Clinical features of chronic pain with neuropathic characteristics: a symptom-based assessment using the pain DETECT questionnaire

Chronic Neuropathic Pain: EEG data in eyes open and eyes closed with painDETECT and Brief Pain Inventory reports

Thirty-six chronic neuropathic pain patients (8 men and 28 women) of Mexican nationality with a mean age of 44±13.98 were recruited for EEG signal recording in eyes open and eyes closed resting state condition. Each condition was recorded for 5 min, with a total recording session time of 10 min. An ID number was given to each patient after signing up for the study, with which they answered the painDETECT questionnaire as a screening process for neuropathic pain alongside their clinical history. The day of the recording, the patients answered the Brief Pain Inventory, as an evaluation questionnaire for the interference of the pain with their daily life. Twenty-two EEG channels positioned in accordance with the 10/20 international system were registered with Smarting mBrain device. EEG signals were sampled at 250 Hz with a bandwidth between 0.1 and 100 Hz. The article provides two types of data: (1) raw EEG data in resting state and (2) the report of patients for two validated pain questionnaires. The data described in this article can be used for classifier algorithms considering stratifying chronic neuropathic pain patients with EEG data alongside their pain scores. In sum, this data is of extreme relevance for the pain field, where researchers have been seeking to integrate the pain experience with objective physiological data, such as the EEG.

Psychological factors can cause false pain classification on painDETECT

Background and aims The painDETECT questionnaire (PD-Q) has been widely used as a screening tool for the identification of neuropathic pain (NeP) as well as a tool for the characterization of patients' pain profile. In contrast to other NeP screening tools, the PD-Q is the only screening tool with weighted sensory descriptors. It is possible that responses to the PD-Q sensory descriptors are influenced by psychological factors, such as catastrophizing or anxiety, which potentially might contribute to an overall higher score of PD-Q and a false positive identification of NeP. This study aimed to explore (i) the relationship between psychological factors (catastrophizing, anxiety, depression and stress) and the total PD-Q score and (ii) if psychological factors are associated with false positive identifications of NeP on the PD-Q compared to clinically diagnosed NeP. Methods The study was a retrospective review of 1,101 patients attending an outpatient pain centre. Patients were asked to complete the PD-Q, the Pain Catastrophizing Scale (PCS), the Depression, Anxiety and Stress Scale (DASS) and the Brief Pain Inventory (BPI). For patients who were identified by PD-Q as having NeP, their medical records were reviewed to establish if they had a clinical diagnosis of NeP. Results Accounting for missing data, complete datasets of 652 patients (mean age 51 (SD14) years, range 18-88; 57% females) were available for analysis. Based on PD-Q scoring, NeP was likely present in 285 (44%) patients. Depression, anxiety, stress, catastrophizing, BPI pain and BPI interference were all significantly related to each other (p < 0.0001) and patients displaying these traits were significantly more likely to have a positive PD-Q score (p < 0.0001). For patients classified by PD-Q as having NeP, only 50% of patients had a clinical diagnosis of NeP. Anxiety was significantly associated with a false positive classification of NeP on PD-Q (p = 0.0036). Conclusions Our retrospective study showed that psychological factors including catastrophizing, depression, anxiety, and stress were all influential in producing a higher score on the PD-Q. We observed a high rate of false positive NeP classification which was associated with the presence of anxiety. Implications Clinicians and researchers should be aware that a patient's psychological state may influence the responses to PD-Q and consequently the final PD-Q score and its NeP classification.

Predicting factors of outcome in multidisciplinary treatment of chronic neuropathic pain

Purpose

Evidence of the effectiveness of multidisciplinary treatment with a focus on neuropathic pain is still rare. The present study investigated whether multidisciplinary treatment leads to improvement of neuropathic pain in outcome (pain intensity and disability) and psychological (depression, pain acceptance, and catastrophizing) variables at posttreatment and 3-month follow-up. We examined whether and to what extent psychological changes can predict long-term outcome at 3-month follow-up, when other variables are controlled for (baseline characteristics and changes in pain parameters).

Patients and methods

Patients suffering from a chronic neuropathic pain condition (n=141) attended an inpatient multidisciplinary program lasting about 15 continuous days with self-report data collected at pretreatment, posttreatment, and 3-month follow-up.

Results

Repeated-measures ANOVAs showed a significant improvement of pain intensity, disability, pain acceptance, catastrophizing, and depression at posttreatment. These improvements remained stable over the 3-month follow-up for all variables except for depression. The inclusion of psychological changes in multiple regression analyses greatly increased the variance in outcome, explained by baseline characteristics and changes in pain parameters.

Conclusion

The results could help clinicians to determine which variables should be emphasized during inpatient treatment and during the follow-up period, in order to maintain the gains after an inpatient multidisciplinary treatment for neuropathic pain.

