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1 A Review of Evidence-Pain Management and Therapeutic Options to Prevent Opioid Addiction Graves T. Owen, MD Chairman of the Board Texas Pain Foundation Conflicts of Interests: None 1

2 Chronic Pain Assessment Obtain all pertinent previous medical records (Chain of Custody) Perform detailed pertinent history of pain, mental health, and substances use history PE to include posture, gait, orthopedic, and neurologic exams. Discuss realistic expectations Exhaust evidence-based conservative care prior to non-evidencebased high risk treatments What is Pain? What is Suffering? Pain is defined as an unpleasant sensory and emotional experience with actual or potential tissue damage or described in terms of such damage. The International Association for the Study of Pain (IASP) Pain.is always a psychological state. AMA Guides to the Evaluation of Disease and Injury Causation, Second Edition Page 389 Suffering is one s inability to cope with adversity. 2

3 How to assess pain? Primary assessment is by functional changes as a result of pain. Function is more objective and reproducible. The 0-10 VAS scale is actually assessing suffering rather than pain (a complex interaction of physical and psychosocial conditions). Treating function rather than pain will result in better outcomes and minimize risk of over-/under-treatment. Chronic Pain vs. Chronic Pain Syndrome Chronic benign pain is pain that persists after tissue healing (3 to 6 months). This is not a lecture on cancer pain. Neuropathic Pain may have ongoing tissue destruction if offending agent persists (alcohol, elevated glucose, toxin exposure). Chronic Pain Syndrome is someone with chronic pain who is unable to function. 3

4 Disability Objective finding of serious emotional distress is seen more commonly in subjects without serious pathology. That is, patient with serious spinal pathology such as chronic vertebral osteomyelitis or unstable spondylolisthesis have shown less emotional distress despite severe pain than subjects with non-specific LBP illness. Carragee EJ and Hannibal M. Diagnostic evaluation of low back pain. Orthop Clin N Am. 2004;35:7-16. Disability (cont.) The most helpful components for predicting persistent disabling low back pain were maladaptive pain coping behaviors, nonorganic signs, functional impairment, general health status, and presence of psychiatric comorbidities. Chou R and Skekelle P. Will This Patient Develop Persistent Disabling Low Back Pain? JAMA. 2010;303(13):

5 Chronic Disabling LBP No studies found any physical factor that can reliably predict which patient with back pain will go on to develop chronic disabling low back pain. The single best predictor were psychiatric comorbidities. AMA Guides to the Evaluation of Disease and Injury Causation, Second Edition page 228. Published Disability Perception Disability perception has never correlated well with physical pathology. Strongly correlates with unstable psychosocial issues. Therefore, severe pain intensity (suffering) and disability perception indicates unstable psychosocial issues until proven otherwise. 5

6 Emotional Distress objective finding of serious emotional distress is seen more commonly in subjects without serious pathology. That is, patient with serious spinal pathology such as chronic vertebral osteomyelitis or unstable spondylolisthesis have shown less emotional distress despite severe pain than subjects with non-specific LBP illness. Carragee EJ and Hannibal M. Diagnostic evaluation of low back pain. Orthop Clin N Am. 2004;35:7-16. Incidence of Psychosocial Comorbidities Chronic pain syndrome 80% depressed 70% anxiety/panic attacks 30-60% personality disorders >25% incidence of addiction 10% qualify as psychogenic pain Majority with maladaptive coping strategies Manchikanti et al. Pain Physician

7 Chronic Pain and Suicides The incidence of suicides in the chronic pain population equals the general population if psychiatric comorbidities are taken into account. Recognize and appropriately treat psychosocial comorbidities in the chronic pain population. Psychosocial Comorbidities Physicians commonly underestimate the degree of psychosocial comorbidities found in their pain patients unless psychometric testing is performed. Daubs, et al. J Bone Joint Surg AM

8 Maladaptive Coping Mechanisms Lack of Acceptance (inability to accept pain) Fear Avoidance Catastrophization Injustice (includes victimization and entitlement) Disability Conviction (black and white thinking) All based on foundation of cognitive distortions A form of distorted thinking that aggravates pain. Black & white thinking, overgeneralization, mental filtering, discounting the positive, jumping to conclusions, magnification, emotional reasoning, should statements, personalization/blaming 8

9 Risk Factors for Developing Disabling Chronic Pain Maladaptive Coping Behaviors Nonorganic Signs Functional Impairment General Health Status Psychiatric Comorbidities Chou JAMA 2013 Mechanisms of Action in Chronic Pain 1. Traditional Medical Model Assumes that pain is caused by a peripheral pain generator. Results in chasing numerous theoretical pain generators. Failure to find and cure a pain generator leads to further patient frustration. Treatments are passive and do not require patient participation. 2. Neuroplasticity 9

