Chronic spinal pain and physical–mental comorbidity in the United States: results from the national comorbidity survey replication

Chronic Pain Types Differ in Their Reported Prevalence of Post -Traumatic Stress Disorder (PTSD) and There Is Consistent Evidence That Chronic Pain Is Associated with PTSD: An Evidence-Based Structured Systematic Review

Objectives

The hypotheses of this systematic review were the following: 1) Prevalence of post-traumatic stress disorder (PTSD) will differ between various types of chronic pain (CP), and 2) there will be consistent evidence that CP is associated with PTSD.

Methods

Of 477 studies, 40 fulfilled the inclusion/exclusion criteria of this review and were grouped according to the type of CP. The reported prevalence of PTSD for each grouping was determined by aggregating all the patients in all the studies in that group. Additionally all patients in all groupings were combined. Percentage of studies that had found an association between CP and PTSD was determined. The consistency of the evidence represented by the percentage of studies finding an association was rated according to the Agency for Health Care Policy and Research guidelines.

Results

Grouping PTSD prevalence differed ranging from a low of 0.69% for chronic low back pain to a high of 50.1% in veterans. Prevalence in the general population with CP was 9.8%. Of 19 studies, 16 had found an association between CP and PTSD (84.2%) generating an A consistency rating (consistent multiple studies). Three of the groupings had an A or B (generally consistent) rating. The veterans grouping received a C (finding inconsistent) rating.

Conclusion

The results of this systematic review confirmed the hypotheses of this review.

Evidence-Based Nonpharmacologic Strategies for Comprehensive Pain Care: The Consortium Pain Task Force White Paper

Medical pain management is in crisis; from the pervasiveness of pain to inadequate pain treatment, from the escalation of prescription opioids to an epidemic in addiction, diversion and overdose deaths. The rising costs of pain care and managing adverse effects of that care have prompted action from state and federal agencies including the DOD, VHA, NIH, FDA and CDC. There is pressure for pain medicine to shift away from reliance on opioids, ineffective procedures and surgeries toward comprehensive pain management that includes evidence-based nonpharmacologic options. This White Paper details the historical context and magnitude of the current pain problem including individual, social and economic impacts as well as the challenges of pain management for patients and a healthcare workforce engaging prevalent strategies not entirely based in current evidence. Detailed here is the evidence-base for nonpharmacologic therapies effective in postsurgical pain with opioid sparing, acute non-surgical pain, cancer pain and chronic pain. Therapies reviewed include acupuncture therapy, massage therapy, osteopathic and chiropractic manipulation, meditative movement therapies Tai chi and yoga, mind body behavioral interventions, dietary components and self-care/self-efficacy strategies. Transforming the system of pain care to a responsive comprehensive model necessitates that options for treatment and collaborative care must be evidence-based and include effective nonpharmacologic strategies that have the advantage of reduced risks of adverse events and addiction liability. The evidence demands a call to action to increase awareness of effective nonpharmacologic treatments for pain, to train healthcare practitioners and administrators in the evidence base of effective nonpharmacologic practice, to advocate for policy initiatives that remedy system and reimbursement barriers to evidence-informed comprehensive pain care, and to promote ongoing research and dissemination of the role of effective nonpharmacologic treatments in pain, focused on the short- and long-term therapeutic and economic impact of comprehensive care practices.

Effect of Inpatient Multicomponent Occupational Rehabilitation Versus Less Comprehensive Outpatient Rehabilitation on Sickness Absence in Persons with Musculoskeletal- or Mental Health Disorders: A Randomized Clinical Trial

Purpose To assess effects of an inpatient multicomponent occupational rehabilitation program compared to less comprehensive outpatient rehabilitation on sickness absence in persons with musculoskeletal- or mental health disorders. Methods Randomized clinical trial with parallel groups. Participants were individuals 18-60 years old on sick-leave for 2-12 months with a sick-leave diagnosis within the musculoskeletal, psychological or general and unspecified chapters of ICPC-2, identified in a national register. The inpatient program (4 + 4 days) consisted of Acceptance and Commitment Therapy (ACT), physical training and work-related problem-solving including creating a return to work plan and a workplace visit if considered relevant. The outpatient program consisted primarily of ACT (6 sessions during 6 weeks). Both programs were group based. Primary outcome was cumulated number of sickness absence days at 6 and 12 months follow-up. Secondary outcome was time until sustainable return to work. Results 168 individuals were randomized to the inpatient program (n = 92) or the outpatient program (n = 76). We found no statistically significant difference between the programs in median number of sickness absence days at 6 and 12 months follow-up. In the outpatient program 57% of the participants achieved sustainable return to work (median time 7 months), in the inpatient program 49% (log rank, p = 0.167). The hazard ratio for sustainable return to work was 0.74 (95% CI 0.48-1.32, p = 0.165), in favor of the outpatient program. Conclusions This study provided no support that the more comprehensive 4 + 4 days inpatient multicomponent occupational rehabilitation program reduced sickness absence compared to the outpatient rehabilitation program.

Protocol for the Individual Placement and Support (IPS) in Pain Trial: A randomized controlled trial investigating the effectiveness of IPS for patients with chronic pain

Background

Work disability involves large costs to the society as well as to the individual. Work disability is common among people with chronic pain conditions, yet few effective interventions exist. Individual Placement and Support (IPS) is an evidence-based work rehabilitation model originally developed to help people with severe mental illness obtain and maintain employment. The effectiveness of IPS for patients with severe mental illness is well documented, but the model has never before been tested for patients with chronic pain.

Methods/design

The aim of the IPS in Pain trial is to investigate the effectiveness of IPS as an integrated part of the interdisciplinary treatment for patients with chronic pain in a hospital outpatient clinic. The study is a randomized controlled trial comparing pain treatment with integrated IPS to treatment as usual in unemployed patients suffering from various chronic pain conditions. The primary outcome of the study is labor market participation during 12 months after enrollment, and secondary outcomes include physical and mental health and well-being, collected at baseline, 6, and 12 months. Finally, there will be an additional long-term follow-up for the primary outcome, which will be collected through a brief phone interview at 24 months.

Discussion

The IPS in Pain trial will be the first report of the effectiveness of the IPS model of supported employment applied in an outpatient setting for chronic pain patients. It will thus provide important information about the effectiveness of repurposing IPS to a new patient group in great need of job support.

Trial registration

Clinicaltrials.gov: NCT02697656. Registered January 15th, 2016.

Design of a study evaluating the effects, health economics, and stakeholder perspectives of a multi-component occupational rehabilitation program with an added workplace intervention - a study protocol

BACKGROUND

Recent research has suggested that interventions at the workplace might be the most potent ingredient in return to work interventions, but few studies have investigated the different effects of workplace interventions as part of occupational rehabilitation programs. The comprehensive design described in this article includes effect (on return to work and health outcomes), and health economic evaluations of a workplace intervention added to a multicomponent rehabilitation program. Qualitative and mixed method studies will investigate sick-listed persons', rehabilitation therapists' and employers' perspectives on the usability and outcomes of the rehabilitation program and the workplace intervention. The program and intervention are provided to patients with musculoskeletal, psychological or general and unspecified diagnoses. The program is multi-component and includes Acceptance and Commitment Therapy, physical exercise, patient education and creating a plan for increased work participation.

METHODS

Persons who are employed, aged from 18 to 60 years, with a current sick leave status of 50% or more and a diagnosis within the musculoskeletal, psychological or general and unspecified chapters of International Classification of Primary Care-2 (ICPC-2) will be recruited to a researcher-blinded parallel-group randomized controlled trial. All participants take part in an in-patient occupational rehabilitation program, while the intervention group also takes part in an intervention at the workplace. The effect and economic evaluation will investigate the effect of the added workplace intervention. The primary outcome measures will be time until full sustainable return to work and total number of sickness absence days in the 12 months after inclusion. Health economic evaluations will investigate the cost-effectiveness and cost-utility. Qualitative studies will investigate rehabilitation therapists' experiences with working towards return to work within an ACT-approach and stakeholders' experiences with the workplace intervention. A mixed methods study will combine quantitative and qualitative findings on the participants' expectations and motivation for return to work.

