Author, date and country | Patient group | Study type (level of evidence) | Outcomes | Key results | Study Weaknesses |
---|---|---|---|---|---|
Tiong et al, 2009, Singapore | 67 men presenting with initial episode of spontaneous AUR secondary to BPH. Patients catheterised then randomised to receive placebo or Alfuzosin for 2 days. | Double-blind prospective RCT. | Primary outcome – rate of successful TWOC after 2 days. | Significantly greater proportion of patients in Alfuzosin group (21/35 or 60%) had successful TWOC compared with placebo group (11/32 or 34%) (p=0.036). | Initial data published in 2006 & included in Cochrane review below. Further patients added to initial set to form this published work. Still a small data set, ~30 patients in each arm. This may be too small to detect all predictive factors. |
Secondary outcome – intravesical prostatic protrusion (IPP) detected by transabdo-minal USS | Patients with grade 3 IPP (>10mm) had a significantly lower chance of successful TWOC (p=0.04) compared to grade 1 (<5mm) and 2 (6-10mm). Remained a significant independent predictor for failed TWOC (p=0.034) on multivariate analysis. This highlights the importance of prostate size as an independent negative predictor of successful TWOC on alpha-blocker. | ||||
Zeif & Subramonian (Cochrane review) 2009 UK | 696 men in AUR secondary to BPH (5 trials ranging from 44-360 patients) 4 studies used Alfuzosin and 1 used Tamsulosin. 4 used the intervention between 24-72hrs before TWOC and the other for 8 days. | Systematic review and meta-analysis of 5 double-blind prospective RCTs comparing alpha-blocker with placebo from UK, USA and Singapore. | Primary outcome – successful TWOC. | 4 studies favoured alpha-blocker & 1 favoured placebo. Overall rates of successful TWOC tended to favour alpha-blocker over placebo. Statistically significant (RR 1.39, 95% CI 1.18 to 1.64) irrespective of alpha-blocker used (Alfuzosin RR 1.31, 95% CI 1.1 to 1.56; Tamsulosin RR 1.86, 95% CI 1.17 to 2.97) | (1) Lack of internationally agreed outcome measures for what constitutes successful TWOC: (a) return to satisfactory voiding without need for re-catheterisation within 24hrs (b) ability to void with residual volume of <200ml (c) flow rate >5ml/s with voided volume >100ml & residual volume <200ml (d) successful voiding with residual volume <150ml (2) Only 1 study clearly described method of randomisation & allocation concealment; others stated randomisation but no description of methods or of concealment (3) Different drugs compared for different time periods is also a problem |
Prevention of recurrent urinary retention after successful TWOC. | 1 study showed a favourable outcome for Tamsulosin over placebo that was statistically significant (RR 0.70, 95% CI 0.54 to 0.91). Effect only described for acute phase of study & not long term. Others assessed AUR relapse after successful TWOC but done during 2nd phases of studies where both successful alpha-blocker & placebo participants either re-randomised or continued on alpha-blocker treatment, so these data could not be used for analysis | ||||
Need for prostatic surgery. | Although assessed in some studies, this outcome measure could not be assessed as both groups pooled together in one group following successful TWOC & either randomised again or continued (or commenced) on alpha-blocker | ||||
Persistent lower urinary tract symptoms. | In 2nd phase (re-random-isation of successful TWOC patients) 1 study found significant improvement with alpha-blocker compared with placebo at 6/12 (IPSS 8.75 versus 11.45, p=0.012; bother score 1.66 versus 2.27, p=0.004). Due to re-randomisation could not use data as part of pre-defined 2y outcomes | ||||
Post-void residual volumes. | Although one study reported on this outcome, numbers too small to draw meaningful conclusion (RR 0.82, 95% CI 0.16 to 4.24) | ||||
International Prostate Symptom Score (IPSS). | 1 study described statistically significant improvement with alpha-blocker compared with placebo (IPSS alpha-blocker 8.75 vs placebo 11.45, p=0.012; bother score with alpha-blocker 1.66 vs placebo 2.27, p=0.004) | ||||
Alpha-blocker side effects (SEs). | SEs described included dizziness, somnolence, fainting, headache, postural hypotension or hypotension, malaise & syncope. 3 studies eligible for assessment. With regard to causing fewer side effects, 2 studies in favour of placebo & 1 favoured alpha- blockers. Overall outcome favoured placebo (RR 1.13, 95% CI 0.69 to 1.85) but not statistically significant. | ||||
Drop-out rates. | Main reason was need for re-catheterisation. Vaso-dilatation-related SEs caused less drop-outs. | ||||
Prieto et al, 2008, Spain | 65 patients with AUR secondary to BPH. 47 evaluable, 46 compliant. 22 had doxazosin (born in even-numbered years), 24 no medication (born in uneven-numbered years) TWOC’d at 1 month. | Quasi-RCT. | Post-void residual volume measurement and flowmetry as markers of successful TWOC at 6 months, 1 year and 2 years. | 15/22 (69%) in treatment arm developed AUR within 24 years; 7/22 (31%) successful TWOC. 16/24 (67%) in control group developed AUR within 2 years; 8/24 (33%) successful TWOC. Therefore, no statistical difference between groups in terms of drug efficacy. | No blinding – medication or no medication Groups nicely homogenous for age, prostate volume and blood pressure but very small in number, perhaps giving rise to a type I error. |
