Chronic pain: a multiple-setting comparison of patient characteristics

Negative Life Events (NLEs) Contributing to Psychological Distress, Pain, and Disability in a U.S. Military Sample

Introduction

The objective was to explore how negative life events (NLEs, e.g., litigation related to pain and disability, failing most recent physical fitness test, and financial difficulties) are related to pain coping and psychological adjustment to pain in active duty military personnel.

Materials and Methods

Data were gathered as part of the Evaluation of Suicidality, Cognitions, and Pain Experience study, a DoD-funded cross-sectional assessment of chronic pain and emotional coping among a cohort of military members. The investigators examined data from 147 respondents with complete survey and pain assessment data.

Results

The sample was active duty, male (62.6%), in a relationship or married (83.0%), and had children (68.7%). The majority of the sample endorsed zero NLEs (72.0%); 23.8% endorsed one NLE, 4.2% endorsed two NLEs, and no one endorsed all three NLEs. A significantly higher proportion of participants endorsing one or more NLEs reported suicidal ideation compared to those who reported no NLEs (χ2(2) = 8.61, p = 0.014). A higher number of endorsed NLEs coincided with higher symptom severity related to psychosocial distress (depression, thwarted belongingness, perceived burdensomeness, PTSD, and suicide cognitions) and poor pain coping (rumination, helplessness, and less acceptance of chronic pain).

Conclusions

Findings revealed that NLEs may impart a significant burden on military pain sufferers. Greater numbers of endorsed NLEs are associated with increased psychosocial distress and poor pain coping. Future longitudinal studies examining long-term psychosocial distress/poor pain coping as related to NLEs would help to elaborate the long-term consequences of NLEs on pain coping and psychosocial distress.

Pain Site: How Much Does it Matter?

The medical and lay attitudes toward site of pain impressed us as being paradoxical. Though commonly used as a basic means for classifying and characterizing pain, it is not always considered in research and little is known about its psychosocial and clinical aspects. Our purpose was to examine the demographic, clinical, psychiatric, emotional, and pain-descriptive correlates of pain site, specifically in the head, upper back, and low back. The subjects were eighty-four pain patients selected randomly from two pain clinics. They were administered questionnaires assessing demographic and clinical features, trait anxiety and anger (Spielberger's STPI), inhibited anger (Kreitler and Kreitler), psychiatric tendencies (BSI, Derogatis), alexithymia, and pain experience (McGill Pain Questionnaire and Meaning Pain Scale). The results were that the three groups of patients differed in a great number of correlates that enabled a significant discrimination between them, especially good between pain in the upper and lower body parts. The psychological profiles of the groups have implications for sickness behavior (highest for low back), susceptibility to pain distraction (highest for headache), and accessibility to psychological interventions (highest for upper back). Pain site was shown to be an important factor for characterizing pain and defining the limits of generalizations about chronic pain.

Personality and pain-related beliefs/coping strategies: a prospective study

OBJECTIVES

The ways in which people adjust to chronic pain has been partly attributed to pre-existing personality traits, but most evidence to date is from cross-sectional studies and mainly with arthritis groups. The present study examined the effects of 5 personality dimensions on measures of pain-related beliefs and catastrophizing assessed 9 months apart with a heterogeneous chronic pain sample.

METHOD

One hundred forty-five patients with chronic pain presenting to a hospital pain center completed the NEO-Personality Inventory-Revised, 3 measures of pain related beliefs, the catastrophizing scale of the Coping Strategy Questionnaire, and a 0 to 10 pain scale. Nine months from the initial assessment, patients completed the same measures, apart from the NEO-Personality Inventory-Revised.

RESULTS

Of the 5 personality dimensions studied, only neuroticism was related to the pain-related variables. Multiple hierarchical regression analyses revealed that neuroticism was a significant predictor of residualized change in pain self-efficacy beliefs and pain control appraisals over the time of the study, after controlling for initial values of both constructs. However, the effects were small, suggesting that other factors play a role in the determination of such beliefs, in addition to neuroticism. In contrast, neuroticism was not a significant predictor of residualized change in catastrophizing responses over the same period. The findings provide partial support for the hypothesis that pre-existing personality traits place some patients at risk for poor adjustment to chronic pain.

