Pain management is a complex and challenging aspect of nursing care and in the case of individuals who are experiencing comorbid pain and substance use disorders (SUDs), the difficulties and complexities are much greater. The field of pain management has been continuously evolving over the past three decades, with the most significant trends in pain medicine comprising an increasing emphasis on aggressive treatment of acute and chronic pain with prescription opiate/opioid medications beginning in the mid-1990s and the subsequent opiate use epidemic that has evolved into the greatest public health crisis of the 21st century. The great emphasis placed on treating pain as the “fifth vital sign” that arose in the medical field in the late 1990s found support in JCAHO practice regulations (2001) that held hospitals accountable for pain control as a patient outcome. These trends in the pain management field were accompanied by a significant increase in opioid prescriptions, beginning with the marketing of oxycontin in 1996, and increasing steadily in the early 2000s (Centers for Disease Control and Prevention [CDC], 2011). The general consensus within the field of pain research saw prescription opioids as the “gold standard” treatment, first-line interventions for acute postsurgical pain as well as chronic cancer-related pain syndromes. During this time period, these painkillers were increasingly being employed as first-line pharmacologic treatment interventions for a myriad of chronic pain syndromes. Although the safety and efficacy of opioids in acute postsurgical and cancer pain were supported by a strong body of research, evidence for the safety and efficacy of opioid painkillers in the treatment of chronic noncancer pain was much more tenuous; this did not stop them from being widely marketed and prescribed to treat chronic pain. At this point, recognition of the increasing prevalence of addiction to prescription opiate/opioid painkillers that followed the increase in opioid prescriptions for chronic pain led some researchers and clinicians to begin to question the purported efficacy and safety of long-term opioid therapy
for chronic pain patients. A landmark investigation by the Centers for Disease Control and Prevention (CDC), released in 2011, demonstrated that there was a strong association between the increasing rates of opioid overdose mortality and prescription painkiller-related emergency department admissions, and the corresponding increase in opioid prescriptions between 1999 and 2008 (Figure 11-1). At this time, prescription drug overdoses had surpassed illicit (heroin and cocaine) drug overdoses as the primary cause of drug overdose death, which was then second only to motor vehicle accidents as the primary cause of accidental death in the United States (CDC, 2011). The intervening years have seen an increasing recognition within the pain treatment field of the dangerous addictive potential of prescription painkillers, and the accompanying changes in the availability of prescription opioids for misuse has seen a significant trend of individuals with established opioid use disorders transitioning to misusing heroin (which is cheaper and more readily available), with resulting increases in heroin overdose deaths. The adulteration of the street heroin supply with the powerful synthetic opioid fentanyl (25-40 times more potent than
heroin) has greatly increased opioid overdose mortality rates in the past few years so that drug overdose deaths (72 306 in 2017) have surpassed automobile accidents as the primary cause of accidental death in the country (National Center for Health Statistics, 2018). Opiate/opioids are involved in the majority of drug overdose deaths (49 068 in 2017), with the majority involving fentanyl-related fatalities (29 406 in 2017) (Figure 11-2). However, the ongoing contribution of prescription painkiller misuse to the opiate epidemic must not be underestimated as nearly 80% of Americans misusing heroin reported that they began their addiction using prescription painkillers (National Institute on Drug Abuse, National Institutes of Health, & U.S. Department of Health and Human Services, 2018).

SUDs, also referred to as addiction disease, are a class of neurobiologic syndromes that are characterized by continued compulsive use of a drug (such as alcohol, cocaine, or prescription opiate painkillers), despite negative consequences to health, psychological well-being, and social functioning. Many legal (alcohol, tobacco) and illegal (marijuana, heroin, cocaine) drugs have the capacity to produce a pleasurable state of intoxication that is highly reinforcing of continued drug use. The psychologically rewarding effects of certain drugs have led to their recreational use by diverse cultures throughout human history. A certain percentage of individuals who engage in recreational drug use will progress to active addiction, where drug use becomes compulsive and involuntary and drug taking is increasingly motivated by relief of dysphoria rather than for pleasurable or euphoric effects. The demographics
of addiction disease in recent years have demonstrated an alarming increase in the prevalence of misuse of prescription and illicit opiate narcotics that have reached epidemic proportions and comprise a key public health emergency of great relevance to the field of pain management in the United States and other western societies (Volkow, Benveniste, & McLellan, 2018).

