The IASP classification of chronic pain for ICD-11: chronic cancer-related pain

Utilization of Magnesium for the Treatment of Chronic Pain

CONTEXT

The International Association for the Study of Pain (IASP) defines chronic pain as pain that persists or recurs for longer than 3 months. Chronic pain has a significant global disease burden with profound effects on health, quality of life, and socioeconomic costs.

EVIDENCE ACQUISITION

Narrative review.

RESULTS

There are several treatment options, including pharmacological therapy, physical rehabilitation, psychological therapies, and surgical interventions, for chronic pain management. Magnesium has been FDA-approved for several indications including hypomagnesemia, arrhythmia, prevention of seizures in eclampsia/preeclampsia, and constipation. Magnesium has been used for numerous off-label uses, notably for acute and chronic pain management. The mechanism of magnesium in pain management is primarily through its action as a voltage-gated antagonist of NMDA receptors, which are involved in pain transduction.

CONCLUSIONS

This narrative review will focus on the current evidence and data surrounding the utilization of magnesium as a treatment option for chronic pain.

Animal Models of Cancer-Related Pain: Current Perspectives in Translation

The incidence of pain in cancer patients during diagnosis and treatment is exceedingly high. Although advances in cancer detection and therapy have improved patient prognosis, cancer and its treatment-associated pain have gained clinical prominence. The biological mechanisms involved in cancer-related pain are multifactorial; different processes for pain may be responsible depending on the type and anatomic location of cancer. Animal models of cancer-related pain have provided mechanistic insights into the development and process of pain under a dynamic molecular environment. However, while cancer-evoked nociceptive responses in animals reflect some of the patients’ symptoms, the current models have failed to address the complexity of interactions within the natural disease state. Although there has been a recent convergence of the investigation of carcinogenesis and pain neurobiology, identification of new targets for novel therapies to treat cancer-related pain requires standardization of methodologies within the cancer pain field as well as across disciplines. Limited success of translation from preclinical studies to the clinic may be due to our poor understanding of the crosstalk between cancer cells and their microenvironment (e.g., sensory neurons, infiltrating immune cells, stromal cells etc.). This relatively new line of inquiry also highlights the broader limitations in translatability and interpretation of basic cancer pain research. The goal of this review is to summarize recent findings in cancer pain based on preclinical animal models, discuss the translational benefit of these discoveries, and propose considerations for future translational models of cancer pain.

Involvement of relatives in chronic non-malignant pain rehabilitation at multidisciplinary pain centres: part one - the patient perspective

OBJECTIVES

Chronic non-malignant pain (CNP) is a significant healthcare problem with considerable consequences for patients, relatives and society. CNP is a lifelong condition that calls for acceptance and self-management. Existing research indicates that the involvement of relatives improves patients' and relatives' management of CNP, but the area is, at present, scarcely described. Research is required to obtain knowledge about the patients' experiences, needs and preferences concerning the involvement of their relatives within the frame of CNP rehabilitation, which is the aim of this study.

METHODS

The study applied a qualitative phenomenological-hermeneutic design conducting individual interviews with 10 patients with CNP from three selected Multidisciplinary Pain Centres (MPC). The analysis was guided by Paul Ricoeur's philosophy of interpretation of the text.

RESULTS

The findings illuminated the patients' perspectives on the involvement of relatives within three key themes, each having two or three sub-themes. The analysis revealed that patients in CNP rehabilitation had various interpretations of the substance of involving relatives, reflecting their sparse experiences. It seemed arbitrary, who during the rehabilitation actually experienced the involvement of their relatives, leaving the impression of an area short of structure. This shortage was troublesome, due to a heartrending impact of CNP. Patients' reduced functional level, combined with their surroundings difficulties in grasping the magnitude of CNP led to a loss of relationships and a risk of social isolation. Patients' close relationships became essential but were under pressure as well. Patients living with a spouse/cohabitant experienced that the relationship was affected by a disrupted balance and pain-related emotional outbursts. The patients experienced a profound need for being understood, but the text also revealed a need for mutual understanding to acknowledge the relatives' strain as well. Particular patients with children living at home experienced to be under great strain, complicated by a deep concern for long-term consequences for their children growing up influenced by parental CNP. Experienced involvement of relatives, even to a minor extend was perceived as beneficial for the patients, who experienced increased understanding and support from the relatives. However, due to the lack of a structured service, the patients' access to the involvement of relatives became dependent on their ability to define their need and pick it out. Thus the patients also expressed a general preference for mandatory and structured involvement, yet tailored to the specific patient.

