Education

2015 Annual Scientific Meeting Registration Is Now Open

Registration for the 2015 Annual Scientific Meeting is now open. The 2015 annual meeting unites hundreds of pain researchers and clinicians from across the country. Join your colleagues in Palm Springs, May 13–16, for an exciting educational experience.

The educational program, which includes keynote and plenary lectures, symposia, workshops, and awards lectures, will change the way you think about and treat pain research and management across several disciplines.

Register now so you don’t miss out on any of these great programs, including the following plenary lectures.

Thursday, May 14 (9–9:30 am)
Inside Information: Knowns and Unknowns
Jerry Gebhart, PhD

The internal organs are sparsely innervated relative to other tissues but uniquely are innervated by two nerves with some overlapping while also distinct functions. Visceral pain is not reliably produced by typical tissue-damaging stimuli, and chronic visceral pain often exists in the absence of a clear pathobiological cause. Improved management of chronic visceral pain conditions relies on improved understanding of underlying mechanisms, which likely differ between different organs.

Friday, May 15 (7:30–8 am)
Cannabis and Pain: Old Drug, New Perspectives
Mark Ware, MD MRCP (UK) MSc

The primary reason for patients’ self-reported medical use of cannabis is for pain management. The pain management community is deeply aware of our need for new approaches to manage chronic pain. Can these two positions be reconciled in an evidence-based manner? Is there a role of cannabis or its derivatives, the cannabinoids, in modern pain management? This presentation will explore the scientific rationale for cannabinoids in pain modulation, the epidemiology of cannabis use in pain, and the evidence base for cannabis in pain management. Attendees will be challenged to confront their own perceptions of cannabis and to consider how the stigma of cannabis influences their therapeutic decisions as well as encouraged to participate in finding ways to safely and constructively deal with the exploding reality of medical cannabis. We are facing an issue that can no longer be ignored, a therapy that is increasingly available through not regulatory approval but court challenges and the ballot box. How we respond is a matter of importance to the health profession, the policy makers, the general public and, most importantly, our patients.

Friday, May 15 (8–8:30 am)
Effect of Environment on the Long-Term Consequences of Chronic Pain
Catherine Bushnell, PhD

There is accumulating evidence that chronic pain leads to consequences that go far beyond the pain itself. Chronic pain patients show associated anxiety and depression, as well as deficits in cognitive functioning. Rodent models confirm similar emotional and cognitive changes in controlled longitudinal studies, suggesting that the effects are caused by the chronic pain condition, rather than reflecting unrelated differences between individuals with chronic pain and control subjects. Brain imaging studies in both pain patients and in rodent pain models show alterations in gray matter volume, white matter integrity and even epigenetic changes in the brain. Despite the widespread nature of the alterations related to chronic pain, there is now evidence that these effects can be prevented or reversed by environmental factors. In human pain patients, lifestyle choices, such as yoga or meditation, reduce pain perception and counter age-related decreases in gray matter density and white matter integrity. This contrasts with chronic pain that accelerates gray matter loss and disrupts white matter integrity. Rodent models show that increased stress alters pain behaviors, whereas socially and physically enriched environments reduce such behavior and reduces pain-related brain changes. Together, these data indicate that the far-reaching adverse effects of chronic pain are not inevitable and may be reduced or prevented by environmental factors that could affect pain modulatory systems in the brain.

Saturday, May 16 (9–9:45 am)
“Listening” and “Talking” to Neurons: Clinical Implications of Glial Dysregulation of Pain, Opioid Actions, and Drugs of Abuse
Linda Watkins, PhD

Work over the last 20 years has challenged classical views of pain and opioid actions as being mediated solely by neurons. Recently, this challenge to classical views has extended to drug abuse. Glia (microglia and astrocytes) in the central nervous system are key players in chronic pain; compromising the efficacy of opioids for suppressing pain; contributing to opioid tolerance and dependence or withdrawal; and potently contributing to the rewarding effects of opioids, cocaine, methamphetamine, and alcohol. Further, glial reactivity can be “primed” to create enduring, amplified neuroinflammation, thereby contributing to the transition of acute-to-chronic pain.

