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Consensus guidelines for the selection and implantation of patients with noncancer pain for intrathecal drug delivery.
Deer TR, Smith HS, Cousins M, et al.
Pain Physician. 2010 May-Jun;13(3):E175-213.
Intrathecal therapy offers an invasive alternative for the long-term management of select patients with intractable pain associated with various disease states, including those of noncancer origin. It is commonly accepted that proper patient selection is essential to optimizing treatment outcomes, yet the practice of candidate selection for device implantation varies widely. A multifaceted approach--with consideration of preexisting medical comorbidities; psychological status; associated social, technical, and economic issues; and response to intrathecal trialing--enables practitioners to fully evaluate the appropriateness of implanting a patient with an intrathecal drug delivery system. Yet, to date no standard set of guidelines have been developed to aid practitioners in navigating this evaluation process. Using experience- and knowledge-based expert opinion to systematically evaluate the available evidence, this article provides consensus guidelines aimed at optimizing the selection of patients with noncancer pain for intrathecal therapy. In conclusion, complete assessment of a patient's physical, psychological, and social characteristics, can guide practitioners in determining the appropriateness of initiating intrathecal therapy. These consensus guidelines are intended to assist with weighing this risk/benefit ratio of intrathecal therapy, thereby minimizing the potential for treatment failure, unacceptable adverse effects, and excess mortality.
Deer TR, Smith HS, Cousins M, et al.
Pain Physician. 2010 May-Jun;13(3):E175-213.
Intrathecal therapy offers an invasive alternative for the long-term management of select patients with intractable pain associated with various disease states, including those of noncancer origin. It is commonly accepted that proper patient selection is essential to optimizing treatment outcomes, yet the practice of candidate selection for device implantation varies widely. A multifaceted approach--with consideration of preexisting medical comorbidities; psychological status; associated social, technical, and economic issues; and response to intrathecal trialing--enables practitioners to fully evaluate the appropriateness of implanting a patient with an intrathecal drug delivery system. Yet, to date no standard set of guidelines have been developed to aid practitioners in navigating this evaluation process. -
The pain imaging revolution: advancing pain into the 21st century.
Borsook D, Sava S, Becerra L.
Neuroscientist. 2010 Apr;16(2):171-85.
The great advances in brain imaging techniques over the last few decades have determined a shift in our understanding of chronic pain conditions and opened the door for new opportunities to develop better diagnoses and perhaps better drug treatments. Neuroimaging has helped shape the concept of chronic pain from a disease affecting mainly the somatosensory system, to a condition in which emotional, cognitive, and modulatory areas of the brain are affected, in addition to degenerative processes. All these contribute to the development and maintenance of pain symptoms and comorbid features, including alterations in anxiety, depression, and cognitive processes. In this article the authors review the current understanding of the brain changes in chronic pain and the developments made possible by the use of various brain imaging techniques. They also discuss the possible applications of brain imaging to developing a "pain phenotype" that could aid in diagnostic and treatment choices of chronic pain conditions.
Borsook D, Sava S, Becerra L.
Neuroscientist. 2010 Apr;16(2):171-85.
The great advances in brain imaging techniques over the last few decades have determined a shift in our understanding of chronic pain conditions and opened the door for new opportunities to develop better diagnoses and perhaps better drug treatments. Neuroimaging has helped shape the concept of chronic pain from a disease affecting mainly the somatosensory system, to a condition in which emotional, cognitive, and modulatory areas of the brain are affected, in addition to degenerative processes. All these contribute to the development and maintenance of pain symptoms and comorbid features, including alterations in anxiety, depression, and cognitive processes. In this article the authors review the current understanding of the brain changes in chronic pain and the developments made possible by the use of various brain imaging techniques. -
Minimum Acceptable Outcomes After Lumbar Spinal Fusion.
Carragee EJ, Cheng I.
Spine J. 2010 Apr;10(4):313-20.
