Anger suppression and subsequent pain behaviors among chronic low back pain patients: moderating effects of anger regulation style

Associations between anger and chronic primary pain: a systematic review and meta-analysis

OBJECTIVES

Anger is a negative emotion characterized by antagonism toward someone or something, is rooted in an appraisal or attribution of wrongdoing, and is accompanied by an action tendency to undo the wrongdoing. Anger is prevalent in individuals with chronic pain, especially those with chronic primary pain. The associations between anger and pain-related outcomes (e.g., pain intensity, disability) have been examined in previous studies. However, to our knowledge, no systematic review or meta-analysis has summarized the findings of anger-pain associations through a focus on chronic primary pain. Hence, we sought to summarize the findings on the associations of anger-related variables with pain and disability in individuals with chronic primary pain.

METHODS

All studies reporting at least one association between anger-related variables and the two pain-related outcomes in individuals with chronic primary pain were eligible. We searched electronic databases using keywords relevant to anger and chronic primary pain. Multiple reviewers independently screened for study eligibility, data extraction, and methodological quality assessment.

RESULTS

Thirty-eight studies were included in this systematic review, of which 20 provided data for meta-analyses (2,682 participants with chronic primary pain). Of the included studies, 68.4% had a medium methodological quality. Evidence showed mixed results in the qualitative synthesis. Most anger-related variables had significant positive pooled correlations with small to moderate effect sizes for pain and disability.

CONCLUSIONS

Through a comprehensive search, we identified several key anger-related variables associated with pain-related outcomes. In particular, associations with perceived injustice were substantial.

Investigating Individuals’ Perceptions Regarding the Context Around the Low Back Pain Experience: Topic Modeling Analysis of Twitter Data

Background

Low back pain (LBP) remains the leading cause of disability worldwide. A better understanding of the beliefs regarding LBP and impact of LBP on the individual is important in order to improve outcomes. Although personal experiences of LBP have traditionally been explored through qualitative studies, social media allows access to data from a large, heterogonous, and geographically distributed population, which is not possible using traditional qualitative or quantitative methods. As data on social media sites are collected in an unsolicited manner, individuals are more likely to express their views and emotions freely and in an unconstrained manner as compared to traditional data collection methods. Thus, content analysis of social media provides a novel approach to understanding how problems such as LBP are perceived by those who experience it and its impact.

Objective

The objective of this study was to identify contextual variables of the LBP experience from a first-person perspective to provide insights into individuals’ beliefs and perceptions.

Methods

We analyzed 896,867 cleaned tweets about LBP between January 1, 2014, and December 31, 2018. We tested and compared latent Dirichlet allocation (LDA), Dirichlet multinomial mixture (DMM), GPU-DMM, biterm topic model, and nonnegative matrix factorization for identifying topics associated with tweets. A coherence score was determined to identify the best model. Two domain experts independently performed qualitative content analysis of the topics with the strongest coherence score and grouped them into contextual categories. The experts met and reconciled any differences and developed the final labels.

Results

LDA outperformed all other algorithms, resulting in the highest coherence score. The best model was LDA with 60 topics, with a coherence score of 0.562. The 60 topics were grouped into 19 contextual categories. “Emotion and beliefs” had the largest proportion of total tweets (157,563/896,867, 17.6%), followed by “physical activity” (124,251/896,867, 13.85%) and “daily life” (80,730/896,867, 9%), while “food and drink,” “weather,” and “not being understood” had the smallest proportions (11,551/896,867, 1.29%; 10,109/896,867, 1.13%; and 9180/896,867, 1.02%, respectively). Of the 11 topics within “emotion and beliefs,” 113,562/157,563 (72%) had negative sentiment.

Conclusions

The content analysis of tweets in the area of LBP identified common themes that are consistent with findings from conventional qualitative studies but provide a more granular view of individuals’ perspectives related to LBP. This understanding has the potential to assist with developing more effective and personalized models of care to improve outcomes in those with LBP.

When driving hurts: characterizing the experience and impact of driving with back pain

OBJECTIVES

Driving is one of the most widespread aspects of daily living to people in the United States and is an active process that requires various cognitive functions, such as attention. Chronic low back pain (CLBP) is one of the more prevalent and costly health conditions in the world, with individuals who report CLBP also reporting significant impairment across different domains of daily life both physically and cognitively. However, despite the prevalence of these two constructs, research detailing the experience of driving in pain remains largely underrepresented. This cross-sectional study sought to characterize the driving experience of people who experience CLBP, focusing on the psychological constructs related to chronic pain like pain catastrophizing, affective responses (irritability, anxiety, fear), and self-reported driving behaviors and outcomes.