CONCLUSIONS

The study showed an overwhelming need for the involvement of relatives among patients with CNP, indicating that increased attention and investigation of relevant interventions are required. Despite differences between the MPC, our primary impression was that the involvement of relatives reached a minimal level of what was expected, which might entail desertion of patients scarce of resources. Individualised adjusted involvement of relatives is assumed to improve patient's management of CNP in everyday life. A family systems nursing (FSN) approach is a relevant proposal for intervention, useful in other illness areas. Still, research needs to shed light on the appropriateness of FSN when involving relatives in the rehabilitation of CNP.

Not All Pain is Created Equal: Basic Definitions and Diagnostic Work-Up

Chronic pain is considered a public health priority by the World Health Organization and European health institutions. It has reached alarming proportions in terms of disability, consumption of health and social resources, and impact on primary and specialist care services. Primary care physicians are often called on to manage this condition. Chronic pain management can be challenging due to its complexity. It has traditionally been considered to include nociceptive pain that that persists longer than the normal healing time, neuropathic pain lasting more than 3 months, or a combination of these. More recently, a third descriptor, nociplastic (primary) pain, was added to classify patients with chronic pain conditions such as fibromyalgia, nonspecific back pain, or mixed pain that persists or other conditions in which altered central pain modulation results in central sensitization and chronic pain in the absence of actual or threatened damage to tissues, including in the somatosensory nervous system. This document provides an overview of pain types and their underlying mechanisms. Successful pain management is facilitated by identification of the pain type. A set of diagnostic tools and a pain algorithm are presented to guide the clinician toward the correct diagnosis. The algorithm identifies cases that may require referral to a pain specialist. Once the site of origin of the pain (the "pain generator") is identified, or a primary pain syndrome is suspected, the accompanying article provides information and rationale to support treatment decisions based on patient characteristics.

Antinociceptive effect of triterpene acetyl aleuritolic acid isolated from Croton zehntneri in adult zebrafish (Danio rerio)

Croton zehntneri is a plant known as canelinha de cunhã, prevalent in the northeast region of Brazil. Many constituents of the vegetable have already been studied, and their pharmacological properties have been proven, but this is the first study to analyze the antinociceptive effect in adult zebrafish (ZFa) of the triterpene acetyl aleuritolic acid (AAA) isolated from the stem bark. The animals (ZFa; n = 6/group) were treated intraperitoneally (ip; 20 μL) with AAA (0.1 or 0.3 or 1.0 mg/mL) or vehicle (0.9% saline; 20 μL), and submitted to the locomotor activity test, as well as 96 h acute toxicity. Other groups (n = 6/each) received the same treatments and underwent acute nociception tests (formalin, cinnamaldehyde, glutamate, acid saline, capsaicin, and hypertonic saline). Possible neuromodulation mechanisms were evaluated. AAA (0.1 or 0.3 or 1.0 mg/mL) reduced the nociceptive behavior induced by acid saline and capsaicin, as well as inhibited corneal nociception induced by hypertonic saline, both without altering the animals' locomotor system and without toxicity. These analgesic effects of AAA were significantly (p > 0.05) similar to those of morphine, used as a positive control. The antinociceptive effect of AAA was inhibited by methylene blue, ketamine, camphor, ruthenium red, amiloride, and mefenamic acid. The antinociceptive effect of AAA on the cornea of animals was inhibited by capsazepine. Therefore, AAA showed pharmacological potential for the treatment of acute pain, and this effect is modulated by cGMP, NMDA receptors, transient receptor potential channels (TRPs), ASICs and has pharmacological potential for the treatment of corneal pain modulated by the TRPV1 channel.

Neuropathic pain in children: Steps towards improved recognition and management

Neuropathic pain in children can be severe and persistent, difficult to recognise and manage, and associated with significant pain-related disability. Recognition based on clinical history and sensory descriptors is challenging in young children, and screening tools require further validation at older ages. Confirmatory tests can identify the disease or lesion of the somatosensory nervous system resulting in neuropathic pain, but feasibility and interpretation may be influenced by age- and sex-dependent changes throughout development. Quantitative sensory testing identifies specific mechanism-related sensory profiles; brain imaging is a potential biomarker of alterations in central processing and modulation of both sensory and affective components of pain; and genetic analysis can reveal known and new causes of neuropathic pain. Alongside existing patient- and parent-reported outcome measures, somatosensory system research methodologies and validation of mechanism-based standardised end-points may inform individualised therapy and stratification for clinical trials that will improve evidence-based management of neuropathic pain in children.