10 Neuroplasticity Insult results in maladaptive neurological changes that include: Axonal sprouting Production of new receptors and transmitters that are abnormal for that nerve cells usual function. Abnormal regulation by third party players such as glial cells Outdated Concepts DDD More current research, primarily studies of twins, suggests that physical loading specific to occupation and sports plays a relative minor role in disc degeneration. Disc degeneration is now considered a condition that is determined largely by genetics. Discogenic Pain Symptoms consistent with non-specific low back pain have not, to date, been shown to correlate with specific anatomic changes consistent with tissue damage on imaging or physical examination. AMA Guides to the Evaluation of Disease and Injury Causation, Second Edition 10

11 Ethics Beneficence: Defined as action(s) done for the benefit of others. Beneficence actions taken to prevent or remove harms or to simply improve the situation. Nonmaleficence: Defined as to do no harm. Physicians must refrain from providing ineffective treatments or acting with malice toward patients. Standard of Care The standard of care is what a reasonable and prudent physician does in the same or similar clinical situation. A reasonable and prudent physician will look to the evidence based literature for a foundation of knowledge. A reasonable and prudent physician exhausts conservative evidence based treatments prior treatment with higher risk and lower evidence treatments (First do no harm). Failure to exhaust conservative evidence based treatments prior to higher risk or non-evidence based treatments is both a breach in the SOC and unethical. A reasonable and prudent physician uses sound medical judgment. 11

12 Treatment Options Rehabilitation Cognitive behavioral therapy (CBT) Physical Therapy, Occupational Therapy, Yoga, Tai Chi Compliance is often low without psychosocial support Pharmaceutical NSAIDs Neuromembrane Stabilizers (TCA, gabapentin, pregabalin, etc) Note that TCA and gabapentin are off label. Topical (lidocaine gels)?opioids Interventional Spinal Cord Stimulators, Injections ACP Guides Recommends Non-pharmaceutical Treatments as 1 st line Physical Modalities: Exercise (any exercise is helpful): strong evidence for relief and prevention of spine injuries Tai Chi: Systematic reviews and meta-analysis supported Yoga: Systematic reviews and meta-analysis supported 12

13 ACP Guides (cont.) Psychological Modalities: CBT ACT Mindfulness-Based Stress Reduction Biofeedback Self-Efficacy, construct based on Social Cognitive Theory Multidisciplinary/Interdisciplinary Rehabilitation Extensive literature supports efficacy and cost effectiveness Complementary Treatments ACP Guides (cont.) Acupuncture: Numerous large meta-analysis with long-term F/U Massage: 60 high quality studies Spinal Manipulation: Numerous meta-analysis show efficacy and cost effectiveness. 13

14 How CBT/Exercise Helps CBT and exercise rewires the nervous system. Exercise promotes endorphins and positive mood changes. Exercise prevents or minimizes functional loss. Cognitive Behavioral Therapy and exercise are evidence based conservative treatments (first line therapy). NSAIDs Inconsistent evidence for pain. Several RCT no better than placebo. Two types: Selective and Non-selective Cox-2 inhibitors Selective have lower incidence of GI symptoms but GI bleed rate is similar to non-selective Cox-2 inhibitors. No benefit from acetaminophen NNT=2.9 for non-neuropathic pain. 14

15 Pharmaceutical Treatments Concepts: Number Needed to Treat (NNT) Defined as number of patients that must be treated with a given pharmaceutical agent to obtain one positive response (typically defined as a 50% reduction in pain). Number Needed to Harm (NNH) Defined as number of patients that must treated with a given pharmaceutical agent to obtain one harmful response (typically a significant adverse side effect). Tricyclic Antidepressants Neuropathic Pain (off label use): Considered first line treatment Supported by both meta analysis and systematic reviews Evidence of effectiveness in post-cva pain, PHN, painful neuropathies, and postmastectomy. NNT=3 NNH=14 Negative results in spinal cord pain, phantom limb pain (possible poor study design), HIV neuropathy, cisplatinum neuropathy, neuropathic cancer pain, and chronic root pain. SE: Contraindicated with cardiac arrthymias or epilepsy (baseline EKG recommended) Narrow therapeutic window and low threshold for toxicity (checking blood levels recommended). Dry mouth, constipation, sweating, dizziness, orthostatic hypotension, urinary retention 15

