Can simvastatin improve erectile function and health-related quality of life in men aged ≥40 years with erectile dysfunction? Results of the Erectile Dysfunction and Statins Trial [ISRCTN66772971]
Correspondence: Dr Daksha Trivedi, University of Hertfordshire – Centre for Research in Primary and Community Care, College Lane Hatfield AL10 9AB, UK.
What's known on the subject? and What does the study add?
- Erectile dysfunction (ED) is often associated with endothelial dysfunction. It is also recognized as a marker for underlying vascular disease. There are missed opportunities to address cardiovascular risk factors in these men.
- Simvastatin administered for 6 months improves sexual health-related quality of life in men aged ≥40 years with untreated ED. It reduces the risk of future cardiovascular events via a reduction in serum cholesterol in men with ED. A non-significant trend towards improving erectile function suggests longer trials with a more potent statin may be required. There is high probability (>80%) of simvastatin being cost-effective in men with ED. Enquiry about erectile function provides the opportunity to address cardiovascular risk factors.
- To evaluate the effectiveness and cost-effectiveness of simvastatin on erectile function and health-related quality of life in men aged ≥40 years with erectile dysfunction (ED).
Patients and Methods
- ED is common in men aged ≥40 years and impacts upon their overall health-related quality of life and that of their partners.
- Men aged ≥40 years who were not receiving lipid lowering or anti-hypertensive medication and not at high cardiovascular risk were recruited from 10 general practices in the East of England.
- In total, 173 eligible men with untreated ED were randomized to double-blind treatment with 40 mg of simvastatin or placebo once daily for 6 months. Data were collected at three points over 30 weeks.
- The main outcome was erectile function (International Index of Erectile Function-5 score). Secondary outcomes included male ED-specific quality of life (MED-QoL), quality-adjusted life years (QALYs) using the generic Euroqol measure (EQ-5D), endothelial function, cardiovascular risk, cholesterol and health service costs.
- There was no significant difference in erectile function between the simvastatin and placebo groups (mean change, 1.28 vs 0.07, z = 1.1, p = 0.27), although a significant improvement in MED-QoL was observed (5% vs 2%, z = 2.09, p = 0.04).
- Both 10-year cardiovascular risk and low-density lipoprotein were reduced (cardiovascular risk, z = −3.67, p < 0.001; low-density lipoprotein, z = −5.46, p < 0.001), with no consistent change in endothelial function.
- The frequency of sexual encounters is correlated with improved erectile function.
- The joint distribution of costs and QALY benefits indicates that the probability of simvastatin being cost-effective for willingness-to-pay thresholds of £20 000 and £30 000 is 86% and 83%, respectively.
- Identifying men with ED provides an opportunity to modify future cardiovascular risk and to improve MED-QoL by treating them with 40 mg of simvastatin.
- The joint analysis of costs and QALY benefits suggests that there is high probability that simvastatin is a cost-effective strategy in men with ED.
- The findings could influence urological and primary care practice by including questions on ED during routine consultations and relevant clinical protocols. This provides an opportunity to impart lifestyle advice.