BACKGROUND CONTEXT: Defining success after spinal surgery remains problematic. The minimal clinically important difference (MCID) in pain or functional outcomes is a common metric often calculated independent of perceived risk and morbidity, which is an important consideration in large procedures such as spinal fusion and instrumentation. PURPOSE: The purpose of this study was to describe a method of assessing treatment success based on prospective, patient-reported "minimum acceptable" outcome for which they would undergo a procedure. These goals can then be compared at follow-up to gauge how frequently patient goals are met and determine correlation with patient satisfaction. STUDY DESIGN: This is a clinical descriptive study of the patient-reported minimum acceptable outcomes for spinal fusion surgery. OUTCOME MEASURES: Minimum acceptable outcomes were determined by patients on preoperatively administered standard questionnaires regarding ultimate pain intensity, functional outcome (Oswestry Disability Index [ODI]), medication usage, and work status. Satisfaction with outcomes was assessed at 2-year follow-up. METHODS: One hundred sixty-five consecutive patients undergoing lumbar fusion for either isthmic spondylolisthesis or disc degeneration were asked to preoperatively define on standard questionnaires their minimum acceptable outcomes after surgery. Two-year outcomes and satisfaction were subsequently reported and compared with the preoperatively determined minimum acceptable outcomes. RESULTS: Both the spondylolisthesis and the degenerative disc disease (DDD) groups reported that a high degree of improvement was the minimum acceptable threshold for considering spinal fusion. A large majority indicated that the minimum acceptable outcomes included at least a decrease in pain intensity to 3/10 or less, an improvement in ODI of 20 or more, discontinuing opioid medications, and return to some occupational activity. Achieving the minimum acceptable outcome was strongly associated with satisfaction at 2 years after surgery. Patients with compensation claims, psychological distress, and other psychosocial stressors were more likely to report satisfaction in the absence of achieving their minimum acceptable outcome. CONCLUSIONS: Patients with spondylolisthesis and DDD both have relatively high minimum acceptable outcomes for spinal fusion. In these cohorts, few subjects considered more commonly proposed MCIDs for pain and function as an acceptable outcome and report that they would not have surgery if they did not expect to achieve more than those marginal improvements. Although there was good concordance between achieving the minimum acceptable outcomes and ultimate satisfaction, patients with significant psychosocial factors (compensation claims, psychological distress, and others) are less likely to associate satisfaction with outcomes with actually achieving these improvements.
Carragee EJ, Cheng I.
Spine J. 2010 Apr;10(4):313-20.
BACKGROUND CONTEXT: Defining success after spinal surgery remains problematic. The minimal clinically important difference (MCID) in pain or functional outcomes is a common metric often calculated independent of perceived risk and morbidity, which is an important consideration in large procedures such as spinal fusion and instrumentation. PURPOSE: The purpose of this study was to describe a method of assessing treatment success based on prospective, patient-reported "minimum acceptable" outcome for which they would undergo a procedure. These goals can then be compared at follow-up to gauge how frequently patient goals are met and determine correlation with patient satisfaction. STUDY DESIGN: This is a clinical descriptive study of the patient-reported minimum acceptable outcomes for spinal fusion surgery. -
The American College of Rheumatology preliminary diagnostic criteria for fibromyalgia and measurement of symptom severity.
Wolfe F, Clauw, DJ, Fitzcharles MA, et al.
Arthritis Care Res (Hoboken). 2010 May;62(5):600-10.
OBJECTIVE: To develop simple, practical criteria for clinical diagnosis of fibromyalgia that are suitable for use in primary and specialty care and that do not require a tender point examination, and to provide a severity scale for characteristic fibromyalgia symptoms. METHODS: We performed a multicenter study of 829 previously diagnosed fibromyalgia patients and controls using physician physical and interview examinations, including a widespread pain index (WPI), a measure of the number of painful body regions. Random forest and recursive partitioning analyses were used to guide the development of a case definition of fibromyalgia, to develop criteria, and to construct a symptom severity (SS) scale. RESULTS: Approximately 25% of fibromyalgia patients did not satisfy the American College of Rheumatology (ACR) 1990 classification criteria at the time of the study. The most important diagnostic variables were WPI and categorical scales for cognitive symptoms, unrefreshed sleep, fatigue, and number of somatic symptoms. The categorical scales were summed to create an SS scale. We combined the SS scale and the WPI to recommend a new case definition of fibromyalgia: (WPI > or =7 AND SS > or =5) OR (WPI 3-6 AND SS > or =9). CONCLUSION: This simple clinical case definition of fibromyalgia correctly classifies 88.1% of cases classified by the ACR classification criteria, and does not require a physical or tender point examination. The SS scale enables assessment of fibromyalgia symptom severity in persons with current or previous fibromyalgia, and in those to whom the criteria have not been applied. It will be especially useful in the longitudinal evaluation of patients with marked symptom variability.
Wolfe F, Clauw, DJ, Fitzcharles MA, et al.
Arthritis Care Res (Hoboken). 2010 May;62(5):600-10.