DISCUSSION

The outline of this comprehensive study could represent an important addition to the standard designs of return to work evaluation. The mixed methods design, with qualitative approaches as well as a rigorous randomized controlled trial, might prove useful to shed light on contextual factors.

TRIAL REGISTRATION

ClinicalTrials.gov : NCT02541890 . September 4, 2015.

Treating Depression with Transcutaneous Auricular Vagus Nerve Stimulation: State of the Art and Future Perspectives

Depression is a highly prevalent disorder, and its treatment is far from satisfactory. There is an urgent need to develop a new treatment for depression. Although still at its early stage, transcutaneous auricular vagus nerve stimulation (taVNS) has shown promising potential for treating depression. In this article, we first summarize the results of clinical studies on the treatment effect of taVNS on depression. Then, we re-analyze a previous study to identify the specific symptoms taVNS can relieve as indicated by subscores of the 24-item Hamilton Depression Scale in patients with depression. We found that taVNS can significantly reduce multiple symptoms of depression patients, including anxiety, psychomotor retardation, sleep disturbance, and hopelessness. Next, we pose several hypotheses on the mechanism of taVNS treatment of depression, including directly and indirectly modulating the activity and connectivity of key brain regions involved in depression and mood regulation; inhibiting neuro-inflammatory sensitization; modulating hippocampal neurogenesis; and regulating the microbiome-brain-gut axis. Finally, we outline current challenges and lay out the future directions of taVNS treatment of depression, which include (1) intensively comparing stimulation parameters and "dose effect" (treatment frequency and duration) to maximize the treatment effect of taVNS; (2) exploring the effect of taVNS on disorders comorbid with depression (such as chronic pain disorders, cardiovascular disorder, and autism) to provide new "two-for-one" treatment approaches for patients with these disorders; and (3) applying multiple scale methods to explore the underlying mechanism of taVNS.

A distinct biomarker of continuous transcutaneous vagus nerve stimulation treatment in major depressive disorder

BACKGROUND

Major depression is the fourth leading cause of disability worldwide and poses a socioeconomic burden worldwide. Transcutaneous vagus nerve stimulation (tVNS) is a promising noninvasive clinical device that may reduce the severity of major depression. However, the neural mechanism underlying continuous tVNS has not yet been elucidated.

OBJECTIVE

We aimed to explore the effect of hypothalamic subregion functional connectivity (FC) changes during continuous tVNS treatment on major depressive disorder (MDD) patients and to identify the potential biomarkers for treatment outcomes.

METHODS

Forty-one mild to moderate MDD patients were recruited and received either real or sham tVNS treatment for 4 weeks. We used a seed-to-whole brain approach to estimate the FC changes of hypothalamic subregions and their surrounding control areas during continuous tVNS treatment and explored their association with clinical outcome changes after 4 weeks of treatment.

RESULTS

Of the thirty-six patients that completed the study, those in the tVNS group had significantly lower scores on the 24-item Hamilton Depression (HAM-D) Rating Scale compared to the sham tVNS group after 4 weeks of treatment. The FC between the bilateral medial hypothalamus (MH) and rostral anterior cingulate cortex (rACC) was significantly decreased during tVNS but not during sham tVNS. The strength of this FC was significantly correlated with HAM-D improvements after 4 weeks of tVNS.

CONCLUSION

The FC between the bilateral MH and rACC may serve as a potential biomarker for the tVNS state and predict treatment responses. Our results provide insights into the neural modulation mechanisms of continuous tVNS and reveal a potential therapeutic target for MDD patients.

As if one pain problem was not enough: prevalence and patterns of coexisting chronic pain conditions and their impact on treatment outcomes

INTRODUCTION

The presence of multiple coexisting chronic pain (CP) conditions (eg, low-back pain and migraines) within patients has received little attention in literature. The goals of this observational longitudinal study were to determine the prevalence of coexisting CP conditions, identify the most frequent ones and patterns of coexistence, investigate the relationships among patients' biopsychosocial characteristics and number of CP conditions, and determine the impact of coexisting CP conditions on treatment response.

PATIENTS AND METHODS

A total of 3,966 patients attending multidisciplinary pain-treatment centers who were enrolled in the Quebec Pain Registry were included. Patients completed self-report and nurse-administered questionnaires before their first visit and 6 months later. Results were analyzed using descriptive statistics, factor and cluster analyses, negative binomials with log-link generalized linear models, and linear mixed-effect models.

RESULTS

A third of patients reported coexisting CP conditions. No specific patterns of comorbidities emerged. The presence of coexisting CP conditions was associated with longer pain duration, older age, being female, and poorer quality of life. The presence of more than one CP condition did not have a clinically significant impact on treatment responses.

DISCUSSION

The novelty of the study results relate to the heterogeneity that was found in the patterns of coexistence of CP conditions and the fact that having multiple CP conditions did not clinically impact treatment response. These results highlight the need for future research that examines causes of coexistence among CP conditions across the spectrum of CP, as opposed to focusing on specific conditions, and to examine whether multiple CP conditions impact on additional domains, such as treatment satisfaction. These results highlight the importance of studying the pathophysiological mechanisms underlying the development of coexisting CP conditions, in order eventually to prevent/minimize their occurrence and/or develop optimal treatment and management approaches.

Previous Mental Disorders and Subsequent Onset of Chronic Back or Neck Pain: Findings From 19 Countries

Associations between depression/anxiety and pain are well established, but its directionality is not clear. We examined the associations between temporally previous mental disorders and subsequent self-reported chronic back/neck pain onset, and investigated the variation in the strength of associations according to timing of events during the life course, and according to gender. Data were from population-based household surveys conducted in 19 countries (N = 52,095). Lifetime prevalence and age of onset of 16 mental disorders according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, and the occurrence and age of onset of back/neck pain were assessed using the Composite International Diagnostic Interview. Survival analyses estimated the associations between first onset of mental disorders and subsequent back/neck pain onset. All mental disorders were positively associated with back/neck pain in bivariate analyses; most (12 of 16) remained so after adjusting for psychiatric comorbidity, with a clear dose-response relationship between number of mental disorders and subsequent pain. Early-onset disorders were stronger predictors of pain; when adjusting for psychiatric comorbidity, this remained the case for depression/dysthymia. No gender differences were observed. In conclusion, individuals with mental disorder, beyond depression and anxiety, are at higher risk of developing subsequent back/neck pain, stressing the importance of early detection of mental disorders, and highlight the need of assessing back/neck pain in mental health clinical settings.

PERSPECTIVE

Previous mental disorders according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition are positively associated with subsequent back/neck pain onset, with a clear dose-response relationship between number of mental disorders and subsequent pain. Earlier-onset mental disorders are stronger predictors of subsequent pain onset, compared with later-onset disorders.

Threat Response System: Parallel Brain Processes in Pain vis-à-vis Fear and Anxiety

Pain is essential for avoidance of tissue damage and for promotion of healing. Notwithstanding the survival value, pain brings about emotional suffering reflected in fear and anxiety, which in turn augment pain thus giving rise to a self-sustaining feedforward loop. Given such reciprocal relationships, the present article uses neuroscientific conceptualizations of fear and anxiety as a theoretical framework for hitherto insufficiently understood pathophysiological mechanisms underlying chronic pain. To that end, searches of PubMed-indexed journals were performed using the following Medical Subject Headings' terms: pain and nociception plus amygdala, anxiety, cognitive, fear, sensory, and unconscious. Recursive sets of scientific and clinical evidence extracted from this literature review were summarized within the following key areas: (1) parallelism between acute pain and fear and between chronic pain and anxiety; (2) all are related to the evasion of sensory-perceived threats and are subserved by subcortical circuits mediating automatic threat-induced physiologic responses and defensive actions in conjunction with higher order corticolimbic networks (e.g., thalamocortical, thalamo-striato-cortical and amygdalo-cortical) generating conscious representations and valuation-based adaptive behaviors; (3) some instances of chronic pain and anxiety conditions are driven by the failure to diminish or block respective nociceptive information or unconscious treats from reaching conscious awareness; and (4) the neural correlates of pain-related conscious states and cognitions may become autonomous (i.e., dissociated) from the subcortical activity/function leading to the eventual chronicity. Identifying relative contributions of the diverse neuroanatomical sources, thus, offers prospects for the development of novel preventive, diagnostic, and therapeutic strategies in chronic pain patients.

