Doxazosin for benign prostatic hyperplasia: long-term efficacy and safety in hypertensive and normotensive patients. The Multicenter Study Group

Role of α1-blockers in the current management of hypertension

There is emerging evidence that α1-blockers can be safely used in the treatment of hypertension. These drugs can be used in almost all hypertensive patients for blood pressure control. However, there are several special indications. Benign prostatic hyperplasia is a compelling indication of α1-blockers, because of the dual treatment effect on both high blood pressure and lower urinary tract symptoms. Many patients with resistant hypertension would require α1-blockers as add-on therapy. Primary aldosteronism screen is a rapidly increasing clinical demand in the management of hypertension, where α1-blockers are useful for blood pressure control in the preparation for the measurement of plasma aldosterone and renin. Nonetheless, α1-blockers have to be used under several considerations. Among the currently available agents, only long-acting α1-blockers, such as doxazosin gastrointestinal therapeutic system 4-8 mg daily and terazosin 2-4 mg daily, should be chosen. Orthostatic hypotension is a concern with the use of α1-blockers especially in the elderly, and requires careful initial bedtime dosing and avoiding overdosing. Fluid retention is potentially also a concern, which may be overcome by combining an α1-blocker with a diuretic.

Data-driven methodology for discovery and response to pulmonary symptomology in hypertension through statistical learning and data mining: Application to COVID-19 related pharmacovigilance

Background: Potential therapy and confounding factors including typical co-administered medications, patient's disease states, disease prevalence, patient demographics, medical histories, and reasons for prescribing a drug often are incomplete, conflicting, missing, or uncharacterized in spontaneous adverse drug event (ADE) reporting systems. These missing or incomplete features can affect and limit the application of quantitative methods in pharmacovigilance for meta-analyses of data during randomized clinical trials.

Methods: Data from patients with hypertension were retrieved and integrated from the FDA Adverse Event Reporting System. 134 antihypertensive drugs out of 1151 drugs were filtered and then evaluated using the Empirical Bayes Geometric Mean (EBGM) of the posterior distribution to build ADE-drug profiles with an emphasis on the pulmonary ADEs (pADE). Afterward, the Graphical Least Absolute Shrinkage and Selection Operator (GLASSO) captured drug associations based on pADEs by correcting hidden factors and confounder misclassification. Selected drugs were then compared using the Friedman test in drug classes and clusters obtained from GLASSO.

Results: Following multiple filtering stages to exclude insignificant and noise-driven reports, we found that drugs from antihypertensives agents, urologicals, and antithrombotic agents (macitentan, bosentan, epoprostenol, selexipag, sildenafil, tadalafil, and beraprost) form a similar class with a significantly higher incidence of pADEs. Macitentan and bosentan were associates with 64% and 56% of pADEs, respectively. Because these two medications are prescribed in diseases affecting pulmonary function and may be likely to emerge among the highest reported pADEs, in fact, they serve to validate the methods utilized here. Conversely, doxazosin and rilmenidine were found to have the least pADEs in selected drugs from hypertension patients. Nifedipine and candesartan were also found by signal detection methods to form a drug cluster, shown by several studies an effective combination of these drugs on lowering blood pressure and appeared an improved side effect profile in comparison with single-agent monotherapy.

Conclusions: We consider pADE profiles in multiple long-standing groups of therapeutics including antihypertensive agents, antithrombotic agents, beta-blocking agents, calcium channel blockers, or agents acting on the renin-angiotensin system, in patients with hypertension associated with high-risk for COVID-19. We found that several individual drugs have significant differences between their drug classes and compared to other drug classes. For instance, macitentan and bosentan from endothelin receptor antagonists show major concern while doxazosin and rilmenidine exhibited the least pADEs compared to the outcomes of other drugs. Using techniques in this study, we assessed and confirmed the hypothesis that drugs from the same drug class could have very different pADE profiles affecting outcomes in acute respiratory illness.

Funding: GJW and MJD accepted funding from BioNexus KC for funding on this project, but BioNexus KC had no direct role in this article.

Identification and functional activity of matrix-remodeling associated 5 (MXRA5) in benign hyperplastic prostate

Objective: Benign prostatic hyperplasia (BPH) is a common condition in aging males. The current study aims to identify differentially expressed genes (DEGs) associated with BPH and to elucidate the role of matrix-remodeling associated 5 (MXRA5) protein and mitogen-activated protein kinase (MAPK) signaling pathways in BPH.

Results: A total of 198 DEGs and a number of related pathways were identified with MXRA5 being one of the most significantly altered DEGs. MXRA5 was upregulated in BPH samples and localized mostly in stroma. Knockdown of MXRA5 induced stromal cell cycle arrest instead of inhibiting apoptosis. Consistently, MXRA5 overexpression enhanced epithelial cell proliferation. In addition, phosphorylated ERK1/2 and p38, key members of the MAPK family, were strongly decreased with knockdown but increased with overexpression.

Conclusion: Our novel data demonstrates that upregulation of MXRA5 in the enlarged prostate could contribute to the development of BPH through increasing cell proliferation via the MAPK pathway. Thus, the MXRA5-MAPK system could be rediscovered as a new therapeutic target for treating BPH.

Methods: Microarray analysis and integrated bioinformatics were conducted. The expression and biologic functions of MXRA5 was investigated via RT-PCR, western-blot, immunofluorescence, flow cytometry and MTT assay. Finally, genes involved in regulation of the MAPK pathway were investigated.

Nocturia: The circadian voiding disorder

Nocturia is a prevalent condition of waking to void during the night. The concept of nocturia has evolved from being a symptomatic aspect of disease associated with the prostate or bladder to a form of lower urinary tract disorder. However, recent advances in circadian biology and sleep science suggest that it might be important to consider nocturia as a form of circadian dysfunction. In the current review, nocturia is reexamined with an introduction to sleep disorders and recent findings in circadian biology in an attempt to highlight the importance of rediscovering nocturia as a problem of chronobiology.

Intravesical Prostatic Protrusion: A Potential Marker of Alpha-blocker Treatment Success in Patients With Benign Prostatic Enlargement

OBJECTIVE

To investigate the value of anatomic and blood-flow measurements of the prostate via ultrasound in identifying medical treatment response of patients with lower urinary tract symptoms due to benign prostatic enlargement. A secondary objective of the study was to compare transabdominal-transrectal measurements.

MATERIALS AND METHODS

Male patients (age range 50-80) with lower urinary tract symptoms who applied to our outpatient clinic to be diagnosed with benign prostatic enlargement that were eligible for medical management were included in the prospective study. Patients (n = 49) were administered with tamsulosin for management. At baseline evaluation, all patients underwent International Prostate Symptom Score (IPSS), prostate-specific antigen (PSA), transabdominal and transrectal ultrasound [prostate volume (PV), post-void rezidu and intravesical prostatic protrusion (IPP)], and prostate subcapsular resistive index value measurement. Follow-ups were carried out 1 and 3 months after treatment. At these time-points, patients were assessed with IPSS and uroflowmetry.

