Cognitive performance is related to central sensitization and health-related quality of life in patients with chronic whiplash-associated disorders and fibromyalgia

Background: A growing body of research has demonstrated that impaired central pain modulation or central sensitization (CS) is a crucial mechanism for the development of persistent pain in chronic whiplash-associated disorders (WAD) and fibromyalgia (FM) patients. Furthermore, there is increasing evidence for cognitive dysfunctions among these patients. In addition, chronic WAD and FM patients often report problems with health-related quality of life (QoL). Yet, there is limited research concerning the interrelations between cognitive performance, indices of CS, and health-related QoL in these patients. Objectives: (1) Examining the presence of cognitive impairment, CS, and limitations on health-related QoL in patients with chronic WAD and FM compared to healthy controls. (2) Examining interrelations between performance-based cognitive functioning, CS, and self-reported health-related QoL in these 3 study groups. Study Design: A case-control study was conducted. Setting: The present study took place at the University Hospital Brussels, the University of Brussels, and the University of Antwerp. Methods: Fifty-nine patients (16 chronic WAD patients, 21 FM patients, and 22 pain-free volunteers) filled out the Short Form 36 item Health Survey (SF-36), a self-reported psychosocial questionnaire, to assess health-related QoL. Next, they were subjected to various pain measurements (pressure hyperalgesia, deep-tissue hyperalgesia, temporal summation [TS], and conditioned pain modulation [CPM]). Finally, participants completed a battery of performance-based cognitive tests (Stroop task, psychomotor vigilance task [PVT], and operation span task [OSPAN]). Results: Significant cognitive impairment, bottom-up sensitization, and decreased health-related QoL were demonstrated in patients with chronic WAD and FM compared to healthy controls (P < 0.017). CPM was comparable between the 3 groups. Cognitive performance was significantly related to central pain modulation (deep-tissue hyperalgesia, TS, CPM) as well as to self-reported health-related QoL (P < 0.05). Decreased cognitive performance was related to deficient central pain modulation in healthy controls. Further, significant correlations between decreased cognitive performance and reduced health-related QoL were revealed among all study groups. Additionally, FM patients showed correlations between cognitive impairment and increased health-related QoL. Remarkably, impaired selective attention and working memory were related to less TS, whereas impaired sustained attention was correlated with dysfunctional CPM in FM patients. Limitations: Based on the current cross-sectional study no firm conclusions can be drawn on the causality of the relations. Conclusion: In conclusion, this paper has demonstrated significant cognitive deficits, signs of CS, and reduced health-related QoL in chronic WAD and FM patients compared to healthy individuals. Significant relations between cognitive performance and CS as well as health-related QoL were demonstrated. These results provide preliminary evidence for the clinical importance of objectively measured cognitive deficits in patients with chronic WAD and FM

The efficacy of patient education in whiplash associated disorders : a systematic review

Background: Until now, there is no firm evidence for conservative therapy in patients with chronic Whiplash Associated Disorders (WAD). While chronic WAD is a biopsychosocial problem, education may be an essential part in the treatment and the prevention of chronic WAD. However, it is still unclear which type of educative intervention has already been used in WAD patients and how effective such interventions are. Objective: This systematic literature study aimed at providing an overview of the literature regarding the currently existing educative treatments for patients with whiplash or WAD and their evidence. Study Design: Systematic review of the literature Methods: A systematic literature search was conducted in the following databases: Pubmed, Springerlink, and Web of Science using different keyword combinations. We included randomized controlled clinical trials (RCT) that encompass the effectiveness of education for patients with WAD. The included articles were evaluated on their methodological quality. Results: Ten RCT's of moderate to good quality remained after screening. Both oral and written advice, education integrated in exercise programs and behavioral programs appear effective interventions for reducing pain and disability and enhancing recovery and mobility in patients with WAD. In acute WAD, a simple oral education session will suffice. In subacute or chronic patients broader (multidisciplinary) programs including education which tend to modulate pain behavior and activate patients seems necessary. Limitations: Because of limited studies and the broad range of different formats and contents of education and different outcome measures, further research is needed before solid conclusions can be drawn regarding the use and the modalities of these educational interventions in clinical practice. Conclusion: Based on this systematic literature study is seems appropriate for the pain physician to provide education as part of a biopsychosocial approach of patients with whiplash. Such education should target removing therapy barriers, enhancing therapy compliance and preventing and treating chronicity. Still, more studies are required to provide firm evidence for the type, duration, format, and efficacy of education in the different types of whiplash patients

