To evaluate the effect of statins for erectile dysfunction EDa systematic review of the literature was conducted in the Cochrane Library, Embase and PubMed from the inception of each database to June A total of seven RCTs including two statins with a total of 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: In summary, our study revealed positive consequences of these lipid-lowering drugs on erectile function, especially for nonresponders to phosphodiesterase vytorin and sexual dysfunction 5 inhibitors PDE5Is.
However, it has been reported that statin therapy may reduce levels of testosterone and aggravate symptoms of ED. Therefore, larger, vytorin and sexual dysfunction, well-designed RCTs are needed to investigate the double-edged role of statins in the treatment of ED. Erectile dysfunction ED is defined as the persistent inability to attain and maintain an erection sufficient to permit satisfactory sexual performance.
It is now widely accepted that ED can be a consequence of a generalized vascular disorder caused by endothelial dysfunction. Endothelial dysfunction is considered to be the main factor resulting in PDE5Is treatment failure 8 because PDE5Is are unlikely to reverse endothelial dysfunction with reduced NO bioavailability. Statin is an inhibitor of the enzyme 3-hydroxy-methylglutaryl-CoA reductase. It suppresses the conversion of 3-hydroxy-methylglutaryl-CoA to mevalonate, which vytorin and sexual dysfunction the rate-limiting step in de novo synthesis of cholesterol.
In addition, it was reported that statin therapy was associated with reduced levels of testosterone and even symptoms of hypogonadism. Thus, we integrated all qualified randomized controlled trials RCTs available and conducted a systematic review and meta-analysis of these studies to assess the effects of statins on the quality of erections for patients with ED.
A comprehensive search of databases, including Cochrane Library, Embase and PubMed, was conducted from the inception of each database to June The search was restricted to published English articles. Computer searches used combinations of medical subject headings or other keywords i.
We tried to contact all corresponding authors when data were found to be missing. After the studies were reviewed, it was noted that none of the previously performed meta-analyses of RCTs reported statins as a treatment for ED.
With articles identified, seven studies were retrieved that were RCTs 17181920212223 Figure 1. The International Index of Erectile Function IIEF is a validated and widely used multidimensional, self-report instrument for the evaluation of male sexual function. Included studies compared treatment with statins against a control placebo or no treatment. Characteristics and outcome variables in individual RCTs are listed using standard forms. Process of study selection. The articles were retrieved and assessed for inclusion according to the above criteria by two independent researchers.
Dispute between the investigators over inclusion of a study was resolved by a discussion. The quality of included studies were assessed by the Cochrane Risk-of-Bias Tool, attributing one point to each item total score range: Meta-analyses were performed for the primary and secondary outcomes.
Mean differences MDs were calculated for continuous variables and a random effects model was applied because of the limited number of studies. Statistical heterogeneity was expressed as the I 2 index as described by Higgins and colleagues. Our systematic review included a total of patients, vytorin and sexual dysfunction, with a dropout rate ranging from 0 to The mean participant age was The primary findings of five studies was an improvement of erectile function after statins administration, 1718192021 whereas, the other two studies had no significant difference between the statins and the control groups.
The statin used was atorvastatin in five trials, 17181920vytorin and sexual dysfunction, 21 and simvastatin in the other two trials. Four trials investigated patients with an inadequate response to sildenafil, which is commonly used as one type of PDE5Is.
One study included two phases of trials, with an additional intake of vardenafil for 4 weeks after the initial 6 months of daily simvastatin or placebo. Atorvastatin was investigated in three trials, 171819 and simvastatin was investigated in two trials. Therefore, our vytorin and sexual dysfunction indicate that statins were associated with a significant improvement in erectile function. Pooled estimate of IIEF-5 scores between statins and control groups.
The lipid profile analyses from the five studies included in the meta-analysis of IIEF-5 scores is listed in Table 4. In our quantitative analysis, statins were associated with a significant decrease in total cholesterol MD: Pooled estimate of total cholesterol levels between statins and control group. Pooled estimate of LDL cholesterol levels between statins and control groups. Pooled estimate of triglycerides levels between statins and control groups.
Pooled estimate of HDL cholesterol levels between statins and control groups. Our pooled estimates from these studies had obvious heterogeneity in the IIEF-5 scores and lipid profiles. We tried to explain the heterogeneity by performing subgroup analyses involving trial duration, types of statins, additional PDE5Is regimens and responsiveness to PDE5Is. Two studies were not included in the quantitative analysis described above.
One was a double-blind, placebo-controlled trial, 21 and the other was a single-blind, no treatment controlled trial. The other study demonstrated that atorvastatin alone improved erectile function with approximately a seven-point increase in ED domain scores compared with not using any medication.
