically significant increase in IIEF-5 score. In addition, when the cases were divided into two groups patients with asymptomatic inflammatory prostatitis and without asymptomatic inflammatory prostatitis, there was not any difference in all scores.

CONCLUSION

Doxazocin use in cases with LUTS/BPH and ED has an improving effect on ED as well as LUTS. Therefore, we believe that in the future, single agents or combined therapies might have a place in cases with LUTS/BPH and ED.

Effects of a low-energy diet on sexual function and lower urinary tract symptoms in obese men

OBJECTIVE

Abdominal obesity and type 2 diabetes mellitus are associated with erectile and urinary dysfunction in men. The extent to which sexual function and lower urinary tract symptoms (LUTSs) are improved by weight loss remains unclear.

SUBJECTS

We compared the effects of 8 weeks of a low-calorie diet using meal replacements (Kicstart) on insulin sensitivity, plasma testosterone levels, erectile function (measured by the five-item version of the International Index of Erectile Function, IIEF-5), sexual desire (measured by the Sexual Desire Inventory, SDI) and LUTS (measured by the International Prostate Symptom Score, IPSS), in abdominally obese (body mass index >or=30 kg m(-2), waist circumference (WC) >or=102 cm) men (mean age 49.7 years) with uncomplicated diet or oral hypoglycemic-treated type 2 diabetes mellitus (n = 19) or without type 2 diabetes mellitus (n=25), with a control group of nondiabetic men (n = 26) with similar body mass index and WC.

RESULTS

Weight loss of ∼ 10% was significantly associated with increased insulin sensitivity, plasma testosterone levels, IIEF-5 and SDI scores, as well as reduced WC and IPSS scores, in diabetic as well as nondiabetic men. The degree of weight loss was significantly associated with improvements in plasma testosterone levels (r = -0.34), erectile function (r = -0.26) and LUTS (r=0.65). Reduction in LUTS was significantly associated with increased plasma testosterone (r = -0.35), erectile function (r = -0.42) and sexual desire (r = -0.40).

CONCLUSIONS

Diet-induced weight loss significantly and rapidly improves sexual function, and reduces LUTS, in obese middle-aged men with or without diabetes.

Behaviour modification and benign prostatic hyperplasia: replacement for medications

PURPOSE OF REVIEW

Lower urinary tract symptoms due to benign prostatic hyperplasia (BPH) is a highly prevalent chronic disease. The cost impact of treatment is high. The field of behavioural treatments which could be suitable in the majority of uncomplicated patients has rarely been assessed. We summarize the recent knowledge and data from behavioural interventions chiefly the randomized controlled trial (RCT) of a self-management programme for BPH.

RECENT FINDINGS

The self-management RCT has revealed that a rigorously structured behavioural programme can significantly reduce lower urinary tract symptoms severity and decrease objective symptoms like nocturia, urgency and frequency compared with standard care alone. The elements of the programme and their behavioural framework are carefully defined. The basis of the programme's effectiveness is yet unknown, but may involve changes in bladder capacity rather than simple fluid management. The sphere of behavioural interventions for BPH is lacking and requires more research.

SUMMARY

Elements of the self-management programme are already being used in watchful waiting. Improving quality of life of patients with BPH through self-management will help patients and may reduce the financial burden on healthcare systems. The promotion of multidisciplinary team is a key step in implementing self-management strategies. With larger scale trials, the limitations raised and questions posed by the RCT can be further addressed.

Induction of apoptosis by lupeol and mango extract in mouse prostate and LNCaP cells

