Precision DDI™ & Drug Testing A Clinical Decision Support System PrecisionDDI™ & Drug Testing A Clinical Decision Support System Managing Editors Jack Kain, PharmD Clinical Toxicologist Precision Diagnostics San Diego, California Kevin Krock, PhD Director of Research & Development Precision Diagnostics San Diego, California 2 | precision diagnostics Table of Contents Introduction................................................................................................................................................. 4 Chapter 2: Understanding the Mechanisms Underlying Addiction............................................................6 Chapter 3: The Clinical Pharmacology of DDIs...........................................................................................7 Chapter 4: Epidemiology & The Economic Burden of Overdose Syndromes...........................................15 Chapter 5: Drug Testing & Clinical Decision Support Tools: A Clinical Decision Support System.........22 Chapter 6: Transition of Care & Actionable Interventions........................................................................23 Conclusion.................................................................................................................................................25 | 3 Introduction Precision DDITM is an integrated clinical decision support tool that provides clinicians with additional insights into risky drug combinations which are detected in patient urine and oral fluid specimens. Precision DDITM provides referenced drug information which describes administration, adverse reactions, contraindications, dosing, mechanism of action and the pharmacokinetics of a particular medication. Precision DDITM promotes better patient outcomes by opening up a new level of dialogue between clinicians and their patients in order to decrease the illicit utilization of life threatening drug combinations. This module focuses on the pharmacology of DDIs, the incidences of potential DDIs which can occur in pain management, family medicine, addiction and behavioral health specialties. It also captures the costs incurred on the health system as DDIs or dangerous drug combinations are manifested into overdose syndromes. Drug-drug interactions (DDIs) are a notable type of adverse drug event that affect millions of patients each year and are estimated to cause up to 5% of hospital admissions.1 A DDI has the ability to modify the action or effect of another drug administered successively or simultaneously.2 Effective clinical practices, particularly addiction treatment and pain management, should include the knowledge of potential DDIs and methods to lessen or mitigate their occurrences. Chronic co-prescribing of multiple drugs, or polypharmacy, often happens when a patient has several conditions and/or chronic disease states. A very common consequence of polypharmacy is the increased propensity for DDIs.2 4 | precision diagnostics In a study of chronic low back In a study of chronic low back pain, patients on long- term opioid analgesics, an overall reported prevalence pain, patients on long-term opioid of DDIs was 27 %.1 In relation to patients who are being treated for addiction or substance use disorder, analgesics, an overall reported these patients are more likely to be polydrug users prevalence of DDIs was 27%. which increases the potential for DDIs by adding three potential groups of drugs into the mix: 1) illicit drugs, 2) misused prescription drugs and 3) emerging psychoactive substances. Many patients with substance use disorders also manifest one or more co-occurring psychiatric disorders, making them more likely to be prescribed psychiatric medications. This increases the risk of DDIs between the substances of abuse and prescribed psychiatric medications. In pain management, review of clinical evidence noted by the Centers for Disease Control (CDC) found that currently available risk stratification tools (Opioid Risk Tool, Screener and Opioid Assessment for Patients with Pain Version, SOAPP-R and Brief Risk Interview) show insufficient accuracy for the classification of patients as being at low or high risk for abuse or misuse.3 Insufficient accuracy in risk stratification has led to a failure in identify underlying substance use disorders that predispose patients to adverse drug reactions such as DDIs. The CDC recently noted clinicians should utilize prescription drug monitoring program (PDMP) data and drug testing as appropriate to assess for concurrent substance use which might place pain patients at higher risk for opioid use disorder and overdose. Clinicians should provide counseling on increased risks for overdose and opioid use disorder when opioids are combined with alcohol or other drugs (benzodiazepines), thereby increasing the risk for DDIs.3 Table 1: 2016 CDC Guideline for Prescribing Opioids for Chronic Pain: Recommendations 9-11 3 Recommendation 9: Clinicians should review the patient’s history of controlled substance prescriptions using state prescription drug monitoring program (PDMP) data to determine whether the patient is receiving opioid dosages or dangerous drug combinations that put him or her at high risk. Recommendation 10: When prescribing opioids for chronic pain, clinicians should use urine drug testing before starting opioid therapy and consider at least annually to assess for prescribed medication as well as other controlled prescription drug and illicit drugs. Recommendation 11: Clinicians should avoid prescribing opioid pain medication and benzodiazepines concurrently whenever possible. Urine drug testing can provide information about drug use not reported by the patient. This can allow for the identification of deleterious drug combinations which are largely correlated with causing overdose syndromes. The The CDC has articulated that CDC recommends clinicians use unexpected results to take steps to improve patient safety (change in pain management clinicians should communicate strategy, tapering or discontinuation of opioids, more frequent to their patients that urine drug re-evaluation, offering naloxone or referral for treatment of substance use disorder.3 The CDC has articulated that testing is intended to improve clinicians should communicate to their patients that urine their safety. | 5 drug testing is intended to improve their safety.3 It is recommended that clinicians who consider opioid therapy for chronic pain in patients with drug or alcohol disorders should incorporate strategies which mitigate risk, such as offering naloxone and increasing monitoring. As long as those patients are not diagnosed with active cancer and are not receiving palliative or end-of-life care.3 Chapter 2: Understanding the Mechanisms Underlying Addiction Substance use disorders are “a cluster of cognitive, behavioral and physiological symptoms indicating an individual continues using the substance despite significant substance related problems.”4 A substance use disorder is further defined by compulsive patterns of behavior, impairment in social & occupational settings & functions and recurrent use despite exacerbation of physical and psychiatric issues. Treatment plans should include a multifaceted approach which incorporate counseling, educational programs & software and medication assisted treatment. According to the DSM-5 criteria, substance use disorders can be stratified into different levels of severity (mild, moderate and severe). A patient must manifest a minimum of 2 criteria to be diagnosed with a clinically meaningful substance use disorder as displayed in Table 2.4 Table 2: DSM-5 Diagnostic Criteria for Substance Use Disorders4 1. Substance is taken in larger amounts or over a longer period than was intended. 2. Unsuccessful efforts to cut down or control substance use. 3. A great deal of time spent in activities necessary to obtain the substance, use it or recover from the substance’s effects. 4. Craving, or a strong desire or urge, to use the substance. 5. Recurrent substance use resulting in a failure to fulfill major role obligations at work, school or home. 6. Continued substance use despite having persistent or recurrent social or interpersonal problems caused or exacerbated by the effects of the substance. 6 | precision diagnostics 7. Important social, occupational or recreational activities are given up or reduced because of substance use. 8. Recurrent substance use in situations in which it is physically hazardous. 9. Substance use is continued despite knowledge of having persistent or recurrent physical or psychological problems that are likely to have been caused or exacerbated by the substance. 10. Tolerance. 11. Withdrawal. Severity: Mild (2-3 symptoms); Moderate (4-5 symptoms); Severe (6 or more symptoms) Pattern of substance use leading to clinically significant impairment or distress, as manifested by at least 2 of the following within a 12-month period. Advances in neuroimaging have enabled Figure 1: The Reward System clinicians to observe changes within the brain which occur as a result of the repeated use of substances. Just as diabetes affects the pancreas, addiction affects the brain’s structure and function, causing it to associate compulsive behaviors with pleasure. Addictive substances cause a surge of dopamine in the brain’s reward system (nucleus accumbens), leading to a feeling of euphoria which encourages the brain to seek out the drug again.5,6 See Figure 1. Ordinarily, we must put in time and effort to achieve joy or ecstasy, psychoactive substances provide a potent