Overview of alpha-blocker therapy for benign prostatic hyperplasia

Sulfadiazine Masquerading as a Natural Product from Scilla madeirensis (Scilloideae)

The structure of 2,4-(4'-aminobenzenamine)pyrimidine (1), a pyrimidine alkaloid previously isolated from the bulbs of Scilla madeirensis (Asparagaceae, synonym Autonoë madeirensis), has been revised. These conclusions were met via comparison of reported NMR and EIMS data with those obtained from synthetic standards. The corrected structure is the antibiotic sulfadiazine (2), which has likely been isolated as a contaminant from the site of collection. The reported bioactivity of 1 as an α1-adrenoceptor antagonist should instead be ascribed to sulfadiazine. Our findings appear to show another example of an anthropogenic contaminant being identified as a natural product and emphasize the importance of considering the biosynthetic origins of isolated compounds within a phylogenetic context.

Effects of alpha1-adrenoceptor antagonist (tamsulosin) on incident of ejaculation and semen quality in the goat

Male temporary contraception is occasionally required in some animals. Alpha1-adrenoceptor antagonist (tamsulosin) can cause ejaculation disorder. Two sets of Latin square were applied to six male goats to received either normal saline, dimethylsulphoxide or tamsulosin (179.8 nmol kg(-1) ) at 1-week interval. Semen collection and libido scoring were undertaken at 3, 6 and 24 h post-injection. For ejaculated semen, its quality was evaluated. Physiological measurements including body temperature, respiration and heart rates were measured before injection and at 30 min before semen collection. The results showed that libido score and physiological changes were not affected by treatments and time periods. Anejaculation was observed in 11 (91.7%), 5 (41.7%) and 1 (8.3%) males at 3, 6 and 24 h post-tamsulosin injection respectively. The incidence returned to normal when compared with control groups at 24 h. The percentages of motile and live spermatozoa at 6 h post-tamsulosin injection were significantly lower (P < 0.05) than that of normal saline group. At 24 h post-injection, there were no significant differences of all semen parameters among treatments. This study demonstrated that tamsulosin had temporary effects on ejaculation and semen quality without reducing sex desire and physiological functions in male goats.

Effects of tadalafil once daily on maximum urinary flow rate in men with lower urinary tract symptoms suggestive of benign prostatic hyperplasia

PURPOSE

Tadalafil significantly improves lower urinary tract symptoms suggestive of benign prostatic hyperplasia. We post hoc characterized changes in the maximum urinary flow rate using integrated data from 4 international, placebo controlled studies of tadalafil once daily for lower urinary tract symptoms suggestive of benign prostatic hyperplasia.

MATERIALS AND METHODS

After a 4-week placebo lead-in period 1,500 men were randomized to tadalafil 5 mg or placebo for 12 weeks. Data were analyzed using ANCOVA. Maximum urinary flow rate values were rank transformed for analysis.

RESULTS

Baseline maximum urinary flow rate data were available on 1,371 men with a mean age of 63.1 years and end point data were available on 1,197. Tadalafil 5 mg significantly increased maximum urinary flow vs placebo (median 1.1 vs 0.4 ml per second, p = 0.003). At a baseline voided volume of 125 to less than 250 ml the median change in the maximum urinary flow rate was 0.9 and 1.2 ml per second (p = 0.142) in 731 patients, at a baseline of 250 to 450 ml the change was -0.3 and 0.7 ml per second (p = 0.011) in 428, and at a baseline of greater than 450 ml the change was -0.2 and 2.0 ml per second (p = 0.186) in 38 for placebo and tadalafil, respectively. The difference was 0.3, 1.0 and 2.2 ml per second, respectively. At a baseline maximum urinary flow rate of greater than 15 ml per second in 128 patients the median flow rate change was -2.1 and -0.8 ml per second (p = 0.246), at a maximum of 10 to 15 ml per second in 522 the change was 0.2 and 0.8 ml per second (p = 0.044), and at a maximum of less than 10 ml per second in 547 the change was 1.2 and 1.8 ml per second (p = 0.189) for placebo and tadalafil, respectively. Tadalafil improved I-PSS (International Prostate Symptom Score) voiding subscores significantly vs placebo across all baseline maximum urinary flow subgroups (each p <0.001).

