Statins Versus PDE-5 Inhibitors
Authors: Chakaravarthy Pradeep , Vadlamani Bharat , Kant Ravi , Chauhan Udit , Kapre Meenakshi , Mittal Ankur 
Published: August 2023

Background:
Atherosclerosis of penile vasculature and endothelial dysfunction are the main causes of erectile dysfunction (ED) in diabetes. Phosphodiesterase type 5 inhibitors (PDE5i) have been playing a significant role in the management of ED for around 40 years. As there are many promising studies about the effect of statins on endothelial dysfunction and symptomatic improvement in ED, we did this study to compare the effect of statins with PDE-5i.

Aim:
To study and compare the effect of statins and PDE-5i in ED patients with controlled diabetes mellitus.

Materials and Methods:
A randomized open-label parallel noninferiority institutional and comparative study was conducted in the Department of Internal Medicine, All India Institute of Medical Sciences Rishikesh, over a period of 12 months. Clinical and objective assessment of ED was based on the International Index of Erectile Function (IIEF)-5 questionnaire and peak systolic velocity (PSV) using Doppler, respectively. The study population was divided into two groups, of which one received atorvastatin 40 mg once daily at night time and the other group received sildenafil 100 mg once daily at night time. Baseline penile Doppler before therapy and 4 weeks after therapy was done. The effects of atorvastatin and sildenafil were compared with P value and statistical values.

Outcomes and Results:
A total of 79 patients were enrolled, of which 19 patients were excluded from the study due to their unwillingness. Quantitative variables were compared using Independent t test/Mann–Whitney test between the two groups and Wilcoxon signed-rank test was used for comparison between preintervention and postintervention groups. Qualitative variables were correlated using Chi-square test/Fisher’s exact test. The mean preintervention PSV in the atorvastatin group was 8.94 cm/s with a standard deviation of 8.15 cm/s, and the mean preintervention PSV in the sildenafil group was 10.04 cm/s with a standard deviation of 9.21 cm/s with a P value of 0.537 and 95% confidence interval (CI). The mean postintervention PSV in the atorvastatin group was 9.15 cm/s with a standard deviation of 8.22 cm/s, and the mean postintervention PSV in the sildenafil group was 10.67 cm/s with a standard deviation of 9.28 cm/s with a P value of 0.327 and 95% CI.

Conclusions:
Sildenafil has already been recognized as efficacious in ED and has been in use for almost 4 decades. In our study, we compared the effect of sildenafil and atorvastatin among diabetic patients between 40 and 70 years of age. Sildenafil has already shown significant subjective benefits to patients, as assessed through questionnaires. However, it did not reach a statistically significant value (PSV) within a one-month period. Nonetheless, when compared with statins, PDE5 inhibitors (PDE5i) demonstrated a positive subjective and objective response, as observed by the mean PSV difference between the two groups. Statins on the other hand have recently been studied for its pleiotropic effects on vascular smooth muscle. The role of statins is comparatively not up to the mark for PDE5i. Hence, we conclude this study with the finding that neither statins nor PDE5 inhibitors (PDE5i) demonstrated a significant increase in PSV at the end of the one-month period. Furthermore, it is evident that additional future studies and data collection are necessary to investigate the long-term effects of these treatments, as well as the combined effects of statins and PDE5i. Additionally, further research is needed to explore novel drugs and therapies for the treatment of erectile dysfunction (ED).