Addiction disease, including opiate use disorders (OUDs), affects a large segment of the population. Knowledge about the biology, epidemiology, and treatment modalities for addiction disease is therefore vital for the advanced practice nurse, especially within the context of management of acute and chronic pain patients. The 2017 National Survey on Drug Use and Health (NSUDH) commissioned by the Substance Abuse and Mental Health Services Administration (SAMSHA) contains the most current population level data on the disease burden of addiction and psychiatric disease in the American population. According to the NSUDH, in 2017, approximately 30.5 million Americans engaged in illicit drug use during the previous month (11.2% of the adult population over the age of 12). For young adults aged 18 to 25, the rate was much higher (25%). Past year illicit opioid use, defined as any use of illicit opiates (heroin), or use of prescription opiate or opioid narcotics without a prescription or in larger amounts or longer time than prescribed, was reported for 11.4 million Americans, comprising 4.2% of all adults and 7.3% of all young adults in the U.S. population (Substance Abuse and Mental Health Services Administration [SAMSHA], 2018) (Figure 11-3). The incidence of new opioid misusers was also alarming, as 2 million individuals initiated prescription painkiller misuse and 81 000 initiated heroin use during the past year. In 2017, 19.7 million (7.2%) adults met the criteria for a diagnosis of an SUD; of these, 7.5 million met criteria for an SUD for illicit drugs (SAMSHA, 2018). Although the rates of misuse of alcohol and most
illicit drugs (with the exception of marijuana) have remained stable over the past two decades, there has been an epidemic increase in the rates of misuse of prescription and illicit opiate/opioid narcotics. Approximately 2.1 million adults met the criterion for an OUD in 2017, with 1.7 million having a prescription drug SUD and 700 000 having a heroin use disorder; the rate of OUDs in the young adult population is now 1.3% (SAMSHA, 2018). Of the 6 million Americans (2.2% of the adult population) engaging in past month prescription drug misuse, the majority (3.2 million or 1.2% of adults) misused painkillers (opiate/opioid drugs), whereas 1.7 million misused tranquilizers (benzodiazepines), 1.8 million misused stimulants, and approximately 350 000 misused sedative drugs (SAMSHA, 2018) (Figure 11-4). The misuse of benzodiazepines is a phenomenon of particular importance to pain clinicians, as benzodiazepine overdose deaths increased 8-fold between 2002 and 2016 and the majority of these deaths also involved opioids (National Center for Health Statistics, 2018). The phenomenon of coaddiction to opioids and benzodiazepines or other sedative drugs should be of great concern to nurses working in pain management and addiction, as these combinations greatly increase a person’s risk for a fatal drug overdose because of the synergistic effect on depression of the respiratory control centers in the central nervous system.

The high rate of SUDs is exacerbated by the insufficient treatment infrastructure for managing SUDs and comorbid psychiatric illnesses; of the 20.7 million Americans requiring treatment for SUDs in 2017, only 4 million (12.2%) received treatment. Even more alarming, of the 8.1 million Americans with an SUD and a comorbid psychiatric illness, only 8.3% received treatment for addiction and the comorbid mental illness and 49% received no treatment at all (SAMSHA, 2018). These data are concerning because an overwhelming body of research has demonstrated that addiction is a chronic, relapsing, degenerative neurobiologic disease that requires
ongoing treatment to preserve health and functional status and prevent relapse and death. The epidemiologic evidence has demonstrated that addiction disease is a common syndrome within the U.S. population and has shown that there is a high degree of overlap and comorbidity for addiction with chronic pain syndromes and many common psychiatric diseases (mood disorders, schizophrenia, attention deficit disorders). The presence of addiction disease within a patient being treated for a pain syndrome greatly complicates treatment for several reasons. The most obvious of these factors involves the addictive nature of the opiate/opioid analgesics that have traditionally been the primary pharmacologic treatment for both acute and chronic pain management. Careful attention in assessing and monitoring patients receiving pharmacologic treatments for pain management is a critical practice competency for nurse practitioners and advanced practice nurses. Patient assessment and risk stratification have been greatly assisted in recent years by the development of several screening instruments to measure addiction risk with opioid treatment. These instruments are summarized in the next section.