CONCLUSIONS

This integrated analysis revealed a small but statistically significant median maximum urinary flow rate improvement for tadalafil vs placebo. The numerical difference in the maximum urinary flow change from baseline between tadalafil and placebo increased with increased voided volume.

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.

In Vitro-In Vivo Correlation Evaluation of Generic Alfuzosin Modified Release Tablets

Alfuzosin, a selective alpha-1a antagonistis is the most recently approved AARAS, with limited cardiac toxicity and exclusively used for lower urinary tract syndromes (LUTS). In order to reduce pill burden and better patient compliance modified release (MR) formulations have been developed. Alfuzosin MR tablet was developed by the use of hot-melt granulation techniques using mono- and diglycerides as rate controlling membranes to minimize health care cost and uses of costly excipients. The other purpose of the study was to evaluate in vitro-in vivo performance of the scale up batch in healthy human subjects for commercialization. The blend uniformity (mean ± RSD%), assay, cumulative percent dissolution at 24 h, hardness, and friability of the biobatch were 100.2 ± 0.05%, 100.43 ± 0.023%, 93.98%, 4.5 kg, 5 min, and 0.08%, respectively. The in vivo pharmacokinetic parameters under fasting conditions between test and reference formulations (Uroxatral 10 mg extended release tablets) were comparable. The 90% CI, geometric mean ratio (%) and power of C_max, AUCT, and AUCI of the fasting study for the test and reference formulation were 99.03% to 122.78%, 109%, 0.998; 92.94% to 116.71%, 104%, 1; 98.17% to 124.01%, 110% 1, respectively. The scale up biobatch showed negligible difference in in vitro properties with respect to the pilot batch. The formulation developed with these agents was safe to use as there were no serious adverse events developed during the conduction of the clinical trial on the healthy subjects. Furthermore, the developed formulation was bioequivalent with respect to rate and extends of absorption to the reference formulation.

Effect of tamsulosin on spontaneous bladder contraction in conscious rats with bladder outlet obstruction: Comparison with effect on intraurethral pressure

We investigated the effect of tamsulosin, an alpha(1)-adrenoceptor antagonist, on bladder function, especially spontaneous bladder contractions before micturition (premicturition contraction), in conscious rats with bladder outlet obstruction induced by partial urethral ligation, and compared the results with the effect on intraurethral pressure response in anesthetized rats. In obstructed rats, the alpha(1)-adrenoceptor antagonists tamsulosin, naftopidil and urapidil and non-selective alpha-adrenoceptor antagonist phentolamine inhibited premicturition contractions in a dose-dependent fashion. In contrast, yohimbine, an alpha(2)-adrenoceptor antagonist, and atropine, a muscarinic receptor antagonist, hardly inhibited them. Tamsulosin and urapidil showed clearly inhibitory effects on increases in intraurethral pressure induced by phenylephrine, an alpha(1)-adrenoceptor agonist, in the same dose range as that at which they inhibited premicturition contractions, whereas naftopidil required somewhat higher doses to inhibit increases in intraurethral pressure than those at which it inhibited premicturition contractions. In conclusion, premicturition contractions observed in obstructed rats were sensitive to alpha(1)-adrenoceptor antagonists, but not to alpha(2)-adrenoceptor or muscarinic receptor antagonists. Tamsulosin was shown to be effective against both premicturition contraction and intraurethral pressure response in the same dose range in rats. These results partly support the fact that tamsulosin has improved storage symptoms as well as voiding symptoms in patients with lower urinary tract symptoms associated with bladder outlet obstruction by blocking alpha(1)-adrenoceptors.