Genetic implications in quality palliative care and preventing opioid crisis in cancer-related pain management

The prevalence of cancer-related pain is 64% among patients with metastatic, advanced, or terminal cancer, 59% among patients undergoing anticancer treatment, and 33% among patients who completed curative treatment. According to the World Health Organization cancer pain relief guidelines, opioid analgesics are the mainstay analgesic therapy in addition to conventional first-step analgesics, such as non-steroidal anti-inflammatory drugs and acetaminophen. The indications for strong opioids have recently been expanded to include mild-to-moderate pain in addition to moderate-to-severe pain. The U.S. Centers for Disease Control and Prevention guidelines emphasize that realistic expectations should be weighed against potential serious harm from opioids, rather than relying on the unrealized long-term benefits of these drugs. Therefore, treatment strategies for both cancer-related chronic or acute pain have been unfortunately deviated from opioid analgesics. The barriers hindering adequate cancer-related pain management with opioid analgesics are related to the inadequate knowledge of opioid analgesics (e.g., effective dose, adverse effects, and likelihood of addiction or tolerance). To achieve adequate opioid availability, these barriers should be overcome in a clinically suitable manner. Genetic assessments could play an important role in overcoming challenges in opioid management. To balance the improvement in opioid availability and the prevention of opioid misuse and addiction, the following two considerations concerning opioids and genetic polymorphisms warrant attention: (A) pain severity, opioid sensitivity, and opioid tolerance; and (B) vulnerability to opioid dependence and addiction.

Nonopioid drug combinations for cancer pain: protocol for a systematic review

This protocol will guide a review of clinical trials that evaluate the efficacy and safety of nonopioid analgesic drug combinations for the management of cancer-related pain.

Introduction:

Pain related to cancer, and its treatment, is common, may severely impair quality of life, and imposes a burden on patients, their families and caregivers, and society. Cancer-related pain is often challenging to manage, with limitations of analgesic drugs including incomplete efficacy and dose-related adverse effects.

Objectives:

Given problems with, and limitations of, opioid use for cancer-related pain, the identification of nonopioid treatment strategies that could improve cancer pain care is an attractive concept. The hypothesis that combinations of mechanistically distinct analgesic drugs could provide superior analgesia and/or fewer adverse effects has been tested in several pain conditions, including in cancer-related pain. Here, we propose to review trials of nonopioid analgesic combinations for cancer-related pain.

Methods:

Using a predefined literature search strategy, trials—comparing the combination of 2 or more nonopioid analgesics with at least one of the combination's individual components—will be searched on the PubMed and EMBASE databases from their inception until the date the searches are run. Outcomes will include pain intensity or relief, adverse effects, and concomitant opioid consumption.

Results/Conclusions:

This review is expected to synthesize available evidence describing the efficacy and safety of nonopioid analgesic combinations for cancer-related pain. Furthermore, a review of this literature will serve to identify future research goals that would advance our knowledge in this area.

A retrospective observational study comparing somatosensory amplification in fibromyalgia, chronic pain, psychiatric disorders and healthy subjects

OBJECTIVES

Somatosensory amplification (SA) has been described as an important feature of somatoform disorders, and an "amplifying somatic style" has been reported as a negative connotation of body perception. As widespread pain (WSP) in fibromyalgia (FM) is due to a central sensitization (CS) rather than organic alterations, there has been discussion as to whether FM is equivalent to or distinct from somatization disorder (SD). Assuming SD and FM are two distinct entities, an increase in somatic amplification should be expected only in subjects who have SD, regardless of the type of pain they experience. Purpose of the study was to explore the magnitude of SA in FM, and whether this depends on the association with SD.

METHODS

FM (n=159) other forms of chronic pain (OCP, n=582), psychiatric (Psy, n=53) and healthy (H, n=55) subjects were investigated using the Somatosensory Amplification Scale (SSAS), Illness Behavior Questionnaire, (IBQ), Italian Pain Questionnaire (IPQ), and Cold Pressor Test (CPT) in a retrospective observational study.

