Absolute and relative reliability of a comprehensive quantitative sensory testing protocol in women treated for breast cancer

Increased TRPA1 functionality in the skin of rats and cancer patients following oxaliplatin treatment

Chemotherapy-induced peripheral neuropathy is a debilitating pathology affecting a majority of patients who are being treated with specific cytostatic compounds including oxaliplatin. Various in vitro, ex vivo and in vivo preclinical experiments indicate that transient receptor potential ankyrin 1 (TRPA1) plays a crucial role in the symptomatology of chemotherapy-induced peripheral neuropathy. However, it is unclear whether oxaliplatin also modulates the TRPA1 functionality in the skin of rodents or patients. Here, we quantified the vasodilation after topical application of the TRPA1 agonist cinnamaldehyde in a rodent model of chemotherapy-induced peripheral neuropathy (male Sprague Dawley rats, aged 6 weeks) as well as on fingers of patients suffering from chronic chemotherapy-induced peripheral neuropathy after oxaliplatin treatment. Compared to vehicle-treated rats, a cumulative dose of oxaliplatin 32 mg/kg enhanced the vasodilation after cinnamaldehyde application on rat abdominal skin. Likewise, also in patients with chronic chemotherapy-induced peripheral neuropathy after oxaliplatin, the response to cinnamaldehyde was significantly higher compared to sex- and age-matched healthy controls. Thereby, this study is the first to translate the evidence of increased TRPA1 functionality in vitro or ex vivo in rodents to in vivo conditions in human. The increased TRPA1 functionality in patients with chronic chemotherapy-induced peripheral neuropathy does not only confirm the potential of TRPA1 as target to hit to provide efficacious analgesia, it also paves the way for additional patient stratification on a molecular level and possible treatment response prediction. PERSPECTIVE: The cinnamaldehyde-induced, TRPA1-mediated vasodilation was enhanced in patients with oxaliplatin-induced peripheral neuropathy versus healthy controls, confirming the potential of TRPA1 as target-to-hit for this indication.

From breast cancer diagnosis to survivorship: Analyzing perioperative biopsychosocial phenotypes and their relationship to pain on long term

Persistent breast cancer treatment-related pain affects up to 40% of patients, decreasing their quality of life (QoL). While current research typically utilizes correlation and regression analysis to identify biopsychosocial phenotypes contributing to this pain, this study employs cluster analysis to identify qualitatively different phenotypes based on somatosensory and psychosocial characteristics both before and one week post-breast cancer surgery. Further, it investigates how these phenotypes are related to pain intensity one year post-surgery and examines the evolution of phenotype membership from pre- to post-surgery. Somatosensory and psychosocial functioning was evaluated pre- and post-surgery in 184 women undergoing unilateral breast cancer surgery. Eight different quantitative sensory testing (QST) methods including mechanical detection and pain thresholds, pressure pain thresholds, thermal detection and pain thresholds, and conditioned pain modulation were performed at the surgical area (trunk, arm, major pectoral muscle) and a distant location (quadriceps muscle). Psychosocial functioning was assessed using the Central Sensitization Inventory, Pain Catastrophizing Scale, Depression Anxiety Stress Scale-21, and the McGill Quality of Life Questionnaire. Pain intensity was evaluated one year post-breast cancer surgery using the Visual Analogue Scale. Latent class analysis identified five distinct phenotypes before and post-surgery, characterized by differences in mechanical and pain thresholds alongside psychosocial factors. Moreover, higher psychosocial distress and lower QoL correlated with elevated pain intensity one year post-surgery. These findings underscore the importance of addressing breast cancer patients' mental health perioperatively. Therefore, future research should explore whether psychological interventions perioperatively can reduce long-term pain intensity. PERSPECTIVE: This secondary analysis, utilizing cluster analysis, reveals five distinct phenotype based on somatosensory and psychosocial characteristics both before and post-breast cancer surgery. Higher psychosocial distress and lower quality of life correlated with elevated pain intensity one year post-surgery, emphasizing the need to address patients' mental health perioperatively. TRIAL REGISTRATION: clinicaltrials.gov (NCT03351075).