Patient-Reported Outcome Measures: Utility for Predicting Spinal Surgery in an Integrated Spine Practice

BACKGROUND

For the majority of patients, spinal surgery is an elective treatment. The decision as to whether and when to pursue surgery is complicated and influenced by myriad factors, including pain intensity and duration, impact on functional activities, referring physician recommendation, and surgeon preference. By understanding the factors that lead a patient to choose surgery, we may better understand the decision-making process, improve outcomes, and provide more effective care.

OBJECTIVE

To investigate the relationship between patient-reported outcome measures (PROMs) at initial physiatry clinic consultation and subsequent decision to pursue surgical treatment. We hypothesized that measures of function, pain, and mental health might identify which patients eventually elect to pursue surgical management.

DESIGN

Retrospective chart review study.

SETTING

Physiatry spine clinic in a tertiary hospital.

PATIENTS

A total of 395 consecutive patients meeting our inclusion criteria were assessed for the presence of chronic pain, self-perceived disability, history of prior spinal surgery, and provision of chronic opioid therapy at the time of their initial visit to the integrated spine clinic.

METHODS

Retrospective chart review of all patients presenting to our spine clinic between August 1, 2014, and July 31, 2015, was performed. At the initial spine clinic consultation, patients were asked to complete the General Anxiety Disorder-7 (GAD-7), Patient Health Questionnaire-8 (PHQ-8), Oswestry Disability Index (ODI), and Patient-Reported Outcomes Measurement Information System (PROMIS) 10-item short-form questionnaire. The primary outcome was surgical intervention within 18 months from their first visit to the integrated spine clinic. We surveyed all patient records until February 2017 for CPT codes associated with spinal surgery, excluding from analysis those patients who were lost to follow-up within 1 year of the index visit. Analysis focused on the risk of spinal surgery, with data points treated as both continuous and categorical variables. We used logistic regression models to determine whether PROMs, either alone or in combination, predicted later decision to pursue surgical intervention.

MAIN OUTCOME MEASUREMENTS

Decision to pursue spinal surgery.

RESULTS

The baseline PROM scores spanning functional, mental health, and pain domains were collected for 94% of the patients presenting to our spine program during the interval of this study. In total, 146 patients were excluded because of missing patient-reported outcome data or less than 1 year of follow-up, leaving 395 patients for analysis. Of these, 40.3% were male with a median age of 58 years, 4.6% presented with a history of prior spinal surgery, and 3.8% were being treated with chronic opioids at their initial consultation. Male gender (P = .01) and older age (P = .05) were associated with subsequent surgery, but no relationship was observed between measured patient-reported outcomes and decision to undergo spinal surgery within 18 months of the index visit.

CONCLUSIONS

Contrary to our hypothesis, this analysis demonstrates that the PROMs evaluated in this study, alone are insufficient to identify patients who may elect to pursue spinal surgery. Male gender and increasing age correlate with decision for later spinal surgery.

LEVEL OF EVIDENCE

II.

A pilot study of the individual placement and support model for patients with chronic pain

Background

Individual Placement and Support (IPS) is an evidence-based work rehabilitation model with well-documented effects for people with mental illness. The model has, however, never been tested out for people with chronic pain. This pilot study aimed to investigate chronic pain patients’ experiences with the IPS job support model.

Methods

We recruited eight consecutive patients referred for various chronic pain conditions at a hospital outpatient pain clinic. They were offered IPS job support as an integrated part of their interdisciplinary pain rehabilitation. The patients’ experiences were investigated through semi-structured interviews 3 months after inclusion in the study.

Results

The participants reported mostly positive experiences with IPS. One participant dropped out of the study after deterioration of symptoms, while the remaining participants were satisfied with the intervention. Particular helpful aspects of the IPS intervention were the follow-up from the employment specialist, focus on competitive employment, focus on work despite pain complaints, reframing work into something positive, administrative support, and practice in writing applications. No participants reported adverse experiences from the IPS intervention. Within a 12-months time frame, 3 of the 8 participants gained competitive employment.

Conclusions

This is the first report of the IPS model of supported employment applied in an outpatient setting for chronic pain patients. The results suggest that IPS can be successfully integrated with interdisciplinary pain rehabilitation, and warrants large-scale testing in a randomized controlled trial.

Pain catastrophizing mediates the relationship between trait happiness and depressive symptoms in individuals with current pain

OBJECTIVE

There is an extensive relationship between chronic pain and depression; however, there is less research examining whether pain-specific factors, such as pain intensity, predict depression, above and beyond the role of normative factors, such as positive emotions. The current study characterized the independent contributions of pain intensity, pain catastrophizing, and a trait measure of happiness to self-rated depressive symptoms.

METHODS

We recruited and enrolled 70 volunteers across 3 groups of participants: two groups of patients with current low back pain (one group on opioids and one group opioid-naïve), and individuals in a methadone maintenance treatment program.

RESULTS

Of note, participants reporting concurrent opioid use reported significantly higher levels of depressive symptomatology, although study groups did not differ on any other clinical variables. In our path model, we failed to find direct relationships between pain (intensity or duration) and either trait happiness or depressive symptoms (p > .05). However, our analysis did reveal that individuals with chronic back pain who reported higher levels of trait happiness reported lower levels of depressive symptomatology; this effect was significantly mediated by lower levels of pain catastrophizing (standardized ab = -.144, p = .002).

CONCLUSION

Our analysis suggests that trait happiness, while unrelated to ongoing pain, may predict a decreased vulnerability to depressive symptoms in individuals with chronic pain, which may operate via lower levels of pain catastrophizing.

Affect and Low Back Pain: More to Consider Than the Influence of Negative Affect Alone

OBJECTIVES

Affect balance style, a measure of trait positive affect (PA) and negative affect (NA), is predictive of pain and functioning in fibromyalgia and healthy individuals. The purpose of this study was to evaluate the distribution of affect balance styles and the relationship between these styles and clinical factors in low back pain.

METHODS

In this cross-sectional study, patients with low back pain (N=443) completed questionnaires and were categorized as having 1 of 4 distinct affect balance styles: Healthy (high levels of PA and low levels of NA), Low (low PA/low NA), Reactive (high PA/high NA), and Depressive (low PA/high NA). Comparisons between groups were made in regard to pain, functioning, and psychiatric comorbidity.

RESULTS

High NA was observed in 63% (n=281), whereas low PA was present in 81% (n=359). We found that having a Depressive style was associated with greater pain severity, increased odds for comorbid fibromyalgia, and worse functioning compared with having a Healthy or Low style. Yet, those with a Low style were at increased risk for depression compared with a Healthy style, whereas patients with a Reactive style had similar levels of pain, functioning, and depression as those with a Healthy affective style.

CONCLUSIONS

Our study revealed that there are important differences between trait affect balance styles in regard to pain, mood, and functioning in low back pain. Findings related to Reactive and Low affective styles suggest that relationships between affect, pain, and disability in low back pain extend beyond considering NA alone.