OBJECTIVE: To develop simple, practical criteria for clinical diagnosis of fibromyalgia that are suitable for use in primary and specialty care and that do not require a tender point examination, and to provide a severity scale for characteristic fibromyalgia symptoms. METHODS: We performed a multicenter study of 829 previously diagnosed fibromyalgia patients and controls using physician physical and interview examinations, including a widespread pain index (WPI), a measure of the number of painful body regions. Random forest and recursive partitioning analyses were used to guide the development of a case definition of fibromyalgia, to develop criteria, and to construct a symptom severity (SS) scale. -
Revised American Pain Society Patient Outcome Questionnaire for Quality Improvement of Pain Management in Hospitalized Adults
Gordon DB, Polomano RC, Pellino TA, et al.
J Pain. 2010 Apr 16.
Quality improvement (QI) is a compilation of methods adapted from psychology, statistics, and operations research to identify factors that contribute to poor treatment outcomes and to design solutions for improvement. Valid and reliable measurement is essential to QI using rigorously developed and tested instruments. The purpose of this article is to describe the evolution of the American Pain Society Patient Outcome Questionnaire (APS-POQ) for QI purposes and present a revised version (R) including instrument psychometrics. An interdisciplinary task force of the APS used a step-wise, empiric approach to revise, test, and examine psychometric properties of the society's original POQ. The APS-POQ-R is designed for use in adult hospital pain management QI activities and measures 6 aspects of quality, including (1) pain severity and relief; (2) impact of pain on activity, sleep, and negative emotions; (3) side effects of treatment; (4) helpfulness of information about pain treatment; (5) ability to participate in pain treatment decisions; and (6) use of nonpharmacological strategies. Adult medical-surgical inpatients (n = 299) from 2 hospitals in different parts of the United States participated in this study. Results provide support for the internal consistency of the instrument subscales, construct validity and clinical feasibility. PERSPECTIVE: This article presents the initial psychometric properties of the APS-POQ-R for quality improvement purposes of hospitalized adult patients. Validation in additional groups of patients will be needed to demonstrate its generalizability. Copyright © 2010 American Pain Society. Published by Elsevier Inc. All rights reserved.
Gordon DB, Polomano RC, Pellino TA, et al.
J Pain. 2010 Apr 16.
Quality improvement (QI) is a compilation of methods adapted from psychology, statistics, and operations research to identify factors that contribute to poor treatment outcomes and to design solutions for improvement. Valid and reliable measurement is essential to QI using rigorously developed and tested instruments. The purpose of this article is to describe the evolution of the American Pain Society Patient Outcome Questionnaire (APS-POQ) for QI purposes and present a revised version (R) including instrument psychometrics. An interdisciplinary task force of the APS used a step-wise, empiric approach to revise, test, and examine psychometric properties of the society's original POQ. -
The Role of Glia and the Immune System in the Development and Maintenance of Neuropathic Pain.
Vallejo R, Tilley DM, Vogel L, et al.
Pain Pract. 2010 Apr 5.
Abstract Neuropathic pain refers to a variety of chronic pain conditions with differing underlying pathophysiologic mechanisms and origins. Recent studies indicate a communication between the immune system and the nervous system. A common underlying mechanism of neuropathic pain is the presence of inflammation at the site of the damaged or affected nerve(s). This inflammatory response initiates a cascade of events resulting in the concentration and activation of innate immune cells at the site of tissue injury. The release of immunoactive substances such as cytokines, neurotrophic factors, and chemokines initiate local actions and can result in a more generalized immune response. The resultant neuroinflammatory environment can cause activation of glial cells located in the spinal cord and the brain, which appear to play a prominent role in nociception. Glial cells, also known as neuroglia, are nonconducting cells that modulate neurotransmission at the synaptic level. Glial cells can be subdivided into two primary categories: microglia and macroglia, which include astrocytes and oligodendrocytes. Astrocytes and microglia are known to play a role in the development, spread, and potentiation of neuropathic pain. Following peripheral nociceptive activation via nerve injury, microglia become activated and release pro-inflammatory cytokines such as tumor necrosis factor-alpha, interleukin-1beta, and interleukin-6, thereby initiating the pain process. Microglia propagate the neuroinflammation by recruiting other microglia and eventually activating nearby astrocytes, which prolongs the inflammatory state and leads to a chronic neuropathic pain condition. Our review focuses on the role of glia and the immune system in the development and maintenance of neuropathic pain.
Vallejo R, Tilley DM, Vogel L, et al.
Pain Pract. 2010 Apr 5.
