Systematic review and meta-analysis on phosphodiesterase 5 inhibitors and α-adrenoceptor antagonists used alone or combined for treatment of LUTS due to BPH

Comparative efficacy and safety of alpha-blockers as monotherapy for benign prostatic hyperplasia: a systematic review and network meta-analysis

Despite the availability of various drugs for benign prostatic hyperplasia (BPH), alpha(α)-blockers are the preferred first-line treatment. However, there remains a scarcity of direct comparisons among various α-blockers. Therefore, this network meta-analysis (NMA) of randomized controlled trials (RCTs) aimed to evaluate the efficacy and safety of α-blockers in the management of BPH. A comprehensive electronic search covered PubMed, Embase, Ovid MEDLINE, and Cochrane Library until August 2023. The primary endpoints comprised international prostate symptom score (IPSS), maximum flow rate (Qmax), quality of life (QoL), and post-void residual volume (PVR), while treatment-emergent adverse events (TEAEs) were considered as secondary endpoints. This NMA synthesized evidence from 22 studies covering 3371 patients with six kinds of α-blockers with 12 dose categories. IPSS has been considerably improved by tamsulosin 0.4 mg, naftopidil 50 mg and silodosin 8 mg as compared to the placebo. Based on the p-score, tamsulosin 0.4 mg had the highest probability of ranking for IPSS, PVR, and Qmax, whereas doxazosin 8 mg had the highest probability of improving QoL. A total of 297 adverse events were reported among all the α-blockers, silodosin has reported a notable number of TEAEs. Current evidence supports α-blockers are effective in IPSS reduction and are considered safer. Larger sample size with long-term studies are needed to refine estimates of IPSS, QoL, PVR, and Qmax outcomes in α-blocker users.

[Case-based presentation of the S2e guideline on the diagnosis and treatment of benign prostatic hyperplasia]

Benign prostatic hyperplasia (BPH) is the most common disease of the lower urinary tract in men. The prevalence increases continuously with increasing age and a chronic progressive course is to be expected. In order to reduce the morbidity of affected patients and to improve their quality of life, the expert panel Benign Prostatic Hyperplasia (BPH) of the German Society of Urology (DGU) has written a new version of the evidence-based "S2e guideline on the diagnosis and treatment of BPH". Using a current patient case, the contents of the new S2e guideline are illustrated, from diagnosis to the decision-making process for a suitable treatment choice. The case presented here shows the possible complexity and difficulty that can arise in the diagnosis of BPH, the need for further diagnostic steps and the finding of a suitable therapy in order to fulfill the patient's wishes, if possible.

[Conservative and pharmacological treatment of benign prostatic hyperplasia : The German S2e-guideline 2023-part2]

BACKGROUND

Lower urinary tract symptoms (LUTS) suggestive of benign prostatic hyperplasia (BPH, in German guidelines: benign prostatic syndrome [BPS]) is considered the most common disease of the lower urinary tract in men and can have a tremendous impact on the quality-of-life of affected patients. Conservative and pharmacological therapy of this disease are of great importance, both in improving LUTS and reducing progression-related complications.

OBJECTIVES

Presentation of the conservative and pharmacological treatment options according to the current German S2e guideline on BPS.

MATERIALS AND METHODS

Summary and overview of chapters 9 and 10 of the current German S2e guideline on BPS.

RESULTS

In addition to a controlled watchful waiting for BPS patients without an absolute indication for prostate surgery, a variety of phytopharmacological formulations and synthetic drugs according to the symptomatology and clinical progress are available. Phytotherapy should, due to inconsistent study data, only be considered for mild to moderate symptoms. Synthetic drugs include alpha-blockers, 5α-reductase inhibitors, phosphodiesterase inhibitors, antimuscarinics and, more recently, the β3-agonist mirabegron in the current guideline. In addition, various combination therapies are listed and evaluated according to their indications, effects and side effects.

CONCLUSIONS

The current German S2e guideline on the diagnosis and treatment of BPS provides an evidence-based foundation for finding the best possible and most effective medication.