RESULTS

IPP were identified to be negatively correlated with baseline Qmax values (P = .001, R = -0.485) and positively correlated with PSA (P = .013, R = 0.353) and PV (P = .003, R = 0.420). PV was related with resistive index (P = .026, R = 0.318) and PSA (P = .001, R = 0.619). Subsequent to medical treatment on the follow-ups, an overall improvement in the IPSS and Qmax was identified (P = .001). However, a negative correlation was identified in the change that occurred between IPSS and IPP (P = .004, R = -0.410). Other parameters were not correlated (P > .05) with the change in IPSS and Qmax. Transabdominal and transrectal measures were similar (P = .001).

CONCLUSION

This study has shown that increased IPP values are associated with lower response to alpha-receptor specific management. Transabdominal measurements are sufficient for the evaluation compared with transrectal measurement.

Effects of Doxazosin on Alpha 1-Adrenergic Receptors in Prostates with Benign Prostatic Hyperplasia

OBJECTIVES

The present study aimed to evaluate changes in mRNA and protein expression levels of α1-AR before and after doxazosin treatment.

METHODS

This 12-month, prospective study included males aged 50 or older who had lower urinary tract symptoms (LUTS) (International Prostate Symptom Score [IPSS] ≥ 8) with benign prostatic hyperplasia (BPH). All patients underwent transrectal ultrasound-guided prostate biopsy before and after doxazosin 4 mg medication for 12 months. The mRNA and protein expression of prostate α1-AR were analyzed using real-time quantitative reverse transcription-polymerase chain and Western blotting, respectively, before and after treatment. The clinical efficacy of doxazosin was evaluated according to changes in prostate volume, serum prostate-specific antigen (PSA) level, IPSS, quality of life (QoL) index, maximum flow rate, parameters in a voiding diary, and a Patient's Perception of Bladder Condition (PPBC) questionnaire.

RESULTS

Twenty patients aged 50-72 (median age 66) with LUTS secondary to BPH completed this study. Administering doxazosin for 12 months significantly increased α1-AR protein expression in the prostate. α1-AR mRNA expression did not change significantly after doxazosin administration. IPSS, QoL index, and PPBC scores significantly improved after 12 months of doxazosin treatment. Maximal flow rate, postvoid residual urine volume (PVR), prostate volume and the parameters from the voiding diary did not change significantly after 12 months. The change of IPSS total score and LUTS were maintained until 12 months after starting treatment with doxazosin.

CONCLUSION

Doxazosin treatment was able to increase α1-AR protein expression in the prostate. Despite increased α1-AR expression, doxazosin provides sustained, significant relief of LUTS for up to one year without a decrease in efficacy.

Hemodynamic Interaction Between a Daily Dosed Phosphodiesterase 5 Inhibitor, Tadalafil, and the α-Adrenergic Blockers, Doxazosin and Tamsulosin, in Middle-Aged Healthy Male Subjects

The hemodynamic interaction between tadalafil (5 mg/d) and doxazosin or tamsulosin was investigated in 2 randomized, double-blind, crossover phase 1 studies. Healthy men (n = 45) received tadalafil or placebo for 28 days and increasing doses of doxazosin (1, 2, and 4 mg/d) for the last 21 days of treatment. In the second study, participants (n = 39) received tadalafil or placebo for 14 days and tamsulosin (0.4 mg/d) for the last 7 days of treatment. Similar mean maximum postbaseline changes in standing systolic blood pressure were observed in subjects given tadalafil or placebo with 4 mg of doxazosin (-0.5 mm Hg; 95% confidence interval, -4 to 3.1 mm Hg) or with tamsulosin (0.9 mm Hg; 95% confidence interval, -1.4 to 3.2 mm Hg). Standing systolic blood pressure less than 85 mm Hg (blood pressure outlier) occurred in 1 subject treated with 4 mg of doxazosin plus tadalafil but was not reported in subjects treated with tamsulosin and tadalafil. Three subjects experienced moderate hypotensive events lasting less than 2 hours, 2 with syncope (after tadalafil alone or with 4 mg of doxazosin) and 1 without (after 4 mg of doxazosin with placebo). The incidence of hypotension was low in healthy men given increasing doses of doxazosin with chronically dosed tadalafil or placebo. Administration of tadalafil with tamsulosin was well tolerated in healthy men.

Outcomes and quality of life issues in the pharmacological management of benign prostatic hyperplasia (BPH)

BACKGROUND

Benign prostatic hyperplasia (BPH) is a common disease of the aging male population. BPH treatment includes a variety of pharmacological and surgical interventions. The goal of this paper is to review the natural history of BPH, outcomes of pharmacological management, effects on quality of life (QoL), future pharmacotherapies, and associated patient-focused perspectives.

MATERIALS AND METHODS

Medline searches for the keywords benign prostatic hyperplasia, BPH, alpha blockers, 5 alpha-reductase, and quality of life were performed. Relevant literature was reviewed and analyzed.

RESULTS

Alpha blockers, 5 alpha-reductase inhibitors, and phytotherapy are the three categories of pharmaceutical interventions currently available for BPH. Various clinical trials have shown that alpha blockers and 5 alpha-reductase inhibitors are safe, efficacious, and improve QoL in patients with BPH. The evidence for phytotherapeutics is not as convincing. The current armamentarium of pharmaceutical interventions are encompassed in these three classes of medications. New pharmacotherapies based on novel mechanisms are on the horizon.

CONCLUSION

There are a variety of safe and efficacious medical therapies available for the management of BPH and it is important for the practicing physician to have an understanding of these pharmacotherapies and their potential impact on the patient. There is not enough evidence to make a recommendation regarding phytotherapy use. New classes of drugs for BPH will likely find their way into routine use.

Benign prostatic hyperplasia

This article reviews the epidemiology of benign prostatic hyperplasia (BPH), evaluation of patients with lower urinary tract symptomatology (LUTS), and management of patients with BPH and LUTS. The evaluation includes history and physical examination, laboratory testing, and specialized studies. The management includes medical and surgical options. Medical options include alpha-1-adrenergic receptor blockers, 5alpha-reductase inhibitors, and combinations of these and other medications. Surgical options include endoscopic procedures, open procedures, and laser procedures.

Pharmacokinetics of Doxazosin Gastrointestinal Therapeutic System after Multiple Administration in Korean Healthy Volunteers

Doxazosin mesylate is a selective alpha-adrenoreceptor antagonist for the treatment of hypertension and benign prostatic hyperplasia. A simple high performance liquid chromatographic method has been developed and validated for the quantitative determination of doxazosin in plasma. A reversed phase C18 column was used for the separation of doxazosin and prazosin (internal standard) with a mobile phase composed of water, acetonitrile, triethylamine (68:32:0.2 v/v, pH 5.0) at a flow rate of 1.2 mL/min. The fluorescence detector was operated at 246 (excitation) and 389 nm (emission). Intra- and inter-day precision and accuracy were acceptable for all quality control samples including the lower limit of quantification of 1 ng/mL. Recovery of doxazosin from human plasma was greater than 93.4%. Doxazosin was stable in human plasma under various storage conditions. This method was used successfully for a pharmacokinetic study in plasma after oral administration of multiple 4-mg dose of doxazosin gastrointestinal therapeutic system formulation to 16 healthy volunteers. At steady state the mean area under the curve for a dosing interval and elimination half-life were calculated to be 367.0 +/- 63.5 ng x hr/mL and 29.2 +/- 4.5 hr, respectively. There was no difference in pharmacokinetic parameters between male and female.