Abstract Neuropathic pain refers to a variety of chronic pain conditions with differing underlying pathophysiologic mechanisms and origins. Recent studies indicate a communication between the immune system and the nervous system. A common underlying mechanism of neuropathic pain is the presence of inflammation at the site of the damaged or affected nerve(s). This inflammatory response initiates a cascade of events resulting in the concentration and activation of innate immune cells at the site of tissue injury. The release of immunoactive substances such as cytokines, neurotrophic factors, and chemokines initiate local actions and can result in a more generalized immune response. The resultant neuroinflammatory environment can cause activation of glial cells located in the spinal cord and the brain, which appear to play a prominent role in nociception. -
Costs of Opioid Abuse and Misuse Determined from a Medicaid Database.
McAdam-Marx C, Roland CL, Cleveland J, et al.
J Pain Palliat Care Pharmacother. 2010;24(1):5-18.
This study determined the associations between opioid abuse, dependence, and poisonings on costs and comorbidities in the Medicaid population. Medicaid patients in the Medicaid Analytic eXtract (MAX) files from 2002 to 2003 with 12 months of continuous eligibility, age >or=12 years, and with an opioid abuse/dependence-related diagnosis, including opioid abuse, dependence, or poisoning, in 2002 (index date) were matched 3:1 to Medicaid patients with no such diagnosis (controls). Medical costs by claim type incurred 12 months post index date were compared as was the prevalence of select comorbidities. The authors conducted a two-step multivariate regression analysis adjusted for patient characteristics that could influence cost outcomes. Opioid abuse/dependence prevalence was 8.7 per 1000 in 2002-2003. A total of 50,162 patients with abuse or dependence-related diagnoses were matched to 150,486 control patients. Total costs were significantly higher for the abuse/dependence patients ($14,537) than matched controls ($8,663) (P < .001). When controlling for baseline characteristics, adjusted costs continued to be higher for abuse/dependence patients ($23,556 versus $8,436; P < .001). A total of 83.7% of abuse/dependence patients and 51.6% of controls had >or=1 of the predefined comorbidities. Other substance abuse (odds ratio [OR] 9.4), hepatitis A, B, or C (OR 8.8), and poisonings (OR 8.5) were highly associated with a diagnoses for opioid abuse or dependence (P < .001). Medicaid opioid abuse/dependence patients had more comorbidities and higher medical costs in 2002-2003 than Medicaid control patients. Successful interventions to prevent opioid abuse and manage comorbidities could help to reduce costs associated with opioid abuse in the Medicaid population.
McAdam-Marx C, Roland CL, Cleveland J, et al.
J Pain Palliat Care Pharmacother. 2010;24(1):5-18.
This study determined the associations between opioid abuse, dependence, and poisonings on costs and comorbidities in the Medicaid population. Medicaid patients in the Medicaid Analytic eXtract (MAX) files from 2002 to 2003 with 12 months of continuous eligibility, age >or=12 years, and with an opioid abuse/dependence-related diagnosis, including opioid abuse, dependence, or poisoning, in 2002 (index date) were matched 3:1 to Medicaid patients with no such diagnosis (controls). Medical costs by claim type incurred 12 months post index date were compared as was the prevalence of select comorbidities. The authors conducted a two-step multivariate regression analysis adjusted for patient characteristics that could influence cost outcomes. Opioid abuse/dependence prevalence was 8.7 per 1000 in 2002-2003. -
Pharmacotherapy in fibromyalgia (FM) - Implications for the underlying pathophysiology.
Schmidt-Wilcke T, Clauw DJ.
Pharmacol Ther. 2010 Apr 11.
Although chronic pain states are highly prevalent, the underlying neurobiological mechanisms involved in causing pain are incompletely understood. This is especially true for the so-called chronic functional pain syndromes and pain syndromes of unknown origin, such as fibromyalgia (FM), in which no structural correlates of pain experience, in terms of a nociceptive source, can clearly be defined. In addition to limited therapeutic options and often unsatisfactory treatment, such patients often struggle with socio-medical acceptance of their pain condition. As FM has become more widely recognized, options available for treatment have grown along with our understanding of the neurobiological mechanisms underlying chronic pain experience and concomitant symptoms. The current review aims to provide an overview of existing pharmacotherapies for FM, and their implication for the underlying pathophysiology. Further we discuss some of the potential targets that have been recently identified that may hold promise for the development of novel treatments. Copyright © 2010. Published by Elsevier Inc.
Schmidt-Wilcke T, Clauw DJ.