Intriguingly, the glial activation receptor that creates neuroinflammation under conditions of chronic pain is one and the same receptor that is activated by opioids and other abused drugs. Importantly, this glial activation receptor is not the neuronal opioid receptor that suppresses pain. Indeed, clinically relevant therapeutics targeting this glial activation receptor in particular or glially-drive neuroinflammation more generally have shown remarkable efficacy as stand-alone treatments for neuropathic pain, improving the clinical utility of opioids and suppressing drug abuse. As such, compounds are rapidly moving toward clinical trials and translation of laboratory findings to humans is approaching.

Don’t miss out. Register now!

Clinical and Basic Science Data Blitz

The Clinical and Basic Science Data Blitz will be held on Wednesday, May 13, 6:15–8:15 pm, in Palm Springs, CA, as part of the 34th Annual APS Annual Scientific Meeting. This year’s Data Blitz will feature research from the Spring Pain meeting as well as presentations submitted by annual meeting attendees. The blitz will include selected presentations of new research in a rapid format, with presenters having 5 minutes to present data and 5 additional minutes for questions from the audience. The blitz will be moderated by Todd Vanderah, PhD; Michael Jankowski, PhD; Benedict Kolber, PhD; and the 2014 Data Blitz session winner, Peter Grace, PhD.

APS will issue a call for submissions for the Data Blitz in February 2015. Submissions will be due on March 19.

Research

2015 Rita Allen Foundation Award Call for Applications

The Rita Allen Foundation (RAF) and APS announce the 2015 Award in Pain. The RAF and APS may award two grants in the amount of $50,000 annually, for a period of up to 3 years to those research proposals demonstrating the greatest merit and potential for success.

Candidates must have completed their training and provided persuasive evidence of distinguished achievement or extraordinary promise in basic science research in pain. Candidates should be in the early stages of their career with an appointment at the faculty level. The entire award is to be allocated to projects specifically chosen by the recipient. Overhead is not supported.

To learn more about the RAF Award in Pain, please visit the APS website, where additional details and an application link are posted.

Young Investigator Travel Award Program

APS is planning to offer travel stipends via the Young Investigator Travel Award for the 2015 APS Annual Scientific Meeting. A limited number of travel awards will be available to individuals presenting poster abstracts at the meeting, May 13–16, 2015, in Palm Springs, CA. Applicants may be from any research training background (basic or clinical science, psychology, medicine, or biostatistics) and may be at any level in training (students, residents, predoctoral trainees, postdoctoral fellows, and those who have completed their postdoctoral training within the past 3 years). Applicants must be APS members and must have an abstract accepted for presentation at the 2015 annual meeting. Applications from nonmembers will not be considered.

To apply for the travel award, complete the online application, which will be available on the APS website after January 6. Note that an applicant’s abstract must be accepted for presentation to be considered for this grant. Poster abstract acceptance letters will be e-mailed to primary authors in late December, and a listing of accepted abstracts, by primary author, will be available on the website by December 31. Please check the abstract acceptance list before applying for a Young Investigator Travel Award.

Applications must be completed online by February 10, 2015.

Applications will be reviewed by the APS Scientific Program Committee and recipients selected in February. Recipients will be notified in March. Those applicants selected to receive a 2015 award will receive their travel grants at the annual meeting.

Interagency Pain Research Coordinating Committee Accepting Nominations for New Members

The Interagency Pain Research Coordinating Committee (IPRCC) was established under the Affordable Care Act to

• develop a summary of advances in pain care research supported or conducted by the Federal agencies relevant to the diagnosis, prevention, and treatment of pain and diseases and disorders associated with pain;
• identify critical gaps in basic and clinical research on the symptoms and causes of pain;
• make recommendations to ensure that the activities of the National Institutes of Health (NIH) and other Federal agencies are free of unnecessary duplication of effort;
• make recommendations on how best to disseminate information on pain care; and
• make recommendations on how to expand partnerships between public entities and private entities to expand collaborative, cross-cutting research.

Nominations for new committee members are being solicited and will be accepted through January 12, 2015 (please note the extended date from the FRN). Nominees will be considered to fill openings due to the completion of current member terms. Details and required materials for submissions are provided on the Federal Register.

