Functioning In Chronic Pain Patients Research Articles

Prognostic Factors for Physical Functioning After Multidisciplinary Rehabilitation in Patients With Chronic Musculoskeletal Pain: A Systematic Review and Meta-Analysis.

This systematic review aimed to identify and evaluate prognostic factors for long-term (≥6 mo) physical functioning in patients with chronic musculoskeletal pain following multidisciplinary rehabilitation (MDR). Electronic searches conducted in MEDLINE, PsycINFO, EMBASE, CINAHL, Web of Science, and Cochrane CENTRAL revealed 25 original research reports, published 1983-2016, (n=9436). Potential prognostic factors relating to initial pain and physical and psychological functioning were synthesized qualitatively and quantitatively in random effects meta-analyses. The level of evidence (LoE) was evaluated with Grading of Recommendations Assessment, Development and Evaluation (GRADE). Pain-related factors (intensity and chronicity) were not associated with function/disability at long-term follow-up, odds ratio (OR)=0.84; 95% confidence interval (CI), 0.65-1.07 and OR=0.97; 95% CI, 0.93-1.00, respectively (moderate LoE). A better function at follow-up was predicted by Physical factors; higher levels of initial self-reported functioning, OR=1.07; 95% CI, 1.02-1.13 (low LoE), and Psychological factors; low initial levels of emotional distress, OR=0.77; 95% CI, 0.65-0.92, low levels of cognitive and behavioral risk factors, OR=0.85; 95% CI, 0.77-0.93 and high levels of protective cognitive and behavioral factors, OR=1.49; 95% CI, 1.17-1.90 (moderate LoE). While pain intensity and long-term chronicity did not predict physical functioning in chronic pain patients after MDR, poor pretreatment physical and psychological functioning influenced the prognosis negatively. Thus, treatment should further target and optimize these modifiable factors and an increased focus on positive, psychological protective factors may perhaps provide an opening for yet untapped clinical gains.

The Association Between a History of Lifetime Traumatic Events and Pain Severity, Physical Function, and Affective Distress in Patients With Chronic Pain.

This article examines the associations between a history of lifetime abuse and affective distress, fibromyalgianess, pain severity and interference, and physical functioning in chronic pain patients. Our findings support a novel biopsychosocial paradigm in which affective distress and fibromyalgianess interact to play roles in the association between abuse and pain.

Assessing the Construct Validity and Internal Reliability of the Screening Tool Test Your Memory in Patients with Chronic Pain.

Patients with chronic pain often complain about cognitive difficulties, and since these symptoms represent an additional source of suffering and distress, evaluating the cognitive status of these patients with valid and reliable tests should be an important part of their overall assessment. Although cognitive impairment is a critical characteristic of pain, there is no specific measure designed to detect these effects in this population. The objective was to analyze the psychometric properties of the “Test Your Memory” (TYM) test in patients with chronic pain of three different origins. A cross-sectional study was carried out on 72 subjects free of pain and 254 patients suffering from different types of chronic pain: neuropathic pain (104), musculoskeletal pain (99) and fibromyalgia (51). The construct validity of the TYM was assessed using the Mini-Mental State Examination (MMSE), Hospital Anxiety and Depression Scale (HADs), Index-9 from MOS-sleep, SF-12, and through the intensity (Visual Analogical Scale) and duration of pain. An exploratory factor analysis was also performed and internal reliability was assessed using Cronbach’s alpha. After adjusting for potential confounders the TYM could distinguish between pain and pain-free patients, and it was correlated with the: MMSE (0.89, p<0.001); HAD-anxiety (-0.50, p<0.001) and HAD-depression scales (-0.52, p<0.001); MOS-sleep Index-9 (-0.49, p<0.001); and the physical (0.49, p < .001) and mental components (0.55, p < .001) of SF-12. The exploratory structure of the TYM showed an 8-factor solution that explained 53% of the variance, and Cronbach’s alpha was 0.66. The TYM is a valid and reliable screening instrument to assess cognitive function in chronic pain patients that will be of particular value in clinical situations.