RESULTS

FM subjects displayed higher SSAS scores than the other groups. High SSAS score was associated with FM (OR=8.39; 95%CI: 5.43-12.46) but not OCP. Although FM has the highest prevalence of SD (x²=14.07; p=.007), high SSAS scores were associated with SD in OCP but not in FM.

CONCLUSIONS

Unlike in OCP, in FM high SSAS scores were independent of the presence of SD. From a biopsychosocial perspective, SSAS may be a factor associated with the onset of FM.

An Overview of Current Recommendations and Options for the Management of Cancer Pain: A Comprehensive Review

It is estimated that one-third of oncologic patients in the USA do not receive analgesia proportional to or adequate for the intensity of their pain. A mechanism-based approach to oncologic pain therapy is critical to ensure that analgesia regimens are individualized and effective. Since the mechanisms that lead to cancer pain are complex, healthcare providers must be willing to elicit and recognize the symptoms of each individual patient since these factors influence both the experience of pain and response to treatment. This process is centered on the use of detailed history in order to understand symptom expression in the context of primary tumor diagnosis and progression, history of cancer pain, psychological distress, sleep disturbances, cognitive function, and addictive behavior. Incorporating all of these factors into the assessment of a patient's pain condition can facilitate management decisions and help predict patient response to treatment.

Dietary Patterns and Interventions to Alleviate Chronic Pain

Pain is one of the main problems for modern society and medicine, being the most common symptom described by almost all patients. When pain becomes chronic, the life of the patients is dramatically affected, being associated with significant emotional distress and/or functional disability. A complex biopsychosocial evaluation is necessary to better understand chronic pain, where good results can be obtained through interconnected biological, psychological, and social factors. The aim of this study was to find the most relevant articles existent in the PubMed database, one of the most comprehensive databases for medical literature, comprising dietary patterns to alleviate chronic pain. Through a combined search using the keywords "chronic pain" and "diet" limited to the last 10 years we obtained 272 results containing the types of diets used for chronic pain published in the PubMed database. Besides classical and alternative methods of treatment described in literature, it was observed that different diets are also a valid solution, due to many components with antioxidant and anti-inflammatory qualities capable to influence chronic pain and to improve the quality of life. Thirty-eight clinical studies and randomized controlled trials are analyzed, in an attempt to characterize present-day dietary patterns and interventions to alleviate chronic pain.

Evaluation of the International Classification of Diseases-11 chronic pain classification: study protocol for an ecological implementation field study in low-, middle-, and high-income countries

Introduction

The purpose of the present ecological implementation field study is to evaluate the new classification of chronic pain as implemented in the 11th revision of the International Classification of Diseases (ICD-11) with regard to clinical utility and interrater reliability. To evaluate the classification in a variety of settings, the study will be implemented in different low-, middle-, and high-income countries.

Methods

The study will be conducted in 2 phases. Participating pain clinics of the first phase are located in India, Cuba, and New Zealand. Two or more clinicians per study center will use the ICD-11 classification of chronic pain to diagnose 75 to 100 consecutive new chronic pain patients per center. A structured classification algorithm will guide the diagnostic process. Interrater reliability will be analyzed for the first 20 consecutive new patients per center. Before the coding, a training workshop will introduce the clinicians to the new classification. The main outcome parameter of the ecological implementation field study is clinical utility. More specifically, this entails clinical utility ratings, interrater reliability, as well as the exhaustiveness of the classification and the mutual exclusiveness of the new chronic pain categories. Differences between countries with different cultural backgrounds and income levels will be analyzed.

Perspective

The ecological implementation field study presented here will be implemented in several countries with different income levels. This increases the generalizability of the results and allows initial insight into the global applicability of the new chronic pain classification. A positive evaluation can facilitate the implementation of the classification.

A protocol for a systematic review and meta-analysis to identify measures of breakthrough pain and evaluate their psychometric properties

INTRODUCTION

Breakthrough pain is common in children and adults with cancer and other conditions, including those approaching end-of-life, although it is often poorly managed, possibly partly due to a lack of validated assessment tools. This review aims to (1) identify all available instruments measuring breakthrough pain in infants, children, adolescents or adults and (2) critically appraise, compare and summarise the quality of the psychometric properties of the identified instruments using COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) criteria.