Thank You, 2015 Abstract Submitters

APS received 500 abstract submissions for the 2015 APS Annual Scientific Meeting. Of the submissions, 461 are complete and have been reviewed by the Scientific Program Committee.

Primary authors will be notified by e-mail in late December regarding the status of their submission(s). A listing of accepted abstracts, by primary author, will be posted on the APS website at the end of December.

The 2015 annual meeting in Palm Springs will feature all 461 poster presentations on display throughout the Experience Exchange hours on Wednesday, Thursday, and Friday during the meeting. This promises to be APS’s best meeting yet. It will provide you with opportunities to discuss pain research and treatment, discover new approaches, interact with leaders and early career professionals in the field of pain, and apply new skills to your research or practice.

Members

Welcome New Members

APS is pleased to welcome and recognize the following new members from November 2014:

Funding Announcements

Clinical Evaluation of Adjuncts to Opioid Therapies for the Treatment of Chronic Pain (R01)

This funding opportunity announcement (FOA) aims to fund applications designed to assess the clinical value of adjuncts prescribed to chronic pain patients together with opioid analgesics. Adjuncts of interest are either approved by the U.S. Food and Drug Administration (FDA) or have previously been studied as an investigational new drug. Studies with adjuncts of interest should be focused on enhancing analgesia rather than on reducing an adverse effect. A secondary purpose is to increase awareness among opioid prescribers of the potential value of adjunctive therapies by focused data dissemination.

It is hoped that by increasing availability of data describing the use of opioid adjuncts, their use will increase and levels of opioids needed for analgesia will diminish. Reductions in the dosage of opioids prescribed would improve the quality of life of chronic pain patients by reducing opioid-associated adverse effects and lowering the risk of addiction development.

Studies should examine clinical populations and address whether a proposed adjunct can reduce the dose of opioid required for analgesia compared with opioid monotherapy. Applications will be evaluated on the feasibility, scientific rigor, and likely value of the proposed outcomes of randomized control trials (RCTs) to study opioid-adjunct combinations. In addition, the investigators should describe their plan to disseminate the study results. This plan will be evaluated with a view to how effectively the study results will be communicated to the types of healthcare providers who typically prescribe opioids to the chronic pain population under examination.

The purpose of this FOA is to examine adjunctive therapies to reduce the need for opioids in chronic pain patients. Therefore, in the patient group under investigation the pain syndrome should chronologically precede opioid exposure and the opioids should be prescribed as a treatment for the pain.

In the population proposed to be studied, the subjects should be etiologically homogenous and symptomatically well defined. Examples of such chronic pain populations in which opioids often are prescribed include patients with radicular cervical pain, metastatic bone pain, or peripheral neuropathies.

Studies should use an RCT design to examine opioid and adjunct formulations that are either typically used in the outpatient chronic pain population under study or are feasible for daily use in that population. For example, a formulation that requires once a day oral dosing is likely to be of much higher programmatic interest than a formulation requiring multiple daily dosing or intrathecal administration. Adjuncts to be examined should preferably be FDA approved, examples of which would include pregabalin, duloxetine, or dronabinol. However, agents that currently are being (or previously have been) studied as investigational new drugs (for example, Sativex/Nabiximols) also will be considered.

Submissions were accepted beginning September 5 and letters of intent are due 30 days before applications are due. For more information about this funding opportunity, visit the NIH grants page.

Development of Opioid and Adjuvant Fixed Combination Dosage Forms for the Treatment of Chronic Pain with Reduced Addiction Potential (R41/R42)

This funding opportunity announcement seeks small business organizations to develop opioid and adjuvant drug combinations within a single dosage form for treatment of a pain condition. The drug combination should provide improved analgesia when compared with the same dose (morphine equivalents) of opioid monotherapy. Such dosage forms should minimize opioid exposure while optimizing analgesia to reduce risk of addiction and limit severity of other opiate adverse effects.

