Testosterone replacement in men with sexual dysfunction

BACKGROUND

Clinical practice guidelines recommend testosterone replacement therapy (TRT) for men with sexual dysfunction and testosterone deficiency. However, TRT is commonly promoted in men without testosterone deficiency and existing trials often do not clearly report participants' testosterone levels or testosterone-related symptoms. This review assesses the potential benefits and harms of TRT in men presenting with complaints of sexual dysfunction.

OBJECTIVES

To assess the effects of testosterone replacement therapy compared to placebo or other medical treatments in men with sexual dysfunction.

SEARCH METHODS

We performed a comprehensive search of CENTRAL (the Cochrane Library), MEDLINE, EMBASE, and the trials registries ClinicalTrials.gov and World Health Organization International Clinical Trials Registry Platform, with no restrictions on language of publication or publication status, up to 29 August 2023.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) in men (40 years or over) with sexual dysfunction. We excluded men with primary or secondary hypogonadism. We compared testosterone or testosterone with phosphodiesterase-5 inhibitors (PDEI5I) to placebo or PDE5I alone.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened the literature, assessed the risk of bias, extracted data, and rated the certainty of evidence (CoE) according to GRADE using a minimally contextualized approach. We performed statistical analyses using a random-effects model and interpreted them according to standard Cochrane methodology. Predefined primary outcomes were self-reported erectile dysfunction assessed by a validated instrument, sexual quality of life assessed by a validated instrument, and cardiovascular mortality. Secondary outcomes were treatment withdrawal due to adverse events, prostate-related events, and lower urinary tract symptoms (LUTS). We distinguished between short-term (up to 12 months) and long-term (> 12 months) outcomes.

MAIN RESULTS

We identified 43 studies with 11,419 randomized participants across three comparisons: testosterone versus placebo, testosterone versus PDE5I, and testosterone with PDE5I versus PDE5I alone. This abstract focuses on the most relevant comparison of testosterone versus placebo. Testosterone versus placebo (up to 12 months) Based on a predefined sensitivity analysis of studies at low risk of bias, and an analysis combing data from the similar International Index of Erectile Function (IIEF-EF) and IIEF-5 instruments, TRT likely results in little to no difference in erectile function assessed with the IIEF-EF (mean difference (MD) 2.37, 95% confidence interval (CI) 1.67 to 3.08; I² = 0%; 6 RCTs, 2016 participants; moderate CoE) on a scale from 6 to 30 with larger values reflecting better erectile function. We assumed a minimal clinically important difference (MCID) of greater than or equal to 4. TRT likely results in little to no change in sexual quality of life assessed with the Aging Males' Symptoms scale (MD -2.31, 95% CI -3.63 to -1.00; I² = 0%; 5 RCTs, 1030 participants; moderate CoE) on a scale from 17 to 85 with larger values reflecting worse sexual quality of life. We assumed a MCID of greater than or equal to 10. TRT also likely results in little to no difference in cardiovascular mortality (risk ratio (RR) 0.83, 95% CI 0.21 to 3.26; I² = 0%; 10 RCTs, 3525 participants; moderate CoE). Based on two cardiovascular deaths in the placebo group and an assumed MCID of 3%, this would correspond to no additional deaths per 1000 men (95% CI 1 fewer to 4 more). TRT also likely results in little to no difference in treatment withdrawal due to adverse events, prostate-related events, or LUTS. Testosterone versus placebo (later than 12 months) We are very uncertain about the longer-term effects of TRT on erectile dysfunction assessed with the IIEF-EF (MD 4.20, 95% CI -2.03 to 10.43; 1 study, 42 participants; very low CoE). We did not find studies reporting on sexual quality of life or cardiovascular mortality. We are very uncertain about the effect of testosterone on treatment withdrawal due to adverse events. We found no studies reporting on prostate-related events or LUTS.

AUTHORS' CONCLUSIONS

In the short term, TRT probably has little to no effect on erectile function, sexual quality of life, or cardiovascular mortality compared to a placebo. It likely results in little to no difference in treatment withdrawals due to adverse events, prostate-related events, or LUTS. In the long term, we are very uncertain about the effects of TRT on erectile function when compared to placebo; we did not find data on its effects on sexual quality of life or cardiovascular mortality. The certainty of evidence ranged from moderate (signaling that we are confident that the reported effect size is likely to be close to the true effect) to very low (indicating that the true effect is likely to be substantially different). The findings of this review should help to inform future guidelines and clinical decision-making at the point of care.

