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.

Expression and Biological Functions of miRNAs in Chronic Pain: A Review on Human Studies

Chronic pain is a major public health problem and an economic burden worldwide. However, its underlying pathological mechanisms remain unclear. MicroRNAs (miRNAs) are a class of small noncoding RNAs that post-transcriptionally regulate gene expression and serve key roles in physiological and pathological processes. This review aims to synthesize the human studies examining miRNA expression in the pathogenesis of chronic primary pain and chronic secondary pain. Additionally, to understand the potential pathophysiological impact of miRNAs in these conditions, an in silico analysis was performed to reveal the target genes and pathways involved in primary and secondary pain and their differential regulation in the different types of chronic pain. The findings, methodological issues and challenges of miRNA research in the pathophysiology of chronic pain are discussed. The available evidence suggests the potential role of miRNA in disease pathogenesis and possibly the pain process, eventually enabling this role to be exploited for pain monitoring and management.

The Other Side of the Coin: Nocebo Effects and Psychotherapy

Psychotherapy and placebo have a long history, and both have been shown to have significant and clinically meaningful effects. In the last 100 years and up to today, psychotherapy has been subject to an enduring and often heated debate about its mechanisms and its possible relationship to placebos and their effects. However, there is little awareness of the placebo effects' counterpart-nocebo effects (from Latin "I will harm")-in the context of psychotherapy. Embedded in the controversy of whether psychotherapy and placebo share some unwanted proximity in terms of effects and mechanisms, the question arises which role nocebo effects may play in relation to psychotherapy. By using two examples, this article analyzes and discusses two different kinds of possible associations between psychotherapy and nocebo effects. We close with possibilities of how to prevent the occurrence of nocebo effects in psychotherapy, including some specific recommendations for clinical practice.

Functional neurological disorder is common in patients attending chronic pain clinics

BACKGROUND AND PURPOSE

Chronic pain is a common comorbidity in those with functional neurological disorder (FND); however, the prevalence and characteristics of FND in those with chronic pain is unknown.

METHODS

A retrospective electronic records review was made of consecutive new patients attending a chronic pain clinic of a regional service. Clinical features, medication for and outcome of chronic pain, any lifetime diagnoses of functional disorders, FND, and psychiatric disorders, and undiagnosed neurological symptoms were recorded.

RESULTS

Of 190 patients attending the chronic pain clinic, 32 (17%) had a lifetime diagnosis of FND and an additional 11 (6%) had undiagnosed neurological symptoms. Pain patients with comorbid FND were more likely to have chronic primary pain (88% with FND, 44% without FND, p < 0.0001), widespread chronic primary pain (53%, 15%, p < 0.00001), and depression (84%, 52%, p < 0.005) and less likely to have a pain-precipitating event (19% vs. 56%, p < 0.001). However, there was no significant difference between these patients in opiate prescription, benzodiazepine prescription, or pain outcome.

CONCLUSIONS

This first study of FND in a chronic pain patient population found a remarkably high prevalence of FND (17%) and is possibly an underestimation. The size of the overlap indicates that FND and chronic pain research fields are likely to have a lot to learn from each other.

Chronic Pain in the ICD-11: New Diagnoses That Clinical Psychologists Should Know About

Background

In the 10th revision of the International Classification of Diseases and Related Health Problems (ICD-10), chronic pain was not represented adequately. Pain was left undefined and not recognized as a biopsychosocial phenomenon. Instead, a flawed dualism between psychological and somatic factors was implied. Individual diagnoses were ill-defined and scattered randomly through different chapters. Many patients received diagnoses in remainder categories devoid of meaningful clinical information.

Method

The International Association for the Study of Pain launched a Task Force to improve the diagnoses for the 11th revision of the ICD and this international expert team worked from 2013-2019 in cooperation with the WHO to develop a consensus based on available evidence and to improve the diagnoses.

Results

A new chapter on chronic pain was created with a biopsychosocial definition of pain. Chronic pain was operationalized as pain that persists or recurs longer than three months and subdivided into seven categories: Chronic primary pain and six types of chronic secondary pain. All diagnoses were based on explicit operationalized criteria. Optional extension codes allow coding pain-related parameters and the presence of psychosocial aspects together with each pain diagnosis.