Effects of tamsulosin on resting urethral pressure and arterial blood pressure in anaesthetized female dogs

The purposes of the present study were to investigate the effects of the alpha1-adrenoceptor antagonists tamsulosin, prazosin and urapidil on resting urethral pressure in anaesthetized female dogs, and to compare the results with their effects on arterial blood pressure. Tamsulosin decreased resting maximal urethral pressure in the urethral pressure profile in a dose-dependent fashion, whereas it had almost no effect on mean arterial blood pressure. Prazosin and urapidil also dose-dependently decreased resting maximal urethral pressure, but these effects were accompanied by decreases in mean arterial blood pressure. Thus, of these three compounds, tamsulosin dose-dependently decreased resting maximal urethral pressure with negligible effect on mean arterial blood pressure in female dogs. These results suggest that tamsulosin will be useful in the treatment of voiding dysfunction associated with bladder outlet obstruction in women, with little hypotensive effect.

Hemodynamic interaction study between the alpha1-blocker alfuzosin and the phosphodiesterase-5 inhibitor tadalafil in middle-aged healthy male subjects

OBJECTIVES

To examine the hemodynamic interactions of the phosphodiesterase type 5 (PDE-5) inhibitor tadalafil with the uroselective alpha1-blocker alfuzosin (10 mg daily), commonly prescribed for benign prostatic hyperplasia-related lower urinary tract symptoms. Erectile dysfunction is commonly associated with lower urinary tract symptoms. PDE-5 inhibitors are the first-line treatment of choice for erectile dysfunction. When co-administered with alpha1-blockers, PDE-5 inhibitors could induce orthostatic hypotension.

METHODS

During each of the two periods of a randomized, double-blind, placebo-controlled, crossover study, 18 healthy middle-aged men received alfuzosin 10 mg daily for 7 days and either a single 20-mg dose of tadalafil or placebo on day 7. The blood pressure and heart rate were monitored before and for 24 hours after tadalafil or placebo.

RESULTS

The combination of tadalafil 20 mg with alfuzosin 10 mg daily elicited a maximal decrease in standing systolic blood pressure that was not significantly different from that after placebo (mean difference 4.35 mm Hg, P = nonsignificant). Analysis of the blood pressure outliers showed that only 1 subject had an asymptomatic standing systolic blood pressure of less than 85 mm Hg. No vasodilatory adverse events were observed with the combined medication.

CONCLUSIONS

In healthy, middle-aged men, tadalafil 20 mg showed no clinically relevant hemodynamic interactions with alfuzosin 10 mg daily.

First-line treatment for symptomatic benign prostatic hyperplasia: is there a particular patient profile for a particular treatment?

When the range of treatment options for benign prostatic hyperplasia (BPH) is as broad as the BPH spectrum of symptoms, how should urologists and their patients choose the best initial treatment? Treatment goals should include reducing both lower urinary tract symptoms and relieving associated morbidities, such as urinary retention, persistent gross hematuria, recurrent infections, bladder stones, or renal insufficiency-which are all indications for surgery. However, if one views BPH as a chronic and progressive disease, should a primary goal of BPH management be the prevention of the BPH-associated morbidities? The goal of this paper is to provide a literature update regarding various treatment options in the setting of initial treatment for symptomatic BPH. Novel approaches to BPH management are discussed. In all cases, the risks and benefits of each treatment need to be considered and discussed with the patient; the decision is ultimately up to the patient and his urologist.

Computational Study of Antagonist/α1A Adrenoceptor ComplexesObservations of Conformational Variations on the Formation of Ligand/Receptor Complexes

As selective antagonist inhibition may relieve the symptoms of benign prostatic hyperplasia, we have examined the interactions of antagonists including quinazoline and imidazolidinium/guanidinium compounds complexed with a homology model of the alpha(1A) adrenoceptor. Our approach involves docking of ligands of various structural classes followed by molecular dynamics simulations of antagonist/receptor complexes, which demonstrates that different structural classes of antagonist induce different receptor conformations upon binding with particular variations noted in the conformation of TM-V. Subsequently, we examined the interactions and the conformational flexibility of alpha(1) and alpha(1A) adrenoceptor antagonists, with the ligand-induced receptor conformers. This study indicated that a receptor conformation induced by one structural class of antagonist is not suitable for direct screening of another class. Our analysis indicates that computational high-throughput screening is likely to give inaccurate data on binding and selectivity and such studies need to consider conformational changes in the receptor.