Serenoa repens for the treatment of lower urinary tract symptoms due to benign prostatic enlargement

BACKGROUND

Benign prostatic hyperplasia (BPH) is a non-malignant enlargement of the prostate, which can lead to obstructive and irritative lower urinary tract symptoms (LUTS). The pharmacologic use of plants and herbs (phytotherapy) for the treatment of LUTS associated with BPH is common. The extract of the berry of the American saw palmetto or dwarf palm plant, Serenoa repens (SR), which is also known by its botanical name of Sabal serrulatum, is one of several phytotherapeutic agents available for the treatment of BPH.

OBJECTIVES

To assess the effects of Serenoa repens in the treatment of men with LUTS consistent with BPH.

SEARCH METHODS

We performed a comprehensive search of multiple databases (the Cochrane Library, MEDLINE, Embase, Scopus, Web of Science, and LILACS), trials registries, other sources of grey literature, and conference proceedings published up to 16 September 2022, with no restrictions on language or publication status.

SELECTION CRITERIA

We included randomized controlled trials of participants with BPH who were treated with Serenoa repens or placebo/no treatment.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies for inclusion at each stage and undertook data extraction and risk of bias assessment and GRADE assessment of the certainty of the evidence. We considered review outcomes measured up to 12 months after randomization as short term, and beyond 12 months as long term. Our main outcomes included urologic symptom scores, quality of life, and adverse events.

MAIN RESULTS

For this update, we narrowed the review question to only comparisons with placebo. We included 27 studies (of which 9 were new) involving a total of 4656 participants, 19 studies comparing Serenoa repens with placebo, and 8 studies comparing Serenoa repens in combination with other phytotherapeutic agents versus placebo. Most studies included men aged > 50 (mean age range 52 to 68) with moderate urologic symptoms (International Prostate Symptom Score [IPSS] range 8 to 19). Ten studies were funded by the pharmaceutical industry; two studies were funded by government agencies; and the remaining studies did not specify funding sources. Serenoa repens versus placebo or no intervention Results for this comparison are based on predefined sensitivity analyses limited to studies at low risk of bias. Serenoa repens results in little to no difference in urologic symptoms at short-term follow-up (3 to 6 months; IPSS score range 0 to 35, higher scores indicate worse symptoms; mean difference (MD) -0.90, 95% confidence interval (CI) -1.74 to -0.07; I2 = 68%; 9 studies, 1681 participants; high-certainty evidence). Serenoa repens results in little to no difference in the quality of life at short-term follow-up (3 to 6 months; IPSS quality of life domain range 0 to 6, higher scores indicate worse quality of life; MD -0.20, 95% CI -0.40 to -0.00; I2 = 39%; 5 studies, 1001 participants; high-certainty evidence). Serenoa repens probably results in little to no difference in adverse events (1 to 17 months; risk ratio (RR) 1.01, 95% CI 0.77 to 1.31; I2 = 18%; 12 studies, 2399 participants; moderate-certainty evidence). Based on 164 cases per 1000 men in the placebo group, this corresponds to 2 more (38 fewer to 51 more) per 1000 men in the Serenoa repens group. Serenoa repens results in little to no difference in urologic symptoms at long-term follow-up (12 to 17 months, IPSS score, MD 0.07, 95% CI -0.75 to 0.88; I2 = 34%; 3 studies, 898 participants; high-certainty evidence). Serenoa repens results in little to no difference in quality of life at long-term follow-up (12 to 17 months, IPSS quality of life, MD -0.11, 95% CI -0.41 to 0.19; I2 = 65%; 3 studies, 882 participants; high-certainty evidence). There were no data on long-term adverse events for this comparison. Serenoa repens in combination with other phytotherapy versus placebo or no intervention Different phytotherapeutic agents that include Serenoa repens may result in little to no difference in urologic symptoms compared to placebo at short-term follow-up (12 to 24 weeks, IPSS score, MD -2.41, 95% CI -4.54 to -0.29; I2 = 67%; 4 studies, 460 participants; low-certainty evidence). We are very uncertain about the effects of these agents on quality of life (very low-certainty evidence). These agents may result in little to no difference in the occurrence of adverse events; however, the CIs included substantial benefits and harms (12 to 48 weeks, RR 0.91, 95% CI 0.58 to 1.41; I2 = 0%; 4 studies, 481 participants; low-certainty evidence). Based on 132 cases per 1000 men in the placebo group, this corresponds to 12 fewer (55 fewer to 54 more) per 1000 men in the combined phytotherapeutic agents with Serenoa repens group.

AUTHORS' CONCLUSIONS

Serenoa repens alone provides little to no benefits for men with lower urinary tract symptoms due to benign prostatic enlargement. There is more uncertainty about the role of Serenoa repens in combination with other phytotherapeutic agents.