Rationale for and approach to preoperative opioid weaning: a preoperative optimization protocol

The practice of chronic opioid prescription for chronic non-cancer pain has come under considerable scrutiny within the past several years as mounting evidence reveals a generally unfavorable risk to benefit ratio and the nation reels from the grim mortality statistics associated with the opioid epidemic. Patients struggling with chronic pain tend to use opioids and also seek out operative intervention for their complaints, which combination may be leading to increased postoperative "acute-on-chronic" pain and fueling worsened chronic pain and opioid dependence. Besides worsened postoperative pain, a growing body of literature, reviewed herein, indicates that preoperative opioid use is associated with significantly worsened surgical outcomes, and severely increased financial drain on an already severely overburdened healthcare budget. Conversely, there is evidence that preoperative opioid reduction may result in substantial improvements in outcome. In the era of accountable care, efforts such as the Enhanced Recovery After Surgery (ERAS) protocol have been introduced in an attempt to standardize and facilitate evidence-based perioperative interventions to optimize surgical outcomes. We propose that addressing preoperative opioid reduction as part of a targeted optimization approach for chronic pain patients seeking surgery is not only logical but mandatory given the stakes involved. Simple opioid reduction/abstinence however is not likely to occur in the absence of provision of viable and palatable alternatives to managing pain, which will require a strong focus upon reducing pain catastrophization and bolstering self-efficacy and resilience. In response to a call from our surgical community toward that end, we have developed a simple and easy-to-implement outpatient preoperative optimization program focusing on gentle opioid weaning/elimination as well as a few other high-yield areas of intervention, requiring a minimum of resources.

Cardioprotection induced in a mouse model of neuropathic pain via anterior nucleus of paraventricular thalamus

Myocardial infarction is the leading cause of death worldwide. Restoration of blood flow rescues myocardium but also causes ischemia-reperfusion injury. Here, we show that in a mouse model of chronic neuropathic pain, ischemia-reperfusion injury following myocardial infarction is reduced, and this cardioprotection is induced via an anterior nucleus of paraventricular thalamus (PVA)-dependent parasympathetic pathway. Pharmacological inhibition of extracellular signal-regulated kinase activation in the PVA abolishes neuropathic pain-induced cardioprotection, whereas activation of PVA neurons pharmacologically, or optogenetic stimulation, is sufficient to induce cardioprotection. Furthermore, neuropathic injury and optogenetic stimulation of PVA neurons reduce the heart rate. These results suggest that the parasympathetic nerve is responsible for this unexpected cardioprotective effect of chronic neuropathic pain in mice.

Various forms of preconditioning can prevent ischemic-reperfusion injury after myocardial infarction. Here, the authors show that in mice, the presence of chronic neuropathic pain can have a cardioprotective effect, and that this is dependent on neural activation in the paraventricular thalamus.

Effects of Inpatient Multicomponent Occupational Rehabilitation versus Less Comprehensive Outpatient Rehabilitation on Somatic and Mental Health: Secondary Outcomes of a Randomized Clinical Trial

Purpose To evaluate effects on somatic and mental health of a multicomponent inpatient occupational rehabilitation program compared to a less comprehensive outpatient program in individuals on sick leave for musculoskeletal complaints or mental health disorders. Methods A randomized clinical trial with parallel groups. Participants were individuals on sick-leave for 2-12 months with a sick-leave diagnosis within the musculoskeletal, psychological or general and unspecified chapters of ICPC-2. Potential participants were identified in the Social Security System Registry. The multicomponent inpatient program (4 + 4 days) consisted of Acceptance and Commitment Therapy, physical training and work-related problem-solving including creating a return to work plan and a workplace visit if considered relevant. The comparative outpatient program consisted primarily of ACT (6 sessions during 6 weeks). Self-reported health-related quality of life, subjective health complaints, pain and anxiety and depression symptoms were assessed up to 12 months after the program. Results 168 individuals were randomized to the multicomponent inpatient program (n = 92) or the outpatient program (n = 76). Linear mixed models showed no statistically significant differences between the programs, except for slightly more reduced pain after the outpatient program. Conclusions This study presents no support that a 4 + 4 days multicomponent inpatient rehabilitation program is superior to a less comprehensive outpatient program, in improving health outcomes.

Alcohol and Drug Use and Aberrant Drug-Related Behavior Among Patients on Chronic Opioid Therapy

OBJECTIVE

To better identify individuals on chronic opioid therapy (COT) at high risk for aberrant-drug related behavior (ADRB). We examine whether patients with low level alcohol and drug use have similar characteristics to those with alcohol and drug disorders. We then examined the relationship of alcohol and drug use to ADRBs among COT patients.

METHODS

The sample was 972 randomly selected COT patients (age 21-80 years old) from a large health system in Northern California, USA, and interviewed in 2009. Logistic regression models were used to model the dependent variables of: alcohol use, illicit drug use, alcohol disorders, illicit drug disorders, and ADRBs.

RESULTS

The odds of daily/weekly alcohol use were lower for those with a high daily opioid dose (120+ mg/day vs. <20 mg/day) (OR = 0.32, p < 0.010). Illicit drug disorders were associated with depression (OR = 2.31, p < .001) and being on a high daily opioid dose (OR = 5.51, p < .01). Participants with illicit drug use had higher odds of giving (OR = 2.57, p < 0.01) and receiving opioids from friends or family (OR = 3.25, p < 0.001), but disorder diagnoses were not associated with ADRBs.

CONCLUSIONS

Findings reinforce that illicit drug use should be of high concern to clinicians prescribing opioids, and suggest it should be considered separately from alcohol use and alcohol disorders in the evaluation of ADRBs. Frequent alcohol use is low, but not uncommon, and suggests a need to discuss specific issues regarding safe use of opioids among persons who use alcohol that may differ from their risk of drug use.

Safety and effectiveness of once-daily Hysingla extended-release tablets in patients with baseline depression or anxiety

AIM

Long-term safety and effectiveness of a once-daily, single-entity, extended-release formulation of hydrocodone bitartrate (HYD) for the treatment of moderate to severe noncancer and nonneuropathic pain among patients with and without concurrent depression/anxiety at baseline.

MATERIALS & METHODS

Post hoc analysis.

RESULTS

HYD demonstrated a safety profile consistent with μ-opioid agonists: Serious adverse events in 12% patients with depression/anxiety including four deaths; 6% without depression/anxiety including one death. All pain scores declined by ≥2 points and mean daily HYD dose remained stable in both subgroups.

CONCLUSION

More serious adverse events occurred among patients with comorbid depression/anxiety at baseline than among those without. HYD provided stable and effective analgesia for 52 weeks among chronic pain patients with and without comorbid depression/anxiety at baseline.

Relationships between components of emotional intelligence and physical pain in alcohol-dependent patients

PURPOSE

Chronic pain is a significant comorbidity in individuals with alcohol dependence (AD). Emotional processing deficits are a substantial component of both AD and chronic pain. The aim of this study was to analyze the interrelations between components of emotional intelligence and self-reported pain severity in AD patients.

PATIENTS AND METHODS

A sample of 103 participants was recruited from an alcohol treatment center in Warsaw, Poland. Information concerning pain level in the last 4 weeks, demographics, severity of current anxiety and depressive symptoms, as well as neuroticism was obtained. The study sample was divided into "mild or no pain" and "moderate or greater pain" groups.

RESULTS

In the logistic regression model, across a set of sociodemographic, psychological, and clinical factors, higher emotion regulation and higher education predicted lower severity, whereas increased levels of anxiety predicted higher severity of self-reported pain during the previous 4 weeks. When the mediation models looking at the association between current severity of anxiety and depressive symptoms and pain severity with the mediating role of emotion regulation were tested, emotion regulation appeared to fully mediate the relationship between depression severity and pain, and partially the relationship between anxiety severity and pain.

CONCLUSION

The current findings extend previous results indicating that emotion regulation deficits are related to self-reported pain in AD subjects. Comprehensive strategies focusing on the improvement of mood regulation skills might be effective in the treatment of AD patients with comorbid pain symptoms.

Identifying heavy health care users among primary care patients with chronic non-cancer pain

Objective: The objective of this study was to identify biopsychosocial factors predicting primary care chronic non-cancer pain (CNCP) patients' risk of being heavy health care users. Methods: Patients reporting moderate to severe CNCP for at least 6 months with an active analgesic prescription from a primary care physician were recruited in community pharmacies. Recruited patients completed questionnaires documenting biopsychosocial characteristics. Using administrative databases, direct costs were estimated for health care services used by each patient in the year preceding and following the recruitment. Heavy health care users were defined as patients in the highest annual direct health care costs quartile. Logistic multivariate regression models using the Akaike information criterion were developed to identify predictors of heavy health care use. Results: The median annual direct health care cost incurred by heavy health care users (n = 63) was CAD (Canadian dollars) 7627, versus CAD 1554 for standard health care users (n = 188). The final predictive model of the risks of being a heavy health care user included pain located in the lower body (odds ratio [OR] = 3.03; 95% confidence interval [CI], 1.20-7.65), pain-related disability (OR = 1.24; 95% CI, 1.03-1.48), and health care costs incurred in the year prior to recruitment (OR = 17.67; 95% CI, 7.90-39.48). Variables in the model also included sex, comorbidity, patients' depression level, and attitudes toward medical pain cure. Conclusion: Patients suffering from CNCP in the lower body and showing greater disability were more likely to be heavy health care users, even after adjusting for previous-year direct health care costs. Improving pain management for these patients could have positive impacts on health care use and costs.