Prostate cancer (PCA) is one of the most invasive malignancy and second leading cause of cancer related deaths in United States and some other countries. Long latency period makes PCA an ideal disease for pharmacologic or nutritional chemoprevention. Lupeol, a triterpene present in mango and other fruits, has shown to possess anticancer properties in in vivo and in vitro assays. Here, we recorded the apoptogenic activity in mouse prostate by lupeol and mango pulp extract (MPE). Testosterone was injected subcutaneously (5 mg/kg body weight) for 14 consecutive days to male Swiss albino mice. Lupeol/MPE supplementation resulted in arrest of prostate enlargement in testosterone-treated animals. In mouse prostate tissue, lupeol and MPE supplementation resulted in a significantly high percentage of apoptotic cells in the hypodiploid region. The induction of apoptosis in mouse prostate cells was preceded by the loss of mitochondrial transmembrane potential and DNA laddering. In testosterone-induced mouse prostate, upregulation of antiapoptotic B-cell non-Hodgkin lymphoma-2 and downregulation of proapoptotic Bcl-2-associated X protein and caspase-3 were also recorded. We further observed apoptogenic activities of lupeol in an in vitro model using human prostate cancer cells [lymph node carcinoma of the prostate (LNCaP)]. The apoptogenic response of lupeol-induced changes in LNCaP cells can be summarized as early increase of reactive oxygen species followed by induction of mitochondrial pathway leading to cell death. Thus, the results of this study demonstrate that lupeol/MPE is effective in combating testosterone-induced changes in mouse prostate as well as causing apoptosis by modulating cell-growth regulators.

Common approach to managing lower urinary tract symptoms and erectile dysfunction

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 alpha-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 alpha-adrenergic receptor antagonists (alpha-ARAs) and 5-alpha-reductase inhibitors (5-ARIs) into everyday practice. Treatment with alpha-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 alpha-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.

Lower urinary tract symptoms and sexual dysfunction: a common approach

Alpha(1)-adrenergic blockers (alpha(1)-blockers) are considered the most effective monotherapy for lower urinary tract symptoms (LUTS) suggestive of benign prostatic hyperplasia. Phosphodiesterase type-5 (PDE-5) inhibitors are the first-line treatment for erectile dysfunction (ED). As LUTS and ED are strongly linked, co-prescription of both drug classes is likely to increase. Interaction studies have confirmed that tadalafil, a long-acting PDE-5 inhibitor, has only marginal effects on blood pressure when co-administered with the selective alpha(1)-blockers, alfuzosin or tamsulosin. alpha(1)-blockers show an incidence of ED similar to placebo; they may even have some benefit on sexual function in men with concomitant LUTS and sexual dysfunction, with the exception of tamsulosin which causes anejaculation. On the other hand, PDE-5 inhibitors have a beneficial effect on LUTS. These agents are likely to act via different mechanisms of action, providing the rationale for combining them to treat LUTS and ED. Indeed, alfuzosin and tadalafil show an additive relaxant effect on human detrusor muscle, human prostate tissue and human corpus cavernosum in vitro. A pilot study also suggests that daily intake of alfuzosin 10 mg and sildenafil 25 mg is well tolerated and may be more effective than monotherapy to improve LUTS and ED. Further research is warranted to establish the value of this combination therapy in LUTS and ED.

Is the Current Practice Providing an Integrated Approach to the Management of LUTS and ED in Primary Care? An Audit and Literature Review

INTRODUCTION

Lower urinary tract symptoms (LUTS) and erectile dysfunction (ED) are highly prevalent in aging men. A common pathophysiology is hypothesized to explain causal link. However, prevalence of ED in patients with LUTS remains underdiagnosed, as we believe general practitioners (GPs) do not inquire about ED in men presenting with LUTS.

AIM

Our goal to find out if LUTS and ED were dealt with in an integrated fashion in primary care.

METHODS

One hundred consecutive patients with LUTS attending the prostate assessment clinic anonymously completed a locally developed, qualitatively validated questionnaire and sexual health inventory for men.

MAIN OUTCOME MEASURES

(i) Prevalence of concomitant ED in men presenting with LUTS; (ii) proportion of GPs enquiring about ED; (iii) patients with LUTS + ED who were offered treatment in primary care; and (iv) patients who sought treatment on review in secondary care.

RESULTS

The age of patients was 39-86 years. Fifty-four percent admitted to ED: 66% >/=60 years, and 28% </=60 years had ED. Mean international prostate symptom score in both LUTS +/- ED groups was 16. There was a direct correlation between severity of LUTS and ED. Only 13/54 (24%) admitted ED to their GP. Of the patients, 15.4% received treatment, but 90.9% untreated patients were interested in therapy. Seventy-one percent stated definite reasons for inability to discuss their ED. GPs inquired about ED in only 9.2%. Overall, 66.6% wanted their ED addressed.