When designing this new product, investigators should consider FDA guidance (21 CFR 300.50) and address the following issues. Both of the agents contained in the proposed new product should currently have at least one existing FDA-approved indication, as well as some existing clinical evidence to support the use of the chosen adjuvant-opioid combination and a reasonable expectation that the combination will present minimal drug-drug interaction concerns. The application should emphasize available evidence that the chosen drugs and doses in the combination will allow a substantial patient population to gain sufficient analgesic value from the contained opioid dose while the adjuvant dose remains within a safe and effective "therapeutic window." One example of a potentially viable adjuvant is gabapentin, a drug known to reduce neuropathic pain and to which patients typically exhibit no more than mild adverse effects. Gabapentin typically does not induce substantial drug interactions because it is eliminated as parent drug by renal excretion and does not bind extensively to blood proteins.

The adjuvant should be chosen for a capacity to increase overall analgesia, rather than an ability to reduce opioid adverse effects. For example, inclusion of a poorly absorbed opioid receptor antagonist, with the intent of reducing constipation, would not be considered of high programmatic interest.

The combination dosage form proposed by the application should provide sustained relief when it is the only analgesic used and is administered no more than three times in a 24-hour period. The formulation should be such that a patient with reasonable mobility is able to self-administer the drug (e.g., oral dosage form).

The application should propose late-stage drug development–oriented studies that significantly drive the project toward an ultimate aim of a New Drug Application [505(b)(1 or 2)] or Abbreviated New Drug Application [505(j)] for the treatment of a long-term pain condition.

Studies planned for Phase 1 of the project should focus on issues that concern the feasibility of the project. The exact nature of such studies will differ depending on the proposed drug combination project.

Studies that might be appropriate for Phase 1 STTR applications include, but are not limited to

• development of a formulation that safely delivers the desired amount of both agents over an appropriate dosing interval
  
• preclinical studies demonstrating additive or synergistic analgesia with the opioid-adjuvant combination
  
• studies to provide data for an Investigational New Drug (IND) submission, such as short-term stability studies
  
• pre-IND consultations with an FDA project management group and development of the IND documentation.

Examples of projects appropriate for Phase 2 of an STTR award might include

• pharmacokinetic absorption and disposition studies to demonstrate the bioequivalence between approved dosage forms and the proposed product
  
• proof of concept clinical studies. Appropriate outcome measures might aim to detect and distinguish value added by an opioid adjunctive therapy, whether due to improved analgesia or reduced required opioid dosage.

Submissions were accepted beginning March 5 and letters of intent are due 30 days before applications are due. For more information about this funding opportunity, visit the NIH grants page.

Neurobiology of Migraine (R01)

This funding opportunity announcement (FOA) is issued by the National Institute of Neurological Disorders and Stroke (NINDS) in conjunction with the National Institutes of Health (NIH) Pain Consortium. It solicits R01 grant applications from institutions and organizations to perform innovative research that will elucidate the mechanisms underlying migraine; expand our current knowledge of the role of genetic, physiological, biopsychosocial, and environmental influences in migraine susceptibility and progression; and explore new therapeutic targets and therapies for acute migraine management and longer term prevention.

The National Center for Complementary and Alternative Medicine (NCCAM) is interested in research that would elucidate the mechanisms by which a given complementary or integrative health approach beneficially affects migraine, either as an acute intervention or prophylactically. For this FOA, complementary or integrative health approaches could include those within the “mind and body” domain but not in the “natural products” domain and would include, but are not limited to, meditation, mindfulness, yoga, tai chi, qi-gong, acupuncture, massage, and spinal manipulation. The primary outcomes for these studies should be focused directly on the mechanism(s), though it may be appropriate to have secondary outcomes that assess clinical outcomes. There should be sufficient prior data to indicate either efficacy or effectiveness of the proposed complementary or integrative health approach.

The National Institute for Dental and Craniofacial Research (NIDCR) is interested in the neurobiological mechanisms underlying migraine headache as they pertain to overlaps with pathophysiological mechanisms of chronic temporomandibular and other orofacial pain disorders. Research examining common genetic, environmental, neurobiological, and biobehavioral factors underlying the co-occurrence of these disorders is encouraged. NIDCR is interested in funding meritorious research that focuses on studies addressing the comorbidity of temporomandibular and other orofacial disorders and migraine headache.