16 Neuromembrane Stabilizers SNRI: Duloxetine (Cymbalta)/milnacipran (Savella); Approved for painful DM neuropathy, fibromyalgia, depression, anxiety (Cymbalta only), chronic musculoskeletal pain (Cymbalta only). Cymbalta NNT: DM=6, OA=7, Fibro=6-8 Savella NNT: Fibro=12. Venlafaxine (Effexor): Off label for pain. Generally not supported by studies. Anticonvulsants: Pregabalin (Lyrica); Approved fibromyalgia and painful DM neuropathy. NNT: DM=4 Fibro=12 Gabapentin (Neurontin); Off label but supported by several studies. Drug of abuse! Topiramate (Topamax); generally used for HA prophylaxis. Cognitive impairment worst SE. Topical Agents Lidocaine Patch/Gels/Creams: Lidoderm Patch;Approved for PHN No pharmaceutical rationale for pain deeper than the surface of the skin as lidocaine is rapidly metabolized by plasma cholinesterase. Very expensive placebo for LBP. Topical NSAID; No evidence for neuropathic pain. Compounded Topical Creams; No evidence that most of these drugs can penetrate the skin. No rationale that topical is better than oral. Not supported. Very big business. Expensive placebo. 16

17 Opioids Risk factors for aberrant drug taking behaviors. Family or personal history of ETOH or drug addiction. Nicotine dependency Depression and/or anxiety Impulse control problems (ADD, OCD, bipolar, schizophrenia, personality disorders) Hypervigilant state (PTSD, abuse history) Somatoform disorders Multisite pain (> 3 body parts) Age Opioids (cont.) No long term efficacy studies for chronic opioid therapy (COT). Known risk of abuse. Risk outweighs any known benefit. Several observational and epidemiological studies suggest majority of people treated with COT have a functional decline. Thus, non-evidence based high risk treatment. Unstable psychosocial issues are relative contraindication to use of opioids. Unstable psychosocial issues are common. 17

18 Opioids (cont.) Recent VA study compared opioids to non-opioids treatments in randomized study of 1 year duration. No difference in efficacy. Opioids had more side effects. Krebs et al. Effect of Opioids vs Nonopioid Medications on Pain- Related Function with Chronic Back Pain or Hip or Knee Osteoarthritis. The SPACE Randomized Clinical Trial. JAMA. 2018;319(9): Opioids (cont.) There is no safe dose of opioids: 20 MED to 50 MED doubles risk of OD. 20 MED to 90 MED has 9 times risk of OD. 91% of patients that survive an OD are prescribed opioids after the OD. 17% of lethal OD had survived a previous OD. 18

19 CDC: Opioid OD and Death About 50% of deaths associated with high dose opioid therapy MEDD of 90 mg or more About 50% of deaths associated with mixing opioids with other CNS depressants including alcohol. Opioid OD Tragically, 91% of people who survive an opioid OD are represcribed opioids. 17% of OD are not the first OD Larochelle, et al. Opioid prescribing after nonfatal overdose and association repeated overdose: a cohort study. Ann Int Med. 2016;164:

20 Opioid OD and Death A recent CDC study identified oxycodone the 3rd most deadly drug, while alprazolam was the 4th, and fentanyl the 5th most deadly drug. Warner M et al. Drugs most frequently Involved in Drug Overdose Deaths: United States, National Vital Statistics Reports Volume 65, Number 10. December 20, Dangerous Drug Combinations Gabapentin: A recent study observed that prescribing gabapentin with opioids significantly increased the risk of opioid related fatal overdoses. Gomes, T et al. Gabapentin, opioids, and the risk of opioid-related death: A population-based nested case control study. PLOS Med. Oct 3 rd, Any CNS Depressant: Benzodiazepines, Soma, etc. 20

21 Opioids Not for strains/sprains When prescribing for serious acute injury or surgery, limit quantity to 2-3 days. Manage patient expectations. Analgesics do not eliminate pain. Use the smallest dose possible. Tramadol is an opioid! It has abuse potential too. Not for chronic pain in the vast majority of cases. How to Prevent Opioid Addiction Do not use opioids for chronic pain!!! Numerous safer and more effective treatments are available. 21

22 Interventional Therapies Best evidence is for SCS Unstable psychosocial/behavioral issues reduces success Weak evidence for most interventions. Can be helpful in well selected individuals. In general, interventional techniques are over utilized. Conclusions Non-pharmaceutical treatments should be the primary focus Pharmaceutical treatments have small benefits Opioids have greater risk than benefit Disability is driven by unstable behavioral issues Unstable behavioral issues are risk factors to chemical cope with controlled substances Family and personal history of substance use disorders and unstable behavioral issues are risk factors for developing a substance use disorder with COT. The vast majority of chronic pain patients on COT are chemically coping (best case) or will qualify for a substance use disorder (worst case). 22

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