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Table of Contents
ORIGINAL ARTICLE
Year : 2020  |  Volume : 31  |  Issue : 4  |  Page : 188-193

Comparison of the effects of tamsulosin, silodosin, and alfuzosin on catheter-free trials after acute urinary retention due to benign prostatic hyperplasia: A prospective study


1 Department of Urology, Muljibhai Patel Urological Hospital, Nadiad, Gujarat, India
2 Department of Surgical Gastroenterology, Nishtha Surgical Hospital and Research Centre, Patan, Gujarat, India
3 Superintendent Surgeon, Community Health Center, Mahlav, Anand, Gujarat, India
4 Department of Surgery, Pramukhswami Medical College, Karamsad, Gujarat, India
5 Department of Surgery, SSR Medical College, Belle Rive, Mauritius

Date of Submission04-Feb-2020
Date of Decision09-May-2020
Date of Acceptance18-May-2020
Date of Web Publication25-Jul-2020

Correspondence Address:
Rajivkumar Contractor
Superintendent Surgeon, Community Health Center, Mahlav, Anand, Gujarat - 388 450
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/UROS.UROS_11_20

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  Abstract 


Purpose: We compared tamsulosin, silodosin, and alfuzosin in catheter-free trials after acute urinary retention (AUR) due to benign prostatic hyperplasia (BPH). This study aims at assessing the efficacy of tamsulosin, silodosin, and alfuzosin, and the factors affecting the success of catheter-free trials. Materials and Methods: An observational, prospective, randomized study of 49 men with AUR due to BPH was performed from July 2015 to August 2017. Participants were catheterized after the assessment of prevoid urine volume. The prostate size was measured, and IPSS at presentation was calculated. The participants were divided into tamsulosin, silodosin, and alfuzosin groups and were given a catheter-free trial after administration of alpha-blockers for three doses. Descriptive analysis, independent t-test, and Chi-square test were used for data analysis. Univariate and multivariate analyses were done using STATA software version 14.2. P < 0.05 was considered to indicate statistical significance. Results: The overall success of trial without catheter (TWOC) was 62.5% (30 out of 49). There was no difference in the efficacy of tamsulosin, silodosin, and alfuzosin in catheter-free trials after AUR due to BPH. The success of TWOC was affected by median lobe enlargement, and patients with Grade 3 intravesical protrusion of prostate were less likely to have a successful TWOC. Conclusion: TWOC after administration of three doses of alpha-blockers was shown to be useful in most patients irrespective of prostate size. There was no difference in the efficacy of tamsulosin, silodosin, and alfuzosin in catheter-free trials.

Keywords: Acute urinary retention, alfuzosin, silodosin, tamsulosin


How to cite this article:
Parikh A, Yagnik VD, Contractor R, Vyas J, Dawka S. Comparison of the effects of tamsulosin, silodosin, and alfuzosin on catheter-free trials after acute urinary retention due to benign prostatic hyperplasia: A prospective study. Urol Sci 2020;31:188-93

How to cite this URL:
Parikh A, Yagnik VD, Contractor R, Vyas J, Dawka S. Comparison of the effects of tamsulosin, silodosin, and alfuzosin on catheter-free trials after acute urinary retention due to benign prostatic hyperplasia: A prospective study. Urol Sci [serial online] 2020 [cited 2020 Oct 22];31:188-93. Available from: https://www.e-urol-sci.com/text.asp?2020/31/4/188/290856




  Introduction Top


Acute urinary retention (AUR) is a urologic emergency defined as the inability to pass urine that is usually sudden in onset and painful. It is the most common urologic emergency.[1] In males, AUR is most often secondary to benign prostatic hyperplasia (BPH); AUR is rare in females. Historically, the 10-year risk of AUR development in men with BPH was reported to be between 4%[2] and 73%.[3] In this study, a trial without catheter (TWOC) is defined as, when a catheter which has been inserted per urethra for drainage purposes is removed for a trial period of 3 days to determine whether the patient can discharge urine spontaneously without the need for further catheterization. Any interventions which increase the success of TWOC would be considered beneficial for the patients. Taube and Gajraj proposed that urinary retention is caused in part by dynamic factors because a significant proportion of men void spontaneously after catheter placement and removal.[4] If urinary retention is caused by increased sympathetic activity at the level of the prostatic smooth muscle, an alpha-blocker should increase the likelihood of spontaneous voiding after catheter removal. The ideal duration of alpha-blocker dosing before removal of the catheter is unclear, ranging from 1 day to 1 month. Tamsulosin was the most potent alpha-1 antagonist investigated for BPH. Alfuzosin was studied for the treatment of BPH primarily in Europe in the early 1990s. Alfuzosin, though not completely α1A selective, shows greater uroselectivity, whereas tamsulosin and silodosin have higher α1A selectivity.[5] Comparison between two alpha-blockers such as tamsulosin and silodosin has been presented in a few studies. However, the comparison of tamsulosin, alfuzosin, and silodosin for TWOC in AUR has not yet been investigated in any formal study. This study aims at assessing the efficacy of tamsulosin, silodosin, and alfuzosin in catheter-free trials after AUR due to BPH, and to assess the factors affecting the success of TWOC through a prospective randomized study.