Assessment of self-reported physical activity in patients with chronic pain: development of an abbreviated Roland-Morris disability scale

The Roland-Morris Disability Scale has been shown to be a reliable and valid measure of disability in persons with chronic pain. A short form with psychometric properties similar to the full scale would have numerous benefits, including decreased patient assessment burden and scoring time. On the basis of data obtained from 993 individuals with chronic pain screened for admission to a multidisciplinary pain management program, an 11-item short form of the Roland scale was developed using procedures and models from item response theory. This short form was found to be a good predictor of the 24-item parent scale and a previously published 18-item short form. The 11-item scale also demonstrated concurrent validity with measures of pain intensity and depression. Item content reflected limitations in specific functional behaviors.

PERSPECTIVE

Brief measures of important pain-related variables can be created using item response theory (IRT). In this study, a reliable and valid 11-item version of the Roland-Morris Disability Scale was created using IRT. Clinicians and researchers might consider using this scale when patient or subject assessment burden is an issue.

Cognitive-processing bias in chronic pain: a review and integration

Do patients with chronic pain selectively process pain- and illness-related stimuli? The evidence with regard to attention, interpretation, and recall biases is critically reviewed. A model is proposed to account for the findings in which it is suggested that biases in information processing in chronic pain are the result of overlap between 3 schemas: pain, illness, and self. With frequent repeated or continued experience of pain, the pain schema becomes enmeshed with illness and self-schemas. The extent of the enmeshment and the salient content of the schema determine the bias. A fundamental assumption is that all patients with pain selectively process sensory-intensity information. A clinical implication of the results is that processing biases that extend beyond this healthy and adaptive process to enmesh the self-schema with pain and illness schemas could maintain and exacerbate distress and illness behavior in patients with chronic pain.

Relations among positive affect, negative affect, and somatic symptoms in a medically ill patient sample

The Positive and Negative Affect Scale (PANAS), a brief measure of Positive and Negative Affect, may be useful in assessing mood of medical patients because it does not include somatic items frequently confounded with medical conditions. In previous research Positive and Negative Affect have been independent and uncorrelated, and Negative Affect but not Positive Affect has been positively correlated with somatic symptoms. However, relationships between variables may vary in different populations, and there is relatively little information on Positive and Negative Affect in medical patients. In the current study, the PANAS was used to assess the relationships among Positive Affect, Negative Affect, and somatic symptoms and pain in a medically ill hospital population. Positive and Negative Affect scores were positively correlated and for patients reporting pain, Positive Affect scores were positively correlated with pain intensity. Results from this and other studies indicate that Positive and Negative Affect are independent but in some populations may be correlated; positive affects such as hopefulness may co-occur with both somatic complaints and psychological distress.

Further evaluation of the pain stages of change questionnaire: is the transtheoretical model of change useful for patients with chronic pain?

Patient readiness to adopt new beliefs and coping responses to pain may predict response to multidisciplinary or cognitive-behavioral pain treatments that emphasize changes in beliefs and coping behaviors. According to the transtheoretical model of change, individuals go through specific stages in the process of changing maladaptive behaviors. Based on this model, Kerns et al. (1997) (Kerns RD, Rosenberg R, Jamison RN, Caudill MA, Haythornthwaite J. Readiness to adopt a self-management approach to chronic pain: the Pain Stages of Change Questionnaire (PSOCQ). Pain 1997;72:227-234) developed a measure of readiness to adopt a self-management approach to pain problems (the Pain Stages of Change Questionnaire; PSOCQ) and provided preliminary data supporting the validity of the measure. The current study sought to further evaluate the PSOCQ by determining the generalizability of these preliminary findings and the ability of the PSOCQ to classify persons with chronic pain into specific stages of readiness to self-manage pain. One hundred ten patients with diverse chronic pain problems, and 119 patients with fibromyalgia completed the PSOCQ and two measures of pain-related beliefs and coping prior to entry into two separate multidisciplinary pain programs. The internal consistency and concurrent validity of the PSOCQ subscales were largely replicated, supporting the validity of the subscales as measures of readiness to self-manage pain. However, the PSOCQ demonstrated less utility as a tool for classifying individuals into one of four specific stages of readiness to adopt a self-management approach. This result may be due to the classification procedure used in the current study, the characteristics of the samples in the study, specific limitations of the measure, and/or limitations in the applicability of the transtheoretical model of change to patients with chronic pain.

