The effect of simvastatin in penile erection: a randomized, double-blind, placebo-controlled clinical trial (Simvastatin treatment for erectile dysfunction-STED TRIAL)

Erectile Dysfunction as a Cardiovascular Risk Factor: Time to Step Up?

BACKGROUND

Erectile dysfunction (ED) is a major health problem that affects a significant proportion of the general population, and its prevalence is even higher in patients with CV risk factors and/or disease. ED and cardiovascular (CV) disease share several common pathophysiological mechanisms, and thus, the potential role of ED as a predictor of CV events has emerged as a significant research aspect.

OBJECTIVE

The purpose of this review is to present and critically discuss data assessing the relation between ED and CV disease and the potential predictive value of ED for CV events.

METHODS

A comprehensive review of the literature has been performed to identify studies evaluating the association between ED and CV disease.

RESULTS

Several cross-sectional and prospective studies have examined the association between ED and CV disease and found an increased prevalence of ED in patients with CV disease. ED was shown to independently predict future CV events. Importantly, ED was found to precede the development of overt coronary artery disease (CAD) by 3 to 5 years, offering a "time window" to properly manage these patients before the clinical manifestation of CAD. Phosphodiesterase type 5 inhibitors are the first-line treatment option for ED and were shown to be safe in terms of CV events in patients with and without CV disease.

CONCLUSION

Accumulating evidence supports a strong predictive role of ED for CV events. Early identification of ED could allow for the optimal management of these patients to reduce the risk for a CV event to occur.

Effects of Preoperative Atorvastatin Treatment On Erectile Function After Radical Prostatectomy: Results From a Subgroup of ESTO1, a Randomized, Double-Blind, Placebo-Controlled Study

INTRODUCTION

Erectile dysfunction is common after radical prostatectomy because of damage to the cavernous nerves. Thus, it is important to identify new ways to avoid this problem. For example, statins have shown positive effects on erectile function and may have anti-inflammatory effects that improve recovery after surgery.

AIM

The aim of this exploratory analysis of a subgroup from ESTO1, a randomized, double-blind, placebo-controlled study, was to evaluate the preoperative use of atorvastatin on erectile function after radical prostatectomy.

METHOD

Patients were randomized to either 80 mg atorvastatin or placebo daily before undergoing radical prostatectomy from study inclusion to the day of surgery. Altogether 118 men with prostate cancer and scheduled for radical prostatectomy were asked to fill out the 5-item version of the International Index of Erectile Function (IIEF-5) questionnaire before surgery and at 3, 6, 9, and 12 months after surgery.

MAIN OUTCOME MEASUREMENTS

The study was exploratory, with the main outcome being the overall difference between IIEF-5 scores in the 2 groups at 12 months. Several hypotheses generating sub-analyses were conducted.

RESULTS

Overall, 85% filled out the IIEF-5 questionnaire before their operation and 85%, 81%, 78%, and 78% completed it at 3, 6, 9, and 12 months follow-up, respectively. 52% of men had information available at all time points. There were no statistically significant differences between the groups at baseline in either erectile function, comorbidities, or tumor characteristics. The median duration of use of atorvastatin and placebo before surgery was 27 and 25 days, respectively. Preoperative atorvastatin treatment had no statistically significant effect on erectile function after prostatectomy as compared with placebo, although IIEF-5 scores were higher at all time points in the statin arm. Furthermore, atorvastatin treatment compared with placebo improved IIEF-5 scores at 12 months after surgery when the cavernous nerves were at least partially intact bilaterally (P < .04, n = 65); however, after full bilateral or unilateral nerve-sparing, the difference was not statistically significant.

CLINICAL IMPLICATION

Short-term statin treatment did not improve recovery of erectile function after prostatectomy; however, further studies are needed before final conclusions.

STRENGTHS & LIMITATIONS

This was a randomized placebo-controlled study. Original ESTO1 study was designed to detect a difference in prostate cancer biomarkers.

CONCLUSION

Short-term atorvastatin treatment before radical prostatectomy had no statistically significant effect on the recovery of erectile functions in a non-selected cohort of patients undergoing radical prostatectomy. Further studies will be needed to clarify the role of long-term atorvastatin use before and after prostatectomy. Siltari A, Riikonen J, Fode M, et al. Effects of Preoperative Atorvastatin Treatment On Erectile Function After Radical Prostatectomy: Results From a Subgroup of ESTO1, a Randomized, Double-Blind, Placebo-Controlled Study. J Sex Med 2019;16:1597-1605.

