Incidence Of Acute Urinary Retention Research Articles

High intensity focused ultrasound (HIFU) treatment of BPH: results of a multi-center phase III study

The five centers phase III trial was to show that HIFU can treat prostate tissue thermally for symptomatic relief of BPH and improve flow rates. At five sites, 68 BPH patients were treated with the Sonablate device (Focus Surgery, Inc. Indianapolis, IN). A urethral Foley catheter was inserted into the urethra to aid in positioning and was kept in-situ during the treatment. A cooling device was used to cool the rectal wall. The patients returned home within a few hours after the procedure. The Foley catheter was kept electively to avoid any incidence of acute urinary retention following the therapy. The catheter was removed after 4–5 days. The average treatment time was 38 minutes. The patients were treated without pain, blood loss or complications. At 90 days post treatment, average Qmax and AUA Symptom Scores improved from 8.7 ml/s to 12.66 ml/s (48%) and 23.06 to 11.62 (52%), respectively. Significant prostate tissue changes took place before and after the treatment. 80% of the patients had cavity formation at the site of treatment at the bladder neck and prostate. Nonsurgical HIFU therapy is safe and effective for providing symptomatic relief of BPH symptoms and the treatment can be performed as an outpatient procedure.

Alfuzosin: a clinically uroselective α1-blocker.

A once-daily (o.d.) formulation of alfuzosin has recently been developed in order to improve the convenience of dosing and to provide optimal pharmacokinetic coverage over a 24-h period. The results of two double-blind, placebo-controlled phase III studies of similar design that included 983 patients with LUTS that suggested BPH have confirmed that alfuzosin 10mg o.d. is a 24-h effective treatment for both symptoms and flow rates, and that there is no additional benefit in using a higher dosage. In addition, alfuzosin is the only α1-blocker that has demonstrated a significant decrease in post-void residual urine, a known risk factor for acute urinary retention, as well as the incidence of acute urinary retention in comparison with a placebo. Administered without an initial dose titration, alfuzosin 10mg o.d. is well tolerated, with a low incidence of postural hypotension (<1%) and no significant changes in blood pressure compared with a placebo, even in elderly and hypertensive patients. Ejaculation disorders were rarely reported and did not show an evident causal relationship to treatment. Alfuzosin 10mg o.d. also exhibits an excellent sexual side-effect profile, with no deleterious impact on this important aspect of quality of life for BPH patients.

Do Alpha-Blockers Prevent the Occurrence of Acute Urinary Retention?

Acute urinary retention (AUR) is a common complication of benign prostatic hyperplasia (BPH) and the incidence varies widely from 0.4 to 25% per year in men seen in urology practices. It has been estimated that AUR is the indication for surgery in around 25–30% of patients undergoing transurethral resection of the prostate (TURP) and that emergency TURP for AUR is associated with greater morbidity than elective TURP. Risk factors for AUR include lower urinary tract symptoms (LUTS), depressed peak urinary flow rate, enlarged prostate, high postvoid residual (PVR) urine and old age. Alfuzosin has been shown to significantly increase maximum flow rate and relieve bladder outlet obstruction, resulting in a reduction in PVR urine. A pooled analysis of 11 placebo-controlled studies involving 1,470 patients with LUTS suggestive of BPH indicates that significantly greater improvements were observed in patients treated with alfuzosin than with placebo. A 6-month placebo controlled study of 518 patients reported a 0.4% incidence of AUR in the alfuzosin group compared with a 2.4% incidence with placebo (p = 0.04). These positive effects on PVR could be related to the reduction in incidence of AUR seen in alfuzosin-treated patients.

Alpha(1)-Blocker therapy in the nineties: focus on the disease.

Therapy for benign prostatic hyperplasia has evolved rapidly over the last decade, with the introduction in the early 1990s of new agents such as alpha(1)-blockers and 5alpha-reductase inhibitors. The major advantage of alpha(1)-blockers over 5alpha-reductase inhibitors is their rapid onset of action. Maximum flow rate is improved after first administration and optimal symptom relief is usually reached within 2-3 months. In addition, alpha(1)-blockers are effective regardless of prostate size and they provide a similar degree of symptom relief in patients with or without bladder outlet obstruction. The main adverse events with the alpha(1)-blockers relate to their effects on the cardiovascular system (postural hypotension) and central penetration (asthenia, somnolence). Newer uroselective alpha(1)-blockers, such as alfuzosin and tamsulosin, have a better safety profile and, as such, do not require initial dose titration. Alfuzosin has also been shown in a six-month study to significantly reduce both residual urine and the incidence of acute urinary retention (AUR) compared with placebo. In addition, alfuzosin is effective in improving the success rate of a trial without catheter in patients with AUR.