Psychosocial approaches to the prevention of chronic pain: the low back paradigm

Psychosocial factors have the potential to influence an acute musculoskeletal pain problem at three distinct phases: the onset of pain; the seeking and receiving of health care and income support; and the development of chronic pain-related disability and work loss. Clinical management that ignores psychosocial factors has done little to stem the flow of individuals from acute to chronic pain and disability. Psychosocial factors are no longer considered as mere secondary reactions to pain. We now recognize that psychosocial factors are usually the best predictors of chronicity, and that many of the learned behaviours apparent in chronic musculoskeletal pain have their genesis in the first few days and weeks of the problem. These circumstances have combined to shift an emphasis onto the early care provided for patients by primary care health professionals. The concept of Red Flags as signs of serious disease has been extended to the readily understood idea of Yellow Flags that indicate psychosocial barriers to recovery. For many individuals these issues need to be addressed so that the risk of developing long-term disability and work loss can be reduced. Doing this is not mutually exclusive with providing for the biomedical needs of patients.

Relationship of pain-specific beliefs to chronic pain adjustment

Cognitive-behavioral models suggest that pain patients' beliefs about their pain play a critical role in their adjustment. This study sought to replicate and extend previous research that has examined the relationship between pain-specific beliefs and adjustment to chronic pain. Two hundred forty-one chronic pain patients evaluated for possible admission to an inpatient pain treatment program completed the Sickness Impact Profile (SIP) and the Survey of Pain Attitudes (SOPA), as well as measures of pain, medical services utilization and demographic characteristics. The results indicated that the beliefs that emotions affect pain, that others should be solicitous when the patient experiences pain, and (for subjects reporting low and medium levels of pain severity) that one is disabled by pain were associated positively with psychosocial dysfunction. The beliefs that one is disabled and that activity should be avoided because pain signifies damage were associated positively with physical disability. None of the beliefs assessed was significantly associated with number of physician visits in the previous 3 months, although belief in the appropriateness of medications for managing chronic pain was associated positively with pain-related emergency room visits. The results support a cognitive-behavioral model of chronic pain adjustment and suggest specific pain beliefs to target in treatment studies examining causal relationships between beliefs and adjustment.

Chronic pain coping measures: individual vs. composite scores

Differences in the use of coping strategies have been hypothesized to explain some of the variation in adaptation among chronic pain patients. Investigators often assess coping using composite indices of different coping strategies. Although the use of composite measures has advantages, it may obscure the importance of specific coping strategies as they relate to functioning. This study compared composite with individual coping scale scores in the prediction of adjustment among chronic pain patients. One hundred and forty-one patients completed the Coping Strategies Questionnaire (CSQ) and 2 measures of adjustment (Sickness Impact Profile (SIP) and the Beck Depression Inventory (BDI)). The scales and ratings of the CSQ were factor analyzed to create composite measures, and the ability of the composite scores and individual scales to predict adjustment was compared. The results indicated that the individual scales provided more information than the composite measures regarding the relationship between coping and adjustment to chronic pain. The results also suggested that individual scale scores may be more useful than composite scores in identifying the conditions under which coping efforts have their greatest effects on adjustment.

Validity of the Sickness Impact Profile Roland scale as a measure of dysfunction in chronic pain patients

This study examined the reliability and validity of the Roland scale (taken from the Sickness Impact Profile: SIP) as a measure of dysfunction among chronic pain patients. One hundred forty-four subjects completed the SIP when they were screened for admission to an inpatient pain management program. One hundred sixteen subjects were subsequently re-administered the SIP at admission to inpatient treatment. A 3-month post-treatment administration of the SIP was performed for 52 of these subjects. Roland scale scores were calculated from the SIP for each patient. Test-retest stability coefficients indicated that the SIP Roland scale was generally as reliable as the SIP Total, Physical, and Psychosocial scale scores. Consistent with previous research, correlational analyses indicated that the SIP Roland scale is strongly associated with the SIP Physical but not the SIP Psychosocial scale. The SIP Roland scale and the other SIP scales demonstrated similar sensitivity to changes associated with multidisciplinary inpatient treatment for chronic pain. Finally, the pattern of relationships between the SIP Roland scale and several pain-related measures supported the concurrent validity of the SIP Roland scale. The results of the analyses were very similar for patients presenting with and without low back pain. The study supports the reliability and validity of the SIP Roland scale items for assessing dysfunction of chronic pain patients with pain in sites other than the low back as well as those with low back pain.

Ends of the line: diversity among chronic pain centers

Chronic pain may cause an endless search for care for its sufferers, while presenting a persistently intractable problem for physicians and disability administrators faced with an illness that defies both conventional medical thinking and established disability compensation mechanisms. In the past 15 years pain centers have mushroomed. Some pain specialists, who are typically based on these centers, have claimed to provide comprehensive treatment for chronic pain and definitive solutions to problems of disability policy. However, pain control is not yet a unified field. Approaches to treatment vary and the definitions of the objects of treatment, i.e. chronic pain syndromes, differ. This paper describes the lines of diversity which characterize this emerging field of health care through an explanatory, cross-sectional survey of 25 pain treatment facilities operating in a single urban community. Pain centers were found to vary with respect to the following dimensions: institutional affiliation, professional background of the staff, treatment modalities offered, populations served, patient selection criteria, types of pain condition treated, and diagnostic and etiologic frames of reference. Pain centers may present a diverse array of options in a pain sufferer's search for care. In addition, the reliance on pain specialists for a resolution of complex problems of disability policy may be premature.

Depression and the chronic pain experience

The present study examined the relationship between depression and a constellation of pain-related variables that describe the experience of chronic pain patients. Thirty-seven depressed and 32 non-depressed heterogeneous chronic pain patients were identified through structured interviews, use of standardized criteria and scores on the Beck Depression Inventory (BDI). The 2 groups were compared on demographic variables and scores on the Marlowe-Crowne Social Desirability scale (MC), as well as measures of disability and medication use, pain severity, interference due to pain and reported pain behaviors. The depressed group was found to be younger and to score lower on the MC than the non-depressed group. Multivariate analyses of covariance (MANCOVA), using age and MC as covariates, revealed that depressed chronic pain patients, relative to their non-depressed counterparts, reported greater pain intensity, greater interference due to pain and more pain behaviors. There were no group differences on the measures of disability and use of medications. The results provide further support for the importance of incorporating depression into clinical and theoretical formulations of chronic pain. Future use of structured interviews and standardized criteria for diagnosing depression may clarify some of the inconsistencies found in the literature.

Prevalence, onset, and risk of psychiatric disorders in men with chronic low back pain: a controlled study

This study used structured diagnostic interviews and DSM-III criteria to assess lifetime prevalence and pre-morbid risk of psychiatric disorder in a sample of men with long-standing chronic back pain (CLPB) attending a primary care clinic. A control group of age and demographically matched men without history of back pain was also studied. Compared to controls, men with CLBP had significantly higher lifetime rates of major depression (32% vs. 16%), alcohol use disorder (64.9% vs. 38.8%), and a major anxiety disorder (30.9% vs. 14.3%). Almost all CLBP men ever experiencing a mood disorder reported recurrent, not single, episodes. The 6 month point prevalence of major depression, but not other disorders, was also significantly elevated for men with CLBP. In CLBP, the first episode of major depression generally (58.1%) followed pain onset. While the initial major depressive episode usually commenced within the first 2 years of established pain, late onset mood disorder was also common. By comparison in most cases (81%) onset of alcohol use disorders considerably preceded pain. When an age-matching procedure was used to gauge relative vulnerability to psychiatric illness in patients and controls, CLBP patients had significantly higher pre-pain rates of alcohol use disorder but not depression. After age of pain onset, CLBP subjects had over 9 times the risk of developing major depression, but had similar rates of developing alcoholism. We conclude that (1) alcohol use disorders rather than depression may increase risk of developing CLBP, and (2) risk of new onset and recurrent major depression remains high for men throughout their pain career. This suggests that psychological adaptation to long-standing pain may be less successful than previously thought, especially with regard to recurrent mood disorder.

Psychological events are both risk factors in, and consequences of, chronic pain

This study questioned 2 assumptions often inherent in psychogenic explanations of pain: (1) that a relationship exists between pain and life events predating pain onset, and (2) that pain patients are a psychologically homogeneous group. Chronic pain sufferers in multiple settings and control subjects participated in this study in which the relationships between pain and 20 psychological variables were examined. Pain was defined and assessed in 3 different ways: (1) membership in a pain group, (2) number of specialists consulted for pain, and (3) pain intensity. Of the 20 psychological variables examined, only less emotional repression and greater "ergomania" (excessive work) were consistently associated with pain on all 3 pain criteria. In addition, pain patients were more likely to have had a relative with pain. Comparisons of pain patients in different settings showed that pain clinic patients reported having been more active throughout their lives, but were currently more depressed and experienced less life satisfaction than patients who were not in a specialized pain centre. These results are interpreted in the light of current multicausal views of pain and conclusions are drawn about the role of psychological variables both as risk factors in, and as consequences of pain.

Dimensions of pain-related cognitive coping: cross-validation of the factor structure of the Coping Strategy Questionnaire

Previous research has demonstrated a relationship between cognitive pain coping activity and adjustment in pain patients. The empirically derived dimensions of coping activity, as measured by scales from the Coping Strategy Questionnaire (CSQ), however, have varied across investigations. The purpose of this investigation was to determine both the content and number of dimensions of the CSQ and to explore the potential moderating influence that sociodemographic and patient history variables may have on the latent structure of the CSQ. A total of 620 patients from 5 different chronic pain patient samples were used to assess the generalizability of the dimensions across samples. Confirmatory factor analytic procedures identified a 3-factor solution in most of the samples that was robust across various demographic characteristics. Two factors appeared particularly robust: one reflected conscious use of cognitive coping strategies (with high loadings on ignoring pain and coping self-statements) and another reflected self-efficacy beliefs concerning pain (with high loadings on ability to control and decrease pain). A third factor, which was somewhat less stable, appeared to reflect avoidance of pain by attention to non-pain-related mental activity (with high loadings on diverting attention and praying and hoping). Scales reflecting catastrophizing cognitions and behavioral coping strategies did not consistently load on the above dimensions. Issues concerning the conceptualization and measurement of pain-related cognitive coping dimensions are discussed.

Neglected factors in chronic pain treatment outcome studies--referral patterns, failure to enter treatment, and attrition

An increasing number of chronic pain treatment outcome studies have appeared in the literature. In general, these studies support the efficacy of multidisciplinary pain programs, as well as specific treatment modalities such as biofeedback and relaxation. Reviews of this literature have tended to be cautiously optimistic. Some concerns, however, have been raised about the methodological adequacy of these studies, particularly in terms of the lack of control groups, the brief duration of follow-up periods, and the vague criteria used for establishing the success of the therapeutic interventions. Other factors that mitigate conclusions regarding the generalizability of the favorable results reported need to be considered. In this paper 3 rarely discussed topics that are implicit within most treatment outcome studies and that need to be given greater attention are examined. These topics include: (1) referral patterns to pain clinics (who are referred to pain clinics, when, and how representative is the referred sample?); (2) failure to enter treatment (e.g., exclusion criteria, lack of available financial support to cover the cost of treatment, patient's refusal to accept recommendations), and consequently, the representativeness of the treated sample; and (3) patient's attrition. In this paper we discuss each of these factors as they underscore important qualifications that have to be made in evaluating treatment outcome studies.

