Sexual Function Outcomes of 5-Year Rezum Treatment vs. Drug Therapy for BPH

Rezum patients gained sexual desire and erectile function at 1 year; every drug regimen caused significant declines across multiple sexual domains

Journal: The Journal of Sexual Medicine | Published: 2026-05-11 | Type: Secondary cohort comparison using data from two RCTs | PMID: 42117741 Authors: Han TM et al. (Loyola University Medical Center, Department of Urology) Funding/COI: Funded by Boston Scientific, Inc. (manufacturer of Rezum); individual author COI not disclosed

Summary

This paper compares 5-year sexual function outcomes between MTOPS trial participants on drug therapy (doxazosin, finasteride, combination, or placebo; n=1,157) and a cohort from the Rezum RCT who received water vapor thermal therapy (WVTT; n=86 sexually active men). The two cohorts used entirely different sexual function questionnaires—a fundamental problem the authors paper over with percentage-change normalization. The conclusion that Rezum spares sexual function while BPH drugs harm it is directionally plausible, but the cross-trial design prevents the numbers from carrying the weight the authors place on them.

Claims

• Finasteride and combination therapy produced significant worsening of sexual desire, erectile function, ejaculatory function, and overall sexual satisfaction over 5 years
• Doxazosin caused significant declines in sexual desire, erectile function, and ejaculatory function; overall sexual satisfaction was preserved
• WVTT patients showed a significant increase in sexual desire and erectile function at 1-year follow-up
• WVTT patients showed a significant increase in overall sexual satisfaction over 5 years
• WVTT was associated with approximately -10% decrease in ejaculatory function from baseline at years 3–5, compared to approximately -20% for combination drug therapy

Study Quality

This is not a head-to-head randomized trial. It is a retrospective cohort comparison drawing from two separate RCTs—MTOPS and the Rezum RCT—with matched eligibility criteria for LUTS severity and prostate size. The core methodological defect: the two cohorts used entirely different validated instruments. MTOPS participants completed the Brief Male Sexual Function Inventory (BMSFI); Rezum participants completed the IIEF-15 and Male Sexual Health Questionnaire (MSHQ). These instruments overlap but are not equivalent. The authors use percentage change from baseline within a linear mixed repeated measures model to normalize across instruments—a reasonable attempt, but it cannot resolve the underlying mismatch.

The sample size disparity is substantial. The drug arms enrolled 1,157 participants; the WVTT arm included 86 sexually active men. Eighty-six is a thin foundation for 5-year sexual function conclusions. The abstract reports "little attrition" as a strength but provides no absolute dropout counts.

Red Flags

• Industry-funded: Boston Scientific manufactures Rezum—the device whose favorable outcomes are the paper's central claim
• Different questionnaires in each arm: BMSFI vs. IIEF-15 + MSHQ; percentage normalization mitigates but does not eliminate the problem
• WVTT arm n=86 vs. drug arms n=1,157—statistical power is severely asymmetric throughout
• No direct randomization between WVTT and pharmacotherapy; "Randomized Controlled Trial" in the article type refers to each source trial internally, not the cross-trial comparison presented here
• Individual author COI not disclosed despite manufacturer funding
• Abstract reports statistical significance without p-values, confidence intervals, or absolute effect sizes

Strengths

• MTOPS is one of the largest and most rigorously conducted BPH trials ever run (NIH-funded, 5-year follow-up, 1,157 randomized participants)
• Five-year follow-up is long enough to distinguish durable effects from transient ones
• Eligibility matching on LUTS severity and prostate size reduces confounding between cohorts
• Percentage-change normalization is a defensible methodological bridge across dissimilar instruments

Verdict

The established harms of finasteride and combination therapy on sexual function are not news, and MTOPS data documenting them over 5 years is the most credible part of this paper. The Rezum comparison is where it gets shaky: cross-trial cohort matching with mismatched instruments, a Boston Scientific funding source, and 86 men in the treatment arm of interest add up to a result that can generate hypotheses but not settle the question. This paper is useful for its long-term pharmacotherapy data. The Rezum versus drugs framing is secondary analysis dressed as a head-to-head trial.