David E Hinojosa-Gonzalez et al., 2024: Indirect assessment of low-intensity shockwave therapy's energy density and pulse frequency for erectile dysfunction: a systematic review, bayesian network meta-analysis and meta-regression

The article focuses on the use of low-intensity extracorporeal shockwave therapy (Li-ESWT) as a treatment for erectile dysfunction (ED). ED, defined as the persistent inability to maintain an erection sufficient for sexual activity, is a condition with increasing prevalence with age and is linked to cardiovascular health. Traditional treatments for ED include phosphodiesterase-5 inhibitors (PDE5is), injections, and devices, with PDE5is being the most common. However, many patients discontinue PDE5is due to side effects or reduced efficacy.
Li-ESWT is an emerging treatment, particularly for vasculogenic ED, and works by potentially enhancing endothelial function and promoting angiogenesis. The article presents a systematic review and Bayesian network meta-analysis to evaluate the effectiveness of Li-ESWT, considering variables such as energy density and pulse frequency.
A Bayesian network is a graphical model that represents probabilistic relationships among a set of variables using directed acyclic graphs (DAGs). In the context of the article, a Bayesian network meta-analysis involves:
Integrating Evidence: Combining results from multiple studies that might not be directly comparable. This approach accounts for variations in study designs, treatment protocols, and populations.
Probabilistic Modeling: Estimating the relative effectiveness of different treatments or interventions based on indirect comparisons, using Bayesian methods to account for uncertainty and derive probability distributions for treatment effects.
Ranking and Decision Making: Ranking treatments based on their estimated effectiveness and making informed decisions about which treatment might be best, given the available evidence.
Key findings of the review include:
Energy Density: The most effective energy setting was 0.15 mJ/mm², which significantly improved erectile function as measured by the International Index of Erectile Function (IIEF) score.Lower and higher energy settings were less effective, possibly due to insufficient or excessive stimulation.
Number of impulses per session: 1500 pulses per session was found to be the most effective frequency.More than 3000 pulses per session were less effective, and radial waves, which have lower intensity and penetration, did not show significant benefits. This is in contrast to other studies and reviews, where 3000 Shocks were recommended (6x 500 to the proximal & distal shaft and the ventral side)
Concomitant Use of PDE5is: The use of PDE5is alongside Li-ESWT showed a slight negative impact on treatment outcomes, suggesting that Li-ESWT may be more effective as a standalone treatment. This is also very interesting, since mostly a combination therapy is recommended.
Study Limitations: Heterogeneity among the studies in terms of control groups, follow-up times, and the use of different versions of the IIEF questionnaire.The need for further high-quality randomized controlled trials to validate these findings, with consistent reporting on energy delivery, frequency, and follow-up intervals.
The article provides a comprehensive analysis of Li-ESWT as a treatment for ED, particularly focusing on its effectiveness based on different energy densities and pulse frequencies. The findings suggest that Li-ESWT can be a viable treatment option, particularly at specific settings (0.15 mJ/mm² and 1500 pulses/session). However, the effectiveness of Li-ESWT appears to diminish with lower or higher settings, indicating a possible "dose-response" relationship.
Radial shock waves were less favored primarily due to their lower intensity and penetration capabilities, which appear insufficient for treating ED effectively compared to focused shock waves. Clinical evidence from the studies reviewed indicated that radial shock waves did not produce significant improvements in erectile function. As a result, the article concluded that focused shock waves, particularly at specific energy densities and pulse frequencies, offer better therapeutic outcomes for ED.
The preference for focused shock waves in this context reflects their ability to deliver higher-intensity, targeted treatments that are more likely to induce the desired physiological responses in the penile tissues.
One of the significant points raised by the article is the importance of standardizing treatment protocols in clinical trials. The variation in energy settings, pulse frequencies, and the use of different versions of the IIEF score across studies makes it challenging to draw definitive conclusions. This underlines the need for future studies to adopt more rigorous and consistent methodologies to ensure comparability and reliability of results.
Moreover, the article highlights the potential of Li-ESWT to improve erectile function without significant side effects, making it a promising alternative for patients who do not respond well to traditional treatments. However, the slight negative impact of concurrent PDE5i use raises questions about the optimal use of Li-ESWT in clinical practice, suggesting that more research is needed to understand how these therapies can be best combined or whether Li-ESWT should be prioritized as a first-line treatment in certain cases.
In conclusion, while the findings are promising, they also emphasize the need for further research, particularly randomized controlled trials that can confirm the optimal settings for Li-ESWT and establish it as a standardized treatment for ED

Jens Rassweiler