Quantification of biomedical findings of chronic pain patients: development of an index of pathology

Difficulties in assessing and quantifying the biomedical signs and symptoms that may be related to patients' reports of pain are well recognized. Although there appears to be some consensus among physicians as to the potential utility of examination and diagnostic tests frequently used to evaluate chronic pain patients, little attention has been paid to the reliability of interpreting the results of these procedures. Moreover, the integration of biomedical findings to form a general index of pathology associated with chronic pain has been a difficult problem to solve because not all biomedical procedures used to evaluate pain patients are necessarily relevant or indicated for a specific patient. Two studies are presented that were designed to evaluate the reliability of 23 biomedical procedures commonly used to evaluate chronic pain patients and to determine if findings on these procedures can effectively be combined to form a reliable index of physical pathology. The results of study 1 suggest that 17 of the 23 procedures can be applied in clinical setting with acceptable levels of reliability. Study 2 provides evidence that an innovative weighted scoring approach, based on current medical consensus, can be used to produce a reliable, general index of pathology that is independent of the number of procedures used to evaluate patients. The utility of this quantification approach to biomedical findings for clinical and research purposes is discussed.

Chronic pain and depression: toward a cognitive-behavioral mediation model

Although considerable attention has recently been devoted to explaining why depression is a frequent concomitant of chronic pain, little empirical work has been conducted to test predictions based on these models. The present study was designed to test a cognitive-behavioral mediation model of pain and depression that proposes perceived reduction in instrumental activities along with a decline in perceptions of control and personal mastery are necessary prerequisites for the development of depressive symptomatology in pain patients. According to this model, in contrast to alternative models, the presence of pain is not sufficient condition for the subsequent development of depression. This model was tested and confirmed through the application of structural modeling with latent variables. Specifically, the direct link between pain and depression was found to be non-significant, however, measures of perceived life interference and self-control were found to be significant intervening variables between pain and depression. These results provide the first empirical demonstration that psychological mediators may be involved in the development of depression secondary to chronic pain. The findings of this study are contrasted with single-factor models that postulate both chronic pain and depression as resulting from a common cause.

Differential utility of medical procedures in the assessment of chronic pain patients

Physicians are frequently called upon to evaluate patients with chronic pain to (1) establish the etiology, (2) determine the extent of impairment and disability, and (3) prescribe treatment. In many cases, there is little agreement as to what evaluation procedures should be used or how to weight and integrate these findings. Two studies were conducted to determine the domain of procedures pain specialists believe are most important in evaluation and the clinical utility of each. A survey of 75 physicians specializing in the treatment of chronic pain was conducted. Coefficients of concordance indicated that physicians displayed substantial agreement as to the differential utility of 18 physical examination and diagnostic procedures. The relevance of each of these procedures in the assessment of 100 pain patients was evaluated. Differential weights for each procedure derived from the survey were highly correlated with clinical practice. The results of the present studies provide a basis for development of a standardized assessment procedure that incorporates statistically derived weights to quantify medical findings.

Risk of misinterpretation of MMPI Schizophrenia scale elevations in chronic pain patients

Seventy-three chronic pain patients with elevated MMPI Schizophrenia (Sc) scale scores (T score greater than 70) were compared with 55 psychotic and 87 non-psychotic psychiatric patients with elevated Sc scores to examine group differences in item content patterns on the Harris and Lingoes subscales. Chronic pain patients evidenced lower scores on all Harris and Lingoes Sc subscales, except for the Bizarre Sensory Experiences subscale on which they scored significantly higher than the psychiatric groups. Results demonstrate that Sc is elevated in many chronic pain patients because they endorse somatic symptoms and items suggestive of depression and inertia, whereas psychotics endorse more items reflecting bizarre and disordered thinking, social alienation and defective inhibition, and non-psychiatric patients endorse more depression, despair, thought disorganization and social alienation. These data suggest that high Sc scores of many chronic pain patients reflect symptoms and sequelae of their physical problems, and do not necessarily reflect severe psychopathology.

IASP taxonomy of chronic pain syndromes: preliminary assessment of reliability

Communication and consequently advancement of knowledge in understanding and treatment of chronic pain has been hindered by the absence of a taxonomy of chronic pain syndromes. Recently the IASP Subcommittee on Taxonomy proposed a classification method based on a multiaxial system. In the present study the interjudge reliability of 2 of the 5 axes, body location and presumed etiology are evaluated. Overall, axis I demonstrated good reliability, however, the reliability of several categories contained within this axis were low enough to suggest minor changes to this axis may increase its clinical utility. Axis V was found to have only fair reliability and many of the categories comprising this axis were demonstrated to have reliabilities that are not clinically acceptable. The implications of these results for future development and refinement of the IASP taxonomy are discussed.