The risk of chronic pain and disability Tools to aid the primary care physician

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1 Perspectives in Pain The risk of chronic pain and disability Tools to aid the primary care physician by Dr. Jeff H. Ennis MSW, MD, FRCP(C) and Jonathan M. Ennis, BSc Dr, Jeff Ennis is an assistant professor at McMaster University specializing in rehabilitation medicine, and is clinical director of the East End Multidisciplinary Pain Management Program in Hamilton, Ontario. Jonathan M. Ennis, BSc, is a 1st year medical student at the University of Ottawa. Case study part I Mark T. is a steelworker who had a work- related injury three months ago. He presents with low back pain of two weeks duration. There s no pain radiating into his lower extremities, nor any long track signs. Bowel and bladder function are maintained. Mark hurt his back while prying apart two heavy plates of steel. He felt a sudden grabbing sensation. Chronic non-cancer pain is a growing health problem in Canada. A large national survey found it affected 29% of the population, with an average duration of pain lasting 10.7 years. 1 The average self-reported pain intensity, the survey found, was 6.3 on a scale from 1 to 10. Significant numbers of Canadians are receiving opioid analgesics these accounted for 22% of prescriptions for pain in this survey, with two-thirds of these being codeine. The social cost of chronic pain is far from negligible. A Danish study published in 2003 found that patients with chronic pain experienced twice as many missed workdays as others. They were seven times more likely to quit their job due to health reasons. They made twice as many contacts with health care professionals and used 25% more healthcare resources than the general population. 2 In Canada, almost one-half of people with chronic pain report being unable to attend social and family events, and the mean number of days absent from work due to chronic pain was 9. 3 The National Population Health Survey, , estimated that chronic pain costs the Canadian economy approximately $14,744 per person affected per year. 3 With the aging of Canada s population, it s expected that chronic pain will come to affect more than one in three Canadians and the related costs will skyrocket. A recent large population study, involving 15 European countries, pointed out that 40% of those suffering from chronic pain reported inadequate management of their problem. 4 An appreciation and understanding of pain is now an integral part of patient care. Pain is recognized as the fifth vital sign. Given this significant burden of illness, chronic pain demands a plan of management that reduces the suffering of patients and the economic burden to society. If patients at risk for developing chronic pain are treated early, the majority of studies indicate that disability can be decreased or prevented and the economic cost reduced. But no specific definition of early has been agreed upon. What is evident is that the sooner patients at risk can be identified and the focus of treatment switched from conservative pain management to multidisciplinary, cognitive behavioural rehabilitation, the better the outcomes will be It s therefore critical to spot at-risk patients as soon as possible after pain-related problems develop. Head first Psychological factors appear to be more significant risk factors for progression to chronicity than biomechanical or biomedical factors. 46 parkhurst exchange March 2011

2 Patients at risk require specialized treatment, ideally in a multidisciplinary pain management program. Patients at high risk respond favourably to this form of treatment while low-risk patients do not Chronic pain is a costly problem. But the research literature has demonstrated that it s less costly to provide high-risk patients with multidisciplinary treatment than to withhold such treatment, even though the up-front costs are higher than with conservative treatment. Multidisciplinary pain management programs provide similar pain reduction when compared with medical management, but nonpharmacologic rehabilitation is associated with better functional outcomes, greater reduction in healthcare utilization, increased likelihood of file closure with disability insurance providers and a lower risk of side effects and iatrogenic problems. Multidisciplinary pain programs have also been shown to be cost-effective when compared to surgery, with comparable outcomes. Judging risk of chronicity In order to identify patients at risk for developing chronic pain and disability, we clearly need to know the real risk factors. Primarycare physicians play a key role here, being the first to see the patient. The sooner that Table 1 Risk factors for the development of chronic pain and disability Non-malleable risk factors Social or systemic risk factors Physical factors associated with the development of chronic disability Yellow flags Age, levelling out between the age of 60 and 69 8,1,2,3 The presence of compensation, or insurance 4,8 Obesity 8 Comorbid psychiatric illness such as depression and/or posttraumatic stress disorder (PTSD) 16,17,5,16,17 A history of childhood abuse has been associated with the development of chronic pain in adulthood 6 Poor support system including a patient s social network and their family 8,16,17,19 Multiple tender-points 8 Early high pain/disability ratings 8,16,17,19 Socioeconomic status. There s a higher likelihood of developing chronic disability in low-income families 8,19 Number of painful areas 18 Alcohol/substance abuse 8 A lower level of education is a risk factor for developing chronic pain 8,19,7 Family history of pain 18 In whiplash, specifically-early reduced range of motion 16 Somatization 8 Fear/avoidance/ catastrophic thinking 10,8 Multiple work related issues including working with machines, blue collar work, work beyond the physical capacity of the individual, work that is monotonous, a feeling of no control at the workplace, critical work supervisor 9,8,19,20 March 2011 parkhurst exchange 47