The influence of multisite pain and psychological comorbidity on prognosis of chronic low back pain: longitudinal data from the Norwegian HUNT Study

OBJECTIVES

This study aimed to investigate the prospective influence of multisite pain, depression, anxiety, self-rated health and pain-related disability on recovery from chronic low back pain (LBP).

SETTING

The data is derived from the second (1995-1997) and third (2006-2008) wave of the Nord-Trøndelag Health Study (HUNT) in Norway.

PARTICIPANTS

The study population comprises 4484 women and 3039 men in the Norwegian HUNT Study who reported chronic LBP at baseline in 1995-1997.

PRIMARY OUTCOME MEASURES

The primary outcome was recovery from chronic LBP at the 11-year follow-up. Persons not reporting pain and/or stiffness for at least three consecutive months during the last year were defined as recovered. A Poisson regression model was used to estimate adjusted risk ratios (RRs) with 95% CIs.

RESULTS

At follow-up, 1822 (40.6%) women and 1578 (51.9%) men reported recovery from chronic LBP. The probability of recovery was inversely associated with number of pain sites (P-trend<0.001). Compared with reporting 2-3 pain sites, persons with only LBP had a slightly higher probability of recovery (RR 1.10, 95% CI 0.98 to 1.22 in women and RR 1.10, 95% CI 1.01 to 1.21 in men), whereas people reporting 6-9 pain sites had substantially lower probability of recovery (RR 0.58, 95% CI 0.52 to 0.63 in women and RR 0.70, 95% CI 0.63 to 0.79 in men). Poor/not so good self-rated general health, symptoms of anxiety and depression, and pain-related disability in work and leisure were all associated with reduced probability of recovery, but there was no statistical interaction between multisite pain and these comorbidities.

CONCLUSIONS

Increasing number of pain sites was inversely associated with recovery from chronic LBP. In addition, factors such as poor self-rated health, psychological symptoms and pain-related disability may further reduce the probability of recovery from chronic LBP.

Sensitivity to Pain Traumatization Scale: development, validation, and preliminary findings

Background

This article reports three studies describing the development and validation of the 12-item Sensitivity to Pain Traumatization Scale (SPTS-12). SPT refers to the anxiety-related cognitive, emotional, and behavioral reactions to pain that resemble the features of a traumatic stress reaction.

Methods

In Study 1, a preliminary set of 79 items was administered to 116 participants. The data were analyzed by using combined nonparametric and parametric item response theory resulting in a 12-item scale with a one-factor structure and good preliminary psychometric properties. Studies 2 and 3 assessed the factor structure and psychometric properties of the SPTS-12 in a community sample of 823 participants (268 with chronic pain and 555 pain-free) and a clinical sample of 345 patients (126 with chronic post-surgical pain, 92 with other nonsurgical chronic pain, and 127 with no chronic pain) at least 6 months after undergoing coronary artery bypass graft surgery, respectively.

Results

The final SPTS-12 derived from Study 1 comprised 12 items that discriminated between individuals with different levels of SPT, with the overall scale showing good to very good reliability and validity. The results from Studies 2 and 3 revealed a one-factor structure for chronic pain and pain-free samples, excellent reliability and concurrent validity, and moderate convergent and discriminant validity.

Conclusion

The results of the three studies provide preliminary evidence for the validity and reliability of the SPTS-12.

The triallelic serotonin transporter gene polymorphism is associated with depressive symptoms in adults with chronic pain

BACKGROUND

The serotonin (5-HT) transporter-linked polymorphic region (5-HTTLPR) moderates the relationship between stressful life events and depression. Given the high prevalence of depression in chronic pain, the primary aim of this preliminary study was to investigate the associations between the 5-HTTLPR and the severity of depressive symptoms in a cohort of adults with chronic pain.

METHODS

Adults with chronic pain who were consecutively admitted to an outpatient pain rehabilitation program and met inclusion criteria were recruited for study participation (n=277). Individuals were genotyped for the 5-HTTLPR (including rs25531) and categorized as high, intermediate, or low expressors of the 5-HT transporter. The severity of depressive symptoms at admission was measured by using the Center for Epidemiologic Depression scale (CES-D).

RESULTS

The distribution of the high-, intermediate-, and low-expressing genotypes was 61 (22%), 149 (54%), and 67 (24%), respectively. The Hardy-Weinberg P-value was 0.204, which indicated no departure from equilibrium. A main effect of 5-HTTLPR was observed for depressive symptoms (P=0.040) where Center for Epidemiologic Depression scale (CES-D) scores were significantly greater in the low-expressing group compared to the high- (P=0.019) and intermediate (P=0.029)-expressing groups. In multivariate multinomial logistic regression analysis adjusted for age, sex, pain severity, pain catastrophizing, and pain anxiety, greater CES-D scores were significantly associated with the 5-HTTLPR low-expressing group compared to the high-expressing group (P=0.023), but not for the low-expressing group compared to the intermediate-expressing group (P=0.056).

CONCLUSION

These preliminary findings suggest that the triallelic 5-HTTLPR could influence the severity of depressive symptoms in adults with chronic pain. Individuals with chronic pain may be particularly vulnerable to the moderating effects of 5-HTTLPR due to high levels of pain-related stress that are inherently present in this population.

Cannabis and Pain: A Clinical Review

Introduction: Cannabis has been used for medical purposes across the world for centuries. As states and countries implement medical and recreational cannabis policies, increasing numbers of people are using cannabis pharmacotherapy for pain. There is a theoretical rationale for cannabis' efficacy for pain management, although the subjective pain relief from cannabis may not match objective measurements of analgesia. As more patients turn to cannabis for pain relief, there is a need for additional scientific evidence to evaluate this increase. Materials and Methods: Research for this review was performed in the PubMed/National Library of Medicine database. Discussion: Preclinical studies demonstrate a narrow therapeutic window for cannabis as pharmacotherapy for pain; the body of clinical evidence for this indication is not as extensive. A recent meta-analysis of clinical trials of cannabis and cannabinoids for pain found modest evidence supporting the use of cannabinoid pharmacotherapy for pain. Recent epidemiological studies have provided initial evidence for a possible reduction in opioid pharmacotherapy for pain as a result of increased implementation of medical cannabis regimens. Conclusion: With increased use of medical cannabis as pharmacotherapy for pain comes a need for comprehensive risk-benefit discussions that take into account cannabis' significant possible side effects. As cannabis use increases in the context of medical and recreational cannabis policies, additional research to support or refute the current evidence base is essential to attempt to answer the questions that so many healthcare professionals and patients are asking.

Prevalence and factors associated with low back pain in elderly registered in the Family Health Strategy

Abstract Introduction: Low back pain has varied etiology and complex discussed and can be triggered by various factors. Objective: Was to assess the prevalence of low back pain in individuals 60 years or more of the areas of the Family Health Strategy “Vila Sao Paulo” in the city of Bauru, São Paulo, and its association with demographic and socioeconomic variables, relating to work, lifestyle and morbidity. Methods: We conducted a cross-sectional study with 363 elderly sampled by the technique of two-stage cluster, which were interviewed at home using a multidimensional instrument (demographic, socio-economic, featuring work; lifestyle; morbidity) and the Nordic questionnaire. Conducted descriptive analysis, bivariate and Poisson regression. Results: It was noted more frequently in the elderly age group between 60 and 69 years old, married, with low education and income from two to five. The prevalence of low back pain was 55.8% of elderly patients studied, 52.2% in men and 47.8% women and, the variables load and carry weight (p = 0.001) and the number of diseases referred to (p = 0.04) showed association with the presence of low back pain. Conclusion: The elderly respondents show a high prevalence of low back pain associated with the loading and transport weight and the number of diseases referred.