NIDCR is interested in the development of diagnostic, interventional, and novel therapeutic tools for headache pain associated with a variety of communication disorders such as tinnitus, Meniere’s disease, odynophagia, and burning mouth syndrome. Any individual(s) with the skills, knowledge, and resources necessary to carry out the proposed research as the program director or principal investigator (PD or PI) is invited to work with his or her organization to develop an application for support. Individuals from underrepresented racial and ethnic groups as well as individuals with disabilities always are encouraged to apply for NIH support.

Submissions will be accepted beginning May 5. For more information about this funding opportunity, visit the NIH grants page.

Summaries

The Journal of Pain Highlights

The following highlights summarize selected articles from The Journal of Pain (Volume 15, Issue 12, December 2014 Issue).

A Pain Research Agenda for the 21st Century
Robert W. Gereau, Kathleen A. Sluka, William Maixner, Seddon R. Savage, Theodore J. Price, Beth Murinson, Mark D. Sullivan, and Roger B. Fillingim, American Pain Society

At least 100 million Americans suffer from chronic pain, according to the Institute of Medicine. Unfortunately, there is inadequate funding to support scientific research that could lead to effective new therapies for pain. Recognizing this dilemma, the American Pain Society (APS) released its Pain Research Agenda for the 21st Century, which identifies promising but underfunded approaches to develop new treatments and help make currently used pain medications safer and more effective.

Published in the December issue of The Journal of Pain, the APS Pain Research Agenda is a goal-oriented approach emphasizing important outcomes that must be achieved to advance pain treatment. It states, “The most direct path to achieving dramatic advances in pain treatment is through substantially increased investment in pain research and education, which would enable the pursuit of an aggressive translational pain-research agenda.”

“Chronic pain must become a national priority. Much larger investments have been made, such as decoding the human genome and halting the HIV epidemic, and the results have been nothing short of transformative,” said APS President Gregory Terman, MD PhD, professor of anesthesiology, University of Washington Medical School. “Is the daily suffering of 100 million Americans any less important?”

“Our work in developing the pain research agenda showed that even the most optimistic estimates indicate that pain research is woefully underfunded relative to its prevalence, disease burden, and economic toll,” said co-author and former APS President Roger B. Fillingim, PhD, professor, College of Dentistry, and director, Pain Research and Intervention Center of Excellence at the University of Florida.

He noted that pain research expenditures at the National Institutes for Health (NIH) account for just 1% of the NIH research budget or $4 per affected individual, compared to cancer and HIV for which $431 and $2,562, respectively, are spent per affected person.

The APS Pain Research Agenda identifies five broad goals:

1. Develop novel pain treatments that enhance clinically meaningful pain relief and functional improvement with acceptable adverse effects.
2. Expedite progress toward the prevention, diagnosis, and management of pain conditions.
3. Optimize the use of access to currently available treatments that are known to be effective.
4. Understand the impact of health policies and systems on pain treatment.
5. Improve pain management through education research.

Pain Research Agenda Identifies Potential New Therapies

The APS Pain Research Agenda states that physiologic and pharmacologic pain research has produced significant advances that identify three promising paths of therapeutic development for pain. They are

• interventions targeted at blocking pain signals at their source
• therapeutics that disrupt or reverse molecular pain mechanisms
• therapeutics that modulate or mimic endogenous pain control mechanisms.

The APS authors cited a recent survey of neurologists in which the most transformative pain drug of the past decade is considered to be the triptan class for migraines. “The triptan family of drugs was identified in preclinical studies searching for compounds with a specific mechanism, and it represents a clear success in translating basic science discoveries into human therapies,” said lead author Robert Gereau, PhD, professor of anesthesiology and director, Washington University Pain Center, St. Louis. “More discoveries like this are badly needed.”

Gereau said despite past successes, research investment in basic pain research in government, academia, and the industry is falling, even though chronic pain is a complex set of conditions. “New therapeutic interventions can be discovered through basic science advances that elucidate the fundamentals of the biology of pain and its development into a chronic pain disease state,” explained Gereau. “We must increase efforts to identify new targets for the development of novel pain therapies.

Currently Available Treatments Could Be Safer, More Effective

APS believes the nation’s pain research priorities also should involve studies to investigate how to better implement treatments proven to be efficacious and promote access to interdisciplinary pain treatment programs to improve the quality of life for persons with chronic pain.