3 risk can be identified, the sooner a multidisciplinary model of care can be provided. 15 Risk factors can be divided into four categories: 1. Factors that are non-malleable and can t be altered such as age. 2. Factors related to social/systemic issues such as level of education. 3. Physical factors such as obesity. 4. Psychological factors, or what are referred to as yellow flags such as co-morbid depression. 6 Table 1 provides a summary of these risk factors. Case study part 2 Physical examination of Mark reveals reduced range of movement of the lumbar spine in all planes. Very light palpation of the lumbar spine results in severe reported pain. His response is dramatic. He s referred for phy siotherapy. Mark is 48 years old. He grew up in a home marred by alcohol abuse on the part of both of his parents. This would often lead to physical abuse. He left school and home by 17 years of age and trained on the job. Before the injury, Mark rarely missed work, but he found his job repetitive and dull. Mark s supervisor was constantly critical of his work. Mark smoked a pack of cigarettes a day. He scored 7 on the Alcohol Use Disorders Identification Test (AUDIT) and he reported smoking marijuana three times a week on the Drug Use Questionnaire. The AUDIT assesses for problems related to alcohol use at the time of the assessment. A score of 8 indicates potential problems related to alcohol use and a score of 15 indicates alcohol abuse in a male. The Drug Use Questionnaire assesses for substance use over a patient s lifetime. This scale provides historical data but is not scored. Case study part 3 At three months follow-up Mark reports no improvement with treatment. His level of function has deteriorated. His score on the Pain Disability Index is 59. He s doing very little at home, spending most of his day sitting in a reclining chair. His family has told him that he should try to do as much as he can, but there s been no improvement and he s starting to wonder if he ll be crippled. Imaging Table 2 Tools to Aid in the Assessment of risk factors Risk factors Psychiatric illness: depression, anxiety, posttraumatic stress disorder Early, high pain and disability rating Alcohol abuse/substance abuse Somatization* 1 Fear avoidance/catastrophic thinking Scale Zung Depression Scale Zung Anxiety Scale PTSD Checklist VAS, Orebro Musculoskeletal Pain Questionnaire, Pain Disability Index AUDIT/Drug Use Questionnaire Orebro Musculoskeletal Pain Questionnaire, Fear Avoidance Questionnaire and Tampa Scale of Kinesiophobia Fear Avoidance Questionnaire/Tampa Scale of Kinesiophobia * There are a number of scales available that assess for the presence of somatization specifically. An example is the SCL90R. However, you must purchase a license in order to use this scale. The scales I have provided pick up some of the elements of somatization but are not specific to this disorder. These scales are available free of charge at (case-sensitive password PainTools54 ). 48 parkhurst exchange March 2011

4 shows degenerative disc disease of the lumbar spine. A surgical consultation concluded that Mark isn t a surgical candidate. Mark is reporting problems with sleep and has lost 6.8 kg since the injury. Mark s score on the Zung Depression Scale is 54 and on the Zung Anxiety Scale he scored 21. You initiate treatment with an antidepressant and refer Mark to an anesthetist for injection therapy. The Pain Disability Index is a simple method of measuring function across a variety of spheres in a person s life. A score of 59 is above scores typically seen in patients with chronic noncancer pain, indicating a low level of function. The Zung Depression Scale screens for depression. A score of 54 is indicative of mild depression. The Zung Anxiety Scale is a scale used to assess for generalized anxiety. A score of 21 is below the cut-off of 36, which would indicate the presence of generalized anxiety. Assessing for risk factors There are a number of validated clinical tools that can help in assessing yellow flag risk factors. I have made several available, with normative data, for your clinical use. All of these assessment tools can be found in the public domain and there are no issues related to copyright. All scales listed have established psychometric properties. These tools and a bibliography of the psychometric properties of these tools can be found at This website is password-protected to prevent non-clinicians from entering the site. The (case-sensitive) password is PainTools54. You may give these scales to your patients to complete at home. Have them return them to your office where they can be quickly scored and used in the assessment process. The non-malleable risk factors can be identified through the clinical history. Social and systemic risk factors may also be teased out using the history, or through the input of a clinical social worker. The physical examination is naturally essential to any clinical assessment of a patient with chronic pain. Given the significant psychiatric co-morbidity associated with chronic pain, which might include a mood disorder and/or somatoform disorder, psychiatrists should perform a physical exam during their assessments of members of this patient population even though physical exams aren t a normal part of a psychiatric consultation. 25 Examination for fibromyalgia tender points can help to assess for the risk factor of widespread pain. The presence of Waddell s signs is often used to support a diagnosis of malingering. But the research literature doesn t support this practice. Physicians are poor at catching liars 26 and in any case no real-world link has been demonstrated between the presence of multiple Waddell s signs and malingering. Waddell s signs do, however, tend to predict a poorer clinical outcome. 27 Case study part 4 At follow-up two months later, Mark s mood has improved, but his function remains poor. Injection therapy was not helpful and Mark thinks it might have made him worse. Now, there are days when he doesn t bother getting up until noon. His wife is becoming very frustrated. Mark avoids doing any chores at home. He asks you for a prescription for a cane. Mark scores 143 on the Orebro Musculoskeletal Questionnaire and 44 on the Tampa Scale of Kinesiophobia. Mark scored 36 on the work-subscale of the Fear Avoidance Scale and 17 on the physical subscale of this test. These results indicate clinically significant fear and avoidance. The Orebro Musculoskeletal Questionnaire measures the risk of a patient becoming chronically disabled and the likelihood that they will return to work. Scores above 130 indicate a high likelihood of chronic disability and a low likelihood of return to work. The March 2011 parkhurst exchange 49