METHODS

This study distributed an online questionnaire measuring pain, disability, and other psychological constructs commonly associated with CLBP like pain catastrophizing through M-turk to 307 U.S. participants with recurring CLBP and regular driving activity. Participants also answered questions regarding driving in pain, affective responses to driving in pain (i.e., irritability, anxiety, and fear), driving behaviors and violations, driving avoidance habits as a result of pain, opioid use, using pain medication while driving, and recent vehicle collisions within the past three years. Bivariate correlations were used to compare study variables, and one-way ANOVA's were used to compare means between participants with and without a collision history within the past three years.

RESULTS

Findings demonstrated significant positive associations not only between the psychological factors commonly associated with chronic pain, such as pain intensity, pain disability, pain catastrophizing, and the cognitive intrusion by pain, but also statistically significant relationships between these measures and pain intensity while driving, affective responses to driving in pain, driving violations, and driving avoidance habits. Additionally, in comparison to participants with no collision history within the past three years, participants who had been driving during a vehicle collision reported greater pain catastrophizing and cognitive intrusion by pain scores.

CONCLUSIONS

To our knowledge, the current study is the first to characterize driving experience specifically among individuals with CLBP, with attention to the relationship among key sensory, affective, and cognitive psychological metrics as well as self-reported driving history and behavior. The current findings reinforce multiple associations between pain and cognitive-affective variables that have been observed in literature outside the driving context, including pain intensity, anger, inattention, and behavioral disruption. Given that driving is a pervasive, potentially risky behavior that requires some form of cognitive focus and control, the current findings point to a continued need to examine these associations within this specific life context. We believe we have laid a groundwork for research considering the role of psychological pain variables in a driving performance. However, the nature of our analyses prevents any sort of causality from being inferred, and that future experimental research is warranted to better understand and explain these mechanisms underlying driving in pain while accounting for participant bias and subject interpretation.

How to objectively assess and observe maladaptive pain behaviors in clinical rehabilitation: a systematic search and review

Background

Cognitive-affective factors influence the perception of pain and disability. These factors can lead to pain behaviors (PB) that can persist and become maladaptive. These maladaptive PB will further increase the risk of chronicity or persistence of symptoms and disability. Thus, clinicians must be prepared to recognize maladaptive PB in a clinical context. To date, in the context of assessment in a rehabilitation setting, PB in clinical settings are poorly documented. The main objective of this study was to identify direct observation methods and critically appraise them in order to propose recommendations for practice. As a secondary objective, we explored and extracted the different observable PB that patients could exhibit and that clinicians could observe.

Methods

We conducted a comprehensive review on four databases with a generic search strategy in order to obtain the largest range of PB. For the first objective, a two-step critical appraisal used clinical criteria (from qualitative studies on barriers to implement routine measures) and psychometric criteria (from Brink and Louw critical appraisal tool) to determine which observation methods could be recommended for clinical practice. For the second objective, we extracted PB found in the literature to list potential PB that patients could exhibit, and clinicians could observe.

Results

From the 3362 retrieved studies, 47 met the inclusion criteria for the first objective. The clinical criteria allowed us to select three observation methods. After the psychometric step, two observation methods were retained and recommended for clinical practice: the Behavioral Avoidance Test-Back Pain (BAT-Back) and the Pain Behaviour Scale (PaBS). For the second objective, 107 studies met the inclusion criteria. The extraction of the PB allowed us to list a large range of PB and classify the data in 7 categories of PB.

Conclusion

Our results allowed us to recommend two observation methods for clinical practice. However, these methods have limitations and are validated only in chronic low back pain populations. With the extraction of PB presented in the literature, we contribute to better prepare clinicians to recognize PB in all patients who are experiencing pain.

Is pain catastrophizing associated with poor mobility performance and falls in older adults?

BACKGROUND

Pain catastrophizing has been associated with pain intensity and mobility limitations in adults, and may be associated with mobility problems among older adults with chronic pain. This study examined the associations between pain catastrophizing and pain characteristics, and physical performance in older people.