Orthostatic Hypotension in Benign Prostatic Hyperplasia Patients and Its Association With Alpha-1 Antagonist Use: A Comprehensive Literature Review

Orthostatic hypotension (OH) is frequently observed in benign prostatic hyperplasia (BPH) patients undergoing alpha-1 adrenergic antagonist (A1AA) therapy. While previous studies have acknowledged the prevalence of OH in BPH patients on A1AAs, limited data exist on ranking the safety of different A1AAs. This comprehensive review explores the underlying mechanisms of OH, examines numerous factors influencing its development, and provides insights into effective treatment strategies such as hydration, gradual postural changes, leg exercises, compression stockings, and tilt-table training for BPH management. The review highlights the significance of individualized care, interdisciplinary collaboration, and further research to optimize A1AA treatment, improve patient outcomes, and enhance quality of life.

A Review of Combined Phosphodiesterase-5-Inhibitors and α-Blockers versus Phosphodiesterase-5-Inhibitors Alone for Lower Urinary Tract Symptoms due to Benign Prostatic Hyperplasia

Guidelines from the American Urological Association (AUA) and the European Association of Urology (EAU) present conflicting recommendations regarding combination therapy of phosphodiesterase 5 inhibitors (PDE5is) with α-blockers to treat benign prostatic hyperplasia (BPH) with lower urinary tract symptoms (LUTS). Use of PDE5is is widespread in the population of patients with LUTS/BPH. In this scoping review, we examine the evidence regarding the safety and efficacy of combined PDE5is and α-blockers compared to PDE5i medications alone. A search was conducted using PubMed, Cochrane, and Web of Science to identify manuscripts discussing the safety of PDE5i and α-blockers in combination or comparing this combination to PDE5is alone in the treatment of LUTS/BPH. Study designs, data, and conclusions were qualitatively analyzed. Combination therapy was found to be safe across all studies; importantly, no evidence documents increased risk of hypotension. Most studies reported added improvement in symptom and quality of life scores compared to PDE5i alone, with additional International Prostate Symptom Score (IPSS) change ranging from -1.30 to -8.50 and IPSS quality of life score change ranging from -0.15 to -1.50. Objective metrics such as postvoid residual volumes and maximum flow rate were inconsistently reported. Taken together, the current body of data suggests that combining PDE5i α-blocker therapy is safe and that there are opportunities for additional symptomatic improvement, though it should be utilized for select patients. Situations with particular utility could include patients with comorbid erectile dysfunction or without sufficient improvement on monotherapy.

Changes in the expression and function of the PDE5 pathway in the obstructed urinary bladder

Our study aims to explore changes in bladder contractility and the phosphodiesterase type 5 (PDE5) signalling pathway in response to partial bladder outlet obstruction (PBOO). A surgically induced male rat PBOO model and human obstructed bladder tissues were used. Histological changes were examined by H&E and Masson's trichrome staining. Bladder strip contractility was measured via organ bath. The expressions of nitric oxide synthase (NOS) isoforms, PDE5, muscarinic cholinergic receptor (CHRM) isoforms and PDE4 isoforms in bladder were detected by RT‐PCR and Western blotting. The immunolocalization of the PDE5 protein and its functional activity were also determined. PBOO bladder tissue exhibited significant SM hypertrophy and elevated responsiveness to KCl depolarization and the muscarinic receptor agonist carbachol. NOS isoforms, PDE5, CHRM2, CHRM3 and PDE4A were up‐regulated in obstructed bladder tissue, whereas no change in PDE4B and PDE4D isoform expression was observed. With regard to PDE5, it was expressed in the SM bundles of bladder. Interestingly, obstructed bladder exhibited less relaxation responsiveness to sodium nitroprusside (SNP), but an exaggerated PDE5 inhibition effect. The up‐regulation of PDE5 could contribute to the lack of effect on Q_max for benign prostatic hyperplasia/lower urinary tract symptom (BPH/LUTS) patients treated with PDE5 inhibitors. Moreover, PDE5 (with presence of NO) and PDE4 may serve as new therapeutic targets for bladder diseases such as BPH‐induced LUTS and overactive bladder (OAB).