METHODS AND ANALYSIS

Two searches will be carried out between October 2019 and January 2020, one for each aim of the review. The Cochrane Library, International Prospective Register of Systematic Reviews, Embase, Cumulative Index of Nursing and Allied Health Literature, Medical Literature Analysis and Retrieval System Online (MEDLINE), PsycINFO, Web of Science Core Collection, Google Scholar, the ProQuest Dissertations & Theses Database, Evidence Search and OpenGrey databases will be searched from database inception until the date the search is conducted. Reference lists of eligible articles will be screened and authors in the field contacted. For search 1, articles will be screened by two reviewers by abstract, and full-text where necessary, to identify if a breakthrough pain assessment was used. Search 2 will then be conducted to identify studies evaluating measurement properties of these assessments. Two reviewers will screen articles from search 2 by title and abstract. All potentially relevant studies will be screened by full text by both reviewers. For search 2, data will be extracted in parallel with the quality assessment process, as recommended by COSMIN. Two reviewers will assess methodological quality using the COSMIN Risk of Bias checklist and the COSMIN updated criteria for good measurement properties. Findings will be summarised and, if possible, data will be pooled using meta-analysis. The quality of the evidence will be graded and summarised using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) guidelines.

ETHICS AND DISSEMINATION

Results of this review will be submitted for publication in a peer review journal and presented at conferences.

PROSPERO REGISTRATION NUMBER

CRD42019155583.

Transcriptomic analysis of long noncoding RNAs and mRNAs expression profiles in the spinal cord of bone cancer pain rats

Bone cancer pain (BCP) is one of the most common types of chronic cancer pain and its pathogenesis has not been fully understood. Long non-coding RNAs (lncRNAs) are new promising targets in the field of pain research, however, their involvements in BCP have not been reported. In the present study, we established the BCP model by implantation of Walker 256 carcinoma cells into rats' tibial medullary cavity and performed transcriptome sequencing of the ipsilateral lumbar spinal cord to explore changes in expression profiles of lncRNA and mRNA. We identified 1220 differently expressed mRNAs (DEmRNAs) (1171 up-regulated and 49 down-regulated) and 323 differently expressed lncRNAs (DElncRNAs) (246 up-regulated and 77 down-regulated) in BCP model, among which 10 DEmRNAs (5 up-regulated and 5 down-regulated) and 10 DElncRNAs (5 up-regulated and 5 down-regulated) were validated the expression by RT-qPCR. Then, we performed Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis on the expression of DEmRNAs and DElncRNAs, showing that they were mainly enriched in inflammatory and immunologic processes/pathways. Finally, we constructed a co-expression network and a ceRNA network of DEmRNAs and DElncRNAs to exhibit a potential regulatory mechanism of DElncRNAs, directly regulating protein coding gene expression in cis or in trans and indirectly regulating protein coding gene expression by sponging miRNA. In conclusion, our study provided a landscape of dysregulated lncRNA and mRNA in spinal cord of bone cancer pain and detected novel potential targets for treatment in the future.

Evaluation of self-efficacy determinants in community-dwelling older adults with chronic musculoskeletal pain

INTRODUCTION: Self-efficacy is defined as the strength of a person’s convictions in being able to perform a given activity and obtain the expected result. It may act as a potent mediator between chronic musculoskeletal pain and how older adults cope with their disabilities. OBJECTIVE: To evaluate the determinants of self-efficacy beliefs and fear of physical exercise in community-dwelling older adults with chronic musculoskeletal pain. METHODS: This cross-sectional study recruited older adults with chronic musculoskeletal pain. Only individuals living in an urban area in southern Brazil and who reported pain for more than 3 months were included. A convenience sample was selected in a nonprobabilistic fashion. The study variables consisted of sociodemographic data; pain based on the Brief Pain Inventory and the Leeds Assessment of Neuropathic Symptoms and Signs for Patients with Chronic Pain; and self-efficacy based on the Chronic Pain Self-Efficacy Scale. Also, simple questions were created for physical exercise beliefs. For statistical analysis, absolute and relative frequency, χ2 test, and Mann-Whitney U test were used as appropriate. RESULTS: The sample consisted of 193 older adults, mostly women with low level of education. Self-efficacy was best rated by older adults living alone and by those who were classified as exclusively nociceptive pain. CONCLUSION: Despite having chronic pain, older adults with higher self-efficacy feel confident in performing their tasks and have greater ability to cope with changes related to aging and to engage in self-care.