Perspective

The present study demonstrates the beneficial effects of an inpatient multidisciplinary program for neuropathic pain and further question the resistant nature of neuropathic pain to treatment. The results add evidence to the relevance of cognitive-behavioral models of pain positing an important role for pain-related thoughts and emotions in long-term outcome following multidisciplinary pain treatment.

Protocol of the randomised placebo controlled pilot trial of the management of acute sciatica (SCIATICA): a feasibility study

INTRODUCTION

Acute sciatica (symptom duration less than 4 weeks), a major cause of pain and disability, is a common presentation to medical practices and hospital emergency departments. Selective CT fluoroscopy transforaminal epidural steroid injection is often used with the hope of reducing pain and improving function. Recently, there has been interest in using systemic corticosteroids in acute sciatica. However, there is limited evidence to inform management of selective CT fluoroscopy transforaminal epidural steroid in subacute and chronic sciatica and there is no evidence in acute sciatica, even though the practice is widespread. There is also limited evidence for the use of systemic corticosteroids in acute sciatica. Furthermore, the management of selective CT fluoroscopy transforaminal epidural steroid versus systemic steroids has never been directly studied.

METHODS AND ANALYSIS

SCIATICA is a pilot/feasibility study of patients with acute sciatica designed to evaluate the feasibility of undertaking a blinded four-arm randomised controlled intervention study of (1) selective CT fluoroscopy transforaminal epidural steroid (arm 1), (2) selective CT fluoroscopy transforaminal epidural saline (arm 2), (3) 15 days tapering dose of oral steroids (arm 3) and (4) a sham epidural and oral placebo control (arm 4). This feasibility study is designed to evaluate head-to-head, route versus pharmacology of interventions. The primary outcome measure is the Oswestry Disability Index (ODI) at 3 weeks. Secondary outcome is the ODI at 48 weeks. Other outcomes include numerical rating scale for leg pain, Pain DETECT Questionnaire, quality of life, medication use, rescue procedures or surgery, and adverse events. Results of outcomes from this randomised controlled trial will be used to determine the feasibility, sample size and power calculations for a large multicentre study.

ETHICS AND DISSEMINATION

The study has been approved by South Eastern Sydney Local Health District Human Research Ethics Committee (HREC/15/331/POHW/586).

TRIAL REGISTRATION NUMBER

NCT03240783; Pre-results.

Identification of pain categories associated with change in pain in patients receiving placebo: data from two phase 3 randomized clinical trials in symptomatic knee osteoarthritis

Background

Pain is the principal clinical symptom of osteoarthritis (OA), and development of safe and effective analgesics for OA pain is needed. Drug development of new analgesics for OA pain is impaired by substantial change in pain in patients receiving placebo, and more data describing clinical characteristics and pain categories particularly associated with this phenomenon is needed.

The purpose of this post-hoc analysis was to investigate clinical characteristics and pain categories and their association with radiographic progression and placebo pain reduction (PPR) in OA patients as measured the Western Ontario and McMasters Arthritis (WOMAC).

Methods

Pooled data from the placebo groups of two phase III randomized clinical trials in patients with knee OA followed for 2 years were analyzed. Differences between individual sub-scores and pain categories of weight-bearing and non-weight bearing pain over time were assessed. Selected patient baseline characteristics were assessed for association with PPR. Association between pain categories and radiographic progression was analyzed.

Results

The reduction of pain in placebo-treated patients was significantly higher in the composite of questions related to weight-bearing pain compared to non-weight-bearing pain of the target knee. Baseline BMI, age and JSW were not associated with pain change. Pain reduction was higher in the Target knee, compared to the Non-Target knee at all corresponding time-points. A very weak correlation was found between weight-bearing pain and progression in the non-target knee.

Conclusions

These results indicate that the reduction in pain in patients treated with placebo is significantly different between pain categories, as weight-bearing pain was significantly more reduced compared to non-weight-bearing pain. Further research in pain categories in OA is warranted.

Trial Registration

NCT00486434 (trial 1) and NCT00704847 (trial 2)

A Review of the Emotional Aspects of Neuropathic Pain: From Comorbidity to Co-Pathogenesis

Neuropathic pain is characterized by both sensory and affective disturbances, supporting the notion that pain and mood disorders share common pathogenetic mechanisms. Moreover, biological and neuroimaging data show that common brain areas are involved in the modulation of painful and emotional experiences. Improved understanding of the molecular mechanisms underlying the role of neuroinflammation in regulation of affective behavior in neuropathic pain states is important for the development of novel therapeutic strategies. Psychological issues must be considered a factor influencing treatment and outcome in patients with neuropathic pain.

Funding: Pfizer, Italy.