This section of the chapter will describe the different screening instruments that have been developed to aid clinicians in making decisions related to the utilization of opiate/opioid analgesics in the context of pain management. The Pain Medication Questionnaire (PMQ) is a brief 26-item (Likert scale) self-report screening instrument designed to assess the risk of opioid medication misuse in chronic pain patients. Patients respond to each question on a 5-point Likert scale from 0 (disagree) to 4 (agree). The PMQ is designed to measure chronic pain patients on a range of potential risk based on endorsement of behaviors and attitudes correlated with opioid misuse, which were identified through addiction literature and expert consensus (Holmes et al., 2006). Scores on the PMQ range from 0 to 104, with increasing scores associated with greater risk of medication misuse. The PMQ was validated in a sample (n = 271) of new chronic pain patients. Patients are stratified by risk according to their total scale score, with a score between 70 and 104 indicating “high risk” and a score of 0 to 34 indicating “low risk.” The original study showed that individuals in the “high risk PMQ” group were 2.6 times more likely to have a known substance use problem and 2.3 times more likely to drop out of treatment relative to individuals scoring in the “low risk PMQ” group (Holmes et al., 2006). Patients who completed the treatment period measured at 6 months after treatment completion were found to have significant decreases in their scores relative to patients who were unsuccessfully discharged from the pain management program or voluntarily dropped out (Holmes et al., 2006).

The Risk Index for Overdose or Serious Opioid-Induced Respiratory Depression (RIOSORD) is a brief inventory that is intended as a screening tool to estimate the likelihood of life-threatening respiratory depression
or overdose among medical users of prescription opioid painkillers. The RIOSORD was derived from a case-control analysis of healthcare data for 1 877 841 patients with an opioid prescription seen through the Veteran’s Health Administration from October 2010 to September 2012, which identified 817 cases of overdose or severe respiratory depression and used regression modeling to compare predictor risk variables with 8170 controls. Point values were assigned to each predictor variable and modeling of risk index scores was performed to calculate predicted probabilities of OSORD (Zedler et al., 2015). The analyses identified 15 predictor variables which correlated with increased risk of respiratory depression, which were retained in the final version of the RIOSORD. Each predictor was assigned a specific point value (with the total scale score ranging from 0 to 110), with increasing scores indicating greater risk of overdose or respiratory depression. Ten risk classes by deciles of predicted probability were identified. Average predicted probabilities for adverse events ranged from 3% for the first decile (scores 0-24) to 94% for the 10th decile (scores ≥67) and these predicted probabilities were very similar to the observed incidence rates of 3% through 86% across risk classes (model C-statistic = 0.88) (Hosmer-Lemeshow goodness-of-fit statistic = 10.8, P > 0.05). The RIOSORD is intended for use as a screening tool to assess patient’s baseline risk of opioid overdose or respiratory depression and can also be used at intervals during ongoing long-term opioid treatment and to reevaluate risk based on changes to patient clinical status or medication regimen.

The Current Opioid Misuse Measure (COMM) was created as a measure to assess chronic pain patients already receiving long-term opioid therapy for changes in health status over time (Butler et al., 2007). The COMM operationalizes changes in patient status through measurement of observable behaviors during a 30-day time period. The initial validation of the COMM scale was conducted in a sample (n = 227) receiving opioids for chronic noncancer pain. A 17-item version of the scale demonstrated adequate ability to measure aberrant drug-related behaviors and good internal consistency (α = 0.86) and test-retest reliability (ICC = 0.86; 95% CI: 0.77-0.92), and was retained. With a total scale score range of 0 to 68, a cutoff score of 9 yielded a sensitivity of 0.77 and specificity of 0.66 (Butler et al., 2007). A cross validation of the COMM scale in a sample (n = 226) of chronic noncancer pain patients produced comparable results (α = 0.83) (AUC = 0.79; SE = 0.31, 95% CI: 0.73-0.85, P = 0.001) (Butler, Budman, Fanciullo, & Jamison, 2010).

The Opioid Risk Tool (ORT) was created as a brief screening tool to predict aberrant drug-related behavior in chronic pain patients on long-term opioid therapy. The ORT measures risk factors, which were derived from the addiction research literature (personal/family history of SUDs, age, childhood sexual abuse history, and psychiatric diagnoses). Initial validation of the ORT was conducted in a sample (n = 185) of new pain clinic patients who received scores of 0 to 3 (low risk), 4 to 7 (moderate risk), or ≥8 (high risk) (Webster & Webster, 2005). The C-statistic (a measure of the sensitivity and specificity of the ORT screen) demonstrated good discrimination in both male (c = 0.83) and female (c = 0.85) patient models. The empirical validity of the ORT was also demonstrated, as 94.4% of individuals rated as “low risk” on the ORT did not display any aberrant drug behaviors, whereas
90.9% of “high risk” individuals had at least one aberrant drug-related behavior (Webster & Webster, 2005).