Pain acceptance in cancer patients with chronic pain in Hunan, China: A qualitative study

Objective

The purpose of this qualitative study was to describe the experiences of pain acceptance in Chinese cancer patients with chronic pain.

Methods

Twelve hospitalized cancer patients with chronic pain participated in this qualitative descriptive study from August to November 2017. In-person semi-structured interviews were conducted, recorded, transcribed, and analyzed using Colaizzi's seven-step method.

Results

The following four main themes and 15 subthemes emerged. Theme 1 (adaptation): pain is overwhelming and pain relief is a top priority, avoidance of pain-inducing factors, and resignation; theme 2 (emotional reactions to pain): feeling misunderstood, hopelessness, frustration, irritability, and concern for loved ones; theme 3 (functional limitations): daily life activities, social communication, and work; theme 4 (coping strategies): pharmacological therapies, behavioral strategies, social support strategies, and spiritual strategies.

Conclusions

This study provides a description of cancer patients' experiences related to the need for pain acceptance. These findings provide insight into the essential role of pain acceptance and underline the need to apply acceptance-based cognitive behavioral interventions as adjunctive non-pharmacological alternatives for chronic cancer pain.

Best-Evidence Rehabilitation for Chronic Pain Part 2: Pain during and after Cancer Treatment

Pain during, and especially after, cancer remains underestimated and undertreated. Moreover, both patients and health care providers are not aware of potential benefits of rehabilitation strategies for the management of pain during and following cancer treatment. In this paper, we firstly provided a state-of-the-art overview of the best evidence rehabilitation modalities for patients having (persistent) pain during and following cancer treatment, including educational interventions, specific exercise therapies, manual therapies, general exercise therapies and mind-body exercise therapies. Secondly, the findings were summarized from a clinical perspective and discussed from a scientific perspective. In conclusion, best evidence suggests that general exercise therapy has small pain-relieving effects. Supporting evidence for mind-body exercise therapy is available only in breast cancer patients. At this moment, there is a lack of high-quality evidence to support the use of specific exercises and manual therapy at the affected region for pain relief during and after cancer treatment. No clinically relevant results were found in favor of educational interventions restricted to a biomedical approach of pain. To increase available evidence these rehabilitation modalities should be applied according to, and within, a multidisciplinary biopsychosocial pain management approach. Larger, well-designed clinical trials tailored to the origin of pain and with proper evaluation of pain-related functioning and the patient’s pain experience are needed.

An in-hospital clinical care pathway with integrated decision support for cancer pain management reduced pain intensity and needs for hospital stay

PURPOSE

A clinical care pathway for pain management in a palliative care unit was studied with outcomes related to patients, physicians, and health care service. Mandatory use of patient-reported outcome measures (PROMs) and physician-directed decision support (DS) were integrated parts of the pathway.

METHODS

Adult cancer patients with pain intensity (PI) ≥ 5 (NRS 0-10) at admission were eligible. The patients reported average and worst PI at admission, day four, and discharge. The physicians completed the DS at admission and day four. The DS presented potential needs for treatment changes based on pain severity and pathophysiology. The physicians reported treatment changes due to input from the DS system. The two primary outcomes were average and worst PI changes from admission to discharge. Hospital length of stay (LOS) was registered.

RESULTS

Of 52 included patients, 41 were discharged alive. For those, the mean average PI at admission and at discharge was 5.8 and 2.4, respectively, a reduction of 3.4 points (CI 95% 2.7-4.1). The corresponding worst pain intensities were 7.9 and 3.8, a reduction of 4.1 points (CI 95% 3.4-4.8). The physicians completed DS forms for all patients. Fifty-five percent (CI 95% 41-69) of the patients had pain intervention changes based on the DS. A significant reduction in LOS (4.4 days, CI 95% 0.5-8.3) was observed during the study period.

CONCLUSIONS

The interventions were implemented according to the intentions and PI was reduced as hypothesized. For evaluation of generalizability, the interventions should be studied in other settings and with a controlled design.

Genetic Variants Associated with Cancer Pain and Response to Opioid Analgesics: Implications for Precision Pain Management

OBJECTIVE

To review the current knowledge on the association of genetic variants with cancer pain.

DATA SOURCES

Data-based publications and review articles retrieved from PubMed, CINAHL, and Web of Science, as well as an additional search in Google Scholar.