The role of statins in erectile dysfunction: a systematic review and meta-analysis

To evaluate the effect of statins for erectile dysfunction (ED), a systematic review of the literature was conducted in the Cochrane Library, Embase and PubMed from the inception of each database to June 2013. Only randomized controlled trials (RCTs) comparing treatment for ED with statins were identified. Placebo RCTs with the International Index of Erectile Function (IIEF) as the outcome measure were eligible for meta-analysis. A total of seven RCTs including two statins with a total of 586 patients strictly met our criteria for systematic review and five of them qualified for the meta-analysis. A meta-analysis using a random effects model showed that statins were associated with a significant increase in IIEF-5 scores (mean difference (MD): 3.27; 95% confidential interval (CI):1.51 to 5.02; P < 0.01) and an overall improvement of lipid profiles including total cholesterol (MD: −1.08; 95% CI: −1.68 to −0.48; P < 0.01), low-density lipoprotein (LDL) cholesterol (MD: −1.43; 95% CI: −2.07 to −0.79; P < 0.01), high-density lipoprotein (HDL) cholesterol (MD: 0.24; 95% CI: 0.13 to 0.35; P < 0.01) and triglycerides (TGs) (MD: −0.55; 95% CI: −0.61 to −0.48; P < 0.01). In summary, our study revealed positive consequences of these lipid-lowering drugs on erectile function, especially for nonresponders to phosphodiesterase type 5 inhibitors (PDE5Is). However, it has been reported that statin therapy may reduce levels of testosterone and aggravate symptoms of ED. Therefore, larger, well-designed RCTs are needed to investigate the double-edged role of statins in the treatment of ED.

Pravastatin improves the impaired nitric oxide-mediated neurogenic and endothelium-dependent relaxation of corpus cavernosum in aged rats

AIM

The aim of this study was to investigate the effect of pravastatin treatment on diminished corpus cavernosum (CC) function associated with aging.

METHODS

Male rats were divided into three groups as adult rats (12-14 weeks old), aged rats (72-80 weeks old) and aged rats given 10 mg/kg/d pravastatin in drinking water for six weeks. Blood pressure was measured by tail-cuff method. Total cholesterol, low-density lipoprotein-cholesterol, high-density lipoprotein-cholesterol, triglycerides and testosterone levels were estimated in blood. Changes in expression levels of endothelial nitric oxide synthase (eNOS), phosphorylated eNOS (p-eNOS) (Ser-1177), neuronal nitric oxide synthase (nNOS), NADPH oxidase subunit gp91(phox), Rho A and Rho kinase (ROCK2) in CC were assessed by immunohistochemistry. Nitric oxide (NO)-mediated endothelium-dependent and neurogenic CC relaxation were evaluated by acetylcholine (ACh, 0.1 nM-100 µM) and electrical field stimulation (EFS; 30 V, 5 ms, 2-32 Hz), respectively.

RESULTS

In aged rats, NO-mediated, both endothelium-dependent and neurogenic CC relaxation, were significantly impaired as compared to adult rats. Besides, eNOS, p-eNOS and nNOS expressions decreased significantly in CC from aged rats, while gp91(phox), RhoA and ROCK2 expressions increased significantly. The diminished relaxation in response to ACh or EFS as well as the changes in expression of these proteins in aged rats were significantly improved by pravastatin treatment.

CONCLUSION

Pravastatin improves NO-mediated CC relaxations of aged rats probably by inhibiting NADPH oxidase/Rho kinase pathways, and this effect does not seem to be associated with lipid lowering effect of this drug.

Statins and male sexual health: a retrospective cohort analysis

INTRODUCTION

Conflicting reports exist regarding the role of statins in male gonadal and sexual function. Some studies report a beneficial effect, particularly for erectile dysfunction (ED), through statins' anti-inflammatory and cardiovascular protective properties. Others suggest that statins might be associated with sexual dysfunction through negative effects on hormone levels.

AIM

This study aims to compare the risk of gonadal or sexual dysfunction in statin users vs. nonusers in a single-payer healthcare system.

METHODS

This was a retrospective cohort study of all male patients (30-85 years) enrolled in the Tricare San Antonio market. Using 79 baseline characteristics, we created a propensity score-matched cohort of statin users and nonusers. The study duration was divided into a baseline period (October 1, 2003 to September 30, 2005) to describe patient baseline characteristics, and a follow-up period (October 1, 2005 to March 1, 2012) to determine patient outcomes. Statin users were defined as those prescribed a statin for ≥3 months between October 1, 2004 and September 30, 2005.