“This will require studies to identify key barriers to implementing therapies that have been shown to be effective but are not commonly prescribed. Paramount in optimizing the use of and access to effective pain treatments is identifying which of the available treatments are most effective in various patient populations for the management of chronic pain,” said Fillingim.

He added that limited funding allocated for pain research has hampered clinicians’ ability to provide optimal, evidence-based care for pain, and also has contributed to faulty prescribing and misuse of pain medications. “The dramatic increase in prescribing opioids in the last 20 years occurred against a backdrop of limited availability of alternative pain treatments and insufficient data regarding the long-term safety and efficacy of opioid therapy for chronic non-cancer pain,” Fillingim said.

Lack of Public Awareness Hampers Progress

A major barrier for implementing the pain research agenda is an alarming lack of public awareness about the magnitude of the pain problem in the United States. A recent Research America poll showed that just 18% of respondents identified chronic pain as a major public health problem. Far less prevalent conditions, such as Alzheimer’s, were much more frequently described as serious public health conditions.

“Lack of public awareness not only contributes to continued lack of federal funding but also has a negative impact on potential private and philanthropic support for pain research and treatment,” said Gereau.

“Addressing the enormous burden of chronic pain requires a fundamental change in the ways physicians, policy makers, and society view the problem of pain. Achieving this change in beliefs and attitudes will require significant educational outreach for clinicians, policy makers, and the public,” he added.

PAIN Highlights

The following highlights summarize selected articles from PAIN (Volume 155, Issue 12, December 2014 Issue).

Efficacy of Memantine in the Treatment of Fibromyalgia: A Double-Blind, Randomized, Controlled Trial with 6-Month Follow-Up
Bárbara Olivan-Blázquez, Paola Herrera-Mercadal, Marta Puebla-Guedea, Mari-Cruz Pérez-Yus, Eva Andrés, Nicolas Fayed, Yolanda López-Del-Hoyo, Rosa Magallon, Miquel Roca, and Javier Garcia-Campayo; Department of Psychology and Sociology, University of Zaragoza, Spain; Preventative Activities and Health Promotion Network (REDIAPP) (RD06/0018), Instituto Aragonés de Ciencias de la Salud (IACS), Aragón, Spain; Unidad Epidemiología Clínica, Hospital 12 de Octubre, Autonomous University of Madrid, CIBER Epidemiology and Public Health, Madrid, Spain; Department of Radiology, Hospital Quirón, Zaragoza, Spain; Primary Health Center Arrabal, Zaragoza, Spain; Institut Universitari d’Investigació en Ciències de la Salut (IUNICS), University of Balearic Islands, Palma de Mallorca, Spain; Department of Psychiatry, Miguel Servet University Hospital, Zaragoza, Spain

Pain is the most common and disabling symptom of fibromyalgia (FM). Evidence suggests that glutamate, an excitatory neurotransmitter in the central nervous system, may play a part in the pathophysiology of FM because its concentration is elevated in the insula, hippocampus, and posterior cingulate cortex. Some investigators have suggested that glutamate-blocking drugs such as memantine may be useful in the treatment of FM by reducing the harmful effects that result from excessively high levels of brain glutamate found in this condition. Memantine has been used to treat Parkinson’s disease, spasticity, convulsions, vascular dementia, and Alzheimer’s disease, and has an excellent clinical safety record spanning more than 20 years.

The aim of this study was to evaluate the efficacy of memantine to increase pain thresholds and decrease pain perception in patients with fibromyalgia. The secondary objectives were to evaluate the efficacy of memantine on quality of life and in the treatment of other symptoms of fibromyalgia such as cognitive function, health status, clinical global impression, anxiety, and depression.

A double-blind, parallel, randomized, controlled trial included 63 patients with FM who were recruited from primary healthcare centers in Zaragoza, Spain. Memantine was administered at doses of 20 mg/d after 1 month of titration. Assessments were carried out at baseline, posttreatment, and 3- and 6-month follow-up. This study provided preliminary evidence of the utility of memantine for the treatment of many clinical domains in FM.