Touch Perception Altered by Chronic Pain and by Opioid Blockade.

Touch plays a significant role in human social behavior and social communication, and its rewarding nature has been suggested to involve opioids. Opioid blockade in monkeys leads to increased solicitation and receipt of grooming, suggesting heightened enjoyment of touch. We sought to study the role of endogenous opioids in perception of affective touch in healthy adults and in patients with fibromyalgia, a chronic pain condition shown to involve reduced opioid receptor availability. The pleasantness of touch has been linked to the activation of C-tactile fibers, which respond maximally to slow gentle touch and correlate with ratings of pleasantness. We administered naloxone to patients and healthy controls to directly observe the consequences of µ-opioid blockade on the perceived pleasantness and intensity of touch. We found that at baseline chronic pain patients showed a blunted distinction between slow and fast brushing for both intensity and pleasantness, suggesting reduced C-tactile touch processing. In addition, we found a differential effect of opioid blockade on touch perception in healthy subjects and pain patients. In healthy individuals, opioid blockade showed a trend toward increased ratings of touch pleasantness, while in chronic pain patients it significantly decreased ratings of touch intensity. Further, in healthy individuals, naloxone-induced increase in touch pleasantness was associated with naloxone-induced decreased preference for slow touch, suggesting a possible effect of opioid levels on processing of C-tactile fiber input. These findings suggest a role for endogenous opioids in touch processing, and provide further evidence for altered opioid functioning in chronic pain patients.

Methods and Instruments to Evaluate Cognitive Function in Chronic Pain Patients: A Systematic Review.

We aimed to systematically review the methods and instruments used to evaluate cognitive function in chronic pain (CP) patients. A sensitive search strategy was designed using five databases. Based on the objectives and methodology, we selected cross-sectional studies on adults with chronic non-cancer pain in which cognitive function was assessed using validated instruments. The characteristics of the subjects, control groups, and other variables that might affect cognitive function, and the instruments used, were extracted from each article. In the 42 articles identified, 53 instruments were used to assess cognitive function. Chronic pain criteria were defined in 83.3% of the articles and more than half (57.1%) included single diagnosis samples, with fibromyalgia being the most frequent studied (75%). Patients with prior cognitive impairment were excluded in 61.9% of the studies, and a control group was included in 64.3% of the studies. In most cases potential confounding variables were evaluated. More than 14% of the studies used self-report measures, and 73.8% used neuropsychological instruments, particularly for assessing attention (30%) and memory (27.5%). None of the instruments were specifically validated for pain patients and only five studies analyzed the psychometric properties of the instruments. Various instruments and methods were used to assess cognitive function in CP patients, particularly fibromyalgia patients, but also other cohorts with well-defined CP. The instruments used had been validated, but not for pain populations, thus they require specific adaptation and validation to be used in CP patients. Certain recommendations are made in order to improve the evaluation of cognitive function in these patients.

Somatosensory and affective contributions to emotional, social, and daily functioning in chronic pain patients.

The present study tested the independent and interactive contributions of the somatosensory component of pain (pain intensity) and the affective component of pain (pain unpleasantness) on emotional, social, and daily functioning in chronic pain patients. Participants were 472 patients seeking treatment for chronic orofacial pain. Mean age of the sample was 46.0 years (standard deviation [SD] = 14.67, range 18-78), with 82.2% female. Average pain duration at the time of initial appointment was 75.7 months (SD = 106.66). Participants completed self-report measures of pain intensity, unpleasantness, and functional outcomes at the time of their first appointment. These data were later extracted from participant's de-identified medical records. Multivariate linear regression was used to test the interaction of pain intensity and unpleasantness on outcome measures of emotional, social, and daily functioning. Results revealed that pain intensity contributed to poorer functional outcomes but higher levels of social support even after controlling for pain unpleasantness. After controlling for pain intensity, unpleasantness was associated with higher pain interference and affective distress. There was also pain intensity by unpleasantness interaction on pain interference. Specifically, at lower levels of pain unpleasantness, changes in pain intensity produced greater changes in pain interference than they did at higher levels of pain unpleasantness. Results suggest that both intensity and unpleasantness contribute unique variance to functional outcomes. The results highlight the importance of interventions that not only try to reduce pain levels but also reduce levels of pain unpleasantness.