Preoperative glycaemic control, number of pain locations, structural knee damage, self-reported central sensitisation, satisfaction and personal control are predictive of 1-year postoperative pain, and change in pain from pre- to 1-year posttotal knee arthroplasty

PURPOSE

The aim of this study was to identify preoperative predictors for 1-year posttotal knee arthroplasty (TKA) pain and pre- to post-TKA pain difference in knee osteoarthritis (KOA) patients.

METHODS

From March 2018 to July 2023, this prospective longitudinal cohort study enrolled KOA patients awaiting TKA from four hospitals in Belgium and the Netherlands. Different biopsychosocial predictors were assessed preoperatively by questionnaires and physical examinations (input variables). The Knee injury and Osteoarthritis Outcome Score (KOOS) subscale pain was used to measure pain intensity. The absolute KOOS subscale pain score 1-year post-TKA and the difference score (ΔKOOS = 1-year postoperative - preoperative) were used as primary outcome measures (output variables). Two multivariable linear regression analyses were performed.

RESULTS

Two hundred and twenty-three participants were included after multiple imputation. Worse absolute KOOS subscale pain scores 1-year post-TKA and negative or closer to zero ΔKOOS subscale pain scores were predicted by self-reported central sensitisation, lower KOA grade and preoperative satisfaction, and higher glycated haemoglobin, number of pain locations and personal control (adjusted R2 = 0.25). Additional predictors of negative or closer to zero ΔKOOS subscale pain scores were being self-employed, higher preoperative pain and function (adjusted R2 = 0.37).

CONCLUSION

This study reports different biopsychosocial predictors for both outcomes that have filtered out other potential predictors and provide value for future studies on developing risk assessment tools for the prediction of chronic TKA pain.

PROTOCOL REGISTRATION

The protocol is registered at clinicaltrials.gov (NCT05380648) on 13 May 2022.

LEVEL OF EVIDENCE

Level II.

Test-retest and interrater reliability of experimental within-subject variability of pain reports as assessed by the focused analgesia selection test

Introduction

Within-subject variability (WSV) of pain intensity reports has been shown to predict the placebo response. The focused analgesia selection test (FAST), which allows to experimentally assess WSV of pain reports, has been used as a screening tool to identify participants who are likely to have a strong placebo response in drug-development clinical trials. Yet, the reliability of FAST has not been reported.

Objectives

To assess test-retest and interrater reliability of the FAST outcomes. To mimic pharma-sponsored clinical trials, we enlisted inexperienced assessors who underwent limited training.

Methods

Healthy volunteers performed the FAST twice within a week and were randomly assigned to either the test-retest group or the interrater group. T-tests, partial Pearson correlations, intraclass correlations (ICC), and Bland-Altman plots were generated to assess FAST outcomes' reliability.

Results

Sixty-three participants completed the study and were assigned to the test-retest (N = 33) or interrater (N = 30) arms. No statistically significant differences in the FAST outcomes were detected between the 2 sessions, except for the FAST covariance (FAST CoV) in the interrater assessment (P = 0.009). Test-retest reliabilities of the FAST-main outcomes were r = 0.461, ICC = 0.385 for the FAST R 2 and r = 0.605, ICC = 0.539 for the FAST ICC and in the interrater cohort, they were FAST R 2: r = 0.321, ICC = 0.337 and FAST ICC: r = 0.355, ICC = 0.330.

Conclusion

Using inexperienced assessors, the FAST outcomes test-retest ranged from moderate to strong, whereas the interrater reliability ranged from weak to poor. These results highlight the importance of adequately training study staff members before using this tool in multicentre clinical trials.

Application of the IASP Grading System to Identify Underlying Pain Mechanisms in Patients With Knee Osteoarthritis: A Prospective Cohort Study

OBJECTIVES

This study aimed to apply the International Association for the Study of Pain (IASP) grading system for identifying nociplastic pain in knee osteoarthritis (KOA) awaiting total knee arthroplasty (TKA) and propose criteria to fine-tune decision-making. In addition, the study aimed to characterize a "probable" versus "no or possible" nociplastic pain mechanism using biopsychosocial variables and compare both groups in their 1-year post-TKA response.