Comparative molecular dynamics simulations of uncomplexed, 'agonist-bound' and 'antagonist-bound' alpha1A adrenoceptor models

Molecular dynamics simulations (2 ns) were conducted on a homology model of the alpha1A adrenoceptor complexed with agonists and antagonists to examine the various receptor conformations induced. These simulations yield insights into the binding site interactions of the active and inactive states of the receptor. Furthermore, our analysis allowed for the selection of candidate sites for future mutagenesis experiments such as of Glu-180, which may be important for antagonist binding. The interactions of conserved residues of the DRY motif in TM-III and the NPxxY motif in TM-VII in the alpha1A adrenoceptor complexes were also examined. The major differences lie in the role of residue Arg-124, which for the agonist complexes formed additional interactions with residues of intracellular loops I and II. Alternatively, for the antagonist complexes, additional interactions were observed for Asn-322 with residues of TM-II and TM-VII.

Effects of tamsulosin on hypogastric nerve stimulation-induced intraurethral pressure elevation in male and female dogs under anesthesia

The aim of the present study was to investigate the effects of tamsulosin, an alpha(1)-adrenoceptor antagonist, on hypogastric nerve stimulation-induced intraurethral pressure elevation in anesthetized male and female dogs and to evaluate sex differences in these effects. Additionally, the effects of tamsulosin were also compared with those of other alpha(1)-adrenoceptor antagonists, namely prazosin, naftopidil and urapidil. Tamsulosin dose-dependently inhibited hypogastric nerve stimulation-induced intraurethral pressure elevation, with doses required to induce 50% inhibition of the elevation (ED(50) values) of 0.72 and 0.74 microg/kg i.v. in anesthetized male and female dogs, respectively. Mean arterial blood pressure slightly decreased after administration of tamsulosin at a dose which inhibited intraurethral pressure elevation almost completely. Prazosin, naftopidil and urapidil also inhibited increases in intraurethral pressure in a dose-dependent fashion, but caused decreases in mean arterial blood pressure at the same doses. The estimated rank order of inhibitory potency for urethral response was tamsulosin>prazosin>naftopidil=urapidil. In conclusion, tamsulosin dose-dependently inhibited increases in intraurethral pressure with little effect on mean arterial blood pressure in both male and female dogs, and these effects were almost equipotent. These results indicate that tamsulosin will be useful in the treatment of dysuria associated with lower urinary tract symptoms in women as well as men.

A case-based evaluation of SRD5A1, SRD5A2, AR, and ADRA1A as candidate genes for severity of BPH

In men with a clinical diagnosis of benign prostatic hyperplasia (BPH), polytomous logistic regression analysis was conducted to evaluate associations between two silent polymorphisms in SRD5A1 (codon positions 30 and 116), two polymorphisms in SRD5A2 (Val89Leu substitution and C to T transition in intron 1), a trinucleotide (CAG)n repeat in androgen receptor (AR), and an Arg492Cys substitution in ADRA1A and clinical parameters that characterize severity of BPH. Candidate gene selection was based on two mechanistic pathways targeted by pharmacotherapy for BPH: (1) androgen metabolic loci contributing to prostate growth (static obstruction); and (2) factors affecting smooth muscle tone (dynamic obstruction). Polymorphisms in SRD5A2 were not associated with severity of BPH; however, SRD5A1 polymorphisms were associated with severity of BPH. The process(es) in which these silent single-nucleotide polymorphisms (SNPs) influence BPH phenotypes is unknown and additional studies will be needed to assess whether these SNPs have direct functional consequences. The characterization of additional molecular factors that contribute to static and dynamic obstruction may help predict response to pharmacotherapy and serve to identify novel drug targets for the clinical management of BPH.