Bioequivalence Evaluation of Two Formulations of Doxazosin Tablet in Healthy Thai Male Volunteers

The bioequivalence of two doxazosin 2 mg tablets was determined in 24 healthy Thai male volunteers after one single dose in a randomized cross-over study with a one week washout period. The study was conducted at Faculty of Pharmaceutical Sciences and Health Sciences Research Institute, Naresuan University, Phitsanulok, Thailand. Reference (Cardura, Heinrich Mack Nachf. GmbH & Co. GK, Illertissen, Germany) and test (Dozozin-2, Umeda Co., Ltd., Bangkok Thailand) were administered to volunteers after overnight fasting. Blood samples were collected at specified time intervals and plasma was separated. The validated HPLC method with fluorescence detection was used for quantification of doxazosin in plasma samples. The pharmacokinetic parameters, T(max), C(max), AUC(t), AUC(infinity), T(1/2), lambda(z), Cl and V(d), were determined from plasma concentration time profile of both formulations by using non-compartment analysis. The calculated pharmacokinetic parameters were compared statistically to evaluate bioequivalence between the two brands. The analysis of variance (ANOVA) using log-transformed C(max), AUC(t), and AUC(infinity) did not show any significant difference between two formulations. The point estimates and 90% confidence intervals for C(max), AUC(t) and AUC(infinity) were within the acceptance range (0.80-1.25), satisfying the bioequivalence criteria of the Thailand Food and Drug Administration Guidelines. These results indicate that Dozozin-2 is bioequivalent to Cardura and, thus, may be prescribed interchangeably.

Sildenafil citrate improves erectile function and lower urinary tract symptoms independent of baseline body mass index or LUTS severity

OBJECTIVES

To evaluate the body mass index (BMI) and lower urinary tract symptom (LUTS) severity on treatment response to sildenafil in men with erectile dysfunction (ED) and moderate to severe LUTS associated with benign prostatic hyperplasia.

METHODS

A post hoc analysis of data from a 12-week, double-blind, placebo-controlled study of sildenafil (50 mg once daily titrated to 100 mg once daily) was conducted. The BMI categories were obese (> or = 30 kg/m(2)), overweight (> or = 25 to < 30 kg/m(2)), and normal weight (< 25 kg/m(2)). ED was defined as a score of < or = 25 on the erectile function domain of the International Index of Erectile Function, and LUTS was defined by an International Prostate Symptom Score of > or = 12. The maximal urinary flow rate was determined by uroflowmetry.

RESULTS

Patients receiving sildenafil (n = 189) had a significant improvement in the erectile function domain scores of the International Index of Erectile Function (P < .0001 vs placebo, n = 180), which did not vary across BMI groups. A greater improvement in LUTS score was observed with sildenafil compared with placebo for men with severe LUTS (-8.6 vs -2.4, P < .0001) than in men with moderate LUTS (-3.6 vs -1.7, P = .06). Also, the improvement in LUTS scores was significant (P < or = .02) for men taking sildenafil independent of BMI (obese, -8.9 vs -5.4; overweight, -7.3 vs -3.2; normal weight, -7.1 vs -0.84). No difference was found among the treatment groups in the change from baseline maximal urinary flow rate across all LUTS and BMI categories (range 4.5 to -4.2 mL/s).

CONCLUSIONS

The results of our study have shown that daily dosing with sildenafil improved ED and LUTS independent of baseline LUTS severity or BMI.

A review of combination therapy in patients with benign prostatic hyperplasia

BACKGROUND

Trials of monotherapy with alpha(1)-adrenergic-receptor antagonists (alpha(1)ARAs) and 5 alpha-reductase inhibitors (5ARIs) have found that the former drug class is effective in managing benign prostatic hyperplasia (BPH)-related lower urinary tract symptoms (LUTS) and improving the maximal urinary flow rate in shortand long-term treatment, regardless of prostate size, whereas the latter drug class is effective in reducing prostate size and preventing disease progression in longer-term treatment. The differing mechanisms of action and areas of efficacy of these 2 drug classes make them promising candidates for combination therapy.

OBJECTIVE

This article reviews key trials of monotherapy and combination alpha(1)ARV5ARI therapy in the treatment and prevention of BPH-related voiding dysfunction.

METHODS

MEDLINE (1976-2006) and the Cochrane Central Register of Controlled Trials (1976-2006) were searched for relevant clinical trials and reviews using the terms benign prostatic byperplasia, lower urinary tract symptoms, LUTS, alpha-adrenergic-receptor antagonists, alpha-blockers, 5 alpha-reductase inhibitors, combination therapy, MTOPS, SMART, PREDICT, adverse events, alfuzosin, doxazosin, tamsulosin, terazosin, dutasteride, and finasteride. Abstracts from selected professional conferences also were reviewed.

RESULTS

Three previous trials of alpha(1)ARA/5ARI therapy found no therapeutic benefit for combination therapy relative to monotherapy, but their conclusions were limited to some extent by their designs, particularly the duration of treatment. Data from the Medical Therapy of Prostatic Symptoms (MTOPS) study, however, indicated a potential role for long-term use of alpha(1)ARA/5ARI therapy, particularly in patients with greater symptom severity (mean score of 17 on the American Urological Association symptom index), larger prostate volume (mean, 32 g), and higher prostate-specific antigen (PSA) levels (>1.5 ng/mL) at baseline. In the MTOPS study, combination therapy with the alpha(1)ARA doxazosin and the SARI finasteride was significantly more effective than either component alone in reducing BPH-related symptoms (P=0.006 vs doxazosin monotherapy; P<0.001 vs finasteride monotherapy) and lowering the rate of overall clinical progression (P<0.001 vs either monotherapy). In addition, there are data from a subgroup analysis of MTOPS suggesting that the presence of prostatic inflammation may indicate a greater likelihood of treatment efficacy with combination alpha(1)ARA/5ARI therapy.

CONCLUSIONS

The available data suggest that combination alpha(1)ARA/5ARI therapy is beneficial in the treatment of BPH and the associated symptoms. The greatest efficacy was evident in patients with an enlarged prostate, more severe symptoms, and higher PSA levels. There are limited data suggesting that the presence of prostatic inflammation may indicate a greater likelihood of treatment efficacy with combination therapy.

Short-term efficacy and long-term compliance/treatment failure of the alpha1 blocker naftopidil for patients with lower urinary tract symptoms suggestive of benign prostatic hyperplasia

OBJECTIVE

To evaluate treatment failure during a 4-year follow-up period after administration of naftopidil for patients with lower urinary tract symptoms (LUTS) suggestive of benign prostatic hyperplasia (BPH) in real-life clinical practice.

MATERIAL AND METHODS

A total of 247 patients with LUTS/BPH who had an International Prostate Symptom Score (IPSS) of > or =8 were enrolled in the study. Naftopidil, 50 mg/day, was given to the patients. They were followed for 4 years with periodic evaluation. Treatment failure was defined as conversion to other medical treatment or to surgery.