The immediate cardiovascular response to joint mobilization of the neck - A randomized, placebo-controlled trial in pain-free adults

BACKGROUND

Some normotensive patients can have a spike in resting systolic blood pressure (SBP) in response to acute neck pain. Applying the typical dosage of mobilization may potentially result in a sympatho-excitatory response, further increasing resting SBP. Therefore, there is a need to explore other dosage regimens that could result in a decrease in SBP.

OBJECTIVES

To compare the blood pressure (BP) and heart rate (HR) response of pain-free, normotensive adults when receiving unilateral posterior-to-anterior mobilization (PA) applied to the neck versus its corresponding placebo (PA-P).

STUDY DESIGN

Double-Blind, Randomized Clinical Trial.

METHODS

44 (18 females) healthy, pain-free participants (mean age, 23.8 ± 3.04 years) were randomly allocated to 1 of 2 groups. Group 1 received a PA-P in which light touch was applied to the right 6th cervical vertebra. Group 2 received a PA to the same location. BP and HR were measured prior to, during, and after the application of PA or PA-P. A mixed-effect model of repeated measure analysis was used for statistical analysis.

RESULTS

During-intervention, the PA group had a significant reduction in SBP, while the placebo group had an increase in SBP. The change in SBP during-intervention was significantly different between the PA and the placebo group (p-value = 0.003). There were no significant between-group differences found for HR and diastolic BP (DBP). The overall group-by-time interaction was statistically significant for SBP (p-value = 0.01).

CONCLUSIONS

When compared to placebo, the dosage of applied PA resulted in a small, short-lived drop in SBP not exceeding the minimal detectable change. Trial registered at Germanctr.de (DRKS00005095).

Morphine responsiveness to thermal pain stimuli is aging-associated and mediated by dopamine D1 and D3 receptor interactions

Morphine actions involve the dopamine (DA) D1 and D3 receptor systems (D1R and D3R), and the responses to morphine change with age. We here explored in differently aged wild-type (WT) and D3R knockout mice (D3KO) the interactions of the D1R/D3R systems with morphine in vivo at three different times of the animals' lifespan (2months, 1year, and 2years). We found that: (1) thermal pain withdrawal reflexes follow an aging-associated phenotype, with relatively longer latencies at 2months and shorter latencies at 1year, (2) over the same age range, a dysfunction of the D3R subtype decreases reflex latencies more than aging alone, (3) morphine altered reflex responses in a dose-dependent manner in WT animals and changed at its higher dose the phenotype of the D3KO animals from a morphine-resistant state to a morphine-responsive state, (4) block of D1R function had an aging-dependent effect on thermal withdrawal latencies in control animals that, in old animals, was stronger than that of low-dose morphine. Lastly, (5) block of D1R function in young D3KO animals mimicked the behavioral phenotype observed in the aged WT. Our proof-of-concept data from the rodent animal model suggest that, with age, block of D1R function may be considered as an alternative to the use of morphine, to modulate the response to painful stimuli.

Risk Factors for Postoperative Pain Intensity in Patients Undergoing Lumbar Disc Surgery: A Systematic Review

OBJECTIVES

Pain relief has been shown to be the most frequently reported goal by patients undergoing lumbar disc surgery. There is a lack of systematic research investigating the course of postsurgical pain intensity and factors associated with postsurgical pain. This systematic review focuses on pain, the most prevalent symptom of a herniated disc as the primary outcome parameter. The aims of this review were (1) to examine how pain intensity changes over time in patients undergoing surgery for a lumbar herniated disc and (2) to identify socio-demographic, medical, occupational and psychological factors associated with pain intensity.

METHODS

Selection criteria were developed and search terms defined. The initial literature search was conducted in April 2015 and involved the following databases: Web of Science, Pubmed, PsycInfo and Pubpsych. The course of pain intensity and associated factors were analysed over the short-term (≤ 3 months after surgery), medium-term (> 3 months and < 12 months after surgery) and long-term (≥ 12 months after surgery).

RESULTS

From 371 abstracts, 85 full-text articles were reviewed, of which 21 studies were included. Visual analogue scales indicated that surgery helped the majority of patients experience significantly less pain. Recovery from disc surgery mainly occurred within the short-term period and later changes of pain intensity were minor. Postsurgical back and leg pain was predominantly associated with depression and disability. Preliminary positive evidence was found for somatization and mental well-being.

CONCLUSIONS

Patients scheduled for lumbar disc surgery should be selected carefully and need to be treated in a multimodal setting including psychological support.

A randomized controlled trial of brief Somatic Experiencing for chronic low back pain and comorbid post-traumatic stress disorder symptoms

Background: It is well documented that comorbid post-traumatic stress disorder (PTSD) in chronic pain is associated with a more severe symptom profile with respect to pain, disability and psychological distress. However, very few intervention studies exist targeting both PTSD and pain. The current study is the first randomized controlled trial evaluating the effect of the body-oriented trauma approach of Somatic Experiencing (SE) for comorbid PTSD and low back pain. Although the method is well recognized by clinicians and widely used, SE still needs to be tested in a randomized clinical trial in comparison with an active control group. Objective: The aim of the current study was to compare the effect of an SE intervention in addition to treatment-as-usual (TAU) for patients with chronic low back pain and comorbid PTSD compared to TAU alone. Method: The study was a two-group randomized controlled clinical trial. A cohort of patients (n = 1045) referred to a large Danish spine centre between February 2013 and October 2014 were screened for PTSD and randomized to either TAU (4-12 sessions of supervised exercises for low back pain) or TAU plus SE (6-12 sessions). In total, 91 patients fulfilled the inclusion criteria and volunteered to participate in the study. Treatment effects were evaluated by self-report questionnaires comparing baseline measures with 12-month follow-up measures. Results: The additional SE intervention significantly reduced the number of PTSD symptoms compared with TAU alone, corresponding to a large effect size. Also, fear of movement was significantly reduced (moderate effect size). Both groups achieved a large reduction in pain-catastrophizing, disability and pain. Conclusions: A brief additional SE intervention was found to have a significant effect on PTSD and fear of movement compared to TAU alone. However, the overall effect of SE was less than expected and the clinical importance of the effects can be questioned.

Clinical Significance of Pain at Hospital Discharge Following Traumatic Orthopedic Injury: General Health, Depression, and PTSD Outcomes at 1 Year

OBJECTIVES

The purpose of this study was to determine whether pain at hospital discharge is associated with general health and depression and posttraumatic stress disorder (PTSD) at 1 year following traumatic orthopedic injury.

MATERIALS AND METHODS

This study prospectively enrolled 213 patients, 19 to 86 years of age, admitted to an academic level 1 trauma center for surgical treatment of a traumatic lower-extremity or upper-extremity orthopedic injury. Pain at hospital discharge was measured with the Brief Pain Inventory. At 1-year follow-up, physical and mental health was assessed with the SF-12 and depressive and PTSD symptoms with the 9-item Patient Health Questionnaire (PHQ-9) and PTSD Checklist-Civilian Version (PCL-C), respectively. Cut-off scores of 10 on the PHQ-9 and 44 on the PCL-C classified patients as having depression or PTSD.

RESULTS

A total of 133 patients (62%) completed follow-up at 1 year. Responders and nonresponders did not differ significantly on baseline characteristics. Multivariable regression found that increased pain at discharge was significantly associated with depression (odds ratio=3.3; P<0.001) and PTSD (odds ratio=1.4; P=0.03) at 1 year, after controlling for age, education, injury severity score, and either depressive or PTSD symptoms at hospital discharge. Early postoperative pain was not a significant risk factor for long-term physical and mental health.

DISCUSSION

Findings highlight the importance of early screening for uncontrolled postoperative pain to identify patients at high risk for poor psychological outcomes and who could benefit from more aggressive pain management. Results suggest early interventions are needed to address pain severity in patients with orthopedic trauma.