METHODS

The MOBILIZE Boston Study II (MBS) included 354 adults aged ≥70 years, living in the Boston area, originally enrolled in the MBS I from 2005-2008. Pain catastrophizing was measured using the 13-item Pain Catastrophizing Scale (PCS), with scores ranging from 13-65. Pain severity and pain interference were assessed by subscales of the Brief Pain Inventory. Pain distribution was classified as none, single site, and multisite. Mobility performance was assessed using the Short Physical Performance Battery (SPPB). Falls were assessed prospectively using monthly fall calendar postcards.

RESULTS

One-fourth of all participants (24 %) had high scores on the PCS (score>30). PCS was inversely associated with age and was greater among those with osteoarthritis, depression, or anxiety (p-value<0.05). PCS score was associated with global measures of pain including pain severity (p-value = 0.01), pain interference (p-value = 0.004) and multisite pain compared to no pain (p-value = 0.006). After adjusting for confounders, PCS was not associated with mobility and fall in this older population.

CONCLUSION

Although pain catastrophizing is prevalent in older adults with chronic pain, it was not associated with mobility or falls in older people. Further research is needed to determine possible long-term effects of pain catastrophizing on chronic pain and functioning in older adults.

Anger Inhibition and Pain Modulation

BACKGROUND

The tendency to inhibit anger (anger-in) is associated with increased pain. This relationship may be explained by the negative affectivity hypothesis (anger-in increases negative affect that increases pain). Alternatively, it may be explained by the cognitive resource hypothesis (inhibiting anger limits attentional resources for pain modulation).

METHODS

A well-validated picture-viewing paradigm was used in 98 healthy, pain-free individuals who were low or high on anger-in to study the effects of anger-in on emotional modulation of pain and attentional modulation of pain. Painful electrocutaneous stimulations were delivered during and in between pictures to evoke pain and the nociceptive flexion reflex (NFR; a physiological correlate of spinal nociception). Subjective and physiological measures of valence (ratings, facial/corrugator electromyogram) and arousal (ratings, skin conductance) were used to assess reactivity to pictures and emotional inhibition in the high anger-in group.

RESULTS

The high anger-in group reported less unpleasantness, showed less facial displays of negative affect in response to unpleasant pictures, and reported greater arousal to the pleasant pictures. Despite this, both groups experienced similar emotional modulation of pain/NFR. By contrast, the high anger-in group did not show attentional modulation of pain.

CONCLUSIONS

These findings support the cognitive resource hypothesis and suggest that overuse of emotional inhibition in high anger-in individuals could contribute to cognitive resource deficits that in turn contribute to pain risk. Moreover, anger-in likely influenced pain processing predominantly via supraspinal (e.g., cortico-cortical) mechanisms because only pain, but not NFR, was associated with anger-in.

Measuring anger in patients experiencing chronic pain - A systematic review

Anger is prevalent in chronic pain and has been associated with pain perception, disability, behavior and treatment outcome. Objectives were (1) to survey in the context of chronic pain the application (and omission) of validated anger self-report instruments, (2) to discuss the instruments found in the context of emotion theories and (3) to identify a possible instrument preference. A systematic search of textbooks and review articles was first performed on validated instruments designed to measure the cognitive, the motivational and the subjective feeling component of anger. Thereafter, a systematic review aimed at finding chronic pain studies from 2005 to 2019 reporting on these instruments. Textbooks and reviews listed 16 validated self-report anger measurement instruments. 28 papers applying four of these were identified and two new instruments were additionally detected. The State-Trait Anger Expression (STAXI) and its precursors were most commonly used. Studies on chronic low back pain patients prevailed. In conclusion, anger in chronic pain patients is reliably measurable at low cost with self-report tools. The STAXI-II qualifies best for this purpose based on its extensive validation history. The majority of instruments lack sufficient theoretical and psychometric adequacy. A more detailed exploration of the cognitive anger component in chronic pain patients in future research is recommended.

Relationship between anger and drug addiction potential as factors affecting the health of medical students

BACKGROUND

One of the psychobehavioral factors that can predict drug abuse in students is anger. This study aimed to evaluate the association between anger and drug addiction potential in medical students in Iran in relation to their gender and college.

MATERIALS AND METHODS

This descriptive and analytical cross-sectional study was conducted on 373 students of five colleges at Lorestan University of Medical Sciences in Iran. For collecting data, Persian versions of state-trait anger expression inventory-2 and addiction potential scale were employed. Data were analyzed in SPSS software using t-test, one-way ANOVA, and Pearson correlation test.