RESULTS

Of the 247 patients, treatment failure occurred in 42 (17.0%) during the 4-year follow-up period. The 4-year treatment failure rate was on the Kaplan-Meier curve 35.0%. Among parameters assessed at baseline, prostate volume (PV) was the only significant determinant of treatment failure: patients with a PV of > or =35 ml had a 2.1 times higher hazard of treatment failure than those with a PV of <35 ml (95% CI 1.06-4.33; p=0.03). Patients with a severe IPSS at 12 weeks after administration of naftopidil had a 3.5 times higher hazard than those having a mild/moderate IPSS (95% CI 1.34-9.26; p=0.01). After 4 years, 200 patients (81%) had stopped taking naftopidil because of adverse events, treatment failure, loss to follow-up, etc.

CONCLUSIONS

There were significant improvements in IPSS and urinary flow rate with naftopidil although it is unknown whether these improvements were significantly larger than the placebo effect as the study was non-randomized. However, only 19% of patients were known to have continued with the same medication for 4 years in real-life clinical practice. Patients who have a large prostate at baseline and a severe IPSS at 12 weeks after treatment are more likely to have treatment failure, although a prospective study is needed to confirm this.

Clinical spectrum of the osmotic-controlled release oral delivery system (OROS), an advanced oral delivery form

BACKGROUND

The osmotic-controlled release oral delivery system, OROS, is an advanced drug delivery technology that uses osmotic pressure as the driving force to deliver pharmacotherapy, usually once-daily, in several therapeutic areas.

OBJECTIVE

The purpose of this review is to discuss the evolution of OROS technology and examine the many therapeutic areas where OROS products are being used.

METHODS

A search of Medline and EMBASE were performed using the keywords 'OROS' and 'osmotic delivery' for the period January 1990 to June 2005. Data were also obtained from the manufacturers' websites and associated publications.

RESULTS

OROS technology has evolved over the last 30 years, resulting in four systems: the elementary osmotic pump; the two-layer osmotic push-pull tablet; the advanced longitudinally compressed tablet multilayer formulation; and, the L-OROS system. OROS technology is employed for drug delivery in many therapeutic areas including: cardiovascular medicine, endocrinology, urology, and central nervous system (CNS) therapeutics. Two calcium channel blockers utilizing OROS technology for the treatment of hypertension are nifedipine and verapamil. Glipizide extended-release is used for the treatment of type 2 diabetes. Doxazosin is used for the treatment of benign prostatic hyperplasia, and oxybutynin for overactive bladder. Most recent developments are with drugs that affect the CNS, including the use of methylphenidate for treatment of attention deficit hyperactivity disorder, paliperidone extended-release and OROS hydromorphone, which are under clinical development for schizophrenia and chronic pain, respectively.

CONCLUSIONS

Drug delivery using the various OROS products can result in an improved safety profile, stable drug concentrations, uniform drug effects, and reduced dosing frequency. OROS technology has also enabled the use of an effective starting dose, without the need for dose titration, which allows the achievement of symptom control much earlier than that observed with immediate-release preparations. Such attributes can enhance patient compliance and convenience, thereby ensuring efficacy and improving patient outcomes.

Validation and pharmacokinetic application of a method for determination of doxazosin in human plasma by high-performance liquid chromatography

A simple high-performance liquid chromatographic method for the determination of doxazosin in human plasma was developed and validated. Prazosin was used as internal standard. After extraction twice with ethyl acetate, chromatographic separation of doxazosin in human plasma was carried out using a reversed-phase Apollo C18 column (250 x 4.6 mm, 5 microm) with mobile phase of methanol-acetonitrile-0.04 m disodium hydrogen orthophosphate (22:22:56, v/v/v) adjusted to pH 4.9 with 0.9 m phosphoric acid and quantified by fluorescence detection operated with an excitation wavelength of 246 nm and an emission wavelength of 389 nm. The lower limit of quantification (LLOQ) of this assay was 1 ng/mL using 500 microL human plasma. Linearity was established over the range 1-25 ng/mL (r2 > 0.9994). The intra- and inter-day accuracy ranged from 90.5 to 104.4% and the coefficient of variation were not more than 8.6% for both intra- and inter-day precision, over the range of the calibration curve. The absolute recoveries of doxazosin and prazosin from human plasma were more than 91%. Doxazosin demonstrated acceptable short-term, long-term and freeze-thaw stability in human plasma. The assay has been successfully applied to plasma sample ana-lysis for pharmacokinetic study.

Effects of ??1-Adrenoceptor Antagonists on Male Sexual Function

alpha(1)-Adrenoceptor antagonists such as alfuzosin, doxazosin, tamsulosin and terazosin are first-line agents for the treatment of lower urinary tract symptoms suggestive of benign prostatic hyperplasia (BPH), but are only second-line agents (doxazosin and terazosin only) for the treatment of arterial hypertension. Sexual function is complex and includes multiple domains such as sexual desire (libido), erectile function and ejaculatory function. Erectile and ejaculatory functions are frequently reduced in patients with BPH and can impact on their quality of life. Therefore, the treatment of BPH should aim to maintain or even restore sexual function.alpha(1)-Adrenoceptor antagonists lack major effects on sexual desire in placebo-controlled studies. Reports on erectile function are inconsistent, with both beneficial and adverse effects being reported, but impotence can occur in some patients without clear differences between drugs. Ejaculatory dysfunction during treatment may represent (relative) an ejaculation. It occurs more frequently with tamsulosin than with other drugs of this class, but the differences are not big enough to be consistently detectable in directly comparative studies. We propose that such differences between drugs should be weighed against differences in cardiovascular tolerability when choosing the optimal treatment for each patient.

Combined use of alpha-adrenergic and muscarinic antagonists for the treatment of voiding dysfunction

PURPOSE

We provide an overview of the medical literature supporting the combined use of muscarinic and alpha-adrenergic antagonist therapy for the treatment of voiding dysfunction.

MATERIALS AND METHODS

The MEDLINE database (1966 to 2004) of the United States National Library of Medicine was searched for pertinent studies.

RESULTS

Although the mechanism of action of alpha-adrenergic antagonist therapy for voiding dysfunction has traditionally been assumed to be relaxation of the periurethral, prostatic and bladder neck smooth muscle, substantial evidence supports action at extraprostatic sites involved in micturition, including the bladder dome smooth muscle, peripheral ganglia, spinal cord and brain. Likewise the mechanism of action of anticholinergic therapy has been traditionally assumed to be inhibition of the M3 muscarinic receptor subtypes that mediate normal bladder contractions. However, M2 receptor mediates hypertrophied bladder contractions and there is evidence for an M2 component to the suprasacral control of voiding.

CONCLUSIONS

Based on the physiology of alpha-adrenergic and muscarinic receptors the inhibition of each one would be expected to be more beneficial than that of either alone because they would work on 2 components of detrusor function. Patients who would likely benefit from this combination therapy are men with lower urinary tract symptoms, women with urgency/frequency syndrome (overactive bladder), patients with uninhibited bladder contractions due to neurogenic bladder, and patients with pelvic pain and voiding symptoms, ie interstitial cystitis and chronic prostatitis/chronic pelvic pain syndrome.