Drugs for benign prostatic hypertrophy

Benign prostatic hyperplasia is a common condition It can cause problems with urine storage and voiding and the severity of symptoms may be unrelated to the size of the prostate

When drug treatment is required benign prostatic hyperplasia can be managed with monotherapy or combination therapy Most patients are managed with selective alpha blockers

Patients with larger prostate volumes may benefit from a 5-alpha-reductase inhibitor usually in combination with an alpha blocker

Alpha-blockers with or without phosphodiesterase type 5 inhibitor for treatment of lower urinary tract symptoms secondary to benign prostatic hyperplasia: a systematic review and meta-analysis

PURPOSE

Recently, several randomized controlled trials (RCTs) explored the effects of α-blockers with or without phosphodiesterase type 5 inhibitors (PDE5-Is) for lower urinary tract symptoms secondary to benign prostatic hyperplasia (LUTS/BPH). However, the results were inconsistent. We performed this meta-analysis to evaluate the role of combination therapy (α-blockers and PDE5-Is) in patients with LUTS/BPH.

MATERIALS AND METHODS

Databases including PubMed, Cochrane library, Web of Science, and Embase were searched for qualified RCTs. Pooled mean differences (MDs) and odds ratios (ORs) were calculated to measure the effects and adverse events in combination therapy. Moreover, subgroup analyses of ethnicity, dosage of PDE5-Is, treatment duration, and severity of LUTS/BPH were performed. In addition, trial sequential analyses (TSAs) were used to assess whether the evidence for the results was sufficient.

RESULTS

Overall, this study identified 11 eligible RCTs, including 855 LUTS/BPH patients. Patients receiving combination therapy had better improvement in international prostate symptom score (IPSS: MD: 1.66, 95% CI - 3.03 to - 0.29), maximum urinary flow rate (Q_max: MD: 0.94, 95% CI 0.24-1.64), and international index of erectile function (IIEF: MD: 4.73, 95% CI 2.95-6.51), comparing those without PDE5-Is. Besides, subgroup analyses indicated that the effects of combination treatment were associated with ethnicity, treatment duration, and severity of LUTS/BPH. By TSA, the findings in the current study were based on sufficient evidence.

CONCLUSIONS

Our results indicated that combination therapy can significantly improve IPSS, Q_max, and IIEF in patients with LUTS/BPH. Combination therapy might be more suitable for these patients.

Efficacy and safety of PDE5-Is and α-1 blockers for treating lower ureteric stones or LUTS: a meta-analysis of RCTs

BACKGROUND

Lower ureteric stones and lower urinary tract symptoms are common in urology.Drug treatment is one of standard therapy,but the efficacy was controversial.Thus we aimed to investigate the efficacy and safety of monotherapy or combination therapy of adrenoceptor1 blockers and phosphodiesterase5 inhibitors for treatment.

METHODS

Randomized controlled trials up to November 2016 were retrieved from PubMed, the Cochrane Library, Web of Science and Embase. A total of 17 studies were included. We analyzed data through random or fixed effect models. The heterogeneity between studies was assessed by the I² test statistic.

RESULTS

As for lower ureter stones, our analysis demonstrated tadalafil had a significantly lower incidence of abnormal ejaculation than adrenoceptor1 blockers (2.31 95%CI 0.22to0.84, P = 0.01),while combination therapy had a higher expulsion rate (2.49 95%CI 1.44to4.29, P = 0.001) and shorter expulsion time (- 1.98 95%CI -3.08to0.88, P = 0.0004) than tamsulosin. As for lower urinary tract symptoms, our analysis indicated adrenoceptor1 blockers was more effective than phosphodiesterase5 inhibitors on decreasing International Prostate Symptom Score (1.96 95%CI 0.03to3.89, P = 0.05) and Post-Void Residual (9.41 95%CI 1.40to14.41, P = 0.02) and phosphodiesterase5 inhibitors showed a greater effect than adrenoceptor1 blockers on improving Erectile Dysfunction (2.23 95%CI 1.24to3.22, P<0.0001).Combination therapy had a significantly better effect on International Prostate Symptom Score (1.47 95%CI 1.25to1.69, P<0.0001), Maximum flow rate (0.87 95%CI 0.71to1.04, P<0.0001), Post-Void Residual (10.74 95%CI 3.53to17.96,P = 0.004) and Quality of life (0.59 95%CI 0.22to0.97, P = 0.002) but was associated with higher incidences of adverse events (3.40 95%CI 1.82to6.36, P = 0.0001) than adrenoceptor1 blockers. Combination therapy had a significantly better effect on International Prostate Symptom Score (4.19 95%CI 3.34to5.04, P<0.0001), Maximum flow rate (1.86 95%CI 1.32to2.39, P<0.0001), Post-Void Residual (22.58 95%CI 9.13to36.04, P = 0.001) and Quality of life (0.68 95%CI 0.37to1.00, P<0.0001) without higher incidences of adverse events than PDE5-Is.