The effectiveness of “Mindfulness based Cognitive Therapy” on psycho-social performance of chronic low back pain patients (CLBP)

The effectiveness of “Mindfulness based Cognitive Therapy” on psycho-social performance of chronic low back pain patients (CLBP)

Prognostic Factors for Pain Relief and Functional Improvement in Chronic Pain After Inpatient Rehabilitation

To determine the factors associated with pain relief and improved physical functioning in chronic pain patients during outpatient management in the first 5 months immediately after a standardized inpatient pain management program. Prospective cohort study using standardized questionnaires on sociodemographic data, disease outcome, psychosocial factors, change in behavior, and outpatient therapies on discharge from inpatient rehabilitation and during the 5-month follow-up at home (observation period). Stepwise forward multivariate linear regression analysis examined the correlation of these factors with change in pain severity and change in physical functioning. The study included 80.1% female patients, 90.0% had at least 1 comorbidity and 62.9% had chronic pain for≥5 years. On average, pain intensity and depression worsened slightly during the observation period, but the other outcomes remained almost stable. Relief from anxiety (20.7% explained variance) and low baseline depression (5.5%) were the most important predictors for pain relief. Relief from anxiety (13.3%) and low baseline depression (7.1%) were most strongly associated with functional improvement. This study found a strong association of change in pain severity and physical functioning with change in baseline level of affective health and coping during the first outpatient management period after inpatient rehabilitation. As a consequence, it may be possible to improve the treatment of chronic pain by therapy of mood and coping.

The Dilemma of Opioid-Induced Hyperalgesia and Tolerance in Chronic Opioid Therapy = معضلة فرط التألم و حالة التحمل الناتج عن العلاج طويل الأمد بالأدوية ( المسكنات ) الأفيونية

The Dilemma of Opioid-Induced Hyperalgesia and Tolerance in Chronic Opioid Therapy = معضلة فرط التألم و حالة التحمل الناتج عن العلاج طويل الأمد بالأدوية ( المسكنات ) الأفيونية

Opioid Use Patterns and Association with Pain Severity and Mental Health Functioning in Chronic Pain Patients

The objective of this study was to explore the relationship between patterns of opioid use, pain severity, and pain-related mental health in chronic pain patients prescribed opioids. The study was designed as a one-time patient interview with structured pain and opioid use assessments. The study was set in a tertiary care medical center in the United States Department of Veterans Affairs. PATIENTS. Study participants were primary care patients with a pain condition for greater than 6 months who received at least one prescription for an opioid in the prior 12 months. The Prescription Drug Use Questionnaire was used to assess patterns of opioid use. The Pain Outcomes Questionnaire was used to assess pain-related functioning. Symptomatic use of opioid medication (e.g., taking an opioid in response to increased pain) was more common than scheduled (i.e., taking an opioid at regular times) or strategic use of opioid medication (e.g., taking an opioid specifically to engage in activities). Symptomatic use of opioids was associated with poorer pain-related mental health, after controlling for pain duration and pain-related physical functioning. Use of opioids in a scheduled pattern was associated with better pain-related mental health. Patients rarely reported that they used opioids strategically to facilitate functional activities. The patterns in which patients use their opioid medications are associated with their psychological functioning. This is consistent with theory regarding the potential impact of reinforcing effects of opioid medication on functional outcomes. Interventions to encourage strategic or scheduled opioid use warrant investigation as methods to improve pain outcomes with opioids.