Desgrandchamps et al, 2006, France | 2618 men with AUR enrolled by 658 French urologists. | Prospective cross-sectional survey. | Successful TWOC. | Of 1906 men who had a TWOC, 79% received an alpha-blocker (mainly Alfuzosin) before catheter removal. TWOC was successful in 50.2% and success the rate was significantly higher in men receiving alpha-blocker (53.0% vs 39.6%, p<0.001) before TWOC. In men receiving alpha-blocker, success rate of TWOC also higher (55.2% vs 69.3%) when catheter removed after 1-3 days than for longer duration of catheterisation (45.6% vs 48.6%). | Differences in clinical profile (spontaneous & precipitated AUR). BPH found in 52.3% with pAUR compared with 25.9% with sAUR. Those without BPH therefore having smaller prostates are more likely to succeed. |
Abeygunasekera et al, 2001, Sri Lanka | 100 consecutive patients with 1st episode of AUR secondary to clinically benign enlarged prostate. All given Prazosin for 1 week then TWOC’d. Successful participants continued drug for 6 months. | Prospective cohort study. | Successful TWOC. | 56/94 (60%) initial success. Further 12 of these developed urinary retention during follow up and required surgery. Therefore, 47% successful TWOC at 6 months. | Large proportion (71%) of patients had prostates <20g when clinically assessed which is more likely to yield a successful TWOC. |
Kim et al, 2001, USA | 33 consecutive men with AUR. All given Tamsulosin for at least 4 days before TWOC. Successful TWOCs continued drug and followed up at 2 weeks, 3 months and regularly after for a median of 6.5 months. | Cohort study. | Successful TWOC. | 26/33 (79%). A further 3 had at least 4 days more Tamsulosin and passed a 2nd TWOC to yield 29/33 (88%). | Small cohort study (n=33) where all patients given the drug. All 8 with pAUR had successful TWOC compared with 50% with sAUR. Again, these different aetiologies grouped together to draw conclusions. |
TURP/ISC during follow up. | 9 (27%). | ||||
Mean symptom score | 12.9 at 2 weeks, 11.9 at 3 months. | ||||
QoL score. | 2.7 at 2 weeks, 2.8 at 3 months. Correlated strongly with failure of medical therapy. | ||||
Post-void residual volume. | 111ml at 2 weeks, 61.7 at 3 months. Correlated strongly with failure of medical therapy. | ||||
Mean peak urinary flow rate. | 7.7ml/s at 3 months. | ||||
Pandit et al, 2008, India | 68 patients (age range 50-91 years, mean 66.1) presenting with spontaneous AUR over a 1-year period. 57 diagnosed as having BPH and most of these had 3-15 days of alpha-blocker (Terazosin, Prazosin or Tamsulosin) prior to TWOC. | Retrospective analysis of data from a prospective observational study. | Successful TWOC at 1 week. | 57 patients diagnosed with BPH, of which 45 had TWOC and 12 scheduled instead for earliest possible elective surgery. 31 (68.9%) had successful TWOC. Overall success rate was 70%. Amongst those diagnosed with BPH, mean age, symptom score and prostate volume were recorded, with only symptom score showing a statistically significant difference between the successful and unsuccessful TWOC groups. | Observational nature of study is surely its greatest weakness. Single-centre study but they use 3 different alpha-blockers over a wide-range of days prior to TWOC, and Finasteride was advised in addition for those with a larger prostate. Unclear even how many were given alpha-blockers, or how a diagnosis of BPH was achieved, other than presumptively. 2 patients excluded without reasons given. Huge element of bias based on their selective TWOC idea. 12 were not TWOC’d but scheduled for surgery and 15 were designated to be a UTI rather than BPH, so only given antibiotics, but often retrospectively found to have more evidence for the other diagnosis or even both. |
Lo et al, 2010, Hong Kong | 248 patients (mean age 71, range 50-93) presenting with 1st episode of AUR secondary to BPH & who could void successfully after initial TWOC following treatment with alpha-blocker over a 4-year period. 19 (7.7%) given Terazosin, 214 (86.3%) given Doxazosin, 15 (6.0%) given Doxazosin gastrointestinal therapeutic system. Most patients (82.3%) received 1 dose prior to TWOC. | Prospective cohort study. | Primary outcome – failed medical treatment within 5-year follow up period. | During this follow up period medical therapy failed for 118 (47.6%) patients, most commonly for recurrent AUR. Percentage of patients with medical failure at 6, 12, 24 & 60 months was 11.6, 14.3, 28.4 & 50.5% respectively. | Calculations appear to have been based on the population assuming that the 23 patients who died & 1 lost to follow-up all had successful medical therapy. 436 originally presented with 1st episode of AUR secondary to BPH & therefore 188 failed TWOC initially with alpha-blocker in addition to those who subsequently failed during this follow up period. Different drugs & little detail about when TWOC’d, especially in respect to alpha-blocker doses. Cohort study, so many factors in play, rather that RCT comparing placebo and alpha-blocker, which would have been nicer. Relatively older study population may be a potential reason for failure, because role of age-related detrusor changes may also predispose to failure. |
Multivariate analysis to discover significant predictors of medical failure after successful TWOC. | Prostate size >50ml & serum PSA level during AUR >10ng/ml. Those with neither risk factor had a 5-year success rate of 63.8% compared with 29.4% for those patients with both risk factors, which was significantly lower (p<0.001). |