CONCLUSIONS

In conclusion, this meta-analysis suggested combination therapy had a best efficacy of therapy for lower ureteric stones or lower urinary tract symptoms correlated with benign prostatic hyperplasia than monotherapy. Adrenoceptor1 blockers was more effective than phosphodiesterase5 inhibitors on International Prostate Symptom Score and Post-Void Residual. Both monotherapy and combination therapy were safe.

The BPSC: A prospective study investigating the clinical effect of interventional therapy and the risk factors for bladder cancer and benign prostatic hyperplasia in Chinese population

Bladder cancer and benign prostatic hyperplasia have been two very common diseases among the elderly men, especially with the aging of the population in the world. We have designed a study to investigate the clinical effect of interventional therapy for plasmakinetic resection of the prostate and plasmakinetic resection of the bladder, which is called "BPSC" (The bladder cancer and benign prostatic hyperplasia study in Chinese population). The BPSC is not only a specific study, it is made up of many studies. In this article, we introduced the research background, source, name, study framework, study management and further direction of BPSC project. We hope this process will contribute to the growth of the database through sharing data and enriching the evidence of bladder cancer and benign prostatic hyperplasia in the Chinese population, thereby finally improving the accessibility of these important findings for doctors, researchers, and patients.

Novel imaging of the prostate reveals spontaneous gland contraction and excretory duct quiescence together with different drug effects

Prostate carcinoma and benign prostate hyperplasia (BPH) with associated lower urinary tract symptoms (LUTS) are among the most prevalent and clinically relevant diseases in men. BPH is characterized by an enlargement of prostate tissue associated with increased tone of smooth muscle cells (SMCs) which surround the single glands composing the prostate. Secretions of the glands leave the prostate through local excretory ducts during the emission phase of ejaculation. Pharmacological treatment of BPH suggests different local drug targets based on reduction of prostate smooth muscle tone as the main effect and disturbed ejaculation as a common side effect. This highlights the need for detailed investigation of single prostate glands and ducts. We combined structural and functional imaging techniques-notably, clear lipid-exchanged, acrylamide-hybridized rigid imaging/immunostaining/ in situ hybridization-compatible tissue-hydrogel (CLARITY) and time-lapse imaging-and defined glands and ducts as distinct SMC compartments in human and rat prostate tissue. The single glands of the prostate (comprising the secretory part) are characterized by spontaneous contractions mediated by the surrounding SMCs, whereas the ducts (excretory part) are quiescent. In both SMC compartments, phosphodiesterase (PDE)-5 is expressed. PDE5 inhibitors have recently emerged as alternative treatment options for BPH. We directly visualized that the PDE5 inhibitors sildenafil and tadalafil act by reducing spontaneous contractility of the glands, thereby reducing the muscle tone of the organ. In contrast, the ductal (excretory) system and thus the prostate's contribution to ejaculation is unaffected by PDE5 inhibitors. Our differentiated imaging approach reveals new details about prostate function and local drug actions and thus may support clinical management of BPH.-Kügler, R., Mietens, A., Seidensticker, M., Tasch, S., Wagenlehner, F. M., Kaschtanow, A., Tjahjono, Y., Tomczyk, C. U., Beyer, D., Risbridger, G. P., Exintaris, B., Ellem, S. J., Middendorff, R. Novel imaging of the prostate reveals spontaneous gland contraction and excretory duct quiescence together with different drug effects.

