The exact mechanism responsible for this effect is still open for debate. A salutatory side effect of the news may be the impact on medication adherence among men with both elevated LDL-C and erectile dysfunction.
Erectile dysfunction (ED), which can affect an estimated 18 to 30 million men in the United States, may be an early sign of endothelial dysfunction and poor vascular health. Although there are many potential causes for ED, vascular disease remains a leading pathophysiologic mechanism. This effect of statin therapy in patients with ED remains controversial as LDL-C lowering may affect the lipid precursor for testosterone. Conversely, the pleiotropic effects of statin therapy may improve overall vascular health.
In a highly publicized meta-analysis, presented at the American College of Cardiology Scientific Sessions 2014 and simultaneously published in The Journal of Sexual Medicine, statin therapy was shown to improve lipid profiles as well as ameliorate ED in 647 men who had both conditions. Eleven randomized controlled trials in which ED was assessed were identified from the 186 results of a search conducted by the authors of Medline, Web of Knowledge, Cochrane Database, and ClinicalTrials.gov. In all studies, men completed the International Inventory of Erectile Function (IIEF) survey, which consists of five questions, each scored on a five-point scale, with lower values representing worse sexual function.
There was an average of 53 patients per study with a mean age of 57.8 years; statin therapy was given for approximately 4 months with a mean decrease in LDL-C in treated men that ranged from 138 mg/dL to 91 mg/dL (47 mg/dL). Using a random-effects meta-analysis, the authors reported an increase in the IIEF of approximately 24% [3.4 points (95% CI 1.7-5.0, p=0.001)] in patients treated with statins vs controls. This effect persisted despite multiple sensitivity analyses as well as with systematic exclusion of each of the individual trials. The magnitude of these effects was considerable-improvement in IIEF was estimated to be approximately one-third to one-half of that seen with phosphodiesterase inhibitors. Results remained independent of age and degree of LDL-C lowering.
The benefits of statin therapy continue to grow in number and indications for their use seem to be ever-expanding. Perhaps these results are another demonstration of the pleiotropic effects of statins on endothelial function. This latest study, although limited by the fact that duration of statin treatment was short and the individual studies were quite small, provides important data to justify a larger placebo controlled randomized clinical trial. In the meantime, providers can feel assured using statins in patients with ED. Furthermore these results can be used as a patient education tool to encourage more patients, especially those with ED, to improve compliance with statin therapy.
Kostis JB, Dobrzynski JM. Effect of statins on erectile dysfunction: a meta-analysis of randomized trials. J Sex Med. 2014 Mar 29. doi: 10.1111/jsm.12521.