Formulary Conversion from Doxazosin to Terazosin for the Treatment of Benign Prostatic Hyperplasia in a Small Veterans Hospital

Doxazosin and terazosin are alpha1-adrenergic blockers that are commonly used for the treatment of benign prostatic hyperplasia (BPH). Doxazosin or terazosin can both be given once daily because of their relatively long elimination half-lives (approximately 22 hours for doxazosin, and 9 to 12 hours for terazosin). Common adverse effects of these two drugs include orthostatic hypotension and syncope, especially with the first dose or initial therapy. Based on cost and equivalent efficacy between the two alpha1 blockers, terazosin was selected as the formulary agent for a long-acting alpha1-adrenergic blocker in the Cheyenne Veterans Administrative Medical Center (Cheyenne VAMC). The study was conducted with 12 patients with symptomatic BPH to evaluate the appropriate doses of terazosin when patients taking doxazosin are switched for the treatment of BPH. The results indicated that the two alpha1 blockers provided similar control of BPH symptoms. The mean differences of symptom scores obtained after the two treatment regimens (doxazosin vs terazosin) were not significant (mean ± S.D. 11.17 ± 7.93 vs 9.67 ± 7.48, 95% confidence interval [CI] of the mean difference −1.18 ± 4.18; P = 0.243). No dosage titration was needed at the time of initial switching from doxazosin to terazosin. Additionally, it appears that terazosin doses of 1, 2, 5, 7, and 10 mg can be used initially when doxazosin (at corresponding doses of 1, 2, 4, 6, and 8 mg, respectively) is converted to terazosin for the management of BPH.

First dose efficacy of alfuzosin once daily in men with symptomatic benign prostatic hyperplasia

OBJECTIVES

To evaluate the onset of action of alfuzosin once daily (OD) as determined by uroflowmetry early after initial dosing. Alfuzosin OD is an extended-release formulation of a uroselective, alpha1-adrenoreceptor-blocking agent (alpha-blocker) used in the treatment of lower urinary tract symptoms due to benign prostatic hyperplasia.

METHODS

This was a randomized, placebo-controlled, two-way Latin square crossover study. Forty-nine patients were selected for this study on the basis of their symptomatic improvement during previous treatment with alpha-blockers and significant decreases in urinary flow rate when that treatment was withdrawn.

RESULTS

Our analysis showed that significant increases in the maximal urinary flow rate (Qmax) in 34 assessable patients occurred as soon as 8 hours after the initial dose of medication and persisted for at least 4 days. The DeltaQmax for alfuzosin 10 mg OD was 3.2 mL/s and for placebo it was 1.1 mL/s. The difference of means for the assessable population was 2.1 (95% confidence interval 0.8 to 3.4, P = 0.002). The overall incidence of adverse events was low. Only dizziness, experienced by 3 patients treated with alfuzosin compared with 1 patient treated with placebo, appeared to be related to the study drug.

CONCLUSIONS

Together, our findings suggest that alfuzosin OD exhibits a urodynamically measurable effect on bladder outlet obstruction due to benign prostatic hyperplasia in men with lower urinary tract symptoms within hours of the first administration.

Nonsurgical management of benign prostatic hyperplasia in men with bladder calculi

OBJECTIVES

To assess the outcome of men with bladder calculi who did not undergo transurethral resection of the prostate after endoscopic stone removal. Bladder calculi associated with benign prostatic hyperplasia (BPH) have historically been an absolute indication for transurethral resection of the prostate.

METHODS

A retrospective analysis of the results of 23 men who underwent endoscopic removal of bladder calculi with subsequent medical management of BPH symptoms was performed. Inclusion criteria included men with bladder stones secondary to BPH, serum creatinine 1.6 mg/dL or less, no evidence of hydronephrosis, and no history of acute urinary retention or neurogenic bladder. The International Prostate Symptom Score and postvoid residual urine volume before and after treatment and the incidence of bladder stone recurrence and associated complications were recorded. All patients were treated with either an alpha-receptor blocker or alpha-receptor blocker and finasteride after bladder stone removal.

