Nonarteritic Anterior Ischemic Optic Neuropathy In Men Using Sildenafil Citrate For Erectile Dysfunction: A Review Of >44,800 Patients In Clinical And

Main Category: Erectile Dysfunction / Premature Ejaculation
Also Included In: Urology / Nephrology
Article Date: 04 Nov 2006 - 0:00 PST

email to a friend   printer friendly   opinions  

UroToday.com - NAION is the acronym for Non-arteritic Anterior Ischemic Optic Neuropathy. The most common form of acute optic neuropathy in adults over 50 years of age, NAION is due to ischemia of the optic nerve.

Recent scattered case reports in the ophthalmologic literature have suggested that NAION may be caused by phosphodiesterase Type 5 inhibitors (PDE5i's) such as sildenafil.

This study reported at the 2006 meeting of the American Urological Association investigated the incidence of NAION in men who are users of sildenafil from three sources of epidemiologic data: the 103 international clinical trials of sildenafil conducted by Pfizer which yielded data on more than 13,400 men and more than 13,000 patient-years of observation; the International Men's Health Study (IMHS) conducted in four European countries which yielded data on more than 3800 men and more than 2900 patient years of observation; and the sildenafil Prescription Event Monitoring (PEM) study conducted in the United Kingdom which yielded data on more than 28,000 men and more than 35,500 patient-years of observation.

No cases of NAION were observed in the sildenafil clinical trials or in the IMHS. One case of NAION occurred in the PEM study. Taking all three sources together, the unadjusted incidence rate of NAION was 2.8 cases per 100,000 patient-years. Previous epidemiologic studies have identified the annual incidence of NAION in the general population to be 2.5-11.8 cases per 100,000 men over the age of 50 years. The authors concluded that the incidence of NAION in carefully-monitored men using sildenafil is not greater than the expected incidence of NAION in the general population.

Editor's Note:
This study strongly suggests that sildenafil is not a risk for NAION. A recent editorial in the Archives of Ophthalmology written by three prominent ophthalmologists, including one who has authored several of the case reports of NAION in sildenafil users, opines that the only men who need to avoid sildenafil for visual reasons are those with a previous history of NAION (1). From this study presented to the 2006 American Urologic Association and the editorial in the Archives of Ophthalmology, it seems reasonable to conclude that for men without a history of any form of blindness, PDE5 inhibitor therapy for erectile dysfunction continues to be an appropriate treatment

1. Fraunfelder FW et al. Non-arteritic anterior ischemic optic neuropathy and sildenafil. Arch Ophthalmol 124: 733-4, 2006.

AUA 2006 - Abstract 697: Sobel RE, et al.

Reviewed by UroToday.com Contributing Editor Ira Sharlip, MD

UroToday - the only urology website with original content written by global urology key opinion leaders actively engaged in clinical practice.

To access the latest urology news releases from UroToday, go to:
www.urotoday.com

Copyright © 2006 - UroToday

• Additional
• References
• Citations