Executive function in chronic pain patients and healthy controls: different cortical activation during response inhibition in fibromyalgia. Glass JM, Williams DA, Fernandez-Sanchez ML, et al. J Pain 2011;12(12):1219–29. Epub 2011 Sep 25

Executive function in chronic pain patients and healthy controls: different cortical activation during response inhibition in fibromyalgia. Glass JM, Williams DA, Fernandez-Sanchez ML, et al. J Pain 2011;12(12):1219–29. Epub 2011 Sep 25

Executive Function in Chronic Pain Patients and Healthy Controls: Different Cortical Activation During Response Inhibition in Fibromyalgia

The primary symptom of fibromyalgia (FM) is chronic, widespread pain; however, patients report additional symptoms including decreased concentration and memory. Performance-based deficits are seen mainly in tests of working memory and executive function. Neural correlates of executive function were investigated in 18 FM patients and 14 age-matched healthy controls during a simple Go/No-Go task (response inhibition) while they underwent functional magnetic resonance imaging (fMRI). Performance was not different between FM and healthy control, in either reaction time or accuracy. However, fMRI revealed that FM patients had lower activation in the right premotor cortex, supplementary motor area, midcingulate cortex, putamen and, after controlling for anxiety, in the right insular cortex and right inferior frontal gyrus. A hyperactivation in FM patients was seen in the right inferior temporal gyrus/fusiform gyrus. Despite the same reaction times and accuracy, FM patients show less brain activation in cortical structures in the inhibition network (specifically in areas involved in response selection/motor preparation) and the attention network along with increased activation in brain areas not normally part of the inhibition network. We hypothesize that response inhibition and pain perception may rely on partially overlapping networks, and that in chronic pain patients, resources taken up by pain processing may not be available for executive functioning tasks such as response inhibition. Compensatory cortical plasticity may be required to achieve performance on a par with control groups. Perspective Neural activation (fMRI) during response inhibition was measured in fibromyalgia patients and controls. FM patients show lower activation in the inhibition and attention networks and increased activation in other areas. Inhibition and pain perception may use overlapping networks: resources taken up by pain processing may be unavailable for other processes.

&lt;b&gt;Examination of subjective sensations and vasomotor reaction to environmental temperature changes in &lt;/b&gt;&lt;b&gt;chronic pain patients with impaired cold sensation &lt;/b&gt;

Symptoms of pain in chronic pain patients are known to influence by ambient temperature (AT) change and some of these patients also show temperature unadaptability. These clinical features suggest that alteration of autonomic thermoregulatory systems might be underlying in development and maintenance of chronic pain. In this study, we examined effects of AT change exposure to the pain intensity and autonomic thermoregulatory function in chronic pain patients with impaired cold sensitivity. Two upper extremity neuropathic pain patients who have impaired cold sensitivity in whole body were participated in the present study. The subject sat a chair in an artificial climate chamber (27°C, 50% RH) during the experiment. After the baseline measurements, room temperature was decreased to 15°C in 25 min (cold exposure) and then increased to 40°C in 15 - 20 min (heat exposure). Pain intensity and thermal sensation (cold-cool-warm-hot feeling) during the exposure were frequently measured on a numerical rating scale. Skin temperature, skin blood flow (SBF), and sweating in both hands, and tympanic temperature were also measured continuously throughout the experimental period. In one patient, SBF showed lower baseline value in the affected limb than the healthy limb. During cold exposure, both patients showed increase in their pain intensity in the affected limb, but not expressed any cold feeling in spite of lowering tympanic temperature. Cold exposure decreased SBF in both hands of patients. During heat exposure, both patients expressed hot feeling as an ambient temperature gradually rises, but did not show any change in pain intensity. Heat exposure increased sweating, SBF in both hands of patients. The present study indicated that lowering ambient temperature increased pain intensity in the affected limb of two patients irrespective of impaired cold sensitivity. In these subjects, however, SBF and sweating responded in a different manner to the ambient temperature changes. This could reflect differences in autonomic thermoregulatory function between these patients.

