Opioids are a class of analgesics commonly employed in the treatment of acute and chronic pain conditions. [1] 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 the activation of 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.[1]

The use of opioids in the treatment of chronic non-cancer pain is a current area of controversy due to the potential risk of patients' physical dependence on opioid medications.[2][3][4] 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.[5][6]

Several tools have undergone development for assessing the risk of developing opioid use disorder. The Opioid Risk Tool (ORT) is a validated screening instrument that is 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.[7] 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.[8] The matter is much more complicated as a previous history of addiction from 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.[9] 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 16-45 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, and a score of 8 or greater suggests a high risk of future abusive drug-related behavior. There are several interactive versions of the ORT available online, which allow for quick calculation of a patient's risk according to the ORT.

Recently, Cheatle et al., have 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.[7]

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 prior to initiation of long-term opioid therapy;[10] 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).[11][12][13][14]  

Over the past several decades, there has been a significant increase in opioid use, misuse, and abuse, although the phenomenon seems to be dramatic, especially in some geographical areas, while in others such as Europe, the consumption and misuse or abuse of opioids is less alarming. This upward trend in opioid use started in the 1990s, especially in the United States, which is the largest consumer of opioid drugs in the world, accounting for close to 80% of the opioids produced worldwide. Prescription opioids are now the leading drug of abuse, and their use can produce both medical and psychological side effects. Opioid overdose, indeed, is the most common cause of accidental death among young adults. As of 2018, predictions suggest that over the next decade, there could be close to 500000 opioid-related deaths in the United States. The effects of the misuse of opioids are manifold. In the surgical setting, for instance, opioid misuse is associated with increased risk of postoperative complications, postoperative death, as well as falls and fractures in the elderly.[8][15][16][17][18]

Early identification of at-risk patients is an effective strategy in preventing aberrant opioid behavior. In the postsurgical setting, opioid abuse increases risks of poor surgical outcomes, motor vehicle accidents, myocardial infarction, bone fractures, and death, among a variety of other medical issues. Opioid-related adverse events have a direct positive correlation with the opioid dosages. Although the CDC has indicated there is insufficient evidence to determine the utility of opioid risk screening tools, some prescription guidelines suggest the use of these instruments. In this context, the ORT has been adopted in clinical practice to evaluate the risk of future aberrant opioid behavior.[8] Indeed, the ORT is better for low-risk screening, and it may be more useful in large-volume medical practices due to its relative ease of use.[15] Furthermore, the tool is easy to perform as administration and scoring take less than 1 minute. Concerning the clinical significance of ORT, although opioid use should not be stigmatized simply because a patient is considered "high risk" by the ORT, these patients should be treated with other modalities of pain control, such as non-invasive or minimally invasive treatments.

For patients with an established treatment plan involving opioid therapy, frequent follow-up is highly essential for all patients, no matter their risk stratification. Higher risk patients require more frequent monitoring than lower-risk patients. Follow-ups may include re-screening of risk, urine drug screening, and observation for other clues of drug abuse. These clues may consist of requests for dose escalation, doctor shopping, forging prescriptions, requesting early prescriptions, unscheduled clinic visits, or emergency room visits with complaints of pain. Urine drug screening may identify illicit substances or non-use of prescribed medication. It is strongly recommended to collect a baseline urine drug screen to identify pre-existent drug abuse when present. These recommendations should involve interdisciplinary cooperation of physicians, nurses, technicians to improve patient outcomes.[15] [Level 2]