Best evidence rehabilitation for chronic pain, part 3 : low back pain

Chronic Low Back Pain (CLBP) is a major and highly prevalent health problem. Given the high number of papers available, clinicians might be overwhelmed by the evidence on CLBP management. Taking into account the scale and costs of CLBP, it is imperative that healthcare professionals have access to up-to-date, evidence-based information to assist them in treatment decision-making. Therefore, this paper provides a state-of-the-art overview of the best evidence non-invasive rehabilitation for CLBP. Taking together up-to-date evidence from systematic reviews, meta-analysis and available treatment guidelines, most physically inactive therapies should not be considered for CLBP management, except for pain neuroscience education and spinal manipulative therapy if combined with exercise therapy, with or without psychological therapy. Regarding active therapy, back schools, sensory discrimination training, proprioceptive exercises, and sling exercises should not be considered due to low-quality and/or conflicting evidence. Exercise interventions on the other hand are recommended, but while all exercise modalities appear effective compared to minimal/passive/conservative/no intervention, there is no evidence that some specific types of exercises are superior to others. Therefore, we recommend choosing exercises in line with the patient's preferences and abilities. When exercise interventions are combined with a psychological component, effects are better and maintain longer over time

Associations between cognitive performance and pain in chronic fatigue syndrome : comorbidity with fibromyalgia does matter

Background: In addition to the frequently reported pain complaints, performance-based cognitive capabilities in patients with chronic fatigue syndrome (CFS) with and without comorbid fibromyalgia (FM) are significantly worse than those of healthy controls. In various chronic pain populations, cognitive impairments are known to be related to pain severity. However, to the best of our knowledge, the association between cognitive performance and experimental pain measurements has never been examined in CFS patients. Objectives: This study aimed to examine the association between cognitive performance and self-reported as well as experimental pain measurements in CFS patients with and without FM. Study Design: Observational study. Setting: The present study took place at the Vrije Universiteit Brussel and the University of Antwerp. Methods: Forty-eight (18 CFS-only and 30 CFS+FM) patients and 30 healthy controls were studied. Participants first completed 3 performance-based cognitive tests designed to assess selective and sustained attention, cognitive inhibition, and working memory capacity. Seven days later, experimental pain measurements (pressure pain thresholds [PPT], temporal summation [TS], and conditioned pain modulation [CPM]) took place and participants were asked to fill out 3 questionnaires to assess self-reported pain, fatigue, and depressive symptoms. Results: In the CFS+FM group, the capacity of pain inhibition was significantly associated with cognitive inhibition. Self-reported pain was significantly associated with simple reaction time in CFS-only patients. The CFS+FM but not the CFS-only group showed a significantly lower PPT and enhanced TS compared with controls. Limitations: The cross-sectional nature of this study does not allow for inferences of causation. Conclusions: The results underline disease heterogeneity in CFS by indicating that a measure of endogenous pain inhibition might be a significant predictor of cognitive functioning in CFS patients with FM, while self-reported pain appears more appropriate to predict cognitive functioning in CFS patients without FM

Does acetaminophen activate endogenous pain inhibition in chronic fatigue syndrome/fibromyalgia and rheumatoid arthritis? : a double-blind randomized controlled cross-over trial

Background: Although enhanced temporal summation (TS) and conditioned pain modulation (CPM), as characteristic for central sensitization, has been proved to be impaired in different chronic pain populations, the exact nature is still unknown. Objectives: We examined differences in TS and CPM in 2 chronic pain populations, patients with both chronic fatigue syndrome (CFS) and comorbid fibromyalgia (FM) and patients with rheumatoid arthritis (RA), and in sedentary, healthy controls, and evaluated whether activation of serotonergic descending pathways by acetaminophen improves central pain processing. Study Design: Double-blind randomized controlled trial with cross-over design. Methods: Fifty-three women (19 CFS/FM patients, 16 RA patients, and 18 healthy women) were randomly allocated to the experimental group (1 g acetaminophen) or the placebo group (1 g dextrose). Participants underwent an assessment of endogenous pain inhibition, consisting of an evaluation of temporal summation with and without conditioned pain modulation (CPM). Seven days later groups were crossed-over. Patients and assessors were blinded for the allocation. Results: After intake of acetaminophen, pain thresholds increased slightly in CFS/FM patients, and decreased in the RA and the control group. Temporal summation was reduced in the 3 groups and CPM at the shoulder was better overall, however only statistically significant for the RA group. Healthy controls showed improved CPM for both finger and shoulder after acetaminophen, although not significant. Limitations: The influence of acetaminophen on pain processing is inconsistent, especially in the patient groups examined. Conclusion: This is the first study comparing the influence of acetaminophen on central pain processing in healthy controls and patients with CFS/FM and RA. It seems that CFS/ FM patients present more central pain processing abnormalities than RA patients, and that acetaminophen may have a limited positive effect on central pain inhibition, but other contributors have to be identified and evaluated

Hyperexcitability of the central nervous system in children with chronic pain : a systematic review

