Erectile dysfunction (ED) among men in agonist opioid treatment (AOT) programmes

Background: Agonist opioid treatment (AOT) with full and partial agonists of opioid receptors should be considered one of the key forms of treatment for heroin and other opioid addictions. Sexual dysfunction is a common side-effect of opioids. Symptoms of erectile dysfunction (ED) among patients enrolled in a variety of AOT programmes has been reported. The prevalence of ED has, however, so far never been reviewed separately or systematically. Aim: The main purpose of the present study is to review the existing literature according to the criterion of the prevalence of ED among patients receiving AOT medications for opioid addiction (methadone, buprenorphine, S-R morphine). Methods: A comprehensive computer literature search conducted on studies published from 2000 to April 2016 regarding ED among patients treated in AOT programmes for opioid addiction was performed by searching through the databases PubMed and Web of Science. Following the protocol, one preliminary screening operation was to divide the papers into two main clusters according to assessment of sexual dysfunction, with the first exploring the prevalence of ED and the second dedicated to other topics. At that point, all the studies not directly exploring the prevalence of ED were excluded. Results: A total of 131 records were screened, among them 18 studies with prevalence rates for ED between 12% and 93% (more exactly, 13% to 93% for methadone and 12% to 43% for buprenorphine). However, the methodological approaches adopted were highly variable, and included the use of methadone or buprenorphine, while excluding S-R morphine. Conclusions: ED is a common sexual dysfunction among men receiving AOT medication for opioid addiction, and it seems that condition is more frequent among patients treated with methadone than among those treated with buprenorphine. Further comparative studies are needed, especially those involving slow-release morphine.