Pharmacol Ther. 2010 Apr 11.
Although chronic pain states are highly prevalent, the underlying neurobiological mechanisms involved in causing pain are incompletely understood. This is especially true for the so-called chronic functional pain syndromes and pain syndromes of unknown origin, such as fibromyalgia (FM), in which no structural correlates of pain experience, in terms of a nociceptive source, can clearly be defined. In addition to limited therapeutic options and often unsatisfactory treatment, such patients often struggle with socio-medical acceptance of their pain condition. As FM has become more widely recognized, options available for treatment have grown along with our understanding of the neurobiological mechanisms underlying chronic pain experience and concomitant symptoms. -
An algorithm for the diagnosis and management of chest pain in primary care.
Yelland M, Cayley WE Jr, Vach W, et al.
Med Clin North Am. 2010 Mar;94(2):349-74.
This article focuses on the key clinical and investigatory features that help differentiate the multiple causes of chest pain in adults in assessment of patients with undifferentiated chest pain in primary care using history, physical examination, and basic initial investigations. The initial treatment of many of the causes is discussed. Some treatments not only relieve symptoms but also provide further diagnostic information based on the response to treatment. Guidance for referral for specialist assessment and further investigations is provided, but the diagnostic usefulness of these measures is not discussed.
Yelland M, Cayley WE Jr, Vach W, et al.
Med Clin North Am. 2010 Mar;94(2):349-74.
This article focuses on the key clinical and investigatory features that help differentiate the multiple causes of chest pain in adults in assessment of patients with undifferentiated chest pain in primary care using history, physical examination, and basic initial investigations. The initial treatment of many of the causes is discussed. Some treatments not only relieve symptoms but also provide further diagnostic information based on the response to treatment. Guidance for referral for specialist assessment and further investigations is provided, but the diagnostic usefulness of these measures is not discussed. -
The Canadian STOP-PAIN project – Part 1: Who are the patients on the waitlists of multidisciplinary pain treatment facilities?
Choinière M, Dion D, Peng P, et al.
Can J Anaesth. 2010 Apr 15.
PURPOSE: The Canadian STOP-PAIN Project assessed the human and economic burden of chronic pain in individuals on waitlists of Multidisciplinary Pain Treatment Facilities (MPTF). This article presents the patients' bio-psycho-social profile. METHODS: A sample of 728 patients was recruited from waitlists of eight university-affiliated MPTFs across Canada. Subjects completed validated questionnaires to: 1) assess the characteristics and impact of their pain; and 2) evaluate their emotional functioning and quality of life (QoL). Follow-up questionnaires were completed by a subgroup of 271 patients three months later. RESULTS: Close to 2/3 of the participants reported severe pain (>/= 7/10) that interfered substantially with various aspects of their daily living and QoL. Severe or extremely severe levels of depression were common (50.0%) along with suicidal ideation (34.6%). Patients aged > 60 yr were twice as likely to experience severe pain (>/= 7/10) as their younger counterparts (P = 0.002). Patients with frequent sleep problems were more at risk of reporting severe pain (P </= 0.003). Intense pain was also associated with a greater tendency to catastrophize (P < 0.0001) severe depressive symptoms (P = 0.003) and higher anger levels (P = 0.016). Small but statistically significant changes in pain intensity and emotional distress were observed over a three-month wait time (all P < 0.05). CONCLUSION: This study highlights the severe impairment that patients experience waiting for treatment in MPTFs. Knowing that current facilities cannot meet the clinical demand, it is clear that effective prevention/treatment strategies are needed earlier in primary and secondary care settings to minimize suffering and chronicity.
Choinière M, Dion D, Peng P, et al.
Can J Anaesth. 2010 Apr 15.
PURPOSE: The Canadian STOP-PAIN Project assessed the human and economic burden of chronic pain in individuals on waitlists of Multidisciplinary Pain Treatment Facilities (MPTF). This article presents the patients' bio-psycho-social profile. METHODS: A sample of 728 patients was recruited from waitlists of eight university-affiliated MPTFs across Canada. Subjects completed validated questionnaires to: 1) assess the characteristics and impact of their pain; and 2) evaluate their emotional functioning and quality of life (QoL). Follow-up questionnaires were completed by a subgroup of 271 patients three months later. RESULTS: Close to 2/3 of the participants reported severe pain (>/= 7/10) that interfered substantially with various aspects of their daily living and QoL. Severe or extremely severe levels of depression were common (50.0%) along with suicidal ideation (34.6%).