Conclusion

First empirical studies demonstrated the integrity of the categories, the reliability, clinical utility, international applicability and superiority over the ICD-10. To improve reliability and ease of diagnosis, a classification algorithm is available. Clinical psychologists and other clinicians working with people with chronic pain should watch the national implementation strategies and advocate for multimodal and interdisciplinary treatments and adequate reimbursement for all providers involved.

Migraine in the context of chronic primary pain, chronic overlapping pain disorders, and functional somatic disorders: A narrative review

OBJECTIVE

To contextualize migraine as the most common primary headache disorder in relation to other chronic primary pain and non-pain functional somatic and mental conditions.

BACKGROUND

Migraine is increasingly understood as a sensory processing disorder within a broader spectrum of symptom disorders. This has implications for diagnosis and treatment.

METHOD

Narrative review based on a search of the literature of the last 15 years on the overlap of migraine with other symptom disorders.

RESULTS

Migraine as the prototypical primary headache disorder not only comprises many non-headache symptoms in itself, it also shows high comorbidity with other chronic pain and non-pain conditions (e.g., fibromyalgia syndrome, irritable bowel syndrome, functional non-epileptic seizures, depression, anxiety, and posttraumatic stress disorder). Such "symptom disorders" share several etiological factors (e.g., female preponderance, psychological vulnerability) and psychophysiological mechanisms (e.g., altered sensory processing, pain expectancy). These facts are acknowledged by several recent integrative conceptualizations such as chronic primary pain, chronic overlapping pain conditions, or functional somatic disorders. Accordingly, migraine management increasingly addresses the total symptom burden and individual contributors to symptom experience, and thus incorporates centrally acting pharmacological and non-pharmacological, that is, psychological and behavioral, treatment approaches.

CONCLUSIONS

Migraine and also other primary headache disorders should be seen as particular phenotypes within a broader spectrum of symptom perception and processing disorders that require integrative diagnostics and treatment. A harmonization of classifications and better interdisciplinary collaboration are desirable.

Management of chronic primary pelvic pain syndromes

Management of chronic pelvic pain (CPP) remains a huge challenge for care providers and a major burden for healthcare systems. Treating chronic pain that has no obvious cause warrants an understanding of the difficulties in managing these conditions. Chronic pain has recently been accepted as a disease in its own right by the World Health Organization, with chronic pain without obvious cause being classified as chronic primary pain. Despite innumerable treatments that have been proposed and tried to date for CPP, unimodal therapeutic options are mostly unsuccessful, especially in unselected individuals. In contrast, individualised multimodal management of CPP seems the most promising approach and may lead to an acceptable situation for a large proportion of patients. In the present review, the interdisciplinary and interprofessional European Association of Urology Chronic Pelvic Pain Guideline Group gives a contemporary overview of the most important concepts to successfully diagnose and treat this challenging disease.

What has brain diffusion magnetic resonance imaging taught us about chronic primary pain: a narrative review

ABSTRACT

Chronic pain is a pervasive and debilitating condition with increasing implications for public health, affecting millions of individuals worldwide. Despite its high prevalence, the underlying neural mechanisms and pathophysiology remain only partly understood. Since its introduction 35 years ago, brain diffusion magnetic resonance imaging (MRI) has emerged as a powerful tool to investigate changes in white matter microstructure and connectivity associated with chronic pain. This review synthesizes findings from 58 articles that constitute the current research landscape, covering methods and key discoveries. We discuss the evidence supporting the role of altered white matter microstructure and connectivity in chronic primary pain conditions, highlighting the importance of studying multiple chronic pain syndromes to identify common neurobiological pathways. We also explore the prospective clinical utility of diffusion MRI, such as its role in identifying diagnostic, prognostic, and therapeutic biomarkers. Furthermore, we address shortcomings and challenges associated with brain diffusion MRI in chronic primary pain studies, emphasizing the need for the harmonization of data acquisition and analysis methods. We conclude by highlighting emerging approaches and prospective avenues in the field that may provide new insights into the pathophysiology of chronic pain and potential new therapeutic targets. Because of the limited current body of research and unidentified targeted therapeutic strategies, we are forced to conclude that further research is required. However, we believe that brain diffusion MRI presents a promising opportunity for enhancing our understanding of chronic pain and improving clinical outcomes.

Interstitial cystitis-an imbalance of risk and protective factors?