Treatment of benign prostatic hyperplasia in hypertensive men

As the proportion of the US population over the age of 65 continues to rise, it is likely that the number of individuals with concomitant benign prostatic hyperplasia and hypertension will also increase. To reduce morbidity and mortality, it is important to treat patients with hypertension optimally. Evidence from outcome trials suggests that alpha1 blockers should not be used as first-line antihypertensive therapy. Although some clinicians previously recommended alpha1 blocker monotherapy for patients with both hypertension and benign prostatic hyperplasia, the most recent American Urologic Association and Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure guidelines recommend independent treatment with the most appropriate pharmacologic agents for each condition. When treating patients with benign prostatic hyperplasia, clinicians should be aware of the potential impacts that alpha1 blockers may have on blood pressure and potential adverse events in patients who are normotensive as well as in patients with treated hypertension.

The Vasodilatory Effect of Alfuzosin and Tamsulosin in Passive Orthostasis: A Randomised, Double-Blind, Placebo-Controlled Study

OBJECTIVE

To compare in details the effects of urologically used alpha(1)-blockers alfuzosin and tamsulosin on the cardiovascular responses to passive orthostasis.

METHODS

The responses to passive orthostasis (tilt provocation at 60 degrees for 8 min) were measured in normotensive healthy volunteers with finger blood pressure method and whole-body impedance cardiography prior to the administration of the drugs as well as three days after the beginning of the randomised, double-blind medications. The parallel treatments were standard clinically used doses of alpha(1)-blockers alfuzosin (5 mg twice daily, n=10), tamsulosin (0.4 mg once daily, n=10), or placebo (n=11).

RESULTS

When measured prior to the head-up tilt test in supine position, neither alfuzosin nor tamsulosin significantly changed any of the cardiovascular variables. During the passive orthostasis, however, both tamsulosin and alfuzosin reduced systemic vascular resistance index compared to pre-drug responses (-540 and -462 dyns/cm(5)m(2), respectively, p<0.05). Both drugs also augmented orthostatic responses of heart rate (11 and 9 bpm, respectively, p<0.05) and cardiac index (0.50 and 0.40 l/min/m(2), respectively, p<0.05) but not those of stroke index when compared to the responses during placebo or before the administration of the drugs. The alfuzosin and tamsulosin groups did not significantly differ from each other in terms of any parameter.

CONCLUSIONS

Both alfuzosin and tamsulosin have clear cardiovascular effects, which are most strikingly evident in the influences on systemic vascular resistance and cardiac output.

No risk of drug-associated liver injury with?1-adrenoreceptor blocking agents in men with BPH: results from an observational study using the GPRD

PURPOSE

To compare the risk of liver injury in men treated with alpha1-blockers against that in a similar non-exposed population.

METHODS

Using a study population registered on the UK General Practice Research Database (GPRD) we performed (a) a retrospective cohort analysis amongst men with lower urinary tract symptoms (LUTS) indicative of benign prostatic hypertrophy (BPH) comparing the incidence of liver injury in men exposed to alpha1-blockers with the incidence in those not exposed, and (b) two nested case-control studies looking at risk factors associated with the development of liver injury compared with age- or practice-matched controls.

RESULTS

Amongst 45,851 men with LUTS/BPH, 9666 were exposed to an alpha1-blocker and 154 were identified with drug-induced/idiopathic liver injury. The crude incidence of liver injury in men with LUTS/BPH exposed to an alpha1-blocker was not statistically significantly different from that in the unexposed population (13.9 vs. 11.0 cases per 10,000 exposed years: incidence rate ratio (IRR) 1.28 [95% confidence interval (CI): 0.64, 2.31]). In the case-control analyses, the adjusted odds ratio (OR) of liver injury associated with exposure to alpha1-blockers compared with no use was not statistically significant (age-matched OR 0.92 [95%CI: 0.43, 1.97]; practice-matched OR 0.98 [95%CI: 0.45, 2.16]). Our analyses confirmed an association between liver injury and alcohol consumption as well as exposure to various classes of drugs known to be potentially hepatotoxic.

CONCLUSIONS

This study could not offer any evidence to support an association between exposure to alpha1-blockers and liver injury in men with LUTS/BPH.

INTERACTION BETWEEN THE PHOSPHODIESTERASE 5 INHIBITOR, TADALAFIL AND 2 α-BLOCKERS, DOXAZOSIN AND TAMSULOSIN IN HEALTHY NORMOTENSIVE MEN

PURPOSE

Tadalafil, a phosphodiesterase type 5 inhibitor, is effective therapy for erectile dysfunction (ED). Men with ED have a high incidence of comorbid conditions including cardiovascular disease, diabetes mellitus and benign prostatic hyperplasia. Although phosphodiesterase type 5 inhibitors are safe when administered with most medications, sildenafil given with doxazosin and vardenafil given with terazosin evoke orthostatic hypotension in some patients. We examined the hemodynamic interactions of tadalafil with the alpha-blockers doxazosin and tamsulosin.

MATERIALS AND METHODS

In separate double-blind, placebo controlled, randomized crossover studies (18 patients in each study) we evaluated the hemodynamic effects of doxazosin 8 mg with tadalafil 20 mg, and tamsulosin 0.4 mg with tadalafil 10 and 20 mg. Blood pressure (BP) and heart rate were recorded before dosing and for 24 hours after dosing.

RESULTS

Tadalafil 20 mg augmented the hypotensive effect of doxazosin by producing a mean maximal decrease in standing systolic BP (SBP) that was significantly greater than placebo (a mean difference of 9.8 mm Hg). Analysis of BP outliers showed that the number of subjects with a standing SBP of less than 85 mm Hg was greater after doxazosin plus tadalafil (28%) versus doxazosin plus placebo (6%). In subjects on tamsulosin, tadalafil 10 and 20 mg produced mean maximal decreases in standing SBP that were similar to placebo (mean difference of 1.7 and 2.3 mm Hg, respectively). No subject taking tamsulosin had a decrease in standing SBP less than 85 mm Hg.

CONCLUSIONS

Tadalafil augmented the hypotensive effects of doxazosin but had little hemodynamic interaction with tamsulosin. In patients taking tadalafil for ED, tamsulosin 0.4 mg may be given for the treatment of benign prostatic hyperplasia.

Comparative efficacy of two alpha-adrenoreceptor antagonists, doxazosin and alfuzosin, in patients with lower urinary tract symptoms from benign prostatic enlargement

OBJECTIVES

To compare doxazosin and alfuzosin in patients with moderate to severe lower urinary tract symptoms (LUTS) suggestive of bladder outlet obstruction.

PATIENTS AND METHODS

In all, 210 men with LUTS were randomized to receive doxazosin 1-8 mg once daily or alfuzosin 5-10 mg divided in two or three daily doses in a 14-week, multicentre, double-blind, baseline-controlled, dose-titration study. The International Prostate Symptom Score (IPSS) and maximum urinary flow rate were used to assess the efficacy of the treatment.