INCIDENCE RATES AND RISK FACTORS FOR ACUTE URINARY RETENTION: THE HEALTH PROFESSIONALS FOLLOWUP STUDY

Purpose We define incidence rates and risk factors for acute urinary retention. Materials and Methods In 1992, 41,276 United States male health professionals 45 to 83 years old self-reported baseline health data and American Urological Association symptom index scores. In 1995 a subset reported the year of any episode of acute urinary retention requiring catheterization. Of 8,418 respondents 6,100 without a history of prostate cancer, prostatectomy or acute urinary retention before 1992 provided data. Incidence rate from 1992 to 1995 were calculated and risk factors were assessed using logistic regression. Results During 15,851 person-years of followup 82 men reported an episode of acute urinary retention (sampling weighted incidence 4.5/1,000 person-years, 95% confidence intervals 3.1 to 6.2). Rates increased with age and baseline symptom severity. In men with symptom score 0 to 7 (none or mild lower urinary tract symptoms) the incidence of acute urinary retention increased from 0.4/1,000 person-years for those 45 to 49 years old to 7.9/1,000 person-years for those 70 to 83 years old. In men with symptom score 8 to 35 (moderate or severe lower urinary tract symptoms) rates increased from 3.3/1,000 person-years for those 45 to 49 years old to 11.3/1,000 person-years for those 70 to 83 years old. Men with a clinical diagnosis of benign prostatic hyperplasia and a symptom score 8 or greater had the highest rates (age adjusted incidence 13.7/1,000 person-year). All 7 lower urinary tract symptoms comprising the American Urological Association symptom index individually predicted acute urinary retention (age adjusted odds ratio 1.8 to 2.9 for symptoms occurring more than 25% of the time during the last month). The sensation of incomplete bladder emptying, having to void again after less than 2 hours and a weak urinary stream were the best independent symptom predictors. Use of medications with adrenergic or anticholinergic side effects also predicted acute urinary retention. Conclusions Acute urinary retention occurred relatively infrequently but older age, moderate or severe lower urinary tract symptoms, a diagnosis of benign prostatic hyperplasia and specific drug therapies significantly increased the risk of occurrence.

Defining the implant treatment volume for patients with low risk prostate cancer: does the anterior base need to be treated?

Purpose: An increased incidence of acute urinary retention has been reported after interstitial prostate radiation therapy when the anterior base of the prostate gland receives 100% of the prescription dose. The frequency of prostate cancer in this location as a function of the pre-treatment prostate specific antigen (PSA), biopsy Gleason score, and 1992 American Joint Commission on Cancer Staging (AJCC) was determined. Methods and Materials: One hundred four men treated at the Brigham and Women’s Hospital with radical prostatectomy for clinically localized prostate cancer between 1995–1996 comprised the study population. Prostatectomy specimens were whole mounted and the location of each tumor foci enumerated. Results: Of 269 foci of prostate cancer found in 39 low-risk prostate cancer patients (PSA < 10 ng/ml, biopsy Gleason score ≤ 6, and 1992 AJCC clinical stage T 1c,2a), a single focus (0.37%) was noted in the anterior base. Conversely, 20/355 (5.6%) and 18/251 (7.2%) tumor foci were noted in the anterior base in 43 patients with intermediate risk and 24 patients with high-risk disease, respectively. Conclusions: A new definition of the treatment volume excluding the anterior base for low-risk prostate cancer patients may be justified.

Finasteride: an update of its use in the management of symptomatic benign prostatic hyperplasia.

Finasteride inhibits type 25alpha-reductase activity, significantly reducing dihydrotestosterone levels. Consequent reductions in prostate volume, increases in urinary flow rates and improvements in symptoms compared with placebo have been observed in trials of up to 4 years' duration and in noncomparative extensions (for up to 6 years). Results from the 4-year placebo-controlled PLESS trial show finasteride to significantly reduce the risk of benign prostatic hypertrophy (BPH)-related acute urinary retention and the requirement for surgical intervention. Finasteride has significantly greater efficacy in patients with a large prostate (> or = 40 ml) than in patients with a small prostate. However, the predictive value of prostate size has been questioned. Results of an earlier comparative 1-year trial show terazosin monotherapy and terazosin plus finasteride therapy to be significantly more effective than both finasteride monotherapy and placebo in reducing symptom scores and improving maximum urinary flow rates. Prostatic volume was significantly reduced by finasteride monotherapy and combination therapy only. The overall efficacy of finasteride in patients with mild to moderate symptomatic BPH tended to be greater than that of serenoa repens (Permixon) in a 6-month trial. A US cost analysis model indicates that finasteride and terazosin are less expensive than transurethral resection of the prostate (TURP) during the first 2 years of initiation. Canadian cost-effectiveness and cost-utility analyses using decision analysis modelling have shown primary intervention with finasteride to provide more quality-adjusted life years (QALYs) at lesser cost than watchful waiting or TURP in patients with moderate symptoms who receive the drug for < or = 3 years and < or = 14 years, respectively, but fewer QALYs at a higher cost in patients with severe symptoms needing therapy for > or = 4 years. Confirmatory prospective economic studies are required. Finasteride appears to improve overall quality of life to a similar extent to serenoa repens; patient satisfaction appears similar with finasteride and TURP. Finasteride is generally well tolerated. Most commonly reported adverse effects are sexually related (1 to 2.1 %). Gynaecomastia has been reported in 0.4% of patients. Despite modest improvements in maximum urinary flow rates and symptom scores, finasteride is a first-line treatment option in those with moderate uncomplicated BPH, especially in patients with a large prostate (> or = 40 ml). It is also an option in patients with more severe symptoms who are unable or unwilling to undergo surgery and in those awaiting surgery. Importantly, finasteride appears to reduce disease progression, significantly decreasing the incidence of acute urinary retention and the requirement for surgical intervention; to date, no other pharmacological agent has been shown to reduce these outcomes.