Memantine increased pain thresholds and decreased pain perception for these patients. Investigators expect the benefits of memantine in FM treatment to be threefold: neuroprotection via antagonism of N-methyl-D-aspartate receptors, analgesia through the normalization of dysregulated pronociceptive and antinociceptive pathways, and enhanced analgesia and prevention. Cognitive impairment in fibromyalgia seems to be strongly related to depression and pain, and the improvement that memantine produces regarding these two variables may partially explain its efficacy on cognition.

Transcutaneous Electrical Nerve Stimulation for the Control of Pain During Rehabilitation After Total Knee Arthroplasty: A Randomized, Blinded, Placebo-Controlled Trial
Barbara A. Rakel, M. Bridget Zimmerman, Katharine Geasland, Jennie Embree, Charles R. Clark, Nicolas O. Noiseux, John J. Callaghan, Keela Herr, Deirdre Walsh, and Kathleen A. Sluka; The University of Iowa College of Nursing, Iowa City, Iowa; Department of Biostatistics, The University of Iowa College of Public Health, Iowa City; Department of Orthopedics and Rehabilitation, The University of Iowa College of Medicine, Iowa City; School of Health Sciences, University of Ulster, Northern Ireland, United Kingdom; Department of Physical Therapy and Rehabilitation Science, The University of Iowa College of Medicine, Iowa City

Total knee arthroplasty (TKA) is commonly performed to reduce pain and improve function for patients with degenerative knee osteoarthritis. However, rehabilitation after this procedure can be painful, particularly during movements such as flexion/extension of the knee joint, and severe pain during these activities has been associated with poor functional recovery. Transcutaneous electrical nerve stimulation (TENS) is a potentially efficacious pain treatment that is used as a supplement to pharmacologic analgesia during rehabilitation exercises to better control this severe pain.

This study evaluated the efficacy of TENS in reducing pain and hyperalgesia and increasing function after TKA. Investigators hypothesized that participants receiving TENS during rehabilitation after TKA would report significantly lower pain during range-of-motion (ROM) activity and walking, have less hyperalgesia around the surgical incision and at a distant site, and have better function than participants receiving placebo TENS or standard care. They also hypothesized that change in movement pain would differ based on psychological characteristics, pain catastrophizing, and treatment group.

Participants were randomly assigned to receive TENS, placebo TENS, or standard care (no TENS) as a supplement to standard pharmacologic analgesia for the control of pain during rehabilitation exercises after TKA. Findings revealed that adding TENS to routine pharmacologic analgesia significantly reduces movement pain during the immediate postoperative period compared to pharmacologic analgesia alone. There were no significant differences between TENS and placebo TENS, suggesting that the expectation of receiving additional pain relief through TENS had effects comparable to those of actually receiving TENS. Participants receiving placebo TENS, however, did not report significantly less pain than participants receiving standard care. A potentially important finding in this study was that participants receiving TENS who scored low on trait anxiety and pain catastrophizing had a significantly larger decrease in ROM pain than participants receiving TENS who scored high on these factors.

There were no group differences at 6 weeks after TKR, suggesting that TENS is not beneficial beyond the immediate postoperative period. The benefit of adding TENS may be most pronounced for patients who are not anxious or not likely to catastrophize their pain.

Pain Medicine Highlights

The following highlights summarize selected articles from Pain Medicine (Volume 15, Number 11, December 2014 Issue).

Health Care Utilization Among Veterans with Pain and Posttraumatic Stress Symptoms
Samantha D. Outcalt, Zhangsheng Yu, Helena Maria Hoen, Tenesha Marie Pennington, and Erin E. Krebs; Center of Excellence on Implementing Evidence-Based Practice, Roudebush VA Medical Center, Indianapolis, Ind.; Departments of Psychiatry and Biostatistics, Indiana University School of Medicine, Indianapolis; Department of Information Technology, Roudebush VA Medical Center, Indianapolis; Center for Chronic Disease Outcomes Research, Minneapolis VA Health Care System, Minneapolis, Minn.; Department of Medicine, University of Minnesota Medical School, Minneapolis

The rate of comorbidity between chronic pain and posttraumatic stress disorder (PTSD) is substantial, and patients with chronic pain or PTSD use healthcare services at disproportionally high rates. Additionally, chronic pain and PTSD commonly co-occur, especially among veterans.