Efficacy and Safety of a Fixed-Dose Combination Therapy of Tamsulosin and Tadalafil for Patients With Lower Urinary Tract Symptoms and Erectile Dysfunction: Results of a Randomized, Double-Blinded, Active-Controlled Trial

BACKGROUND

Phosphodiesterase type 5 inhibitors and α-adrenergic blocking agents (α-blockers) are widely used for the treatment of erectile dysfunction (ED) and lower urinary tract symptoms (LUTS) associated with benign prostatic hyperplasia (BPH).

AIMS

To assess the efficacy and safety of fixed-dose combinations (FDCs) of tamsulosin and tadalafil compared with tadalafil monotherapy in patients with comorbid BPH-associated LUTS and ED.

METHODS

A randomized, double-blinded, active-controlled trial was conducted of 510 men with BPH-associated LUTS and ED. Patients were treated with FDCs of tamsulosin 0.4 mg plus tadalafil 5 mg (FDC 0.4/5 mg), tamsulosin 0.2 mg plus tadalafil 5 mg (FDC 0.2/5 mg), or tadalafil 5 mg for a 12-week treatment period. For a subsequent 12-week extension period, the patients were administered FDC 0.4/5 mg.

OUTCOMES

The primary outcomes were changes from baseline in total International Prostate Symptom Score (IPSS) and International Index of Erectile Function erectile function domain (IIEF-EF) score at week 12 to prove superiority and non-inferiority of FDCs compared with tadalafil 5 mg. The safety assessments were adverse reactions, laboratory test results, and vital signs at week 24.

RESULTS

The mean changes in total IPSS and IIEF-EF scores were -9.46 and 9.17 for FDC 0.4/5 mg and -8.14 and 9.49 for tadalafil 5 mg, respectively, which indicated superiority in LUTS improvement (P = .0320) and non-inferiority in ED treatment with FDC 0.4/5 mg compared with tadalafil 5 mg. However, the results from FDC 0.2/5 mg failed to demonstrate superiority in LUTS improvement. No clinically significant adverse events regarding the investigational products were observed during the 24-week period.

CLINICAL IMPLICATIONS

The FDC 0.4/5 mg is the first combined formulation of an α-blocker and a phosphodiesterase type 5 inhibitor that offers benefits in patient compliance and as add-on therapy in patients with comorbid BPH-associated LUTS and ED.

STRENGTHS AND LIMITATIONS

The study clearly demonstrated the advantage of FDC 0.4/5 mg. The main advantage of FDC 0.4/5 mg was the enhanced efficacy on BPH-associated LUTS comorbidity with ED, the lower incidence of side effects, and the simplification and convenience of therapy, which led to better overall patient compliance. However, the lack of a tamsulosin monotherapy control group was a limitation of this study.

CONCLUSION

The FDC 0.4/5 mg therapy was safe, well tolerated, and efficacious, indicating that combination therapy could provide clinical benefits for patients with BPH-associated LUTS complaints and ameliorate the comorbidity of ED. Kim SW, Park NC, Lee SW, et al. Efficacy and Safety of a Fixed-Dose Combination Therapy of Tamsulosin and Tadalafil for Patients With Lower Urinary Tract Symptoms and Erectile Dysfunction: Results of a Randomized, Double-Blinded, Active-Controlled Trial. J Sex Med 2017;14:1018-1027.

Safety and efficacy of tamsulosin, alfuzosin or silodosin as monotherapy for LUTS in BPH - a double-blind randomized trial

INTRODUCTION

Currently alpha1-adrenoceptor blockers (AB) are widely used as first-line therapy to improve lower urinary tract symptoms (LUTS) associated with benign prostatic hyperplasia (BPH). We compared the efficacy and safety profile of tamsulosin, alfuzosin and silodosin in LUTS due to BPH.

MATERIAL AND METHODS

Consecutive consenting male patients (N = 269) undergoing medical management of BPH with AB from February 2012 to October 2015 were enrolled. Patients were randomized to a 0.4 mg tamsulosin (group T), 10 mg alfuzosin (group A) or a 8 mg silodosin (group S) by double-blind randomization. All patients were assessed for improvements and post-void residual urine (PVR) and for adverse drug events (ADE).