Interstitial cystitis (IC) presents as a chronic pain condition with variable combinations of symptoms depending on the species and individual patient. It is diagnosed by the presence of lower urinary tract signs and symptoms in combination with a variety of comorbid health problems, a history of life adversities, and the absence of other conditions that could cause the lower urinary tract signs. IC occurs naturally in humans and cats as a dimensional condition, with patients presenting with mild, moderate, and severe symptoms. Most patients appear to recover without specific treatment. A number of rodent models of IC have been used to study its causes and treatments. Unfortunately, current therapies generally fail to ameliorate IC symptoms long-term. The recent classification of IC as a chronic primary pain disorder calls for a rethinking of current clinical and research approaches to it. Beginning when a patient encounters a clinician, precipitating, perpetuating, and palliating risk factors can be addressed until a cause or reliably effective therapy is identified, and identifying predisposing and preventive factors can inform epidemiological studies and health promotion interventions. Predisposing, precipitating, and perpetuating risk factors, including environmental, psychological, and biological, increase the activity of the central threat response system (CTRS), which plays a clinically important role in IC symptoms. Studies in cats and rodent models have revealed that environmental enrichment (EE), in the absence of bladder-directed therapies, leads to amelioration of IC symptoms, implying a central role for the CTRS in symptom precipitation and perpetuation. Conceptually moving the source of IC pain to the brain as a motivational state rather than one resulting from peripheral nociceptive input offers both clinicians and researchers novel opportunities to improve care for patients with IC and for researchers to use more ecologically valid rodent models. It may even be that IC results from an excess of risk to protective factors, making this imbalance a targetable cause rather than a consequence of IC.

Social cognition abilities in patients with primary and secondary chronic pain

Previous evidence suggested that chronic pain is characterized by cognitive deficits, particularly in the social cognition domain. Recently, a new chronic pain classification has been proposed distinguishing chronic primary pain (CPP), in which pain is the primary cause of patients' disease, and chronic secondary pain (CSP), in which pain is secondary to an underlying illness. The present study aimed at investigating social cognition profiles in the two disorders. We included 38 CPP, 43 CSP patients, and 41 healthy controls (HC). Social cognition was assessed with the Ekman-60 faces test (Ekman-60F) and the Story-Based Empathy Task (SET), whereas global cognitive functioning was measured with the Montreal Cognitive Assessment (MoCA). Pain and mood symptoms, coping strategies, and alexithymia were also evaluated. Correlations among clinical pain-related measures, cognitive performance, and psychopathological features were investigated. Results suggested that CSP patients were impaired compared to CPP and HC in social cognition abilities, while CPP and HC performance was not statistically different. Pain intensity and illness duration did not correlate with cognitive performance or psychopathological measures. These findings confirmed the presence of social cognition deficits in chronic pain patients, suggesting for the first time that such impairment mainly affects CSP patients, but not CPP. We also highlighted the importance of measuring global cognitive functioning when targeting chronic pain disorders. Future research should further investigate the cognitive and psychopathological profile of CPP and CSP patients to clarify whether present findings can be generalized as disorder characteristics.

'What script am I meant to use?': a qualitative study in chronic primary pain

BACKGROUND

Chronic primary pain (CPP) as a diagnosis has been introduced in the recent International Classification of Diseases, 11th Revision (ICD-11). CPP captures the experience of pain as the primary problem, without an underlying attributable cause. Dissemination of UK guidance regarding CPP represents the first time it has been recognised as a condition in its own right. Little is known about GP views concerning caring for patients with CPP, and how related guidance is viewed and applied in practice.

AIM

To explore GP perspectives in relation to caring for people with CPP, including challenges encountered and use of related guidelines in practice.

DESIGN & SETTING

A UK-wide qualitative interview study in primary care.

METHOD

Purposive and snowball sampling were used to recruit 15 GP participants from England, Northern Ireland, Wales, and Scotland. Semi-structured interviews were undertaken and analysed using reflexive thematic analysis.

RESULTS

The following three main themes were generated: (1) 'How to start? Problematic beginnings', which referred to difficulties regarding diagnosis; (2) 'Where to go? Mapping the management challenge'; and (3) 'How to get there? Navigating strategies and response', which explored GP awareness and acceptability of UK guidelines for chronic pain. Areas identified for potential improvement included increased access to non-pharmacological management (NPM) and secondary care services, support with deprescribing, and an expanded multidisciplinary team input.

CONCLUSION

CPP is complex to both diagnose and manage. Although guidelines provide a useful framework, they pose challenges when translating into day-to-day practice.