  Materials and Methods Top


This prospective study was performed at Pramukhswami Medical College and Shree Krishna Hospital, Karamsad, India. The study was conducted in accordance with the Declaration of Helsinki and was approved by the local Ethics Committee of the institute (IRB number:ECR/331/Inst/GJ/2013). Informed written consent was obtained from all patients prior to their enrollment in this study. We randomized patients with a computer-generated algorithm. A total of 49 patients of BPH with AUR during the time frame of July 2015 to August 2017 were evaluated, then they were randomized into three groups as clarified in [Figure 1]. Group A: tamsulosin; Group B: silodosin; and Group C: alfuzosin. Tamsulosin was given in the dose of 0.4 mg, alfuzosin as 10 mg, and silodosin as 8 mg, all at bedtime. Patients with AUR caused by BPH, who fulfilled all the criteria listed below, were enrolled for the study: Age between 40 and 80 years, enlarged prostate (>20 g), AUR, and willingness to report for follow-up visits on an outpatient basis on predefined dates. The following patients were excluded: prostate size >100 g; those who had taken alpha-blockers or finasteride in the last 6 months; those who were on antipsychotics, anticholinergics, sympathomimetics, or any anti-hypertensive drug; known or suspected prostatic malignancy; previous prostatic surgery or stent; other causes of retention of urine (e.g., neurogenic bladder, bladder neck contracture, urethral stricture, urinary tract infection, bladder malignancy, or acute/chronic prostatitis); and known severe cardiac problems, hypotension, orthostatic hypotension, alcohol abuse, impaired hepatic function, hypersensitivity to the study drugs, mental conditions rendering the subject unable to understand the nature, scope, and possible consequences of the study and/or evidence or uncooperative attitude). Detailed history, followed by systemic and general examination, was recorded. A digital rectal examination was conducted to assess the size, surface, and consistency of the prostate, and the bulbocavernosus and spinal reflexes were checked. Transabdominal ultrasonography was performed to determine the size of the prostate, residual urine, and intravesical bulge of the median lobe of the prostate. IPSS (International Prostate Symptom Score) was calculated at presentation and 2 months after catheter-free trial. Prostate volume was measured with abdominal ultrasound as facilities of TRUS were not available. Median lobe enlargement was seen in nine patients. Grades of median lobe enlargement are as follows: Grade 1: <5 mm; Grade 2: 5–10 mm; and Grade 3: >10 mm. Patients with AUR were carefully examined, and those with AUR due to reasons other than BPH were excluded from the study. The drugs were administered, and the catheter-free trial was performed after 3 days. Those who voided underwent uroflowmetry and post-void residual urine (PVRU) measurements. PVRU more than 150 ml was considered as a failed TWOC. We continued the treatment and followed the patients. Patients who failed to void were re-catheterized and TURP planned. The following parameters were recorded: prostate size, amount of urine retained, the grade of the prostate on DRE, IPSS on presentation, medication is given, TWOC successful or unsuccessful, if successful: Peak flow rate on uroflowmetry, IPSS after successful TWOC, follow-up visits. Patients with a successful TWOC were followed after 2 weeks and the IPSS score was noted.
Figure 1: Randomization process

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  Results Top


The patients were randomized into three groups. Group A (tamsulosin), Group B (Silodosin), and Group C (alfuzosin): The Groups A, B, and C had 18, 17, and 15 patients, respectively. The average prostate size in Group A was 41.2 g, Group B was 41.06 g, and Group C was 44.2 g.