Assessing the relationship between chronic pain and cardiovascular disease: A systematic review and meta-analysis

Background and Aims

Chronic pain is a potentially disabling condition affecting one in three people through impaired physical function and quality of life. While the psychosocial impact of chronic pain is already well established, little is known about the potential biological consequences. Chronic pain may be associated with an increased prevalence of cardiovascular disease, an effect that has been demonstrated across a spectrum of chronic pain conditions including low back pain, pelvic pain, neuropathic pain and fibromyalgia. The aim of this study was to review and summarize the evidence for a link between chronic pain and cardiovascular disease. We sought to clarify the nature of the relationship by examining the basis for a dose-response gradient (whereby increasing pain severity would result in greater cardiovascular disease), and by evaluating the extent to which potentially confounding variables may contribute to this association.

Methods

Major electronic databases MEDLINE, EMBASE, Psychinfo, Cochrane, ProQuest and Web of Science were searched for articles reporting strengths of association between chronic pain (pain in one or more body regions, present for three months or longer) and cardiovascular outcomes (cardiovascular mortality, cardiac disease, and cerebrovascular disease). Meta-analysis was used to pool data analysing the association between chronic pain and the three principal cardiovascular outcomes. The impact of pain severity, and the role of potentially confounding variables were explored narratively.

Results

The searches generated 11,141 studies, of which 25 matched our inclusion criteria and were included in the review. Meta-analysis (of unadjusted study outcomes) demonstrated statistically significant associations between chronic pain and mortality from cardiovascular diseases: pooled odds ratio 1.20, (95% confidence intervals 1.05–1.36); chronic pain and cardiac disease: pooled odds ratio 1.73 (95% confidence intervals 1.42–2.04); and chronic pain and cerebrovascular disease: pooled odds ratio 1.81 (95% confidence intervals 1.51–2.10). The systematic review also found evidence supporting a dose-response relationship, with greater pain intensity and distribution producing a stronger association with cardiovascular outcomes.

All of the included studies were based on observational data with considerable variation in chronic pain taxonomy, methodology and study populations. The studies took an inconsistent and incomplete approach in their adjustment for potentially confounding variables, making it impossible to pool data after adjustments for confounding variables, so it cannot be concluded that these associations are causal.

Conclusions

Our review supports a possible dose-response type of association between chronic pain and cardiovascular disease, supported by a range of observational studies originating from different countries. Such research has so far failed to satisfactorily rule out that the association is due to confounding variables. What is now needed are further population based longitudinal studies that are designed to allow more robust exploration of a cause and effect relationship.

Implications

Given the high prevalence of chronic pain in developed and developing countries our results highlight a significant, but underpublicized, public health concern. Greater acknowledgement of the potentially harmful biological consequences of chronic pain may help to support regional, national and global initiatives aimed at reducing the burden of chronic pain.

Illicit Substance Use in US Adults With Chronic Low Back Pain

STUDY DESIGN

A population-based cross-sectional survey.

OBJECTIVE

The aim of this study was to compare the prevalence of illicit drug use among US adults with and without chronic low back pain (cLBP).

SUMMARY OF BACKGROUND DATA

Although addictive medications, such as opioids and benzodiazepines, are frequently prescribed to patients with cLBP, little is known about illicit drug use among Americans with cLBP.

METHODS

We used data from the back pain survey, administered to a representative sample of US adults aged 20 to 69 years (N = 5103) during the 2009 to 2010 cycle of the National Health and Nutrition Examination Survey (NHANES). Participants with pain in the area between the lower posterior margin of the ribcage and the horizontal gluteal fold for at least 3 months were classified as having cLBP (N = 700). The drug use questionnaire was self-administered in a private setting, and included data on lifetime and current use of marijuana or hashish, cocaine, heroin, and methamphetamine. Chi-square tests, one-way analysis of variance, and logistic regression, adjusted for age, gender, race, and level of education, were used for comparisons.

RESULTS

About 46.5% of US adults with cLBP used marijuana versus 42% of those without cLBP [Adjusted odds ratio (aOR) 1.36, 95% confidence interval (95% CI) 1.06-1.74]. About 22% versus 14% used cocaine (aOR 1.80, 95% CI 1.45-2.24), 9% versus 5% used methamphetamine (aOR 2.03, 95% CI 1.30-3.16), and 5% versus 2% used heroin (aOR 2.43, 95% CI 1.44-4.11). Subjects with cLBP who reported lifetime illicit drug use were more likely to have an active prescription for opioid analgesics than those without illicit drug use history: 22.5% versus 15.3%, P = 0.018.

CONCLUSION

cLBP in community-based US adults was associated with higher odds of using marijuana, cocaine, heroin, and methamphetamine. Prescription opioid analgesic use was more common in cLBP sufferers with a history of illicit drug use.

LEVEL OF EVIDENCE

2.

Correspondence in Stakeholder Assessment of Health, Work Capacity and Sick Leave in Workers with Comorbid Subjective Health Complaints? A Video Vignette Study

Purpose The purpose of this study is to test if there is correspondence in stakeholders' assessments of health, work capacity and sickness certification in four workers with comorbid subjective health complaints based on video vignettes. Methods A cross sectional survey among stakeholders (N = 514) in Norway in 2009/2010. Logistic regression and multinomial logistic regression was used to obtain the estimated probability of stakeholders choosing 100 % sick leave, partial sick leave or work and the estimation of odds ratio of stakeholder assessment compared to the other stakeholders for the individual worker. Results The supervisors were less likely to assess poor health and reduced work capacity, and more likely to suggest partial sick leave and full time work compared to the GPs for worker 1. The public was less likely to assess comorbidity and reduced work capacity, and 6 and 12 times more likely to suggest partial sick leave and full time work compared to the GPs for worker 1. Stakeholders generally agreed in their assessments of workers 2 and 3. The public was more likely to assess poor health, comorbidity and reduced work capacity, and the supervisors more likely to assess comorbidity and reduced work capacity, compared to the GPs for worker 4. Compared to the GPs, all other stakeholders were less likely to suggest full time work for this worker. Conclusions Our results seem to suggest that stakeholders have divergent assessments of complaints, health, work capacity, and sickness certification in workers with comorbid subjective health complaints.

Protocol for the atWork trial: a randomised controlled trial of a workplace intervention targeting subjective health complaints

Background

Subjective health complaints, such as musculoskeletal and mental health complaints, have a high prevalence in the general population, and account for a large proportion of sick leave in Norway. It may be difficult to prevent the occurrence of subjective health complaints, but it may be possible to influence employees’ perception and management of these complaints, which in turn may have impact on sick leave and return to work after sick leave. Long term sick leave has many negative health and social consequences, and it is important to gain knowledge about effective interventions to prevent and reduce long term sick leave.

Methods/Design

This study is a cluster randomised controlled trial to evaluate the effect of the modified atWork intervention, targeting non-specific musculoskeletal complaints and mental health complaints. This intervention will be compared to the original atWork intervention targeting only non-specific musculoskeletal complaints. Kindergartens in Norway are invited to participate in the study and will be randomly assigned to one of the two interventions. Estimated sample size is 100 kindergartens, with a total of approximately 1100 employees. Primary outcome is sick leave at unit level, measured using register data from the Norwegian Labour and Welfare Administration. One kindergarten equals one unit, regardless of number of employees. Secondary outcomes will be measured at the individual level and include coping, health, job satisfaction, social support, and workplace inclusion, collected through questionnaires distributed at baseline and at 12 months follow up. All employees in the included kindergartens are eligible for participating in the survey.

Discussion

The effect evaluation of the modified atWork intervention is a large and comprehensive project, providing evidence-based information on prevention of long-term sick leave, which may be of considerable benefit both from a societal, organisational, and individual perspective.

Trial registration

Clinicaltrials.gov: NCT02396797. Registered March 23th, 2015.