RESULTS

There was a significant positive relationship between subjective components of anger (sate anger, trait anger, anger expression-out, and anger expression-in) and addiction potential in samples (P < 0.05), while anger regulation components (anger control-in and anger control-out) had significant negative correlation with addiction potential (P < 0.05). Moreover, a significant difference was found in mean addiction potential scores between samples based on gender and college. With respect to mean anger scores, the difference between students based on gender was significant only in terms of state anger and anger expression-in, while we found no significant difference between them based on college except in anger expression-out (P < 0.05).

CONCLUSION

Subjective components of anger can predict drug addiction potential in medical students. It is recommended that anger management programs should be provided to the medical students as one of the most important community groups in the field of public health.

Emotion regulation in patients with somatic symptom and related disorders: A systematic review

Background

Somatic symptoms and related disorders (SSD) are prevalent phenomena in the health-care system. Disturbances in emotion regulation (ER) are commonly observed in patients suffering from SSD.

Objectives

This review aimed to examine ER processes that characterize SSD by a systematic analysis of the available empirical studies.

Data sources

PsycINFO and PubMed databases for the articles published between January 1985 and June 2018.

Search terms

“emotion/al regulation” or “affect regulation” and various forms of SSD.

Study eligibility criteria

Empirical studies that a) assigned adolescent or adult patients suffering from SSD based on a clinical diagnosis, and b) examined the relationship between ER and SSD, were included.

Study synthesis methods

A tabular summary of the articles was generated according to study characteristics, study quality, variables, and findings. The findings were organized based on ER variables used in the articles and diagnoses of SSD, which were then re-organized under the main constituents of ER (attention, body, and knowledge).

Results

The findings of the 64 articles largely supported the association between SSD and disturbances in ER, which are usually shared by different diagnoses of SSD. The results indicate that patients show a reduced engagement with cognitive content of emotions. On the other hand, bodily constituents of ER seem to depict an over-reactive pattern. Similarly, the patients tend to encounter difficulties in flexibly disengaging their (spontaneous) attention from emotional material.

Limitations

There is a scarcity of longitudinal designs, randomized controlled trials, experiments, and diary studies suited to investigate the short- and long-term causal relationship between ER and SSD. Symptoms of SSD and measures to assess emotion regulation are heterogeneous.

Conclusions and implications

Assessment of ER processes is potentially useful to understand SSD and for treatment planning. Furthermore, a concurrent investigation of the dynamic interaction of the ER modalities promises insights for better understanding of the role of ER in development, course, and maintenance of SSD.

Emotion Regulation in Chronic Disease Populations: An Integrative Review

BACKGROUND AND PURPOSE

Emotion regulation, the experiencing, processing, and modulating of emotional response, is necessary to manage the emotional stressors common in patients with chronic illness. Overwhelming emotional demands deplete the resources needed for everyday self-care management of chronic disease, contributing to poor health outcomes. Emotion regulation is shown to impact behaviors in healthy individuals; yet, a review of literature examining evidence of associations in chronically ill populations is lacking. The purpose of this article is to examine the state of the science relative to the impact of emotion regulation on health outcomes in chronic illness populations.

METHODS

Articles were reviewed (N = 14) that focused on emotion regulation and outcomes of patients with chronic illness.

RESULTS

Indicate that most of the studies focused on these concepts are cross-sectional and measure emotion regulation using various surveys. Potential relationships exist with increased age, male gender, higher education, decreased stress, depressive, and anxiety symptoms being associated with more adaptive emotion regulation. Of primary importance to patients with chronic illnesses is the potential link between greater difficulties with emotion regulation and the presence of chronic disease as well as poorer physical function.

IMPLICATIONS FOR PRACTICE

Care should include attention to affective regulation as well as physiologic responses of chronic illness.

[Issues and difficulties in the relationship between patients and caregivers in painful sickle cell vaso-occlusive crisis]

Sickle cell patients in acute pain situation experiment cognitive, behavioral and emotional changes that can accentuate their pain and disrupt communication with caregivers. On the other hand, caregivers have to face pain assessment difficulties and their own psychological reactions to their patient's pain. The gap between the patient's experience and caregiver's evaluation can lead to conflict and non-adherence treatment, and have a direct impact on the sickle cell disease prognosis. There is nothing inevitable about these phenomena, whose knowledge allows the action and opens up prospects for improving the management of sickle cell disease pain. This article is a narrative review updating the interactions between acute pain and some configurations, such as the inability to discern emotions, catastrophizing, post-traumatic stress or feeling ostracized. The overestimation of patient's addiction by caregivers also influences the pain itself. Open communication, as well as some treatments, medicated or not, a consistent institutional organization and a multidisciplinary approach altogether have an analgesic role by acting on pain cognitive and emotional components.

Trait Anger Symptoms and Emotion Regulation: The Effectiveness of Reappraisal, Acceptance and Suppression Strategies in Regulating Anger

Objective: The aim of the current study was to compare the effects of instructed cognitive reappraisal, acceptance and emotional suppression on state anger after provocation among individuals with high trait anger. The moderating effects of trait emotion regulation (ER) styles were also examined. Method: Adults (N = 102) with elevated levels of trait anger were randomised to one of three ER conditions. Participants in both the reappraisal and emotional suppression conditions reported a decline in state anger and systolic blood pressure (SBP) post-anger provocation, whereas participants in the acceptance group did not experience a substantial decline in state anger or SBP post-anger provocation. Trait suppression was further found to enhance the effects of instructed suppression, while trait tolerance augmented the effects of instructed reappraisal. Conclusions: Support was found for the use of reappraisal and emotional suppression as adaptive strategies to cope with anger arousal in the short term after provocation.

Assessing embodied interpersonal emotion regulation in somatic symptom disorders: a case study

The aim of the present study was to examine the intra- and interpersonal emotion regulation of patients with somatic symptom disorders (SSDs) during interactions with significant others (i.e., romantic partners). We presented two case couples for analysis. The first couple consisted of a patient with SSD and his healthy partner, whereas the second couple consisted of two healthy partners. The couples underwent an interpersonal experiment that involved baseline, anger and relaxation tasks. During each task, partners' cutaneous facial temperature, heart rate and skin conductance levels were measured simultaneously. Participants' trait-emotion regulation, state-affect reports for self and other, and attachment styles were also examined. The experimental phases were successful in creating variations in physiological processes and affective experience. As expected, emotion regulation difficulties predicted higher increase in the course of temperature at each phase. Besides, the patient showed restricted awareness and reflection to emotions despite his higher autonomic activity compared to healthy controls. Both partners of the first couple revealed limited ability in understanding the other's emotions, whereas the second couple performed relatively better in that domain. The temperature variations between the patient and his partner were significantly correlated while the correlations of temperature changes between the second couple were negligible except anger task. The study supported the merits of an embodied interpersonal approach in clinical studies. The tentative results of the cases were discussed in the light of findings in emotion regulation and attachment research.

Relationship between endogenous opioid function and opioid analgesic adverse effects

BACKGROUND AND OBJECTIVES

Our recent work indicates that endogenous opioid activity influences analgesic responses to opioid medications. This secondary analysis evaluated whether endogenous opioid activity is associated with degree of opioid analgesic adverse effects, and whether chronic pain status and sex affect these adverse effects.

METHODS

Using a double-blind, randomized, placebo-controlled, crossover design, 51 subjects with chronic low back pain and 38 healthy controls participated in 3 separate sessions, undergoing 2 laboratory-evoked pain tasks (ischemic and thermal) after receiving placebo, naloxone, or morphine. Endogenous opioid system function was indexed by the difference in pain responses between the placebo and naloxone conditions. These measures were examined for associations with morphine-related adverse effects.

RESULTS

Chronic pain subjects reported significantly greater itching and unpleasant bodily sensations with morphine than controls (P < 0.05). Across groups, only 6 of 112 possible associations between adverse effects and blockade effects were significant. For the ischemic task, higher endogenous opioid function was associated with greater itching (visual analog scale [VAS]; P < 0.05), numbness (tolerance; P < 0.001), dry mouth (tolerance; P < 0.05), and unpleasant bodily sensations (VAS; P < 0.05). For the thermal task, higher endogenous opioid function was associated with greater numbness (VAS; P < 0.05) and feeling carefree (VAS; P < 0.05). There were no significant main or interaction effects of chronic pain status or sex on these findings.