RESULTS

At study completion, the mean dose of doxazosin was 6.1 mg/day and alfuzosin 8.8 mg/day. The least squares mean (se) change from baseline in total IPSS was -9.23 (0.6) for doxazosin and -7.45 (0.6) (both P < 0.001) for alfuzosin. The respective mean change from baseline in irritative symptoms was -3.5 (0.2) and -2.8 (0.3) (both P < 0.001). The differences between the treatment groups were statistically significant in favour of doxazosin (total IPSS, P = 0.036; irritative symptoms, P = 0.049). The improvement between groups was also significantly different for postvoid residual urine volume, at -29.19 (8.6) and + 9.59 (8.9) mL for doxazosin and alfuzosin, respectively (P = 0.002). Improvements in mean and maximum urinary flow rates were similar for both treatments, at + 1.5 and + 1.2, and + 2.8 and + 2.5 mL/s, respectively. Doxazosin and alfuzosin were both well tolerated, with most all-cause adverse events reported as mild or moderate.

CONCLUSIONS

The mean doses of doxazosin and alfuzosin used in this study were not equipotent. Doxazosin 6.1 mg/day produced significantly greater improvements than alfuzosin 8.8 mg/day in total and irritative urinary symptom scores and postvoid residual urine volume in men with moderate to severe LUTS. Changes in maximum and mean flow rates were comparable. Doxazosin and alfuzosin were both well tolerated.

Lower urinary tract symptoms, pain and quality of life assessment in chronic non-bacterial prostatitis patients treated with alpha-blocking agent doxazosin; versus placebo

The efficacy of doxazosin monotherapy in chronic non-bacterial prostatitis was investigated in terms of urinary symptom, pain and quality of life assessment versus placebo. A total of 60 men with chronic non-bacterial prostatitis were randomised to daily supplement of 4 mg doxazosin or a placebo, for 3 months. International Prostate Symptom Score (IPSS) questionnaire was self administered at the entry and at 3 months after the cessation of the treatment. In addition, patients were asked to complete 2-item questionnaire on pain related symptoms of chronic prostatitis. Quality of life was assessed with a single item included in IPSS. Three months after cessation of the treatment there was a significant difference between the overall mean IPSS, pain and quality of life scores of the two groups in favour of alpha-blocking agent use (p = 0.001, p < 0.001 and p < 0.001, respectively). In patients undergone doxazosin treatment; symptom, pain and quality of life status revealed 32.94 +/- 5.27%, 36.57 +/- 5.67% and 36.78 +/- 4.75% overall improvement, respectively. IPSS appeared to be a valuable tool in assessing treatment outcome of chronic non-bacterial prostatitis.

Tratamiento con doxazosina en 3.347 pacientes con síntomas del tracto urinario inferior. efecto sobre su función sexual. estudio impros

OBJECTIVES

An open, non-comparative, multicenter study was performed to ascertain the prevalence in Spain of erectile dysfunction (ED) associated to benign prostatic hypertrophy (BPH), with moderate to severe urinary symptoms, and to confirm the improvement or disappearance of ED in response to treatment with 4 mg/day of Doxazosin.

METHODS

Out of the 3901 patients recruited 3545 took the medication and 3347 completed all the protocol visits. BPH patients were considered to have some degree of erectile dysfunction when they reported a difficulty for obtaining and/or maintaining an erection in the four weeks prior to their inclusion in the study (questions 3 and 4 of the International Index of Erectile Function). All the patients were treated with Doxazosin at increasing doses: from 1 mg/day up to 4 mg/day thereafter until 6 months of medication were completed.

RESULTS

The mean number of patients showing erectile dysfunction was 69.1%, ranging from 48.3% in the 40-49 years age group to 76.3% in the group aged from 60 to 69 years. In most Spanish regions, the prevalence of ED ranged from 76.9% in Cantabria to 67.2% in Aragon. The mean number of patients in whom erectile dysfunction disappeared after treatment, with a 95% confidence interval, was 4.5%, ranging from 17.5% in the 40-49 age group to 1.1% in the over 70s.

CONCLUSIONS

ED is a symptom very often associated to BPH, even in relatively young men. Doxazosin appears to have a beneficial effect in ED improvement, particularly in the younger patients.

Could self-management challenge pharmacotherapy as a long-term treatment for uncomplicated lower urinary tract symptoms?

PURPOSE OF REVIEW

This review highlights the lifestyle and behavioural management strategies (self-management) available to men with lower urinary tract symptoms.

RECENT FINDINGS

Pharmacotherapy has evolved considerably over the last decade and now most men with lower urinary tract symptoms are treated at some point with either single or combined therapy. However, recent studies reporting the longer term usage of pharmacotherapy have shown significantly high rates of discontinuation due to patient compliance, treatment ineffectiveness, side effects and patient choice. Not all these men will require or desire surgery. For those with bothersome symptoms self-management may be an effective strategy. Self-management interventions include education, reassurance, fluid management, caffeine avoidance, rescheduling concurrent medications and bladder retraining. As in other chronic disease areas such as diabetes and arthritis for which self-management is well established, lifestyle and behavioural interventions for men with lower urinary tract symptoms aim to allow the patient some day-to-day control over their symptoms. These interventions have been shown to be in wide use in the UK without good quality supporting evidence, suggesting that they are thought to be safe and effective.

SUMMARY

Self-management (lifestyle and behavioural) interventions provide men with some control over their symptoms, their role as either a primary treatment strategy or to augment pharmacotherapy has yet to be defined.

Long-term safety and efficacy of tamsulosin for the treatment of lower urinary tract symptoms associated with benign prostatic hyperplasia

PURPOSE

We evaluated the long-term (up to 6 years) safety and efficacy of the selective alpha 1A-adrenoceptor antagonist tamsulosin in patients with lower urinary tract symptoms associated with benign prostatic hyperplasia.

MATERIALS AND METHODS

A total of 609 patients were enrolled in a 4-year multicenter open label extension study. Subjects entered the study after completion of a 1-year open label trial that included patients who previously completed up to 57 weeks of double-blind, placebo controlled studies. Maintenance doses (0.4 or 2 x 0.4 mg daily) established in the 1-year study were continued. Efficacy and safety were assessed every 3 months. Primary efficacy evaluations were changes from baseline maximum urine flow rate and total American Urological Association symptom index, and the responder rates for those 2 end points. Secondary end points were changes in American Urological Association subset scores, Boyarsky symptom scores, average urine flow rate, post-void residual urine volume, quality of life index and investigator global assessment.

RESULTS

Of the 609 patients who entered the 4-year extension study 159 had a 2-year or greater prior experience with tamsulosin, yielding a potential 6-year experience on the medication. Of this 159 patient subset 109 completed the whole 6 years. Initial rapid improvements from baseline in primary and secondary end points were maintained each year throughout the duration of the study. Tamsulosin was well tolerated, confirming the safety profile demonstrated in earlier studies. Orthostatic hypotension was observed in 1.3% of the patients.

CONCLUSIONS

This study demonstrates the sustained efficacy, safety and excellent long-term tolerability of tamsulosin for up to 6 years in patients with lower urinary tract symptoms associated with benign prostatic hyperplasia.