Pain experiences of patients with musculoskeletal pain + central sensitization: A comparative Group Delphi Study

Objectives

Central sensitization (CS) is regarded as an important contributing factor for chronification of musculoskeletal pain (MSP). It is crucial to identify CS, as targeted multimodal treatment may be indicated. The primary objective of this study was therefore to explore pain experience of individuals with MSP+CS in order to gain a better understanding of symptoms in relation to CS from a patient perspective. The secondary objective was to investigate whether pain experiences of patients with MSP+CS differ from those of individuals with neuropathic pain (NP).

Methods

We conducted a comparative Group Delphi Study including patients with MSP+CS and neuropathic pain (NP). 13 guiding questions were used to gather information about sensory discriminatory, affective and associated bodily, mental and emotional phenomena related to the pain experience of patients. Descriptions were categorized using qualitative content analysis. Additionally, patients completed several pain related questionnaires.

Results

Nine participants with MSP+CS and nine participants with NP participated. The Delphi procedure revealed three main themes: psycho-emotional factors, bodily factors and environmental factors. Descriptions of patients with MSP+CS showed a complex picture, psycho-emotional factors seem to have a considerable impact on pain provocation, aggravation and relief. Impairments associated with mental ability and psyche affected many aspects of daily life. In contrast, descriptions of patients with NP revealed a rather mechanistic and bodily oriented pain experience.

Discussion

Patients with MSP+CS reported distinct features in relation to their pain that were not captured with current questionnaires. Insight in patient’s pain experience may help to choose and develop appropriate diagnostic instruments.

Brain morphological alternation in chronic pain patients with neuropathic characteristics

Background

Neuropathic characteristics are highly involved in the development of chronic pain both physically and psychologically. However, little is known about the relationship between neuropathic characteristics and brain morphological alteration.

Objectives

The aim of this study is to investigate the mechanisms of chronic pain development by examining the above-mentioned relationships by voxel-based morphometry in patients with chronic pain.

Methods

First, we assessed neuropathic characteristics using the painDETECT Questionnaire in 12 chronic pain patients. Second, to assess the gray matter volume changes by voxel-based morphometry, we conducted magnetic resonance imaging of the brain. We applied multiregression analysis of these two assessment methods.

Results

There were significant positive correlations between painDETECT Questionnaire scores and the gray matter volume in the bilateral anterior cingulate cortex and right posterior cingulate cortex.

Conclusions

Our findings suggest that neuropathic characteristics strongly affect the brain regions related to modulation of pain in patients with chronic pain and, therefore, contribute to the severity of chronic pain.

Psychological Considerations in the Assessment and Treatment of Pain in Neurorehabilitation and Psychological Factors Predictive of Therapeutic Response: Evidence and Recommendations from the Italian Consensus Conference on Pain in Neurorehabilitation

Background: In order to provide effective care to patients suffering from chronic pain secondary to neurological diseases, health professionals must appraise the role of the psychosocial factors in the genesis and maintenance of this condition whilst considering how emotions and cognitions influence the course of treatment. Furthermore, it is important not only to recognize the psychological reactions to pain that are common to the various conditions, but also to evaluate how these syndromes differ with regards to the psychological factors that may be involved. As an extensive evaluation of these factors is still lacking, the Italian Consensus Conference on Pain in Neurorehabilitation (ICCPN) aimed to collate the evidence available across these topics.

Objectives: To determine the psychological factors which are associated with or predictive of pain secondary to neurological conditions and to assess the influence of these aspects on the outcome of neurorehabilitation.

Methods: Two reviews were performed. In the first, a PUBMED search of the studies assessing the association between psychological factors and pain or the predictive value of these aspects with respect to chronic pain was conducted. The included papers were then rated with regards to their methodological quality and recommendations were made accordingly. In the second study, the same methodology was used to collect the available evidence on the predictive role of psychological factors on the therapeutic response to pain treatments in the setting of neurorehabilitation.

Results: The first literature search identified 1170 results and the final database included 189 articles. Factors such as depression, anxiety, pain catastrophizing, coping strategies, and cognitive functions were found to be associated with pain across the various conditions. However, there are differences between chronic musculoskeletal pain, migraine, neuropathy, and conditions associated with complex disability with regards to the psychological aspects that are involved. The second PUBMED search yielded 252 studies, which were all evaluated. Anxiety, depression, pain catastrophizing, coping strategies, and pain beliefs were found to be associated to different degrees with the outcomes of multidisciplinary programs, surgery, physical therapies, and psychological interventions. Finally, sense of presence was found to be related to the effectiveness of virtual reality as a distraction tool.

Conclusions: Several psychological factors are associated with pain secondary to neurological conditions and should be acknowledged and addressed in order to effectively treat this condition. These factors also predict the therapeutic response to the neurorehabilitative interventions.