CONCLUSIONS

Fifty-four percent of the patients with LUTS also admitted to ED. Patients with more severe LUTS had more severe ED. More than 75% of patients did not report coexistent ED. GPs inquired about ED in only <10% of patients and offered no therapy to more than 80%. Sixty-seven percent of LUTS patients were interested in receiving treatment for ED when offered. A more integrated approach is desired to address the prevalence of ED in patients presenting with LUTS in order to offer them a comprehensive management in primary care.

Daily Administration of Phosphodiesterase Type 5 Inhibitors for Urological and Nonurological Indications

OBJECTIVES

Although the discovery of phosphodiesterases (PDEs) was made soon after the identification of cyclic adenosine monophosphate nearly half a century ago, their true importance in medicine has taken many decades to be realised. The recognition of the important role PDE enzymes play and the impact of altering intracellular cyclic nucleotide levels became significant for most urologists and clinicians in the early 1990s with the discovery of sildenafil, a PDE5 inhibitor (PDE5-I). Once approved around the world, on-demand use of PDE5-Is became the gold standard. Recently, the potential beneficial effects of PDE5-Is on the pulmonary, vascular, and other systems has led to examination of alternative dosing regimens. In this review, we have synthesised the available published peer-reviewed literature to provide a critical contemporary view of evolving indications for PDE5-Is and how alternative dosing regimens may impact on sexual and other functions.

METHODS

MEDLINE search of all peer-reviewed English literature for the period 1990-2007.

RESULTS

The plethora of articles detailing potential uses of PDE5-I in multiple fields of medicine was uncovered. Use of alternative dosing regimens shows great promise across a number of clinical indications, including post-radical retropubic prostatectomy, pulmonary hypertension, endothelial dysfunction, and salvage of on-demand PDE5-I nonresponders.

CONCLUSIONS

Use of PDE5-I on a daily basis may evolve into a major form of drug administration both for men with erectile dysfunction and for those with a myriad of other conditions shown to benefit from this approach.

cGMP-enhancing- and alpha1A/alpha1D-adrenoceptor blockade-derived inhibition of Rho-kinase by KMUP-1 provides optimal prostate relaxation and epithelial cell anti-proliferation efficacy

BACKGROUND

Soluble guanylyl cyclase (sGC)/cyclic guanosine monophosphate (cGMP)/protein kinase G (PKG) and Rho kinase (ROCK2) pathways are important in the regulation of prostate smooth muscle tone. This study is aimed to examine the relaxation activities of a sGC activator and PDE5A/ROCK2 inhibitor KMUP-1 in rat prostate and associated anti-proliferation activity in human prostatic epithelial cells.

METHODS

The action characteristics of KMUP-1 were identified by isometric tension measurement, receptor binding assay, Western blotting and radioimmunoassay in rat prostate. Anti-proliferation activity of KMUP-1 in human prostatic epithelial PZ-HPV-7 cells was identified using flow cytometry and real time QRT-PCR.

RESULTS

KMUP-1 inhibited phenylephrine-induced contractility in a concentration-dependent manner. KMUP-1 possessed potent alpha(1A/)alpha(1D)-adrenoceptor binding inhibition activity, increased cAMP/cGMP levels and increased the expression of sGC, PKG, and PKA protein in rat prostate. Moreover, KMUP-1 inhibited phenylephrine-induced ROCK2 expression. KMUP-1 inhibited cell growth, arrested the cell cycle at G(0)/G(1) phase and increased the expression of p21 in PZ-HPV-7 cells.

CONCLUSIONS

These results broaden our knowledge of sGC/cGMP/PKG and ROCK2 regulation on the relaxation and proliferation of prostate, which may help in the design of benign prostate hyperplasia (BPH) therapies that target these signaling pathways. KMUP-1 possesses the potential benefit in the treatment of BPH by its alpha(1A/)alpha(1D)-adrenoceptor blockade, sGC activation, inhibition of PDE5A and ROCK2 and p21 protein enhancement, leading to attenuation of the smooth muscle tone and the proliferation of epithelial PZ-HPV-7 cells. The synergistic contribution of these pathways by KMUP-1 may benefit BPH patients with lower urinary tract symptoms.

Lower urinary tract symptoms and erectile dysfunction; links for diagnosis, management and treatment

Recent large-scale epidemiological studies have documented a strong association between lower urinary tract symptoms (LUTS) and erectile dysfunction (ED). This observation has two important scientific and clinical aspects: (i) to reveal the pathomechanism linking LUTS and ED and (ii) to consider this fact in the individual approach for diagnosis and management of these two disorders. The following hypotheses are under investigation to explain the relation between LUTS and ED: (i) an increased Rho-kinase activation, (ii) an alpha-adrenergic receptor imbalance, (iii) a decrease of NOS/NO in the endothelium, (iv) atherosclerosis affecting the small pelvis and (v) an autonomic hyperactivity, each affecting simultaneously bladder, prostate and penis. According to a recent randomized trial, sildenafil has a positive effect on LUTS yet not on uroflowmetry in men with LUTS and ED. Although further trials are mandatory, phosphodiesterase-5 inhibitors might play a role in the management of LUTS in the future. alpha-Blockers have no relevant effect on erectile function, tamsulosin leads to retrograde ejaculation in up to 10%. 5alpha-Reductase inhibitors are associated with ED, loss of libido and reduction of ejaculate volume in up to 10%. Transurethral and open prostatectomy induce retrograde ejaculation in up to 90% of patients while their impact on erectile function is still controversially discussed. Minimal invasive treatment options (laser prostatectomy, transurethral microwave thermotherapy) have a lower rate of retrograde ejaculation in the range of 20-70%. LUTS and ED are strongly linked although the exact mechanism is poorly understood. Men seeking for help for LUTS/benign prostatic hyperplasia should be assessed for different aspects of sexual dysfunction and informed regarding the impact of medication and surgery on sexual health.

Combination of alfuzosin and sildenafil is superior to monotherapy in treating lower urinary tract symptoms and erectile dysfunction

OBJECTIVES

This pilot study was undertaken to assess the efficacy and safety of the alpha(1)-blocker alfuzosin 10mg once daily (OD), the PDE-5 inhibitor sildenafil 25mg OD, and the combination of both on lower urinary tract symptoms (LUTS) suggestive of benign prostatic hyperplasia (BPH) and erectile dysfunction (ED).

MATERIAL AND METHODS

Men aged 50-76 yr with previously untreated LUTS and ED were randomized to receive alfuzosin (n=20), sildenafil (n=21), or the combination of both (n=21) for 12 wk. Changes from baseline in International Prostate Symptom Score (IPSS), voiding diary, maximum urinary flow rate (Qmax), postvoid residual urine (PVRU) volume, and erectile function domain of the International Index of Erectile Function (IIEF) were assessed at week 12.

RESULTS

Improvement of IPSS was significant with the three treatments but greatest with the combination (-24.1%) compared with alfuzosin (-15.6%) and sildenafil (-11.8%) [corrected] alone (p<0.03). Frequency, nocturia, PVR, and Qmax were significantly improved with alfuzosin only and the combination. Improvement in IIEF was slight with alfuzosin (16.7%), marked with sildenafil (49.7%), and greatest with the combination (58.6%). Likewise, increases in the frequency of penetration (Q3) and of maintained erection (Q4) were greater with the combination therapy (65.2% and 68.2%, respectively) than with sildenafil (41.7% and 59.1%, respectively) and alfuzosin (27.3% and 33.3%, respectively) alone. All three treatments were well tolerated.

CONCLUSIONS

In this pilot study, the combination of alfuzosin 10 mg OD and sildenafil 25 mg OD is safe and more effective than monotherapy with either agent to improve both voiding and sexual dysfunction in men with LUTS suggestive of BPH.

The role of nitric oxide in mediating tumour blood flow

Nitric oxide (NO) is a ubiquitous molecule with a myriad of physiological and pathophysiological roles. It has numerous direct and indirect effects on tumour vasculature as both a regulatory and effector molecule. NO affects tumour blood flow through its effects on tumour angiogenesis, vascular tone and vascular permeability, partly via its interaction with vascular endothelial growth factor. In this review, the authors examine the basic tenants of NO biology, the association of NO with tumour progression, and the role NO plays in mediating alterations in vascular functions in tumours.