Identification of baseline clinical factors which predict medical treatment failure of benign prostatic hyperplasia: an observational cohort study

OBJECTIVE

The aim of this study was to identify the clinical baseline factors that affect the long-term treatment failure of benign prostatic hyperplasia (BPH).

METHODS

437 men over 50 years of age with BPH were enrolled for this analysis. Patients were allocated to a medication and a surgical treatment (following medication) group. We initially examined the International Prostatic Symptom Score (IPSS), uroflow rate, prostate volume, postvoid residual volume, and the serum prostate specific antigen level as clinical baseline factors and analyzed differences between the two groups.

RESULTS

337 patients (77.1%) were given maintenance medical treatment during follow-up, and 100 patients (22.9%) had surgical treatment following medication. Statistically significant differences were found in IPSS and prostate volume between the surgical and medication groups (IPSS: 22.6+/-6.4 vs. 18.7+/-5.8, prostate volume (cm(3)): 36.3+/-14.4 vs. 30.1+/-11.0, respectively). According to the ROC curve-based prediction of the failure for medical therapy, the best cutoff values of IPSS and prostate volume were 21 (area under ROC curve: 0.67) and 32cm(3) (area under ROC curve: 0.65), respectively.

CONCLUSIONS

The results show that BPH patients with more severe IPSS and larger prostate volume have a higher risk of medical treatment failure, and suggest that the IPSS and prostate volume may be useful predictors of medical treatment maintenance.

Effect of doxazosin GITS on blood pressure in hypertensive and normotensive patients: a review of hypertension and BPH studies

Doxazosin is an effective treatment for patients with hypertension, benign prostatic hyperplasia (BPH) and the two comorbidly. In its standard formulation, doxazosin requires a multistep titration regimen to minimize a possible first-dose effect. A new extended-release gastrointestinal therapeutic system (GITS) formulation of doxazosin was developed to improve the pharmacokinetic profile of the parent compound and to reduce or eliminate the need for dose titration and the potential risk of overdosing. This review presents an analysis of the effect of doxazosin GITS monotherapy on blood pressure (BP) and tolerability, as evaluated in four clinical trials, two conducted in patients with stage 1 to stage 2 hypertension and two in patients with BPH with different levels of BP. Doxazosin GITS was as effective as doxazosin standard and more effective than placebo was in reducing and controlling BP in patients with hypertension. Among normotensive patients with BPH, no clinically significant effect on BP was observed and no episodes of syncope were recorded. Doxazosin GITS was generally better tolerated than doxazosin standard, based on the proportion of patients with adverse events and those withdrawing due to adverse events. Moreover, the GITS formulation eliminated the need for titration in most patients. Doxazosin GITS is an effective and well-tolerated treatment in patients with hypertension and/or BPH and without heart failure or clinical coronary heart disease and has advantages over doxazosin standard in terms of a simpler dosing regimen and improved tolerability.

Long-term treatment with finasteride in men with symptomatic benign prostatic hyperplasia: 10-year follow-up

OBJECTIVES

To evaluate the safety and efficacy of finasteride 5 mg during a 10-year period in men with enlarged prostates from a single center who participated in the double-blind and extension phases of the multicenter, Phase III, North American benign prostatic hyperplasia (BPH) trial. It is important that the long-term safety and efficacy of drugs intended for chronic administration in men with BPH be well understood.

METHODS

The Phase III North American BPH trial involved a 1-year, placebo-controlled, double-blind study, followed by a 5-year open extension with finasteride 5 mg/day. The trial enrolled men with symptomatic BPH, an enlarged prostate on digital rectal examination, and no evidence of prostate cancer. Of the 46 patients originally enrolled from our institution, 43 were randomized to receive finasteride or placebo, of whom 41 (95%) completed the double-blind study and entered the 5-year extension. Thirty (73%) of these 41 patients completed the 5-year extension. Patients continued to be followed up by their physicians for an additional 5 years, for a total follow-up of at least 10 years.

RESULTS

Twenty-four (56%) of the original 43 patients randomized to finasteride or placebo were judged as successfully treated during the 10-year finasteride follow-up (17 patients taking finasteride alone at 10 years and 7 patients who were taking finasteride alone when they discontinued during the 10-year follow-up for reasons not related to finasteride treatment). Altogether, 22 (51%) of the original 43 randomized patients continued finasteride treatment at 10 years (17 taking finasteride alone, 4 taking finasteride plus an alpha-blocker, and 1 taking finasteride for treatment of hematuria). Finasteride was well tolerated, with no new adverse experiences occurring with increasing duration of exposure to the drug.

CONCLUSIONS

This long-term follow-up study has demonstrated that appropriately selected patients with symptomatic BPH and enlarged prostates are likely to have a long-term response to taking finasteride 5 mg daily.

Efficacy and tolerability of doxazosin and finasteride, alone or in combination, in treatment of symptomatic benign prostatic hyperplasia: the Prospective European Doxazosin and Combination Therapy (PREDICT) trial

OBJECTIVES

To evaluate the efficacy and tolerability of the selective alpha(1)-adrenergic antagonist doxazosin and the 5-alpha-reductase inhibitor finasteride, alone and in combination, for the symptomatic treatment of benign prostatic hyperplasia.

METHODS

In a prospective, double-blind, placebo-controlled trial, 1095 men aged 50 to 80 years were randomized to treatment for 52 weeks with doxazosin, finasteride, the combination of doxazosin and finasteride, or placebo. The dose of finasteride (or its matched placebo) was 5 mg/day. Doxazosin (or its matched placebo) was initiated at 1 mg/day, and titrated up to a maximum of 8 mg/day over approximately 10 weeks according to the response of the maximal urinary flow rate (Qmax) and International Prostate Symptom Score (IPSS). The IPSS and Qmax were assessed at baseline and at weeks 10, 14, 26, 39, and 52 or at the endpoint.

RESULTS

An intent-to-treat analysis of 1007 men showed doxazosin and doxazosin plus finasteride combination therapy produced statistically significant improvements in total IPSS and Qmax compared with placebo and finasteride alone (P <0.05). Finasteride alone was not significantly different statistically from placebo with respect to total IPSS and Qmax. All treatments were generally well tolerated.

CONCLUSIONS

Doxazosin was effective in improving urinary symptoms and urinary flow rate in men with benign prostatic hyperplasia, and was more effective than finasteride alone or placebo. The addition of finasteride did not provide further benefit to that achieved with doxazosin alone.

Current concepts in the pharmacotherapy of benign prostatic hyperplasia

Benign prostatic hyperplasia is a major men's health issue, with approximately 80% of all men developing this condition within their lifetime. A variety of oral treatments is available, including alpha-adrenoceptor antagonists (alpha-blockers), 5alpha reductase inhibitors, aromatase inhibitors and phytotherapy. A large number of alpha-blockers can be administered, but no single agent has demonstrated a clear superiority over the other drugs. 5alpha Reductase inhibitors have demonstrated similar efficacy in larger volume prostates but most evidence suggests that there is no benefit in combining them with alpha-blockers. The use of phytotherapy is not entirely novel but requires further long-term evaluation before it can be endorsed for clinical use in benign prostatic hyperplasia.