RESULTS

IPSS showed significant improvement in Group S at the first week (11.7 ±4.18, p = 0.027) and at 3 months (7.97 ±3.84, p = 0.020). QOL showed significant improvement at 1 (2.2 ±0.76, p = 0.020), 4 (1.47 ±0.63, p <0.001) and 12 (1.2 ±0.66, p <0.001) weeks in Group S. The mean Qmax improvement was the maximum (13.76 ±2.44, p = 0.028) in Group S at 1 week. Reduction in PVR was the maximum in Group S, but it was not statistically significant. Adverse drug events (ADE) were observed in 20.07% (54/269) patients and distribution was similar in the three groups with decreasing incidence with progression of time.

CONCLUSIONS

Silodosin is the most efficacious AB with rapid onset of action. Silodosin also improves the quality of life in patients with LUTS due to BPH and objectively improves maximum flow rate. However, silodosin has more adverse events when compared to tamsulosin and alfuzosin.

New therapeutic strategies for the treatment of male lower urinary tract symptoms

Male lower urinary tract symptoms (LUTS) are prevalent in the general population, especially in those of advanced age, and are characterized by notable diversity in etiology and presentation, and have been proven to cause various degrees of impairment on quality of life. The prostate has traditionally been regarded as the core cause of male LUTS. As a result, medical treatment aims to provide symptomatic relief and effective management of progression of male LUTS due to benign prostatic enlargement. In this context, α₁-blockers, phosphodiesterase-5 inhibitors, and 5α-reductase inhibitors have long been used as monotherapies or in combination treatment to control voiding LUTS. There is accumulating evidence, however, that highlights the role of the bladder in the pathogenesis of male LUTS. Current research interests have shifted to bladder disorders, and medical management is aimed at the bladder. Muscarinic receptor antagonists and the newly approved β₃-adrenergic agonist mirabegron aim to alleviate the most bothersome storage LUTS and thus improve quality of life. As voiding and storage LUTS frequently coexist, combination therapeutic strategies with α₁-blockers and antimuscarinics or β₃-agonists have been introduced to manage symptoms effectively. Anti-inflammatory agents, vitamin D₃-receptor analogs, and cannabinoids represent treatment modalities currently under investigation for use in LUTS patients. Furthermore, luteinizing hormone-releasing hormone antagonists, transient receptor-potential channel blockers, purinergic neurotransmission antagonists, Rho-kinase inhibitors, and inhibitors of endothelin-converting enzymes could have therapeutic potential in LUTS management, but still remain in the experimental setting. This article reviews new strategies for the medical treatment of male LUTS, which are dictated by the potential role of the bladder and the risk of benign prostatic hyperplasia progression. Moreover, combination treatments and therapies currently under investigation are also presented.

Pharmacological modulation of ureteric peristalsis in a chronically instrumented conscious pig model: effect of adrenergic and nitrergic modulation

PURPOSE

To evaluate the role of adrenergic and nitrergic signaling on ureteric peristaltic frequency and contraction force in vivo using a large animal model.

METHODS

Twelve female pigs (72 ± 4 kg) were chronically instrumented with an electronic pressure-monitoring catheter in the right ureter. Nephrostomy, cystostomy, and arterial and venous catheters were left in situ. Ureteral peristalsis was recorded before and after the administration of propranolol, isoprenaline, doxazosin, urapidil, phenylephrine, LNNA (Nω-nitro-L-arginine), and L-arginine.

RESULTS

α1-Adrenergic receptor stimulation resulted in an increased P max and peristaltic frequency. However, α1-inhibition decreased P max alone. Similarly, β-adrenergic stimulation decreased P max and peristaltic frequency, whereas β-inhibition increased only P max. LNNA administration increased P max in the distal ureter and hydrostatic pressure in the pyelocalyceal system. L-Arginine did not affect P max or frequency, but resulted in a significantly higher diuresis. Either agonist or antagonist of NO did not affect peristaltic frequency and length of contraction.

CONCLUSIONS

Activation of α- and β-adrenergic receptors, respectively, stimulates and inhibits ureteric peristalsis. The biological effect of NO on ureteric motility is regionally determined and corresponds to the distribution of NOS-positive nerves. Inhibition of NOS activity increases P max in the distal ureter and tonic activity of the ureteric muscle resulting in higher hydrostatic pressure in the renal pelvis.