The effect vytorin and sexual dysfunction statin treatment is more obvious in patients with elevated LDL cholesterol levels. To our knowledge, vytorin and sexual dysfunction, this is the first systematic review and meta-analysis of RCTs investigating the effects of statins for the treatment of ED. The seven RCTs in our systematic review, vytorin and sexual dysfunction, which were published between andstudied two statins, atorvastatin and simvastatin.
In our meta-analysis, we identified vytorin and sexual dysfunction placebo-controlled RCTs that evaluated vytorin and sexual dysfunction two statins for the treatment of patients with ED.
The pooled results across all five trials demonstrated a significant increase in IIEF—5 scores by 3. The minimal clinically important difference in the erectile function domain is accepted to be a four-point improvement in the IIEF-5 score. However, the MD of 3. Our meta-analysis has the following limitations: Sildenafil was only administered continuously in patients whose IIEF-5 scores were still under 21 after sildenafil therapy.
Another potential mechanism for statin efficacy on erectile function is the modification of endothelial function. A previous study showed that treatment with atorvastatin increased plasma NO concentrations, 32 which was consistent with the outcomes in the most recent trial in our review, vytorin and sexual dysfunction.
Through the effects of statins, the cyclic guanosine monophosphate levels improved, and smooth muscle relaxation was restored through increased arterial blood flow, leading to improved erectile function.
Furthermore, we found that the efficacy of statins for the treatment of ED was associated with modulated lipid levels. Accordingly, larger, well-designed, RCTs should investigate the correlation between dyslipidemia correction and erectile function.
Although statins exert potential beneficial effects on ED through the aforementioned mechanisms, they have also been reported to have a negative influence on erectile function. In a prospective observational study, 93 male patients starting on lipid-lowering therapy were recruited from the cardiology and lipid clinics and 82 completed the IIEF-5 questionnaire, vytorin and sexual dysfunction. After statin administration, the median IIEF-5 score decreased significantly to 6.
Before statin therapy, no correlation was observed between IIEF-5 score and any individual cardiovascular risk factor. After 6 months of statin administration, lower IIEF scores correlated significantly with age, diabetes and weakly with cigarette smoking. However, a recent meta-analysis of RCTs assessed the effects of lifestyle interventions and pharmacotherapy for cardiovascular risk factors, including statins, on the severity of ED.
It demonstrated that cardiovascular disease-related interventions and pharmacotherapy were associated with significant improvement in erectile function. Treatment for these cardiovascular risk factors could improve erectile function in patients with ED.
Previous systematic reviews containing case reports, review articles and information from clinical trials suggested that statins may cause ED.
They found that both total and free testosterone levels were significantly lower in patients taking statins compared with those not using lipid-lowering drugs.
The use of statins also correlated with a reduced testicular volume and a higher prevalence of hypogonadism-related symptoms and type 1 diabetes and heart problem, as assessed by higher ANDROTEST scores. Based on these outcomes, they concluded that statin therapy might induce an overt primary hypogonadism and may vytorin and sexual dysfunction considered as a risk factor for ED.
This negative effect of statins on testosterone levels were attributed to the suppression of presqualenic steroid synthesis within the testis by inhibiting mevalonate formation, thus interfering with testosterone production.
Therefore, it is necessary to evaluate the effect of statins on hormone metabolism in more RCTs with high-quality and large sample sizes. Theoretically, statins seem to be a double-edged therapy for patients with ED. Although our study revealed positive consequences of these lipid-lowering drugs on erectile function, vytorin and sexual dysfunction, especially for patients with no response to PDE5Is, the study was limited in the number of RCTs included and high heterogeneity existed in the meta-analysis.
Hence, additional large, well-designed RCTs with high-quality are needed to explore the general effects of statins for the treatment of ED. KJW provided the original ideas and instructed the writing of this article. XC and YT researched and assessed the literature. XC also wrote the manuscript. All authors read and approved the final manuscript. National Center for Biotechnology InformationU.
Journal List Asian J Androl v. Published online Feb This is an open-access article distributed under the terms of the Creative Commons Attribution-Noncommercial-Share Alike 3, vytorin and sexual dysfunction.
This article has been cited by other articles in PMC. Abstract To evaluate the effect of statins for erectile dysfunction EDa systematic review of the literature was conducted in the Cochrane Library, Embase and PubMed from the inception of each database to June Identification of articles and data extractions After the studies were reviewed, it was noted that none of the previously performed meta-analyses of RCTs reported statins as a treatment for ED.
Open in a separate window. Quality assessment of included studies The articles were retrieved and assessed for inclusion according to the above criteria by two independent researchers. Data synthesis and data analysis Meta-analyses were performed for the vytorin and sexual dysfunction and secondary outcomes.
Table 2 Characteristics of the randomized clinical studies included in the systematic review. Table 3 IIEF-5 scores of clinical trials before and after treatment. Table 4 Variable outcomes of lipid parameters before and after treatment, vytorin and sexual dysfunction. Other trials Two studies were not included in the quantitative analysis described above.
Guidelines on male sexual dysfunction: