Psychological flexibility and traditional pain management strategies in relation to patient functioning with chronic pain: an examination of a revised instrument.

Recent developments in cognitive behavioral theory emphasize the role of "psychological flexibility" in adaptive functioning. Psychological flexibility includes processes of acceptance, mindfulness, values, and cognitive defusion. The present study was intended to investigate aspects of psychological flexibility in relation to the functioning of patients with chronic pain. Two hundred sixty patients seeking treatment for chronic pain completed a battery of measures, including an expanded version of an instrument assessing responses to pain that reflect both psychological flexibility and traditionally conceived "pain management strategies" (ie, pacing, relaxation, positive self-statements). Initial psychometric evaluation of the expanded instrument yielded 2 reliable subscales, as hypothesized. Both subscales were correlated with measures of emotional functioning and psychosocial disability, although psychological flexibility achieved larger correlations and was correlated with additional measures of physical functioning, health care use, and work status. Regression analyses indicated that, after pain and patient background variables were statistically controlled, psychological flexibility accounted for significant variance in eight separate measures of functioning while pain management strategies accounted for significant variance in none. These results may call for a shift in our approaches to chronic pain in line with developments taking place in broader areas of behavioral and cognitive therapy. PERSPECTIVE: This study includes development of an instrument for assessing coping, consisting of traditionally conceived coping strategies and a process that may be unfamiliar to most readers, termed "psychological flexibility." Results demonstrated that this process, a blend of acceptance, values-based action, mindfulness, and cognitive defusion, is significantly related to patient functioning with chronic pain.     

Acceptance,Mindfulness, and Values-Based Action May Counteract Fear and Avoidance of Emotions in Chronic Pain: An Analysis of Anxiety Sensitivity

People often respond with distress and avoidance to their own negative experiences, such as the physical, cognitive, and emotional aspects of depression or anxiety. When people with chronic pain respond this way, their overall level of distress may increase, they may struggle to avoid their emotional experiences, and their daily functioning may decrease. The purpose of this study was to examine the role of anxiety sensitivity (AS), or “fear of anxiety,” in relation to these processes. It was predicted that those persons with chronic pain who report higher AS will also report higher emotional distress and greater disability caused by chronic pain. A second purpose was to examine whether therapeutic processes designed to reduce emotional avoidance, namely, acceptance, mindfulness, and values, could be demonstrated to reduce the role of AS in relation to this distress and disability based on a statistical model including these variables. Subjects were 125 consecutive adult patients (64.8% women) seeking services from a specialty pain service in the United Kingdom. All patients completed a standard set of measures of AS, acceptance of pain, mindfulness, and values-based action, as well as measures of pain, disability, and emotional functioning, at their initial consultation, and these data formed the basis for the current study. In correlation and regression analyses, AS was associated with greater pain, disability, and distress. In regression analyses, the 3 proposed therapeutic processes reduced the average variance accounted for by AS in patient functioning from ΔR² = .21 to ΔR² = .048. This means that when the 3 therapeutic variables are taken into account statistically, AS alone retained relatively little association with patient functioning. These results suggest that AS may amplify the impact of emotional distress on patient functioning in chronic pain and that processes of acceptance, mindfulness, and values-based action may reduce this effect.PerspectiveHumans can fear and struggle to avoid their own emotional experiences, even when these cannot harm them. Data presented here show individuals with chronic pain have more distress and disability when they manifest more fear of anxiety symptoms, and behavior patterns of “acceptance” and “mindfulness” may reduce this effect.     

The role of mindfulness in a contextual cognitive-behavioral analysis of chronic pain-related suffering and disability

An increasing number of studies consider the specific processes by which distressing sensations, thoughts, and emotional experiences exert their influence on the daily functioning of those who suffer with chronic pain. Clinical methods of mindfulness and the processes that underlie them appear to have clear implications in this area, but have not been systematically investigated to this point in time. The purpose of the present study was to examine mindfulness in relation to the pain, emotional, physical, and social functioning of individuals with chronic pain. The present study included 105 consecutive patients attending a clinical assessment for treatment of chronic pain. Each completed a standardized battery of questionnaires, including a measure of mindfulness, the Mindful Attention Awareness Scale [Brown KW, Ryan RM. The benefits of being present: mindfulness and its role in psychological well-being. J Pers Soc Psychol 2003;84:822-48]. Correlation analyses indicated that mindfulness was unrelated to age, gender, education, or chronicity of pain, but was significantly related to multiple measures of patient functioning. In multiple regression analyses, after controlling for patient background variables, pain intensity, and pain-related acceptance, mindfulness accounted for significant variance in measures of depression, pain-related anxiety; physical, psychosocial, and "other" disability. In each instance greater mindfulness was associated with better functioning. The combined increments of variance explained from acceptance of pain and mindfulness were at least moderate and, in some cases, appeared potentially meaningful. The behavioral processes of mindfulness and their accessibility to scientific study are considered.     

General psychological acceptance and chronic pain: There is more to accept than the pain itself

An increasing body of research demonstrates that acceptance of pain is significantly associated with the quality of daily functioning in people with chronic pain. The aim of the present study was to examine acceptance more broadly in relation to a wider range of undesirable experiences these people may encounter, such as other physical symptoms, experiences of emotional distress, or distressing thoughts. One hundred forty‐four, consecutive, adult patients attending interdisciplinary treatment for chronic pain participated in this study. They completed the Acceptance and Action Questionnaire‐II (AAQ‐II [Bond F, Hayes SC, Baer RA, Carpenter KM, Orcutt HK, Waltz T, Zettle RD. Preliminary psychometric properties of the Acceptance Action Questionnaire‐II: a revised measure of psychological flexibility and acceptance, submitted for publication]), measuring their general psychological acceptance. They also completed measures of emotional, physical, and psychosocial functioning, pain acceptance, and mindfulness. The AAQ‐II achieved satisfactory internal consistency, α = .89, and factor analysis revealed a unitary factor structure. Primary results showed that general psychological acceptance significantly correlated with depression, r = −.69, pain‐related anxiety, r = −.59, physical disability, r = −.42, and psychosocial disability, r = −.65, all p < .001. Hierarchical regression analyses showed that general psychological acceptance added a significant increment of explained variance to the prediction of patient functioning, independent of patient background characteristics, pain, acceptance of pain, and mindfulness. These results suggest that, when people with chronic pain are willing to have undesirable psychological experiences without attempting to control them, they may function better and suffer less. General acceptance may have a unique role to play in the disability and suffering of chronic pain beyond similar processes such as acceptance of pain or mindfulness.     

Profiles of Pain Acceptance and Values-Based Action in the Assessment and Treatment of Chronic Pain

Pain acceptance and values-based action are relevant to treatment outcomes in those with chronic pain. It is unclear if patterns of responding in these 2 behavioral processes can be used to classify patients into distinct classes at treatment onset and used to predict treatment response. This observational cohort study had 2 distinct goals. First, it sought to classify patients at assessment based on pain acceptance and values-based action (N = 1746). Second, it sought to examine treatment outcomes based on class membership in a sub-set of patients completing an interdisciplinary pain rehabilitation program of Acceptance and Commitment Therapy for chronic pain (N = 343). Latent profile analysis was used in the larger sample to identify 3 distinct patient classes: low acceptance and values-based (AV) action (Low AV; n = 424), moderate acceptance and values-based action (Moderate AV; n = 983) and high acceptance and values-based action (High AV; n = 339). In the smaller treated sample, participants in the Low AV and Moderate AV class demonstrated improvements across all outcome variables, whereas those in the High AV class did not. These findings support the role of pain acceptance and values-based action in those with chronic pain.PerspectiveIndividuals with chronic pain can be classified with respect to pain acceptance and values-based action and these groups may respond differently to treatment.     

Low mindfulness predicts pain catastrophizing in a fear-avoidance model of chronic pain

The relationship between persistent pain and self-directed, non-reactive awareness of present-moment experience (i.e., mindfulness) was explored in one of the dominant psychological theories of chronic pain – the fear-avoidance model [53]. A heterogeneous sample of 104 chronic pain outpatients at a multidisciplinary pain clinic in Australia completed psychometrically sound self-report measures of major variables in this model: Pain intensity, negative affect, pain catastrophizing, pain-related fear, pain hypervigilance, and functional disability. Two measures of mindfulness were also used, the Mindful Attention Awareness Scale [4] and the Five-Factor Mindfulness Questionnaire [1]. Results showed that mindfulness significantly negatively predicts each of these variables, accounting for 17–41% of their variance. Hierarchical multiple regression analysis showed that mindfulness uniquely predicts pain catastrophizing when other variables are controlled, and moderates the relationship between pain intensity and pain catastrophizing. This is the first clear evidence substantiating the strong link between mindfulness and pain catastrophizing, and suggests mindfulness might be added to the fear-avoidance model. Implications for the clinical use of mindfulness in screening and intervention are discussed.     

Efficacy of Online-Based Acceptance and Commitment Therapy for Chronic Pain: A Systematic Review and Meta-Analysis

Acceptance and Commitment Therapy (ACT) has been widely tested for chronic pain, with demonstrated efficacy. Nevertheless, although there is meta-analytical evidence on the efficacy of face-to-face ACT, no reviews have been performed on online ACT in this population. The aim of this meta-analysis is to determine the efficacy of online ACT for adults with chronic pain, when compared with controls. PubMed, PsycINFO, CENTRAL, and Web of Knowledge were searched for randomized controlled trials (RCTs) of online-delivered ACT for chronic pain. Effects were analyzed at post-treatment and follow-up, by calculating standardized mean differences. Online-delivered ACT was generally favored over controls (5 RCTs, N = 746). At post-treatment, medium effects for pain interference and pain acceptance, and small effects for depression, mindfulness, and psychological flexibility were found. A medium effect for pain interference and acceptance, and small effects for pain intensity, depression, anxiety, mindfulness, and psychological flexibility were found at follow-up. ACT-related effects for pain interference, pain intensity, mindfulness, and anxiety increased from post-treatment to follow-up. Nevertheless, the current findings also highlight the need for more methodologically robust RCTs. Future trials should compare online ACT with active treatments, and use measurement methods with low bias.PerspectiveThis is the first meta-analytical review on the efficacy of online ACT for people with chronic pain. It comprises 5 RCTs that compared online ACT with active and/or inactive controls. Online ACT was more efficacious than controls regarding pain interference, pain intensity, depression, anxiety, mindfulness, and psychological flexibility.     

Processes of change in treatment for chronic pain: the contributions of pain, acceptance, and catastrophizing.

Cognitive-behavioral therapy has a substantial evidence base with regard to its effectiveness for individuals with chronic pain. Historically, although there has been some investigation in to the processes by which treatment succeeds or fails, few data are available regarding the unique contributions of processes from distinct cognitive behavioral approaches and how these processes may interact to affect patient functioning. The present investigation sought to evaluate three proposed process variables that have garnered empirical support within chronic pain settings, namely: pain intensity, catastrophizing, and acceptance. Participants were 252 consecutive patients who completed treatment on an interdisciplinary pain management unit. Using multiple regression, the contributions of changes in process variables to changes in treatment outcomes were assessed. In general, changes in both acceptance and catastrophizing accounted for significant variance independent of, and larger than, that accounted for by change in pain intensity. Changes in acceptance and catastrophizing accounted for roughly equivalent amounts of variance when entered immediately following changes in pain, and when entered following one another. The potential impact of these results is discussed in relation to the particular treatment delivered. Issues relating to change at the level of frequency or content of psychological experiences are considered relative to change in the functions of these experiences.     

Acceptance and Related Processes in Adjustment to Chronic Pain

Chronic pain poses significant challenges in the lives of many people. At the root of many of these challenges are the behavior patterns pain naturally coordinates. For example, in some cases, attempts to control, reduce, or cure pain through medication, medical procedures, or lifestyle changes can prove unsuccessful, and can dominate all other potential goals. The experience of chronic pain also includes other discouraging, painful, or unwanted psychological experiences, such as thoughts, feelings, and memories. Attempts to control or reduce some of these psychological experiences also can prove unsuccessful and even harmful, further reducing quality of life. This review highlights recent evidence for the utility of acceptance as an alternative when control-based methods are unsuccessful. It describes evidence from experimental, clinical, and treatment outcome studies. The review also notes how work in this area is drawing attention to the wider concept of “psychological flexibility,” an overarching process that includes other component processes, such as mindfulness and values.     

Role of psychological flexibility in parents of adolescents with chronic pain: development of a measure and preliminary correlation analyses

Parent responses to the experiences of adolescents with chronic pain are deemed important. At the same time the best ways to conceptualize, measure, and intervene with these are unclear. The purpose of the present study was to develop a measure of parent responses based on the approach proposed in Acceptance and Commitment Therapy (ACT), an approach that focuses on psychological flexibility. A total of 183 adolescents attending a specialty treatment center for chronic pain, and adults attending with them, provided the data examined in this study. Standard measures of adolescent functioning and parent responses were obtained. In addition, the attending adults, who were mostly mothers, also completed a pool of items for an instrument called the Parent Psychological Flexibility Questionnaire (PPFQ). Preliminary analyses of these items showed an internal consistency of α = 0.91. The total score for parent psychological flexibility was negatively correlated with protective and encouraging parent responses to pain, as predicted. It was also positively correlated with adolescent acceptance of pain and negatively correlated with measures of pain-related impact on their social, emotional, family, and developmental functioning. Additional analyses showed that the PPFQ yields significant unique information about adolescent functioning independent of age and gender and beyond that provided by another well-established measure of parent responses. There is increasing evidence for the effectiveness of ACT in the treatment of a range of behavior problems in adults and young people and in training for persons without identified “disorders.” It seems potentially applicable for parent training in the context of adolescent chronic pain.     

Distinctiveness of psychological obstacles to recovery in low back pain patients in primary care

Many psychological factors have been suggested to be important obstacles to recovery from low back pain, yet most studies focus on a limited number of factors. We compared a more comprehensive range of 20 factors in predicting outcome in primary care. Consecutive patients consulting 8 general practices were eligible to take part in a prospective cohort study; 1591 provided data at baseline and 810 at 6 months. Clinical outcome was defined using the Roland and Morris Disability Questionnaire (RMDQ). The relative strength of the baseline psychological measures to predict outcome was investigated using adjusted multiple linear regression techniques. The sample was similar to other primary care cohorts (mean age 44 years, 59% women, mean baseline RMDQ 8.6). The 20 factors each accounted for between 0.04% and 33.3% of the variance in baseline RMDQ score. A multivariate model including all 11 scales that were associated with outcome in the univariate analysis accounted for 47.7% of the variance in 6 months RMDQ score; rising to 55.8% following adjustment. Four scales remained significantly associated with outcome in the multivariate model explaining 56.6% of the variance: perceptions of personal control, acute/chronic timeline, illness identify and pain self-efficacy. When all independent factors were included, depression, catastrophising and fear avoidance were no longer significant. Thus, a small number of psychological factors are strongly predictive of outcome in primary care low back pain patients. There is clear redundancy in the measurement of psychological factors. These findings should help to focus targeted interventions for back pain in the future.     

A randomized, controlled trial of acceptance and commitment therapy and cognitive-behavioral therapy for chronic pain

Individuals reporting chronic, nonmalignant pain for at least 6 months (N = 114) were randomly assigned to 8 weekly group sessions of acceptance and commitment therapy (ACT) or cognitive-behavioral therapy (CBT) after a 4-6 week pretreatment period and were assessed after treatment and at 6-month follow-up. The protocols were designed for use in a primary care rather than specialty pain clinic setting. All participants remained stable on other pain and mood treatments over the course of the intervention. ACT participants improved on pain interference, depression, and pain-related anxiety; there were no significant differences in improvement between the treatment conditions on any outcome variables. Although there were no differences in attrition between the groups, ACT participants who completed treatment reported significantly higher levels of satisfaction than did CBT participants. These findings suggest that ACT is an effective and acceptable adjunct intervention for patients with chronic pain.     

