Clinical question
Are α-blockers effective in reducing lower urinary tract symptoms in benign prostatic hypertrophy (BPH)?
Bottom line
As a first-line therapy, α-blockers are effective. Compared with placebo, around 1 in 10 patients have improved BPH symptoms or avoid symptom progression, while about 1 in 50 patients experience hypotension or dizziness. Mainly indirect comparisons suggest doxazosin and terazosin are slightly more effective but have increased risk of adverse events.
Evidence
In a systematic review of 26 RCTs of α-blockers versus placebo, peak urinary flow (Qmax) improved by 1.32 mL/s and International Prostate Symptom Score (IPSS) decreased by 1.92.1
Meta-analysis of 124 RCTs comparing doxazosin, terazosin, alfuzosin, and tamsulosin found improvement in Qmax (by 1.95, 1.21, 1.07, and 1.07 mL/s, respectively) and symptoms (changes in IPSS of −3.67, −3.37, −2.13, and −2.07, respectively).2
-Doxazosin performed statistically significantly better for both outcomes. There was a statistically significant increase in adverse events with doxazosin and terazosin.
A systematic review of 23 RCTs (20 821 patients) compared α-blockers to finasteride3 and found it was inferior to doxazosin and terazosin for Qmax and IPSS at 1 year, but noninferior to tamsulosin. Finasteride and dutasteride are similarly effective.4
An RCT of 3047 men compared placebo with doxazosin, finasteride, and a combination.5 Compared with placebo, doxazosin reduced symptom progression (number needed to treat [NNT] of 15 over 4 years) and increased hypotension (number needed to harm [NNH] of 58) and dizziness (NNH = 48).
In 3 pooled RCTs (955 patients),6 more men taking alfuzosin (76%) had a 3-point improvement or greater in IPSS than men taking placebo did (62%; NNT = 7).
Context
Guidelines recommend α-blockers as first-line therapy in men with symptomatic BPH.7
Clinically meaningful improvement of IPSS is 2 to 6 points or more, depending on baseline score.8
Transurethral resection of the prostate improves Qmax about 10 mL/s and decreases IPSS by 16.7.9
The α-blockers are associated with increased risk of falls (NNH = 589) and fracture (NNH = 1667).10
A 2013 systematic review comparing α-blockers to combination therapy with α-reductase inhibitors showed that combination therapy was effective for enlarged prostates and treatment for longer than 1 year.11
Implementation
Observational data suggest BPH is correlated with obesity and reduced physical activity.12 Predicting progression to urinary retention is difficult, although high prostate gland volume, elevated prostate-specific antigen level, and older age might increase risk.7 In higher-risk patients, it might be reasonable to add α-reductase inhibitors, as they have reduced urinary retention (NNT = 60) and surgical intervention (NNT = 32) over 4 years.5 Side effects including adverse sexual effects (NNH = 15) should be discussed.3
Notes
Tools for Practice articles in Canadian Family Physician (CFP) are adapted from articles published on the Alberta College of Family Physicians (ACFP) website, summarizing medical evidence with a focus on topical issues and practice-modifying information. The ACFP summaries and the series in CFP are coordinated by Dr G. Michael Allan, and the summaries are co-authored by at least 1 practising family physician and are peer reviewed. Feedback is welcome and can be sent to toolsforpractice{at}cfpc.ca. Archived articles are available on the ACFP website: www.acfp.ca.
Footnotes
Competing interests
None declared
The opinions expressed in Tools for Practice articles are those of the authors and do not necessarily mirror the perspective and policy of the Alberta College of Family Physicians.
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