Long-Term Implications of Medical Therapy on Benign Prostatic Hyperplasia End Points

There is a progression over time of relevant measurable benign prostatic hyperplasia (BPH) end points including symptoms, flow rates, prostate size, complications such as acute urinary retention (AUR), and surgical rates. Only two classes of medical therapy, the α-blockers and a 5-α-reductase inhibitor, have shown unequivocal and consistent efficacy over placebo in 1-year studies. Both of these classes of medications have demonstrated relative long-term safety. Finasteride has been shown in three large, 2-year, randomized, controlled studies to be superior to placebo, and both finasteride and the α-blockers have demonstrated long-term efficacy and safety in open-label studies. The efficacy of finasteride is significantly enhanced when it is used in patients with large prostates. Long-term finasteride therapy also results in a significant reduction in the incidence of AUR and the need for surgery. Long-term medical therapy for BPH is effective and safe. Data are now available that allow clinicians to analyze the long-term risks and benefits of the various medical options and subsequently rationalize long-term therapy for individual patients.

A Placebo Controlled Double Blind Study Using Perioperative Prazosin in the Prevention of Urinary Retention Following Inguinal Hernia Repair

Acute urinary retention is a frequent complication following inguinal hernia repair. The smooth muscle of the bladder neck and the prostate have been demonstrated to be rich in alpha-1 adrenergic receptors. It has been postulated that the aetiology of acute urinary retention postoperatively is at least partially due to adrenergic stimulation, blocking these receptors may reduce the incidence of acute urinary retention. We have used prazosin in a double blind, placebo controlled study to establish its efficacy in the prevention of acute urinary retention in patients undergoing elective inguinal hernia repair. A total of 70 male patients were enrolled; 36 patients had been allocated active drug and 34 patients had been allocated placebo. Only two patients developed acute urinary retention. Both patients had been allocated prazosin and had received a general anaesthetic for their hernia surgery. In either arm of the study, a higher number of patients developing urinary retention would have been expected but this may be explained by the greater vigilance on urinary output by nursing staff aware that the trial was being conducted. On the basis of our findings, we do not recommend the routine use of perioperative prazosin with inguinal hernia repair. Further studies in high risk groups would be necessary to assess more fully the efficacy of prazosin in this situation.

Natural History of Prostatism: Risk Factors for Acute Urinary Retention

Purpose We determined the occurrence of and risk factors for acute urinary retention in the community setting. Materials and Methods A cohort of 2,115 men 40 to 79 years old was randomly selected from an enumeration of the Olmsted County, Minnesota population (55% response rate). Participants completed a previously validated baseline questionnaire that assessed symptom severity, and voided into a portable urometer to measure peak urinary flow rates. A 25% random subsample underwent transrectal sonographic imaging of the prostate to determine prostate volume. Followup was performed through a retrospective review of community medical records to determine the occurrence of acute urinary retention in the subsequent 4 years. Results During the 8,344 person-years of followup 57 men had a first episode of acute urinary retention (incidence 6.8/1,000 person-years, 95% confidence interval [CI] 5.2, 8.9). Among men with no to mild symptoms (American Urological Association symptom index score 7 or less) the incidence of acute urinary retention increased from 2.6/1,000 person-years among men 40 to 49 years old to 9.3/1,000 person-years among men 70 to 79 years old. By contrast, rates increased from 3.0/1,000 person-years for men 40 to 49 years old to 34.7/1,000 person-years among men 70 to 79 years old among men with moderate to severe symptoms (American Urological Association symptom index score greater than 7). Men with depressed peak urinary flow rate (less than 12 ml. per second) were at 4 times the risk of acute urinary retention compared with men with urinary flow rates greater than 12 ml. per second (95% CI 2.3, 6.6). Men with an enlarged prostate (greater than 30 ml.) experienced a 3-fold increase in risk (95% CI 1.0, 9.0, p = 0.04). Conclusions Lower urinary tract symptoms, depressed peak urinary flow rates, enlarged prostates and older age are associated with an increased risk of acute urinary retention in community dwelling men. These findings may help to identify men at increased risk of acute urinary retention in whom closer evaluation may be warranted.