Acute to chronic pain transition in extremity trauma: A narrative review for future preventive interventions (part 1)

BACKGROUND

Several studies have been conducted over the last decade that describe the issue of pain and prognostic factors of acute to chronic pain transition post extremity trauma (ET). However, no thorough interventions to prevent chronic pain development in ET patients have yet been proposed.

OBJECTIVES

This first part of a series of two articles aimed to provide a comprehensive analysis of literature on the epidemiology of pain post-ET, the impact of persistent pain on ET patients and the relevant biological transformations involved in acute to chronic pain transition. The second article will focus on risk and protective factors relating to chronic pain that could potentially assist in the development of preventive interventions.

METHODS

A narrative review of the literature was undertaken. Databases were searched to identify relevant studies and seminal works on the topics of interest.

RESULTS

The review revealed that acute pain converts to chronic pain in up to 86% of ET patients. Analysis of study findings also indicated that chronic pain interferes with activities of daily living and capacity to work. Weak associations between chronic pain and anxiety as well as depression have been demonstrated. Anxiety and depression have been identified as important predictors of chronic pain post-ET. Neuro-immunological transformations, genetics and an emotional shift in the brain circuitry involved in nociception have been shown to contribute to the transition towards chronic pain.

CONCLUSIONS

This narrative review supports the view that acute to chronic pain transition is a prevalent and significant issue post-ET. It also provides information about patients who present a higher risk of chronic pain and features that should be integrated in preventive interventions as well as methodological considerations pertaining to the evaluation of such interventions.

A randomized trial of a pain management intervention for adults receiving substance use disorder treatment

BACKGROUND AND AIMS

Chronic pain is difficult to treat in individuals with substance use disorders and, when not resolved, can have a negative impact on substance use disorder treatment outcomes. This study tested the efficacy of a psychosocial pain management intervention, ImPAT (improving pain during addiction treatment), that combines pain management with content related to managing pain without substance use.

DESIGN

Single-site, parallel-groups randomized controlled trial comparing ImPAT to a supportive psychoeducational control (SPC) condition; follow-up assessments occurred at 3, 6 and 12 months.

SETTING

The Ann Arbor VA Substance Use Disorder treatment program, USA.

PARTICIPANTS

Veterans Health Administration patients {n = 129; mean [standard deviation (SD)], age = 51.7 (9.5); 115 of 129 (89%) male; ImPAT (n = 65); SPC (n = 64)}.

INTERVENTION

ImPAT combines principles of cognitive-behavioral therapy and acceptance-based approaches to pain management with content related to avoiding the use of substances as a coping mechanism for pain. The SPC used a psychoeducational attention control treatment for alcoholism modified to cover other substances in addition to alcohol.

MEASUREMENTS

Primary: Pain intensity over 12 months; secondary: pain-related functioning, frequency of alcohol and drug use over 12 months.

FINDINGS

Primary: randomization to the ImPAT intervention versus SPC predicted significantly lower pain intensity {β [standard error (SE)] = -0.71 (0.29); 95% confidence interval (CI) = -1.29, -0.12}; secondary: relative to the SPC condition, those who received ImPAT also reported improved pain-related functioning [β (SE) = 0.27 (0.11); 95% CI = 0.05, 0.49] and lower frequency of alcohol consumption [β (SE) = -0.77; 95% CI = -1.34, -0.20]. No differences were found between conditions on frequency of drug use over follow-up.

CONCLUSIONS

For adults with pain who are enrolled in addictions treatment, receipt of a psychological pain management intervention (improving pain during addiction treatment) reduced pain and alcohol use and improves pain-related functioning over 12 months relative to a matched-attention control condition.

Telemedicine vs. in-person delivery of intensive short-term dynamic psychotherapy for patients with medically unexplained pain: A 12-month randomized, controlled trial

Introduction This study examined the effectiveness of telemedicine in providing psychotherapy to patients with medically unexplained pain (MUP) who may not have access to in-person treatment. The impact of Internet-delivered intensive short-term dynamic psychotherapy (ID-ISTDP) was investigated for MUP via video teleconferencing (Skype™). Methods A randomized, controlled trial of ISTDP, an evidence-based intervention for MUP, was conducted to compare delivery modalities on variations in MUP symptoms. Eighty-one participants with MUP were randomized to either ID-ISTDP ( n = 39) or in-person ISTDP ( n = 42). Outcome variables included the Numeric Pain Rating Scale, Depression Anxiety Stress Scale-21, Emotion Regulation Questionnaire, Mindful Attention Awareness Scale and the Quality of Life Inventory. In addition, exploratory analyses were used to examine acceptability, satisfaction and compliance in both conditions. Participants were assessed prior to intervention, immediately following the intervention, and 12 months after. Results In the intention-to-treat analysis, in-person ISTDP participants had significantly lower pain intensity than ID-ISTDP participants, both immediately following the intervention ( d = 0.97) and at the 12-month follow-up ( d = 0.82). Moreover, there were significant decreases in depression, anxiety and stress as well as a greater increase in emotion regulation functioning, mindfulness and quality of life observed in the in-person ISTDP group at the end of the intervention and 12 months after the treatment when compared to the ID-ISTDP group. Participants rated both treatment conditions as equally credible and satisfying. Conclusion ISTDP seems most effective when delivered in person in treating MUP patients with highly comorbid conditions with benefits maintained over 12 months.

Chronic Pain and Mental Health Disorders: Shared Neural Mechanisms, Epidemiology, and Treatment

Chronic pain and mental health disorders are common in the general population, and epidemiological studies suggest that a bidirectional relationship exists between these 2 conditions. The observations from functional imaging studies suggest that this bidirectional relationship is due in part to shared neural mechanisms. In addition to depression, anxiety, and substance use disorders, individuals with chronic pain are at risk of other mental health problems including suicide and cigarette smoking and many have sustained sexual violence. Within the broader biopsychosocial model of pain, the fear-avoidance model explains how behavioral factors affect the temporal course of chronic pain and provides the framework for an array of efficacious behavioral interventions including cognitive-behavioral therapy, acceptance-based therapies, and multidisciplinary pain rehabilitation. Concomitant pain and mental health disorders often complicate pharmacological management, but several drug classes, including serotonin-norepinephrine reuptake inhibitors, tricyclic antidepressants, and anticonvulsants, have efficacy for both conditions and should be considered first-line treatment agents.

Fixed-site high-frequency transcutaneous electrical nerve stimulation for treatment of chronic low back and lower extremity pain

Objective

The objective of this study was to determine if fixed-site high-frequency transcutaneous electrical nerve stimulation (FS-TENS) is effective in treating chronic low back and lower extremity pain.

Background

Transcutaneous electrical nerve stimulation is widely used for treatment of chronic pain. General-purpose transcutaneous electrical nerve stimulation devices are designed for stimulation anywhere on the body and often cannot be used while the user is active or sleeping. FS-TENS devices are designed for placement at a pre-determined location, which enables development of a wearable device for use over extended time periods.

Methods

Study participants with chronic low back and/or lower extremity pain self-administered an FS-TENS device for 60 days. Baseline, 30-, and 60-day follow-up data were obtained through an online questionnaire. The primary outcome measure was the patient global impression of change. Pain intensity and interference were assessed using the Brief Pain Inventory. Changes in use of concomitant pain medications were evaluated with a single-item global self-rating.

Results

One hundred and thirty participants were enrolled, with 88 completing the 60-day follow-up questionnaire. Most participants (73.9%) were 50 years of age or older. At baseline, low back pain was identified by 85.3%, lower extremity pain by 71.6%, and upper extremity pain by 62.5%. Participants reported widespread pain, at baseline, with a mean of 3.4 (standard deviation 1.1) pain sites. At the 60-day follow-up, 80.7% of participants reported that their chronic pain had improved and they were classified as responders. Baseline characteristics did not differentiate non-responders from responders. There were numerical trends toward reduced pain interference with walking ability and sleep, and greater pain relief in responders. There was a large difference in use of concomitant pain medications, with 80.3% of responders reporting a reduction compared to 11.8% of non-responders.

Conclusion

FS-TENS is a safe and effective option for treating chronic low back and lower extremity pain. These results motivate the use of FS-TENS in development of wearable analgesic devices.