PHILADELPHIA, February 21 - If Viagra (sildenafil) doesn't do the job, maybe all it needs is a kick start with Lipitor (atorvastatin), a small study here suggested.
Eight men with erectile dysfunction who didn't respond to Viagra initially reported that the drug worked better after six weeks of taking Lipitor daily, reported Howard C. Herrmann, M.D., of the Hospital of the University of Pennsylvania here.
Action Points
- Advise patients that the results of this pilot study must be confirmed by a large clinical trial before use of statins to increase the effect of erectile dysfunction drugs can be recommended.
- Advise patients that this study does not support prescribing statins to patients with erectile dysfunction who do not have dyslipidemia.
Results of the study, published in the March issue of the Journal of Sexual Medicine, suggested that erectile dysfunction may be one sign of a generalized vascular disorder characterized by endothelial dysfunction, Dr. Herrmann and colleagues said.
"We theorized that if you could make the endothelium healthier through use of statins -- so that there is more nitric oxide available -- you would improve the endothelial dysfunction and Viagra would work better for the patient," he explained.
A pilot study included 12 Viagra non-responders with mildly elevated LDL cholesterol (greater than 100 mg/dL) and an average age of 58. Eight of the men were randomized to 80 mg of Lipitor daily and four to a placebo. Follow up was at six and 12 weeks.
At 12 weeks, the mean LDL cholesterol of the treatment group decreased by 43%, from a baseline average of 135 mg/dL to 78 mg/dL (P=.012). The placebo group had no significant change.
By six weeks, however, the mean erectile dysfunction score of the treatment group increased by nearly eight points on a 30-point scale, from 10 points (in the range of moderate to severe dysfunction) to 18 points (in the range of mild dysfunction; P=.036). There was no significant increase in the placebo group.
In addition, all eight men in the treatment group reported an improvement in confidence to get and keep an erection, compared with one patient in the placebo group (P=.02).
However, there was no correlation between the degree of LDL lowering and improvement of erectile dysfunction score, the investigators said.
"The frequent coexistence of erectile dysfunction with coronary artery disease and cardiovascular risk factors may prompt further investigation of the lipid status in some patients with erectile dysfunction," the authors said.
"Our study does not provide sufficient rationale for prescribing atorvastatin to patients with erectile dysfunction who do not have dyslipidemia, but it suggests that atherosclerotic risk factor modification could favorably improve erectile dysfunction in patients with or without hyperlipidemia," they added. "Our study strengthens this hypothesis and deserves further testing in a large clinical trial."
The study was supported by Pfizer, maker of both Viagra and Lipitor. Dr. Herrmann has received honoraria from the company.
Primary Source
Journal of Sexual Medicine
Source Reference: Herrmann HC et al. Can atorvastatin improve the response to sildenafil in men with erectile dysfunction not initially responsive to sildenafil? Hypothesis and pilot trial results. Journal of Sexual Medicine. 2006; 3:303-308.