RESULTS

The follow-up after endoscopic removal of the bladder calculi averaged 30.0 months (range 6 to 96). The International Prostate Symptom Score before and after treatment was 18.3 and 9.4 (P <0.01), respectively. The postvoid residual urine volume before and after treatment was 354 and 179 mL (P <0.01), respectively. Urinary tract infection, acute urinary retention, recurrent calculi, chronic renal insufficiency, or renal failure developed in 21.7% (n = 5), 17.4% (n = 4), 17.4% (n = 4), 4.3% (n = 1), and 0% (n = 0) of the 23 men, respectively. Overall, 18 (78%) did not have any complications.

CONCLUSIONS

Many men with bladder stones can be successfully and safely treated with transurethral stone removal and medical management of BPH.

Preclinical pharmacology of fiduxosin, a novel alpha(1)-adrenoceptor antagonist with uroselective properties

Benign prostatic hyperplasia (BPH), common in aging males, is often treated with alpha(1)-adrenoceptor antagonists. To minimize hypotensive and other side effects, compounds with selective antagonist activity at alpha(1A)- and alpha(1D)- (compared with alpha(1B)-) adrenoceptors were evaluated that would block lower urinary tract alpha(1)-adrenoceptors in preference to cardiovascular alpha(1B)-adrenoceptors. Fiduxosin (3-[4-((3aR,9bR)-cis-9-methoxy-1,2,3,3a,4,9b-hexahydro-[1]-benzopyrano[3,4-c]pyrrol-2-yl)butyl]-8-phenyl-pyrazino[2',3':4,5] thieno-[3,2-d]pyrimidine-2,4(1H,3H)-dione; ABT-980) was tested in radioligand binding assays, isolated tissue bioassays, intraurethral pressure (IUP) tests in isoflurane-anesthetized dogs, and blood pressure analyses in spontaneously hypertensive rats (SHR). Fiduxosin had higher affinity for cloned human alpha(1a)- (0.16 nM) and alpha(1d)-adrenoceptors (0.92 nM) in radioligand binding studies compared with alpha(1b)-adrenoceptors (25 nM) or in isolated tissue bioassays [pA(2) values of 8.5-9.6 for alpha(1A)-receptors in rat vas deferens or canine prostate strips, 8.9 at alpha(1D)-adrenoceptors (rat aorta), compared with 7.1 at alpha(1B)-adrenoceptors (rat spleen)]. Furthermore, the compound antagonized putative alpha(1L)-adrenoceptors in the rabbit urethra (pA(2) value of 7.58). Fiduxosin blocked epinephrine-induced increases in canine IUP (pseudo-pA(2) value of 8.12), eliciting only transient decreases in mean arterial blood pressure (MAP) in SHR. The area under the curve (AUC(0-->60) min) for the hypotensive response was dose related with a log index value for fiduxosin of 5.23, indicating a selectivity of 770-fold comparing IUP to MAP effects. Preferential antagonism of alpha(1A)- and alpha(1D)- versus alpha(1B)-adrenoceptors in vitro, blockade of putative alpha(1L)-sites in vitro, and selective effects on lower urinary tract function versus blood pressure in vivo by fiduxosin suggest the potential utility of this compound for the treatment of BPH.

Impact of medical therapy on transurethral resection of the prostate: a decade of change

OBJECTIVES

To assess whether medical therapy has delayed the need for eventual transurethral prostatectomy (TURP), causing a shift in the population characteristics of men undergoing TURP (ie, older, more comorbidities, more advanced disease), resulting in more complications and poorer outcomes. The introduction of medical therapy for symptomatic benign prostatic hyperplasia (BPH) during the past decade may have changed the indications for TURP.

METHODS

All patients who underwent TURP for symptomatic BPH at our institution in 1988 (before general introduction of medical therapy for BPH) and 1998 (medical therapy the primary initial therapy for BPH) were reviewed. We compared the two groups with respect to the total number of TURPs, indications for surgery, patient age, health status, weight of resected tissue, and preoperative and postoperative complications.