MAIN OUTCOME MEASURES

Outcomes were identified as the occurrence of benign prostatic hypertrophy (BPH), ED, infertility, testicular dysfunction, or psychosexual dysfunction during the follow-up period as identified by inpatient or outpatient International Classification of Diseases, 9th Revision, Clinical Modification codes. Logistic regression was used to determine the association of statin use with patient outcomes.

RESULTS

Of 20,731 patients who met study criteria, we propensity score-matched 3,302 statin users with 3,302 nonusers. Statin use in men was not significantly associated with an increased or decreased risk of BPH (odds ratio [OR] 1.08; 95% confidence interval [CI] 0.97-1.19), ED (OR 1.01; 95% CI 0.90-1.13), infertility (OR 1.22; 95% CI 0.66-2.29), testicular dysfunction (OR 0.91; 95% CI 0.73-1.14), or psychosexual dysfunction (OR 1.03; 95% CI 0.94-1.14).

CONCLUSIONS

Statin use was not associated with increased risk of being diagnosed with gonadal or sexual dysfunction in men. Further studies using a larger sample may be needed.

The effect of statins on erectile dysfunction: a meta-analysis of randomized trials

INTRODUCTION

Erectile dysfunction (ED) is common in older men, especially those with comorbidities such as diabetes and atherosclerotic disease, conditions where statins are frequently prescribed.

AIM

To examine the effect of statin therapy on ED using the five-item version of the International Inventory of Erectile Function (IIEF).

METHODS

We performed a random-effects meta-analysis of studies identified by a systematic search of MEDLINE, Web of Knowledge, the Cochrane Database, and ClinicalTrials.gov. Examination of the 186 retrieved citations resulted in the selection of 11 randomized trials for inclusion in the meta-analysis.

MAIN OUTCOME MEASURES

Change in the IIEF score.

RESULTS

IIEF increased by 3.4 points (95% CI 1.7-5.0, P = 0.0001) with statins compared to control. This effect remained statistically significant after multiple sensitivity analyses, including analysis for publication bias, a cumulative meta-analysis, and 11 repeated analyses with each study omitted sequentially. The increase in IIEF with statins was approximately one-third to one-half of that previously reported with phosphodiesterase-5 inhibitors and larger than the effect of lifestyle modification. Metaregression showed an increase in benefit with decreasing lipophilicity. The average age of participants and the degree of LDL cholesterol lowering did not alter the effect on IIEF.

CONCLUSION

Statins cause a clinically relevant improvement of erectile function as measured by the five-item version of the IIEF.

Neuropsychiatric adverse events associated with statins: epidemiology, pathophysiology, prevention and management

Statins, or 3-hydroxy-3-methyl-glutaryl coenzyme A reductase inhibitors, such as lovastatin, atorvastatin, simvastatin, pravastatin, fluvastatin, rosuvastatin and pitavastatin, are cholesterol-lowering drugs used in clinical practice to prevent coronary heart disease. These drugs are generally well tolerated and have been rarely associated with severe adverse effects (e.g. rhabdomyolysis). Over the years, case series and data from national registries of spontaneous adverse drug reaction reports have demonstrated the occurrence of neuropsychiatric reactions associated with statin treatment. They include behavioural alterations (severe irritability, homicidal impulses, threats to others, road rage, depression and violence, paranoia, alienation, antisocial behaviour); cognitive and memory impairments; sleep disturbance (frequent awakenings, shorter sleep duration, early morning awakenings, nightmares, sleepwalking, night terrors); and sexual dysfunction (impotence and decreased libido). Studies designed to investigate specific neuropsychiatric endpoints have yielded conflicting results. Several mechanisms, mainly related to inhibition of cholesterol biosynthesis, have been proposed to explain the detrimental effects of statins on the central nervous system. Approaches to prevent and manage such adverse effects may include drug discontinuation and introduction of dietary restrictions; maintenance of statin treatment for some weeks with close patient monitoring; switching to a different statin; dose reduction; use of ω-3 fatty acids or coenzyme Q10 supplements; and treatment with psychotropic drugs. The available information suggests that neuropsychiatric effects associated with statins are rare events that likely occur in sensitive patients. Additional data are required, and further clinical studies are needed.