Opioids are a class of analgesics commonly employed in the treatment of acute and chronic pain conditions.  Apart from the analgesic effects, the opioids used in clinical practice may interfere with different physiological functions, including stress, temperature, respiration, endocrine activity, gastrointestinal activity, memory, mood, and motivation. These opioid-induced effects are produced by activating opioid receptors located in the central and peripheral nervous systems. These opioid receptors are an extensive family of receptors, including the Mu OPiate receptors (MOP, also indicated as MOR), the Delta OPiate receptors (DOPs or DORs), Kappa OPiate receptors (KOPs or KORs), and Nociceptin OPiate receptors (NOPs or NORs) also known as opioid-receptor-like receptor 1 (ORL1). Moreover, other opioid receptors such as the zeta, the epsilon, the lambda, and the iota opioid receptors have also been characterized.
The use of opioids in treating chronic non-cancer pain is a current area of controversy due to the potential risk of patients' physical dependence on opioid medications. However, the alarming data about the deleterious effects of the misuse or abuse of opioids (opioid crisis) seems to have a geographical contextualization, being especially evident in North America and Canada, while in Europe, the problem appears to be less apparent.
Several tools have undergone development for assessing the risk of developing opioid use disorder. The Opioid Risk Tool (ORT) is a validated screening instrument commonly used in practice to evaluate the risk of future aberrant opioid use among chronic nonmalignant pain patients who receive prescribed opioids for pain relief. In other words, the tool quantifies the risk of developing an opioid use disorder (OUD). The assumption is that there would be predisposing factors, including behavioral factors and factors strictly related to the patient's history and experiences. For instance, opioid-related aberrant behaviors include abuse, misuse, and diversion. The matter is much more complicated as a previous history of addiction to opioids, or other substances is not the only predictive factor. In clinic practice, it is possible to note that many subjects with chronic pain syndromes that develop OUD do not have a prior history of addiction.
Webster et al. developed the ORT questionnaire., in 2005, as a self-performed screening tool designed for use by adult patients in primary care settings before beginning opioid treatment for pain management. It consists of ten scorable components. For some items, a different score is assigned depending on gender. The questionnaire asks patients to report on:
- Family history of substance abuse including alcohol (Female=1; Male=3), illegal drugs (2;3), and/or prescription drugs (4;4)
- Personal history of substance abuse including alcohol (Female=3; Male=3), illegal drugs (4;4), and/or prescription drugs (5;5)
- Whether the patient age range is between 16 to 45 years (1;1)
- A history of preadolescent sexual abuse (3;0)
- Psychological disease including attention deficit hyperactivity disorder (ADHD), obsessive-compulsive disorder (OCD), bipolar disorder, schizophrenia (2;2); and/or depression (1;1)
Scores are summed, and a score of 3 or below suggests a low risk for future opioid abuse, while a score of 4 to 7 indicates moderate risk. A score of 8 or greater suggests a high risk of future abusive drug-related behavior. According to the ORT, there are several interactive versions of the ORT available online, which allow for quick calculation of a patient's risk.
Cheatle et al. have recently developed and validated a weighted ORT eliminating the gender-specific history of preadolescent sexual abuse. Of note, they found that this revised ORT was able to better predict the development of OUD in individuals with chronic nonmalignant pain on long-term opioid therapy.
Other opioid risk screening tools include the Screener and Opioid Assessment for Patients with Pain Revised (SOAPP-R), developed to predict aberrant drug-related behaviors before initiation of long-term opioid therapy; the Diagnosis Intractability Risk Efficacy (DIRE) tool, the 17-item Current Opioid Misuse Measure (COMM) and its 9-item brief version, the 26-question Patient Medication Questionnaire (PMQ).