The Psychological Functioning in the COVID-19 Pandemic and Its Association With Psychological Flexibility and Broader Functioning in People With Chronic Pain

Aims: People with chronic pain may be particularly vulnerable to the impact of the pandemic COVID-19, and psychological flexibility may protect them. This study investigates psychological functioning in the context of COVID-19, including fear and avoidance in the context of COVID-19, specifically its association with daily functioning, and the role of psychological flexibility, among people with chronic pain. Methods: Responses from 555 adults with chronic pain were collected through a cross-sectional online survey and analyzed. Results: Eight out of 10 participants reported significant depression and nearly 9 out of 10 reported significant functional impairment. COVID-19-related fear and avoidance significantly correlated with pain, pain-related disability, depression, and work and social adjustment (r = 18–.32), as well as psychological flexibility processes, including pain acceptance, self-as-context, and committed action, |r|=.13–.30. COVID-19-related fear and avoidance and COVID-19-related interference were significant predictors of some measures of daily functioning beyond demographics and pain, β = .09–.14. However, these associations weakened when psychological flexibility processes were factored into the models, with fear of COVID-19 no longer being a significant predictor of pain-related disability or depression, and COVID-19 avoidance no longer a significant predictor of depression. Conclusions: The psychological functioning in the context of COVID-19 appears to be negatively associated with daily functioning in people with chronic pain, and is statistically significant in this regard. Psychological flexibility may have a role in these associations for people with chronic pain in the pandemic.PerspectiveThis article demonstrates the psychological implication of COVID-19 and its association with broader emotional and daily functioning in people with chronic pain. It also demonstrates that Psychological flexibility may have a role in these associations for people with chronic pain in the pandemic.     

Acceptance of pain in adolescents with chronic pain: Validation of an adapted assessment instrument and preliminary correlation analyses

It is important to understand the processes that contribute to disability and distress in adolescents with chronic pain. For example, research has identified that when adolescents can positively adapt to the consequences of health condition, rather than attempt to change the condition itself, they also function better and experience less distress. This pattern of behavior is similar to what is referred to as “acceptance” of pain in the adult literature. Although acceptance is consistently associated with positive outcomes in adult studies, there has been less investigation of acceptance in adolescents. This study aimed to examine the reliability and validity of an adolescent‐adapted version of the Chronic Pain Acceptance Questionnaire (CPAQ‐A), and, using this instrument, to carry out a preliminary investigation of acceptance in adolescents with chronic pain. A sample of 122 highly disabled adolescents with chronic pain attending a specialty service completed the adapted CPAQ‐A. They also completed standardized measures of their pain and daily functioning. Results supported the reliability and validity of the CPAQ‐A. Correlation analyses showed that higher levels of acceptance were associated with lower levels of distress and disability, but not with lower pain intensity. Regression analyses were carried out to assess the independent contribution of acceptance after pain intensity and demographic variables were taken into account. In these analyses acceptance accounted for significant variance in disability, psychological distress, and developmental and family functioning. We discuss developmental aspects of acceptance in adolescents and clinical implications of these findings.     

The contribution of psychological flexibility to functioning in people living with cancer-related pain

Background

Studies of individuals with non-cancer-related chronic pain find that higher levels of psychological flexibility (PF) are associated with less distress, better functioning, and a better response to treatment. People diagnosed with cancer are at a significantly increased risk of developing chronic cancer-related pain, the presence of which is associated with poorer health outcomes. Little is known about whether PF is applicable to cancer pain. The current study investigates the relationship between chronic cancer-related pain, distress and functioning, and three theoretical processes proposed by the PF model: pain acceptance, present-moment focus, and committed action.

Methods

Adults (n = 246) with a cancer diagnosis (current or previous), and living in Sweden, completed an online survey involving standardized measures of cancer-related pain (intensity and impairment), depression, fatigue, PF and social stigma.

