Editor—Last year Jackson reported on five men who developed impotence with profound lethargy and inertia after starting treatment with or increasing the dose of simvastatin. This resolved after treatment was discontinued.1 The author also cited reports of impotence with this drug from Australia.
Impotence is not uncommon in middle aged and elderly men, the group most commonly prescribed lipid lowering drugs. The frequency and nature of the disorder introduce potential bias into investigations such as those conducted by Jackson—namely, stopping the drug and watching or rechallenging with the drug (in two cases) without control patients. The message given to patients when a statin is prescribed is important for how they tolerate the drug in the future. If patients get the impression that their future health and survival will depend on taking a drug that interferes with some fundamental parts of their body systems for the rest of their lives, some will react with temporary lethargy and impotence. Patients will be eager to blame external factors and will be relieved if their doctor suggests a reason for the problem. Only placebo controlled randomised clinical trials can answer the question of whether there is really a connection between impotence and treatment with simvastatin. In the Scandinavian simvastatin survival study, 4444 patients with coronary heart disease were randomised to treatment with simvastatin or placebo for up to 6.2 years.2 The table gives the numbers spontaneously reporting temporary or permanent impotence or sexual dysfunction among the 3617 men.
In the placebo group, impotence resolved in two men only after the study drug was stopped. In the simvastatin group, impotence resolved in 14 men despite continued simvastatin treatment. The difference of 28 cases versus 37 was not significant—Fisher’s exact test: P=0.32, Cox proportional hazards model: relative risk 1.30 (95% confidence interval 0.80 to 2.12), P=0.29. From these findings, it is unlikely that simvastatin causes impotence or sexual dysfunction.
Table.
Number of men in the Scandinavian simvastatin survival study spontaneously reporting temporary or permanent impotence or sexual dysfunction (placebo 1803, simvastatin 1814)
| Onset time (after randomisation) | Placebo
|
Simvastatin
|
|||
|---|---|---|---|---|---|
| Impotence | Resolved | Impotence | Resolved | ||
| <1 month | 3 | 2 | 0 | 0 | |
| 2-3 months | 2 | 0 | 6 | 2 | |
| 4-12 months | 2 | 1 | 5 | 4 | |
| Year 2 | 9 | 3 | 8 | 6 | |
| Year 3 | 4 | 0 | 4 | 0 | |
| Year 4 | 1 | 1 | 4 | 1 | |
| Year 5-6 | 7 | 1 | 10 | 1 | |
| Total | 28 | 8 | 37 | 14 | |
| Not resolved | 20 | 23 | |||
References
- 1.Jackson G. Simvastatin and impotence. BMJ. 1997;315:31a. [Google Scholar]
- 2.Scandinavian Simvastatin Survival Study Group. Randomized trial of cholesterol lowering in 4444 patients with coronary heart disease: the Scandinavian simvastatin survival study (4S) Lancet. 1994;344:1383–1389. [PubMed] [Google Scholar]