Monitoring opioid adherence in chronic pain patients: Assessment of risk of substance misuse

Background: Use of opioids for chronic non-cancer pain (CNCP) has increased in recent years because this pain had been undertreated. There was also a simultaneous increase in misuse and abuse of opioids. Deaths due to such abuse and misuse also have risen as seen in the many reports published every day in local papers as well as in the medical literature. So, it is imperative that patients who are prescribed these medications be monitored for adherence so misuse and abuse can be curtailed and opioids are available to those who genuinely need them for chronic pain control. There are various screening tools available to monitor such adherence, and there is an abundance of literature about it in addiction and psychiatric medicine. There is, though, a paucity of such literature as applied to pain medicine. Objectives: Our objectives for this review were twofold. We wanted to identify which screening tools are available to monitor opioid adherence and we wanted to see if there were prospective comparative studies of these tools to identify a single best tool that can be applied to all chronic non-cancer pain patients managed with opioids. Study Design: We did a review of the current literature about monitoring of opioid adherence. We also looked at their use, validity, and comparative studies. Methods: We performed a literature search using PubMed, EMBASE, and the Cochrane library. The search was conducted using the terms opioids, non-cancer pain, monitoring, and adherence. The databases from 1996 to November 2010 were reviewed. The search included prospective and retrospective studies, review articles, and FDA records. Bibliographies and cross references were reviewed when deemed appropriate. Conclusion: We found 52 publications, of which 22 met the criteria to be included in this manuscript. We found only one study that was prospective, and compared the various screening tools that are available to monitor opioid adherence. In the majority of the studies the number treated was small. There was not a single screening tool that can be applied universally to all patients who are on opioid therapy for chronic non-cancer pain.