Results

Moderate to strong correlations were found between PF and all variables. In regression analyses, PF, and particularly pain acceptance, accounted for a large and significant proportion of the observed variance in depression, pain-related and overall functioning, after controlling for cancer status, pain intensity and social stigma.

Conclusion

Consistent with studies of non-cancer-related pain, higher levels of PF were strongly associated with lower levels of distress and better functioning in individuals with cancer-related pain. Further studies are needed to further explore these relationships and to determine whether psychosocial treatments targeting PF may be of benefit to people with chronic cancer-related pain.

Significance

This study explores the relationship between cancer-related pain (intensity and impairment), depression, fatigue, overall functioning, social stigma and PF. The findings suggest that higher levels of PF are associated with lower levels of distress and improved functioning in chronic cancer-related pain, after controlling for cancer status (current, in remission), pain intensity and social stigma.     

Training for general practitioners in opioid prescribing for chronic pain based on practice guidelines: a randomized pilot and feasibility trial

This study is a pilot and feasibility study that compares 2 training experiences to improve appropriate opioid prescribing for chronic pain. Both training conditions included education in relation to opioid guidelines. Following education, 1 condition included training aimed at improving psychological flexibility and the other included training in practical knowledge and skills related to pain management. Eighty-one general practitioners (GPs) took part in the study, each having been randomly assigned to 1 of the training conditions. It proved easy to recruit GPs to the training. Overall, GPs demonstrated increased knowledge of opioid prescribing for chronic pain and decreases in concerns related to prescribing following training. However, there were no changes observed in reported prescribing practices or in secondary measures of well-being. There were also no significant differences between the training conditions, other than a greater increase in intention to use prescribing guidelines in the psychological flexibility condition. Feasibility and acceptability of the training methods were generally rated high. The psychological flexibility condition was rated higher than the comparison condition in terms of interest and satisfaction. Finally, processes of psychological flexibility before and after training significantly correlated with measures of GP well-being, providing partial support for the relevance of these processes as a focus in GP training. PERSPECTIVE: A training intervention for GPs including education on opioid guidelines for chronic pain and psychological flexibility training increased knowledge of prescribing and reduced concerns but did not change prescribing behavior or well-being. The training was highly acceptable to GPs but may have been too short to produce other effects.     

Acceptance and Commitment Therapy for Chronic Pain: Evidence of Mediation and Clinically Significant Change Following an Abbreviated Interdisciplinary Program of Rehabilitation

There is an emerging body of evidence regarding interdisciplinary acceptance and commitment therapy in the rehabilitative treatment of chronic pain. This study evaluated the reliability and clinical significance of change following an open trial that was briefer than that examined in previous work. In addition, the possible mediating effect of psychological flexibility, which is theorized to underlie the acceptance and commitment therapy model, was examined. Participants included 117 completers of an interdisciplinary program of rehabilitation for chronic pain. Assessment took place at treatment onset and conclusion, and at a 3-month follow-up when 78 patients (66.7%) provided data. At the 3-month follow-up, 46.2% of patients achieved clinically significant change, and 58.9% achieved reliable change, in at least 1 key measure of functioning (depression, pain anxiety, and disability). Changes in measures of psychological flexibility significantly mediated changes in disability, depression, pain-related anxiety, number of medical visits, and the number of classes of prescribed analgesics. These results add to the growing body of evidence supporting interdisciplinary acceptance and commitment therapy for chronic pain, particularly with regard to the clinical significance of an abbreviated course of treatment. Further, improvements appear to be mediated by changes in the processes specified within the theoretical model.PerspectiveOutcomes of an abbreviated interdisciplinary treatment for chronic pain based on a particular theoretical model are presented. Analyses indicated that improvements at follow-up mediated change in the theorized treatment process. Clinically significant change was indicated in just under half of participants. These data may be helpful to clinicians and researchers interested in intervention approaches and mechanisms of change.     