Pain-Related Anxiety as a Mediator of the Effects of Mindfulness on Physical and Psychosocial Functioning in Chronic Pain Patients in Korea

Mindfulness involves reducing potential influences from aversive cognitions, sensations, and emotions on behavior. Mindfulness may influence the experience of pain-related anxiety, and thereby enhance other aspects of physical and psychosocial functioning. Thus, the purpose of this study was to investigate a potential mediating role of pain-related anxiety between mindfulness and physical and psychosocial functioning in chronic pain patients. This cross-sectional/correlational study used archival data (N = 226) obtained from the larger Korean Pain Study at a university-based pain-management center in Korea. Based on the inclusion criterion for the present study, archival data were analyzed for a final sample of 179 patients with chronic pain. Structural equation analyses showed that both the partial- and full-mediation models had adequate goodness-of-fit indices for physical and psychosocial functioning. Subsequent chi-square tests, however, indicated that the more parsimonious full-mediation model was preferred to the partial-mediation model for physical and psychosocial functioning. Bootstrapping procedures yielded significant mediation effects of pain-related anxiety in the full-mediation models on physical and psychosocial functioning. These findings suggest that being mindful may lead indirectly to a decrease in the disabling influences of pain-related anxiety, thereby contributing to better physical and psychosocial functioning, rather than playing a direct contributing role for better functioning among chronic pain patients in Korea. This article examines the mediating role of pain-related anxiety between mindfulness and physical/psychosocial functioning. Results suggest that mindfulness methods may benefit patients having pain-related anxiety and consequent disability. These benefits may derive from the way processes of mindfulness interact with processes of avoidance and with cognitive influences on emotional suffering.

Pain-related anxiety as a mediator of the effects of mindfulness on physical and psychological functioning in chronic pain patients in Korea

Recent correlational studies suggest that processes of mindfulness may improve physical and psychosocial functioning in patient with chronic pain. Here mindfulness includes the ability to be more present-focused and less reactive to some negative psychological experiences. Also, it has been well documented that pain-related anxiety is associated with general functioning in chronic pain patients. However, to our knowledge, possible interactions between mindfulness and pain-related anxiety, in their relations with physical and psychological functioning have not been investigated.

Poderia a atividade física induzir analgesia em pacientes com dor crônica?

A dor crônica caracteriza-se pela persistência do sintoma além do período fisiológico de recuperação do tecido lesado. Essas dores causam incapacidade física e redução da performance cognitiva, reduzem a qualidade de vida e o bem-estar dos pacientes, cujo tratamento proposto contradiz o clássico binômio da terapia da dor aguda (repouso e fármacos). Para a dor crônica prescrevem-se exercícios físicos e sugerem-se tratamentos multidisciplinares. Embora a atividade física seja prescrita há mais de 20 anos, os mecanismos neurofisiológicos envolvidos ainda não são compreendidos. Descrevemos brevemente os mecanismos endógenos de controle da dor crônica e evidências da literatura científica que defendem o sistema opioide como mecanismo de ação na analgesia induzida pelo exercício em indivíduos sadios e atletas. Esse mecanismo também parece agir na população com dor crônica, embora haja controvérsias. Finalizamos o artigo com considerações clínicas para a prescrição do exercício para a população com dor crônica.

(316) Psychological and physiological correlates of a brief intervention to enhance self-regulation in chronic pain

The main objectives of this ongoing study are to determine if training and practice in a brief focused breathing technique is associated with: 1) increased self-regulatory ability to a standard laboratory stressor (cold pressor test) as indexed by Heart Rate Variability; 2) increased pain tolerance to a cold pressor test; 3) decreased breathing rate at follow-up; 4) increased pain management self-efficacy; and 5) decreased self-reported fatigue. Participants were diagnosed with either fibromyalgia (n=13) or masticatory myofascial pain (n=7). Study participants completed an initial laboratory assessment including a diaphragmatic breathing training session. Participants were instructed to practice the technique for three ten-minute sessions each day, and returned to the lab for a second visit after two-weeks. Preliminary results from this study indicate significant improvements in fatigue (p<.01) and pain management self-efficacy (p<.01) between pre and post-training assessments. More striking is the change in pain severity. Mean pain severity scores changed from 4.56 to 3.78 (p<.05) on a 0-10 Visual Analog Scale with 10 being the worst. Tolerance to the cold pressor test increased significantly (60.3s to 76.8s, p<.01). Total power in the HRV spectral frequency range post cold-pressor increased significantly between the two lab sessions (p’s<.05). Additionally, and as expected, breathing rate was significantly reduced at the second assessment. Results of this preliminary study suggest training and practice of a brief diaphragmatic breathing technique is associated with significant changes in a number of areas of physiological and psychological functioning in chronic pain patients. In particular, HRV total power post-training may represent a significant improvement in self-regulatory ability. Further, the significant reduction in pain severity between time one and time two suggests regular use of a self-regulatory training technique may be associated with a reduction in subjective pain measures.