5 Tampa Scale of Kinesiophobia measures fear of movement. A score of 44 indicates significant fear of movement. The 50 th percentile score is The Fear Avoidance Scale measures fear and avoidance as they relate to pain and activity. Work subscale scores above 34 and physical subscale scores above 14 are clinically significant. Case study part 5 Mark has multiple risk factors for developing chronic pain. Conservative care has not led to a positive result. You refer Mark for an assessment at a multidisciplinary pain management program. In clinical practice it s important that patients with pain be screened for risk factors for the development of chronic pain and disability. The sooner this assessment takes place, the better for the patient. Ideally, it should happen within six months of the onset of pain. This assessment can be repeated if appropriate care brings limited clinical progress. The literature doesn t specify what tests are required to identify a patient as being at risk for chronic pain and disability. In my clinical practice, however, one that focusses on the assessment and treatment of patients with chronic pain, I measure specific outcomes on some of the scales I ve provided to you to determine a patient s risk. These outcomes are as follows: A score over 130 on the Orebro Musculoskeletal Pain Questionnaire. On the Fear Avoidance Questionnaire a score greater than 34 on the Work subscale and greater than 14 on the Physical subscale. A patient score over 40 on the Tampa Scale of Kinesiophobia. High pain rating (over 8/10) and high score on the Pain Disability Index (greater than 45) without evidence of significant physical pathology. High scores for substance/alcohol abuse indicate the need for referral for appropriate treatment. If a patient is found to be at risk for chronic problems and functional impairment, they can be referred to a multidisciplinary cognitive behavioural pain program, the method of treatment most likely to lead to functional improvement in this clinical situation. Early identification and referral of patients at risk for developing chronic pain is the key to better outcomes and less disability. References 1. Moulin DE et al. Chronic pain in Canada prevalence, treatment, impact and the role of opioid analgesia. Pain Res Manag 2002;7(4): Eriksen J et al. Pain 2003;106: Statistics Canada Health Statistics Division, National Population Health Survey Overview 1996/ Breivik H et al. European Journal of Pain 2006;10(4): Bergman S. Best Practice & Research Clinical Rheumatology 2007;21(1): Molde Hagen, E et al. Spine 2003;28(20): Gatchel R et al. Journal of Occupational and Rehabilitation 2003;13(1): Burton K et al. Spine 1995;20(6): Linton SJ, Andersson T. Spine 2000;25(21): Wand B et al. Spine 2004;29(21): Brison RJ et al. Spine 2005;30(16): Linton S, Nordin E. Spine 2006;31(8): Linton SJ. American Journal of Industrial Medicine 2002;41: Ashburn, M, Staats, P. The Lancet 1999; 353(9167): Turk, D. Clinical Journal of Pain 2002;18(6): Sterling M et al. Pain 2006;122: Sterling M et al. Pain 2005;114: Bergman S et al. J Rheumatol 2002;29: Goldberg RT. Disability and Rehabilitation 1999;21(1): Valat JP et al. Rev Rhum Engl Ed 1997;64(3): Bogduk N. Neurol Clin 2004;22(1): Marhold C et al. Journal of Occupational Rehabilitation 2002;12(2): Sullivan MJL et al. Pain 2008;135: Gatchel RJ et al. Psychological Bulletin 2007;133(4): Garden G et al. Advances in Psychiatric Treatment 2005;11: Ekman, P, O Sullivan M. American Psychologist 1991:46(9): Fishbain D et al. Clin J Pain 2004;20(6): parkhurst exchange March 2011