OBJECTIVE: Hyperexcitability of the central nervous system plays an important role in the development and maintenance of chronic pain in adults. This knowledge has led to improved treatment strategies within this population. In children, however, research on the presence of central hyperexcitability is scarce. To further investigate this topic in children with chronic pain, there is a need for a clear literature overview. DESIGN: Systematic review. METHODS: The literature search was performed using the electronic databases PubMed and Web of Science. An article was considered eligible if it included children (age two to 12 years) diagnosed with chronic pain. Articles had to report original research outcomes related to central hyperexcitability, and a comparison with a healthy control group was necessary. Characteristics of the study sample, the assessment, and conclusions regarding central hyperexcitability were extracted from each included article. RESULTS: Twelve case-control studies were included with moderate to good methodological quality (510 children with chronic pain and 670 healthy controls). After summarizing the articles' results on indices of central hyperexcitability, we concluded that secondary hyperalgesia might be present in children with recurrent abdominal pain, juvenile fibromyalgia, and juvenile idiopathic arthritis. Preliminary evidence exists for altered cortical nociceptive processing in children with migraine and recurrent abdominal pain. CONCLUSIONS: Based on the results of this review, central hyperexcitability might be present in in several pediatric chronic pain conditions. Further research on other manifestations of central hyperexcitability (e.g., bottom-up and top-down mechanisms and nociceptive brain changes) is necessary to provide firm evidence about its presence in children with chronic pain

Treatment of pain following cancer : applying neuro-immunology in rehabilitation practice

Aim: Pain is the second most frequent persistent symptom following cancer treatment. This article aims at explaining how the implementation of contemporary pain neuroscience can benefit rehabilitation for adults following cancer treatment within an evidence-based perspective. Materials and methods: Narrative review. Results: First, pain education is an effective but underused strategy for treating cancer related pain. Second, our neuro-immunological understanding of how stress can influence pain highlights the importance of integrating stress management into the rehabilitation approach for patients having cancer-related pain. The latter is supported by studies that have examined the effectiveness of various stress management programmes in this population. Third, poor sleep is common and linked to pain in patients following cancer treatment. Sleep deprivation results in a low-grade inflammatory response and consequent increased sensitivity to pain. Cognitive behavioural therapy for sleep difficulties, stress management and exercise therapy improves sleep in patients following cancer treatment. Finally, exercise therapy is effective for decreasing pain in patients following cancer treatment, and may even decrease pain-related side effects of hormone treatments commonly used in cancer survivors. Conclusions: Neuro-immunology has increased our understanding of pain and can benefit conservative pain treatment for adults following cancer treatment

Unravelling Impaired Hypoalgesia at Rest and in Response to Exercise in Patients with Chronic Whiplash-Associated Disorders:Effects of a Single Administration of Selective Serotonin Reuptake Inhibitor versus Selective Norepinephrine Reuptake Inhibitor

(1) Background: Noradrenaline and serotonin have modulatory roles in pain signaling and in exercise-induced hypoalgesia. Patients with chronic whiplash-associated disorders often show impaired exercise-induced hypoalgesia. Therefore, this study aimed to examine the isolated effect of activating serotonergic or noradrenergic descending pathways on hypoalgesia at rest and in response to exercise in patients with chronic WAD by using respectively a single dose of a selective serotonin reuptake inhibitor (SSRI) and a selective norepinephrine reuptake inhibitor (NRI). (2) Methods: Twenty-five people with chronic WAD participated in this double-blind randomized controlled crossover experiment. Serotonin and noradrenaline concentrations were modulated by the oral ingestion of a single dose of citalopram (i.e., SSRI) or atomoxetine (i.e., SNRI). Quantitative sensory testing (including pressure pain thresholds and conditioned pain modulation) was measured before and after exercise in combination with no medication (1), atomoxetine (2), or citalopram (3) at three different test days. (3) Results: Random-intercept linear mixed models analysis was used to analyze pain outcomes (i.e., pain at rest and exercise-induced hypoalgesia) before and after exercise over the three conditions in patients with chronic WAD. No differences in pain at rest were found between the three conditions before exercise. The effect of exercise on pain outcome measures was not influenced by medication intake. The occupational status of the participants had a significant influence on the effect of exercise and medication on pain outcomes (p &lt; 0.05). Patients working full-time had some positive effect of atomoxetine on pain facilitation (p &lt; 0.05). Unemployed patients had some negative effect of citalopram on pain tolerance and experienced exercise-induced hypoalgesia (p &lt; 0.05). (4) Conclusions: A single dose of citalopram or atomoxetine did not result in changes in hypoalgesia at rest and in response to exercise. These results do not support the use of SSRI or selective NRI to overcome impaired hypoalgesia at rest or in response to exercise in people with chronic WAD. Effect of exercise and medication on pain in patients with chronic WAD is influenced by the occupational status.</p