The relationship between resting blood pressure and acute pain sensitivity: effects of chronic pain and alpha-2 adrenergic blockade

This study tested for alpha-2 adrenergic mediation of the inverse relationship between resting blood pressure and acute pain sensitivity in healthy individuals. It also replicated limited prior work suggesting this inverse blood pressure/pain association is altered in chronic pain, and provided the first test of whether chronic pain-related changes in alpha-2 adrenergic function contribute to these alterations. Resting blood pressure was assessed in 32 healthy controls and 24 chronic low back pain participants prior to receiving placebo or an intravenous alpha-2 adrenergic receptor antagonist (yohimbine hydrochloride, 0.4 mg/kg) in a randomized crossover design. Participants experienced three acute pain tasks during both sessions. A significant Systolic Blood Pressure x Participant Type x Drug interaction on finger pressure McGill Pain Questionnaire-Sensory ratings (P < .05) reflected significant hyperalgesic effects of yohimbine in chronic pain participants with lower systolic blood pressures (P < .05) but not those with higher systolic pressures, and no significant effects of yohimbine in controls regardless of blood pressure level. A Drug x Systolic Blood Pressure interaction on finger pressure visual analog scale unpleasantness indicated the inverse blood pressure/pain association was significantly stronger under yohimbine relative to placebo (P < .05). Significant Participant Type x Systolic Blood Pressure interactions (P's < .05) were noted for finger pressure visual analog scale pain intensity and unpleasantness, ischemic pain threshold, and heat pain threshold, reflecting absence or reversal of inverse blood pressure/pain associations in chronic pain participants. Results suggest that blood pressure-related hypoalgesia can occur even when alpha-2 adrenergic systems are blocked. The possibility of upregulated alpha-2 adrenergic inhibitory function in chronic pain patients with lower blood pressure warrants further evaluation.

Acceptance of chronic pain: component analysis and a revised assessment method

Acceptance of chronic pain entails that an individual reduce unsuccessful attempts to avoid or control pain and focus instead on participation in valued activities and the pursuit of personally relevant goals. Recent research suggests that pain-related acceptance leads to enhanced emotional and physical functioning in chronic pain patients above and beyond the influence of depression, pain intensity, and coping. In these studies, acceptance was measured using the Chronic Pain Acceptance Questionnaire (CPAQ). Preliminary analyses of the CPAQ have supported its psychometric properties. The present study sought to further refine the CPAQ by examining its factor structure and evaluating the relations of these factors to other indices of pain-related distress and disability. Although a previously demonstrated factor structure of the CPAQ was generally supported, only factors assessing (a) the degree to which one engaged in life activities regardless of the pain and (b) willingness to experience pain had adequate reliability and validity and were significantly related to the other measures of patient functioning. A revised version of the CPAQ is suggested.

Improvement in the level of psychosocial functioning in chronic pain patients with the use of risperidone.

Psychiatric morbidity is a common complication of chronic pain. Psychopathology may lead to psychosocial dysfunction and poor prognosis for rehabilitation. Emotional factors associated with chronic pain may include depression with anxious and angry affect. Antidepressant medication is a common adjuvant pharmacological treatment in the chronic pain patient. While uncomplicated depression may respond well to antidepressants, some cases are treatment resistant. We present two cases of chronic pain patients with associated depression with angry affect that did not respond to conventional treatment. Addition of the atypical antipsychotic risperidone resulted in symptomatic improvement and higher levels of psychosocial functioning. Atypical antipsychotics may be useful in selected patients with chronic pain and treatment-resistant depression.