CONCLUSIONS

No consistent relationships were observed between endogenous opioid function and morphine-related adverse effects. This is in stark contrast to our previous observation of strong relationships between elevated endogenous opioid function and smaller morphine analgesic effects.

Anger arousal and behavioral anger regulation in everyday life among patients with chronic low back pain: Relationships to patient pain and function

OBJECTIVE

The objective of this study was to determine the degree to which patient anger arousal and behavioral anger regulation (expression, inhibition) occurring in the course of daily life was related to patient pain and function as rated by patients and their spouses.

METHOD

Married couples (N = 105) (one spouse with chronic low back pain) completed electronic daily diaries, with assessments 5 times/day for 14 days. Patients completed items on their own state anger, behavioral anger expression and inhibition, and pain-related factors. Spouses completed items on their observations of patient pain-related factors. Hierarchical linear modeling was used to test concurrent and lagged relationships.

RESULTS

Patient-reported increases in state anger were related to their reports of concurrent increases in pain and pain interference and to spouse reports of patient pain and pain behavior. Patient-reported increases in behavioral anger expression were related to lagged increases in pain intensity and interference and decreases in function. Most of these relationships remained significant with state anger controlled. Patient-reported increases in behavioral anger inhibition were related to concurrent increases in pain interference and decreases in function, which also remained significant with state anger controlled. Patient-reported increases in state anger were related to lagged increases in spouse reports of patient pain intensity and pain behaviors.

CONCLUSIONS

Results indicate that in patients with chronic pain, anger arousal and behavioral anger expression and inhibition in everyday life are related to elevated pain intensity and decreased function as reported by patients. Spouse ratings show some degree of concordance with patient reports.

Anger regulation style, anger arousal and acute pain sensitivity: evidence for an endogenous opioid "triggering" model

Findings suggest that greater tendency to express anger is associated with greater sensitivity to acute pain via endogenous opioid system dysfunction, but past studies have not addressed the role of anger arousal. We used a 2 × 2 factorial design with Drug Condition (placebo or opioid blockade with naltrexone) crossed with Task Order (anger-induction/pain-induction or pain-induction/anger-induction), and with continuous Anger-out Subscale scores. Drug × Task Order × Anger-out Subscale interactions were tested for pain intensity during a 4-min ischemic pain task performed by 146 healthy people. A significant Drug × Task Order × Anger-out Subscale interaction was dissected to reveal different patterns of pain intensity changes during the pain task for high anger-out participants who underwent pain-induction prior to anger-induction compared to those high in anger-out in the opposite order. Namely, when angered prior to pain, high anger-out participants appeared to exhibit low pain intensity under placebo that was not shown by high anger-out participants who received naltrexone. Results hint that people with a pronounced tendency to express anger may suffer from inadequate opioid function under simple pain-induction, but may experience analgesic benefit to some extent from the opioid triggering properties of strong anger arousal.

Associations between daily chronic pain intensity, daily anger expression, and trait anger expressiveness: an ecological momentary assessment study

Links between elevated trait anger expressiveness (anger-out) and greater chronic pain intensity are well documented, but pain-related effects of expressive behaviors actually used to regulate anger when it is experienced have been little explored. This study used ecological momentary assessment methods to explore prospective associations between daily behavioral anger expression and daily chronic pain intensity. Forty-eight chronic low back pain (LBP) patients and 36 healthy controls completed electronic diary ratings of momentary pain and behavioral anger expression in response to random prompts 4 times daily for 7 days. Across groups, greater trait anger-out was associated with greater daily behavioral anger expression (P<0.001). LBP participants showed higher levels of daily anger expression than controls (P<0.001). Generalized estimating equation analyses in the LBP group revealed a lagged main effect of greater behavioral anger expression on increased chronic pain intensity in the subsequent assessment period (P<0.05). Examination of a trait×situation model for anger-out revealed prospective associations between elevated chronic pain intensity and later increases in behavioral anger expression that were restricted largely to individuals low in trait anger-out (P<0.001). Trait×situation interactions for trait anger suppression (anger-in) indicated similar influences of pain intensity on subsequent behavioral anger expression occurring among low anger-in persons (P<0.001). Overlap with trait and state negative affect did not account for study findings. This study for the first time documents lagged within-day influences of behavioral anger expression on subsequent chronic pain intensity. Trait anger regulation style may moderate associations between behavioral anger expression and chronic pain intensity.