This study was conducted to examine healthcare utilization among veterans with both chronic pain and PTSD symptoms. This retrospective cohort study involved 40,716 veterans in a VA regional network who sought care between January 1, 2002, and January 1, 2007. Veterans were categorized into pain-only, PTSD-only, and pain plus PTSD comparison groups. Investigators sought to explore the ways in which the comorbidity of PTSD and chronic pain affects veterans’ utilization of services in primary care, mental health, and specialty pain clinics and their use of medications. They hypothesized that veterans with both chronic pain and PTSD symptoms would have more visits to primary care and specialty pain clinics than veterans with pain alone; have fewer visits to mental health clinics than veterans with PTSD alone; and use opioids, benzodiazepines, non-opioid analgesics, and antidepressants for more months than veterans with either pain alone or PTSD alone.

Findings confirmed expectations that veterans with symptoms of both pain and PTSD use more healthcare services than those with pain only or PTSD only. Furthermore, the pattern of higher use among veterans with both pain and PTSD was consistent across multiple categories of outpatient visits and medication use. However, the hypothesis regarding mental health service use was not supported.

These findings of high healthcare use support the need for more integrated and streamlined treatments for this clinical population. The findings also are consistent with a study of Operation Enduring Freedom and Operation Iraqi Freedom veterans, which found high opioid prescription rates among those with comorbid pain and PTSD and high healthcare costs when traumatic brain injury was coupled with comorbid pain and PTSD.

The Avoidance of Activities Due to Fear of Falling Contributes to Sedentary Behavior Among Community-Dwelling Older Adults with Chronic Musculoskeletal Pain: A Multisite Observational Study
Brendon Stubbs, Sandhi Patchay, Andy Soundy, and Pat Schofield; School of Health and Social Care, Departments of Psychology and Nursing, University of Greenwich; Department of Physiotherapy, University of Birmingham, London, United Kingdom

This multisite observational study of 285 community-dwelling older adults had two aims, to establish if older adults with chronic musculoskeletal pain (CMP) spend significantly more time being sedentary than those of similar age and sex without CMP, and to investigate the factors that may contribute to increased sedentary behavior among older adults with CMP. Details regarding falls were collected and all participants completed the Brief Pain Inventory, a modified version of the Survey of Activities and Fear of Falling in Elderly Scale (mSAFFE), and the International Physical Activity Questionnaire. Data were analyzed with hierarchical regression analysis. It was hypothesized that pain interference, avoidance of activity because of fear of falling (FOF), and increased concerns about the FOF would significantly contribute to sedentary behavior among older adults with CMP over and above risk factors previously identified.

Investigators found that older adults with CMP spend approximately an additional 3.5 hours per day (more than 11 hours per day) being sedentary than a comparison group without CMP of similar age and sex. The hierarchical regression analysis demonstrated that the introduction of pain interference and avoidance of activities attributable to FOF (mSAFFE scores) significantly increased the variance in the amount of time older adults spend sitting each day. Within the fully adjusted model, mSAFFE scores were the largest significant predictor in sedentary behavior in older adults with CMP. Surprisingly, however, pain interference was not an independent predictor of sedentary behavior. The addition of the FOF scores did not increase the variance observed within the amount of time older adults with CMP were sedentary. These results provide provisional evidence that avoidance of activities because of FOF is an important and significant contributor to sedentary behavior among older adults with CMP.

Clinicians should consider addressing fear avoidance with patients while discussing their fall risk and mobility limitations. To help ensure success, this discussion should incorporate pain management strategies. Future research is required to prevent sedentary behavior and resulting avoidable death in older adults with CMP.

Important Dates

Young Investigator Awards

Applications Open: Tuesday January 6, 2015

Rita Allen Foundation Award in Pain

Deadline: Friday, January 16, 2015

Clinical and Basic Science Data Blitz

Submissions Open: February 2015

2015 Annual Scientific Meeting

May 13–16, 2015

Register Now

Call for Submissions

Do you have a topic that is relevant to APS members? Is there a member who is doing work that APS should spotlight? Is there a funding opportunity APS members need to know about? Please submit stories, events, and more to enews@americanpainsociety.org for consideration.