The success of TWOC was as follows: In Group A: out of 18 patients, 11 patients (61.11%). In Group B: out of 16 patients, ten patients (62.5%), and in Group C: out of 15 patients, 9 (60%) patients had successful TWOC as clarified in [Table 1].
Table 1: Successful trial without catheter in each group of patients

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Intravesical prostatic protrusion (IPP)/median lobe: median lobe enlargement was seen in nine patients. Grades of median lobe enlargement are as follows: Grade 1: <5 mm, Grade 2: 5–10 mm, and Grade 3: >10 mm. Two patients had Grade 1, one had Grade 2, and six had Grade 3 enlargement of the prostate. There was a statistically significant difference in successful TWOC between Grade 3, and lower grades of median lobe enlargement. There was also a correlation in the degree of median lobe enlargement and failed TWOC, with 67% patients with Grade 3 (>10 mm) median lobe enlargement as shown in [Figure 2]. The study showed that patients with Grade 3 median lobe enlargement were less likely to benefit from TWOC after AUR.
Figure 2: Difference in success of trial without catheter between Grades 1, 2, and 3 median lobe enlargement

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Peak flow rate: Peak flow rates on uroflowmetry were used to assess adequate voiding and as an endpoint for successful catheter-free trials. All patients who voided have sufficient peak flow rates as listed in [Table 2].
Table 2: Peak flow rate in each group

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IPSS: There was a significant change in the IPSS in all the three groups (P < 0.05) during follow-up at the 2-month interval. However, the difference of change in IPSS between the three groups was statistically not significant (P > 0.05), and a similar effect of all drugs on IPSS was explained in [Table 3]. The difference in IPSS in our study was in the range of 2.9–3.2 points.
Table 3: The Difference in International Prostate Symptom Score between drugs at an Interval of 2 months

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There was a significant change in the IPSS in all the three groups (P < 0.05) during follow-up at the 2-month interval. However, the difference of change in IPSS between the three groups did not reach the statistical significance (P > 0.05).

Prostate size: There was no statistical difference in successful TWOC with prostate size <50 g or >50 g as indicated in [Table 4]. There was no significant difference in the mean prostate size of patients with successful (39.06 g) and unsuccessful TWOC (42.6 g). We have excluded >100 g prostate size from the study. There was no statistical difference in successful TWOC with prostate size <50 g or >50 g. There was no significant difference in the mean prostate size of patients with successful (39.06 g) and unsuccessful TWOC (42.6 g).
Table 4: Success of trial without catheter above and below 50 g prostate size

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  Discussion Top


The goal of treatment for BPH includes relieving LUTS, decreasing BOO (bladder outlet obstruction), improving bladder emptying, ameliorating bladder instability, reversing the renal insufficiency, and preventing future episodes of gross hematuria, urinary tract infection, and urinary retention. The immediate management of AUR requires bladder decompression by catheterization. Evidence that urgent surgery after AUR is associated with higher morbidity and mortality compared to delayed prostatectomy, in part owing to the increased risk of sepsis and bleeding associated with catheterization, has led to the increasing use of TWOC in the past few years. It allowed some patients to avoid surgery and enabled others to schedule the operation in the absence of a catheter. Recent guidelines have stated that a first episode of AUR with successful TWOC may not be a mandatory indication for BPH surgery (AUA guidelines committee, 2003).[6] We used transabdominal ultrasound (TAUS) because transrectal ultrasound (TRUS) facilities were not available and a study conducted by Ajayi et al. stated that TAUS can be utilized in regions where intracavitary probes and/or the expertise are not available as results are comparable.[7] The average prostate size in males is 18 g. We considered prostates >20 g for the study.

The veterans affairs (VA) comparative medical therapy trial provides compelling evidence supporting the use of selective alpha-1 blockers as first-line medical therapy for BPH, irrespective of the prostatic volume. The VA comparative study demonstrated the superiority of alpha-blockers over hormonal therapy for the treatment of clinical BPH.[8] Initially, it was believed that tamsulosin was the most potent alpha-1 antagonist investigated for BPH.[5] Narayan et al.[9] reported the results of a randomized, double-blind, placebo-controlled trial comparing the safety and effectiveness of 0.4 and 0.8 mg of tamsulosin and placebo. Seven hundred and thirty-five men were randomized in the study. The active treatment lasted for 13 weeks. The treatment-related improvements in AUA symptom score and peak flow-rates were comparable with those reported by Lepor et al.[8]