Doxazosin and congestive heart failure

Doxazosin remains a commonly used antihypertensive medication, although its use has been tainted by recent findings from the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT). ALLHAT was a large, simple trial, designed in a fashion to closely mimic clinical practice as it occurs in high-risk hypertensive patients aged 55 years or older. Its goals were to determine whether the incidence of the primary outcome--a composite of fatal coronary heart disease and nonfatal myocardial infarction--differed between treatment with a diuretic (chlorthalidone) (12.5-25.0 mg/day) and treatment with each of three other types of antihypertensive drugs-a calcium-channel blocker (amlodipine), an angiotensin-converting enzyme inhibitor (lisinopril), and a peripheral alpha-adrenergic blocker (doxazosin) (2-8 mg/day). Doxazosin was recently withdrawn from this trial after an interim analysis showed the secondary end point of combined cardiovascular disease to be 25% greater in patients on doxazosin than in those assigned to treatment with chlorthalidone. This finding was largely driven by congestive heart failure. The practicing clinician should not abandon doxazosin completely because of the ALLHAT findings, although these findings are indisputably important. These results represent an interim analysis and their application to clinical practice needs to occur carefully. A valued member of our therapeutic armamentarium need not be laid entirely to rest; rather, doxazosin should now be viewed as a secondary or tertiary antihypertensive therapy pending a more complete review of the ALLHAT data.

Long-term risk of re-treatment of patients using alpha-blockers for lower urinary tract symptoms

PURPOSE

The efficacy of alpha-adrenoceptor blockers for the treatment of lower urinary tract symptoms has been proven in numerous studies. However, little is known about the efficacy of the longer term. We investigated the long-term risk of re-treatment in patients using alpha-adrenoceptor blockers for lower urinary tract symptoms and the parameters that influence this risk.

MATERIALS AND METHODS

We reviewed the files of 316 patients with lower urinary tract symptoms treated at our department with the alpha-blockers terazosin, alfuzosin or tamsulosin. Using followup data up to 3 years, we calculated re-treatment percentages in each treatment group. Using extended followup of 5 years, we calculated the predictive value of various baseline characteristics for re-treatment.

RESULTS

The re-treatment rates were 27% for tamsulosin, 37% for alfuzosin and 49% for terazosin. The re-treatment rates of patients with mild, moderate and severe lower urinary tract symptoms were 27%, 33% and 70%, respectively. Patients with a maximum urine flow of less or more than 10 ml. per second had a re-treatment rate of 58% and 47%, respectively. Patients with a prostate volume of less or more than 40 ml. had a re-treatment rate of 48% and 72%, respectively. Patients who were urodynamically unobstructed versus obstructed patients had a re-treatment rate of 44% and 59%, respectively.

CONCLUSIONS

Patients given alpha-blockers for lower urinary tract symptoms have a high risk of re-treatment. Tamsulosin has a markedly lower re-treatment percentage than alfuzosin and terazosin. Severe symptoms, poor urine flow, an enlarged prostate and urodynamically proven bladder outlet obstruction increase the risk of treatment failure. Preselection of the most suitable candidates for alpha-blockade may reduce this risk.

Benign prostatic hypertrophy which nonoperative strategies are best?

Benign prostatic hypertrophy is one of the common complaints of older men who visit their primary care physicians. Nonoperative therapy, such as drug therapy or lifestyle modification, is aimed primarily at reducing bothersome lower urinary tract symptoms and preventing serious morbidity such as urinary retention and renal function impairment. As more men reach advanced age, it becomes crucial for the primary care physician to be aware of the epidemiology, pathophysiology, natural history, clinical presentation, and therapeutic modalities available for the treatment of clinically significant cases.

Long-term safety and efficacy of a once-daily formulation of alfuzosin 10 mg in patients with symptomatic benign prostatic hyperplasia: open-label extension study

OBJECTIVES

To evaluate the long-term safety and efficacy of a new, once-daily (o.d.) prolonged-release formulation of the clinically uroselective alpha1-blocker, alfuzosin, in patients with symptomatic benign prostatic hyperplasia (BPH).

METHODS

This is a 9-month open-label extension of a 3-month double-blind, placebo-controlled evaluation of alfuzosin 10 mg o.d. and standard alfuzosin 2.5 mg, three times daily (t.i.d.), administered without dose titration in both cases. A total of 311 patients continued in the extension phase and all received alfuzosin 10 mg o.d. Efficacy was evaluated in all patients enrolled in the extension phase (n = 311). Safety was assessed in all patients exposed to alfuzosin, whether in the double-blind or extension phase (n = 360).

RESULTS

Mean international prostate symptom score (IPSS) improved significantly, from 17.1 to 9.3 (P < 0.0001), and mean peak flow rate (PFR) (assessed at through plasma levels) increased significantly, from 9.1 to 11.3 ml/s (P < 0.0001), between baseline (i.e. beginning of the double-blind phase) and the endpoint of the extension phase. Quality of life (QOL) index also improved significantly, from 3.3 to 2.1 (P < 0.0001). Alfuzosin was well tolerated, with only 16 of 360 patients (4.4%) reporting adverse events potentially related to alpha-blockade (mainly dizziness). Ejaculation disorders were infrequent (0.6%) and did not show a relationship to treatment. The incidence of asymptomatic orthostatic hypotension was low (2.8%), and no age effect was identified.

CONCLUSIONS

Alfuzosin 10 mg o.d. provides effective relief from BPH, and clinical benefits are maintained up to 12 months. This study also demonstrates the satisfactory long-term safety of this formulation, and its safe use even in at-risk populations.

Drug or symptom-induced depression in men treated with alpha 1-blockers for benign prostatic hyperplasia? A nested case-control study

PURPOSE

Regulatory authorities have raised concern that alpha 1-blockers, prescribed predominantly for benign prostatic hyperplasia (BPH), may be associated with an increased risk of depression. The aim was to assess the risk of depression with alpha 1-blockers independently of that associated with symptoms being treated and concurrent illness.

METHODS

Using a study population registered on the UK General Practice Research Database, and taking a prescription for an antidepressant as a proxy for clinical depression, we performed: (a) cohort analyses comparing the incidence of depression in current users of alpha 1-blockers versus non-users, and in men with BPH versus those without. (b) A nested case-control analysis looking at the association between depression and alpha 1-blocker exposure, accounting for the presence of BPH and other illness.

RESULTS

In the cohort analyses, risk of depression was significantly higher in men with BPH compared to those without (IRR 2.17, 2.12-2.22), but was not significantly different for men exposed to alpha 1-blockers versus those unexposed when adjusted for the presence of BPH. Cases of depression were more likely to have pre-existing BPH (crude OR 2.09, 2.02-2.15) than controls. After adjusting for concurrent illness (using number of GP visits as a proxy) and the presence of BPH (adjusted OR 1.38, 1.33-1.43), there was no association with depression for exposure to any alpha 1-blocker (adjusted OR 1.03, 0.90-1.18).

CONCLUSIONS

This study did not suggest that the prescribing of alpha 1-blockers increases the risk of being depressed. The association highlighted by spontaneous reporting systems appears to be explained by confounding by concurrent disease.