CONCLUSION

Genetic variability can influence differential pain perception and response to opioids in cancer patients, which will have implications in the optimal personalized treatment of cancer pain. More studies are warranted to replicate findings.

IMPLICATIONS FOR NURSING PRACTICE

Nurses are poised to educate patients on biomarker testing and interpretation and to use precision pain management strategies based on this information.

Pain Management in the Cancer Survivor

OBJECTIVES

To describe assessment and interdisciplinary management of pain in the cancer survivor over the continuum of cancer care.

DATA SOURCES

Review of the literature and treatment standards.

CONCLUSION

Pain remains a primary concern throughout the cancer trajectory across all age groups and diagnoses, emphasizing the need to integrate pain assessment and management across the continuum of cancer survivorship and across care settings. Types of pain, pain patterns, assessment of cancer pain in cancer survivors, current strategies and challenges for management, and effective communication and documentation of the process are described. Communication between and among health care clinicians in a way that effectively articulates the individual patient experience, including documentation in the electronic medical record, requires consistent workflows and terminology. The opioid crisis increases the urgency in effective strategies for interdisciplinary pain assessment and management.

IMPLICATIONS FOR NURSING PRACTICE

Oncology clinicians must be able to adequately assess pain, track pain over time, understand and implement a cadre of strategies to manage pain, and effectively pursue any suspicious pain patterns that may indicate recurrence or progression of cancer or other underlying etiologies. The oncology nurse is at the core of patient-clinician communication, critical to effectively describing pain as experienced by the individual patient and continues to play a key role in maintaining consistency of message that is necessary to manage pain over the continuum of cancer survivorship.

Protective Effects of Omega-3 Fatty Acids in Cancer-Related Complications

Omega-3 polyunsaturated fatty acids (PUFAs) are considered immunonutrients and are commonly used in the nutritional therapy of cancer patients due to their ample biological effects. Omega-3 PUFAs play essential roles in cell signaling and in the cell structure and fluidity of membranes. They participate in the resolution of inflammation and have anti-inflammatory and antinociceptive effects. Additionally, they can act as agonists of G protein-coupled receptors, namely, GPR40/FFA1 and GPR120/FFA4. Cancer patients undergo complications, such as anorexia-cachexia syndrome, pain, depression, and paraneoplastic syndromes. Interestingly, the 2017 European Society for Clinical Nutrition and Metabolism (ESPEN) guidelines for cancer patients only discuss the use of omega-3 PUFAs for cancer-cachexia treatment, leaving aside other cancer-related complications that could potentially be managed by omega-3 PUFA supplementation. This critical review aimed to discuss the effects and the possible underlying mechanisms of omega-3 PUFA supplementation in cancer-related complications. Data compilation in this critical review indicates that further investigation is still required to assess the factual benefits of omega-3 PUFA supplementation in cancer-associated illnesses. Nevertheless, preclinical evidence reveals that omega-3 PUFAs and their metabolites might modulate pivotal pathways underlying complications secondary to cancer, indicating that this is a promising field of knowledge to be explored.

Cancer Pain Assessment and Classification

More than half of patients affected by cancer experience pain of moderate-to-severe intensity, often in multiple sites, and of different etiologies and underlying mechanisms. The heterogeneity of pain mechanisms is expressed with the fluctuating nature of cancer pain intensity and clinical characteristics. Traditional ways of classifying pain in the cancer population include distinguishing pain etiology, clinical characteristics related to pain and the patient, pathophysiology, and the use of already validated classification systems. Concepts like breakthrough, nociceptive, neuropathic, and mixed pain are very important in the assessment of pain in this population of patients. When dealing with patients affected by cancer pain it is also very important to be familiar to the characteristics of specific pain syndromes that are usually encountered. In this article we review methods presently applied for classifying cancer pain highlighting the importance of an accurate clinical evaluation in providing adequate analgesia to patients.

Cancer-Related Neuropathic Pain

Neuropathic pain in cancer is common and debilitating. It is important to differentiate neuropathic pain from other cancer-related pains as it is associated with worse pain outcomes and requires different treatment strategies. This review summarises recent updates to pain classification, aetiology, pain assessment and current recommendations for treatment in patients with cancer-related neuropathic pain.

Standards for the management of cancer-related pain across Europe-A position paper from the EFIC Task Force on Cancer Pain

BACKGROUND AND OBJECTIVE

Pain is a common symptom in patients who survive cancer and in those who live with progressive advanced disease. Evidence from meta-analyses suggests that pain remains poorly controlled for a large proportion of patients; barriers to good management include poor assessment of pain, inadequate support for patient self-management and late or inadequate access to strong opioid analgesia in those with advanced disease.

METHODS

The European Pain Federation (EFIC) established a Task Force in 2017 which convened a European group of experts, drawn from a diverse range of relevant clinical disciplines, to prepare a position paper on appropriate standards for the management of cancer-related pain. The expert panel reviewed the available literature and made recommendations using the GRADE system to combine quality of evidence with strength of recommendation. The panel took into account the desirable and undesirable effects of the management recommendation, including the cost and inconvenience of each when deciding the recommendation.

RESULTS AND CONCLUSIONS

The 10 standards presented are aimed to improve cancer pain management and reduce variation in practice across Europe. The Task Force believes that adoption of these standards by all 37 countries will promote the quality of care of patients with cancer-related pain and reduce unnecessary suffering.

SIGNIFICANCE

Pain affects up to 40% of cancer survivors and affects at least 66% of patients with advanced progressive disease, many of whom experience poor pain control. These 10 standards are aimed to improve cancer pain management, promote the quality of care of patients and reduce variation across Europe.

The IASP classification of chronic pain for ICD-11: chronic neuropathic pain

The upcoming 11th revision of the International Statistical Classification of Diseases and Related Health Problems (ICD) of the World Health Organization (WHO) offers a unique opportunity to improve the representation of painful disorders. For this purpose, the International Association for the Study of Pain (IASP) has convened an interdisciplinary task force of pain specialists. Here, we present the case for a reclassification of nervous system lesions or diseases associated with persistent or recurrent pain for ≥3 months. The new classification lists the most common conditions of peripheral neuropathic pain: trigeminal neuralgia, peripheral nerve injury, painful polyneuropathy, postherpetic neuralgia, and painful radiculopathy. Conditions of central neuropathic pain include pain caused by spinal cord or brain injury, poststroke pain, and pain associated with multiple sclerosis. Diseases not explicitly mentioned in the classification are captured in residual categories of ICD-11. Conditions of chronic neuropathic pain are either insufficiently defined or missing in the current version of the ICD, despite their prevalence and clinical importance. We provide the short definitions of diagnostic entities for which we submitted more detailed content models to the WHO. Definitions and content models were established in collaboration with the Classification Committee of the IASP's Neuropathic Pain Special Interest Group (NeuPSIG). Up to 10% of the general population experience neuropathic pain. The majority of these patients do not receive satisfactory relief with existing treatments. A precise classification of chronic neuropathic pain in ICD-11 is necessary to document this public health need and the therapeutic challenges related to chronic neuropathic pain.

Pilot field testing of the chronic pain classification for ICD-11: the results of ecological coding

BACKGROUND

A task force of the International Association for the Study of Pain (IASP) has developed a classification of chronic pain for the ICD-11 consisting of seven major categories. The objective was to test whether the proposed categories were exhaustive and mutually exclusive. In addition, the perceived utility of the diagnoses and the raters' subjective diagnostic certainty were to be assessed.

METHODS

Five independent pain centers in three continents coded 507 consecutive patients. The raters received the definitions for the main diagnostic categories of the proposed classification and were asked to allocate diagnostic categories to each patient. In addition, they were asked to indicate how useful they judged the diagnosis to be from 0 (not at all) to 3 (completely) and how confident they were in their category allocation.

RESULTS

The two largest groups of patients were coded as either chronic primary pain or chronic secondary musculoskeletal pain. Of the 507 patients coded, 3.0% had chronic pain not fitting any of the proposed categories (97% exhaustiveness), 20.1% received more than one diagnosis. After adjusting for double coding due to technical reasons, 2.0% of cases remained (98% uniqueness). The mean perceived utility was 1.9 ± 1.0, the mean diagnostic confidence was 2.0 ± 1.0.

CONCLUSIONS

The categories proved exhaustive with few cases being classified as unspecified chronic pain, and they showed themselves to be mutually exclusive. The categories were regarded as useful with particularly high ratings for the newly introduced categories (chronic cancer-related pain among others). The confidence in allocating the diagnoses was good although no training regarding the ICD-11 categories had been possible at this stage of the development.