Alfuzosin was investigated for the treatment of BPH primarily in Europe in the early 1990s. Though not completely α1A selective, it shows greater uroselectivity, whereas tamsulosin and Silodosin have higher α1A selectivity. Jardin et al.[10] reported the first large-scale, multicenter, randomized, and placebo-controlled trial demonstrating that alfuzosin was safe and effective for the treatment of BPH. A long-term open-label extension study showed that the effectiveness of alfuzosin was durable up to 30 months.[11]

Alpha-1 blockers have been proved to be a valuable treatment for lower urinary tract symptoms (LUTS) suggestive of BPH. By decreasing the sympathetic tone, they reduce bladder outlet resistance and post-void residual urine volume, the two factors that play a role in the development of AUR. A few studies have shown that alpha-1 blockers improve the rate of successful TWOC.[12],[13] Based on these results, alpha-1 blockers are used routinely before catheter removal and are even considered an appropriate treatment option in the American Urological Association Guidelines (AUA Guidelines, 2003).[6]

Patients in this study were randomly allotted to three groups: alfuzosin (10 mg), tamsulosin (0.4 mg), and silodosin (8 mg). All the drugs were given once daily at bedtime. Constipation was treated in all the patients. The primary objective of the present study was to evaluate and compare the efficacy of alfuzosin, tamsulosin, and silodosin for treating catheterized patients with AUR caused by BPH by comparing those voiding successfully after catheter removal.

The percentage of successful TWOC after administration of tamsulosin was 61.11%, silodosin 62.5%, and alfuzosin 60% as clarified in [Table 1]. The difference between successful TWOC was statistically insignificant when all the drugs were compared (P > 0.005). To our knowledge, there is no other study comparing all the three drugs in AUR due to BPH. Maldonado-Ávila et al. compared the efficacy and safety of tamsulosin and alfuzosin in patients with AUR secondary to BPH. They found that there were no statistically significant differences when comparing both groups, though tamsulosin showed a tendency to be more effective in successful catheter removal.[14] [Table 5] shows a comparison of successful TWOC in various studies.[11],[15],[16],[17],[18],[19],[20],[21] The highest success rate was seen in the study by Kumar et al.[19] and the lowest in the study by Lucas et al.[12] Our study had a comparable success rate.
Table 5: Comparison of successful catheter-free trial in various studies

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Ginka noticed a slightly higher success rate for silodosin when compared to tamsulosin, i.e., 72.33% and 66.7%, respectively.[20] Patil et al. also evaluated tamsulosin and silodosin and found that efficacy with tamsulosin was slightly higher than with silodosin.[21] We compared three drugs (alfuzosin, silodosin, and tamsulosin) and found no significant difference between the three drugs in success after catheter-free trial or IPSS.

Notably, Grade 3 median lobe enlargement (>10 mm) was associated with the decreased success of TWOC. [Figure 2] depicts our results. IPP as a predictor of TWOC success has also been documented in various previous studies [22],[23],[24],[25] as stated in [Table 6].
Table 6: Intravesical protrusion of prostate as a predictor of trial without catheter (four published studies)

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There was no statistical difference in the prostate size of patients who voided and those who did not void (mean size 41.9 g vs. 42.6 g). However, patients with prostates >50 g were less likely to void (57.2%) than those with prostates <50 g (62.5%). We did not find this difference to be statistically significant. On the other hand, Fitzpatrick et al., in a worldwide survey of 6074 men, found a prostate <50 g to be highly significant as a predictor of TWOC success.[26]

All our patients with successful TWOC were assessed for IPSS, post-void residual urine volume, and peak flow rate. In the follow-up period, all patients had a significant decrease in IPSS, with no statistical difference between the three groups. Many randomized placebo-controlled trials, as well as open-label studies, suggest that an improvement of 4–6 points in the IPSS may be expected [27] when treating BPH. Senkul et al.[28] showed a change in IPSS of 2.6–4.2 for those administered alpha-blockers. Our study showed an improvement in IPSS in the range of 2.9–3.2 points. All patients had adequate flow rates and no significant post-void residue.

The major limitation of our study is the small cohort of patients. However, our results may contribute to further studies in this direction.


  Conclusions Top


Alfuzosin, silodosin, and tamsulosin have definite roles in the treatment of patients suffering from AUR due to BPH. All the three drugs improve the IPSS significantly after 2 months of the administration. However, there is no significant difference between the three drugs in success after catheter-free trial or IPSS improvement. The medical management of AUR with selective or sub-selective alpha-blockers is effective as the first line of treatment, and should be offered to all patients with the first episode of AUR due to BPH.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
  References Top

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  [Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6]



 

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