RESULTS

Despite a 16% increase in men at risk of BPH-related events, a 60% decrease in the total number of TURPs performed for symptomatic BPH occurred in 1998 (n = 64) compared with 10 years earlier (n = 157). No significant difference was found in age between the two groups, and no increase in comorbid status was observed. Previous medical management had failed in 36% of men who required TURP in 1998. A significantly higher percentage of patients presented in acute urinary retention (55%) and upper tract obstructive uropathy (12.5%) in 1998 compared with 1988 (23% acute urinary retention and 1.3% obstructive uropathy). Patients in 1998 were healthier, underwent smaller resections, had their catheters removed earlier, and were discharged home earlier. Although they were more likely to be discharged home with a catheter in situ, no significant difference was observed in the incidence of postoperative complications.

CONCLUSIONS

There has been a dramatic decrease in the number of TURPs performed for symptomatic BPH at our institution since the advent of medical therapy. The proportion of TURP patients presenting with urinary retention and hydronephrosis increased, but the average age, medical comorbidities, operative parameters, and postoperative complications have not significantly changed.

Evaluating adverse cardiovascular effects of drug treatment for benign prostatic hyperplasia (BPH): methodological considerations

When studying the effects of drug exposure in diseases with a long asymptomatic clinical course, exposure classification may be biased by the gradually developing "visibility" of the disease. Benign prostatic hyperplasia (BPH) is such a disease. We found that cardiovascular morbidity is two times more prevalent in patients starting drug treatment for BPH when compared to age-matched population controls. This resulted in a difference of cardiovascular prognostic factors between the exposed and non-exposed. This feature can jeopardize the validity of non-randomized comparisons of drug effects. Moreover, the existence of non-treatment strategies, disease under-reporting, and an elderly population with a high baseline risk of experiencing (cardiovascular) outcome events were encountered as methodological problems. When studying adverse cardiovascular effects in patients using BPH products in a non-randomized fashion, an important question is whether we can measure in the database all relevant prognostic factors and use the information for statistical adjustment. This question is an important challenge to observational research and once again stresses the need for control of possible biases in choosing an appropriate study design.

Benign prostatic hyperplasia: challenges for the new millennium

The understanding and therapy of benign prostatic hyperplasia (BPH) has become more complex recently. The molecular mechanisms and growth factors involved in BPH need to be elucidated in the new millennium. The current classification of disease reflects the varied pathophysiologic mechanisms causing lower urinary tract symptoms (LUTS). In addition, symptom scores have improved evaluation of men with BPH, yet 'bother' and 'health-related quality of life' should be better recognized as significant outcome parameters. Clinical evaluation with laboratory markers specific for BPH or LUTS is currently inadequate. Yet, urodynamic evaluation should remain an important aspect of evaluation to guide selection of therapy. Recently medical therapy has expanded to include uroselective alpha blockade and phytotherapy, yet more research is needed. The most significant growth in the field, however, is in minimally invasive therapies of the prostate. Long-term comparative prospective multicenter studies are needed to properly evaluate the outcomes of new technologies compared to traditional procedures that are considered standard of care.

Alpha-adrenergic blocking drugs in the management of benign prostatic hyperplasia: interactions with antihypertensive therapy

Management of benign prostatic hyperplasia (BPH) is often complicated by concomitant hypertension, a life-threatening condition that must be managed optimally. Many of the alpha blockers used to treat BPH also decrease blood pressure, and terazosin and doxazosin have been shown to have significant cardiovascular side effects, such as asthenia/fatigue, postural hypotension, and dizziness when used to treat BPH patients. Furthermore, these drugs are not first-line therapies for hypertension, and the majority of hypertensive BPH patients will be receiving other antihypertensive agents. Therefore, it is possible that the introduction of these drugs will affect blood pressure control, at least temporarily, with possible adverse effects. In contrast, the selective alpha1A blocker tamsulosin does not appear to have significant cardiovascular side effects and produces minimal blood pressure reductions. Therefore, urologists can choose either to use alpha blockers to treat both hypertension and BPH or to treat BPH using alpha blockers that do not interact with antihypertensive therapy. This review focuses on the alpha blockers currently being used to treat BPH, their effects on the cardiovascular system, and their interaction with antihypertensive drugs.