Login to Access Video or Poster Abstract: MP09-17
Sources of Funding: This study was funded by a grant (5R21DK100820-02) from the United States National Institutes of Health (NIH) / National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)

Introduction

5-alpha reductase inhibitors (5ARIs) have been reported to increase the risk of erectile dysfunction (ED) in patients treated for benign prostatic hyperplasia (BPH); however BPH itself is an ED risk factor (potential confounding by indication). We conducted a cohort study with nested case-control analyses using the United Kingdom's Clinical Practice Research Datalink to estimate the risk of ED in men who used 5ARIs for the treatment of BPH.

Methods

We identified men aged 40+ with BPH who received at least one prescription for a 5ARI (finasteride or dutasteride), alpha blocker (AB), or both. Exposures were classified as 5ARI only, 5ARI+AB, and AB only. Cases were men who had a first ED diagnosis or treatment (surgery or phosphodiesterase type-5 inhibitor prescription) during follow-up. We calculated incidence rates (IRs) and adjusted incidence rate ratios (IRRs) with 95% confidence intervals (CIs). We also conducted a nested case-control analysis to control for major confounders and calculated adjusted odds ratios (ORs) with 95%CIs.

Results

We identified 71,849 men, among whom 5,814 were identified as new cases of ED over the 20 year study period (1992-2011). The incidence rate of ED was lowest among users of 5ARI only (15.3 per 1000 person-years) and similar among users of 5ARI+AB (19.2 per 1000 person-years) and AB only (20.1 per 1000 person years). The risk of ED was not elevated with use of 5ARI only (IRR=0.92, 95%CI 0.85-0.99) or 5ARI+AB (IRR=1.09, 95%CI 0.99-1.21) in comparison with AB only. In the nested case-control analysis, ORs were 0.94 (95%CI 0.85-1.03) for 5ARI only and 0.92 (95%CI 0.80-1.06) for 5ARI+AB, compared to AB only, and remained null regardless of number of prescriptions or exposure timing. The risk of ED increased with longer duration of BPH, independent of exposure.

Conclusions

In a large, 20 year, real world observational study, 5ARI therapy for BPH does not significantly increase the risk of clinically meaningful incident ED compared to AB treatment. Risk of ED increased with longer duration of BPH.

Funding

This study was funded by a grant (5R21DK100820-02) from the United States National Institutes of Health (NIH) / National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)