Conceptual overlap of psychological constructs in low back pain

The biopsychosocial model is increasingly accepted in low back pain (LBP) research and clinical practice. In order to assess the role of psychological factors in the development and persistence of pain, a wide array of measures has been developed. Yet there is likely to be considerable conceptual overlap between such measures, and consequently, a lack of clarity about the importance of psychological factors. The aims of this study were to investigate the extent of any such overlap. An observational cohort study of 1591 LBP patients consulting in primary care completed data on a range of psychological instruments. Exploratory and confirmatory factor analyses (EFA and CFA, respectively) were carried out at the subscale level (n = 20) to investigate factor structure. The influences of the derived factors on clinical outcomes (pain intensity and self-reported disability) were then tested using linear regression. EFA yielded 4 factors, termed “Pain-related distress,” “Cognitive coping,” “Causal beliefs,” and “Perceptions of the future,” which accounted for 65.5% of the variance. CFA confirmed the validity of these factors models. The pain-related distress factor was found to have the strongest association to LBP patients’ outcomes, accounting for 34.6% of the variance in pain intensity, and 51.1% of the variance in disability. Results confirmed that considerable overlap exists in psychological measures commonly used in LBP research. Most measures tap into patients’ emotional distress. These findings help us to understand how psychological constructs relate together; implications for future research and clinical practice are discussed.     

Increased pain sensitivity among adults reporting irritable bowel syndrome symptoms in a large population-based study

The aim of this study was to examine whether irritable bowel syndrome (IBS) is associated with increased somatic pain sensitivity in a large population-based sample and to test whether this association was independent of sex, age, comorbid chronic pain, and psychological distress. Pain sensitivity tests included assessment of heat-pain threshold (N = 4054) and pressure-pain threshold (N = 4689) and of cold-pressor pain intensity and tolerance (N = 10,487). Cox regression and analysis of variance (ANOVA) were used to assess the relationship between IBS and pain sensitivity in stepwise multivariate models. The prevalence of IBS symptoms meeting the ROME II criteria was 5.3%. Compared with control subjects, IBS cases had reduced cold-pressor tolerance (hazard ratio = 1.4, P < .01), increased cold-pressor pain intensity ratings (z-score = +0.20, P < 0.01), and lower heat-pain thresholds (z-score = –0.20, P < 0.01), after adjusting for sex and age. These results were only slightly attenuated and remained significant when controlling for comorbid chronic pain and psychological distress. Results for pressure-pain threshold were not significant. Heat- and cold-pressor pain sensitivity was greatest for the IBS reporting severe chronic abdominal pain, indicating that hyperalgesia in IBS is related to degree of clinical pain rather than to the diagnosis per se. Because all pain tests were all carried out on the upper extremities, our findings indicate the presence of widespread hyperalgesia in IBS, which may be a contributing factor to the high rate of comorbid pain seen in this patient group.     

Mindfulness intervention in the management of chronic pain and psychological comorbidity: A meta-analysis

ObjectiveTo review trials on mindfulness intervention for chronic pain in primary care to clarify the evidence base and establish whether mindfulness is an important intervention for relieving pain and improving psychological comorbidity.MethodsWe performed a literature search using PubMed, the Cochrane Database, EBSCOhost, Elsevier, Wiley, Springer, and the references of retrieved articles. We included articles written in English and that were published up to January 2012. We found 428 empirical studies, but only eight were included as randomized controlled trials of mindfulness intervention for chronic pain in our meta-analysis. After extracting and synthesizing data from these eight trials, we analyzed the data extracted and synthesized from these eight trials.ResultsCompared with control intervention, mindfulness intervention had no specific effect on reducing pain intensity (weighted mean difference 3.24, 95% confidence interval [CI]: −8.92 to 2.45). Mindfulness intervention led to greater improvement in psychological comorbidity with chronic pain, such as depression (weighted mean difference −3.91, 95% CI −5.94 to −2.32) and trait anxiety (weighted mean difference −4.07, 95% CI −4.48 to −3.65).ConclusionThere is insufficient evidence that mindfulness intervention relieves pain intensity. However, it improves depression and trait anxiety in patients with chronic pain. Further research in larger, properly powered, and better-designed studies is warranted.