METHODS

A secondary analysis of baseline data of a longitudinal prospective study involving 197 patients with KOA awaiting total TKA in Belgium and the Netherlands was performed. Two approaches, one considering 4 and the other 3 pain locations (step 2 of the grading system), were presented. Linear mixed model analyses were performed to compare the probable and no or possible nociplastic pain mechanism groups for several preoperative biopsychosocial-related variables and 1-year postoperative pain. Also, a sensitivity analysis, comparing 3 pain mechanism groups, was performed.

RESULTS

Thirty (15.22%-approach 4 pain locations) and 46 (23.35%-approach 3 pain locations) participants were categorized under probable nociplastic pain. Irrespective of the pain location approach or sensitivity analysis, the probable nociplastic pain group included more woman, was younger, exhibited worse results on various preoperative pain-related and psychological variables, and had more pain 1-year post-TKA compared with the other group.

DISCUSSION

This study proposed additional criteria to fine-tune the grading system for nociplastic pain (except for discrete/regional/multifocal/widespread pain) and characterized a subgroup of patients with KOA with probable nociplastic pain. Future research is warranted for further validation.

Continuum of somatosensory profiles in breast cancer survivors with and without pain, compared to healthy controls and patients with fibromyalgia

CONTEXT

The prevalence of persistent pain among breast cancer survivors (BCS) is high, and it is unclear what distinguishes those with persistent pain from those without. Research suggests that differences in somatosensory function evaluated by quantitative sensory testing (QST) may be responsible.

OBJECTIVES

This study aimed to describe somatosensory profiles in terms of hyper- and hypoesthesia in BCS with and without persistent pain using reference data from healthy controls. Second, QST parameters of BCS with and without pain were compared with those of healthy controls (i.e., a negative control group) and patients with fibromyalgia (i.e., a positive control group).

METHODS

Participants (n = 128) were divided into four equal groups: healthy controls, BCS with persistent pain, BCS without persistent pain, and patients with fibromyalgia. Nine QST parameters were evaluated at the trunk and at a remote location. Somatosensory profiles were determined by Z-score transformation of QST data using normative data from healthy controls.

RESULTS

At the trunk, compared to healthy controls, BCS with persistent pain exhibited sensory aberrations across five out of seven QST parameters: pressure pain threshold, mechanical detection, and thermal thresholds. Pain-free BCS showed similar sensory aberrations across the four QST parameters compared to healthy controls: mechanical detection and thermal thresholds. Temporal summation and conditioned pain modulation were not significantly different between groups.

CONCLUSION

BCS with persistent pain exert aberrations in peripheral processing of nociceptive signals, heightened facilitation of nociceptive signals, and higher psychosocial burden when compared to pain-free BCS, healthy controls, and patients with fibromyalgia.

SIGNIFICANCE

This study investigates the somatosensory function of breast cancer survivors with and without persistent pain using quantitative sensory testing and two control group (i.e., patients with fibromyalgia and healthy controls). Our results indicate somatosensory aberrations within the peripheral, but not central pathways in breast cancer survivors with persistent pain. Our findings contribute to a better understanding of the somatosensory mechanisms underlying persistent pain, which may inform future interventions to prevent the development of persistent pain, and improve treatment modalities.

Unravelling relationships between obesity, diabetes, and factors related to somatosensory functioning in knee osteoarthritis patients

OBJECTIVE

This study explores the association between obesity, diabetes, and somatosensory functioning in patients with knee osteoarthritis (OA), aiming to understand how metabolic conditions are related to pain mechanisms in this patient population. We hypothesized that higher body mass index (BMI), fat mass, and glycated hemoglobin levels (HbA1c) are associated with signs of altered somatosensory functioning.

METHODS

A cross-sectional analysis was conducted as part of a larger multicentre prospective cohort study. Data were collected from patients awaiting total knee arthroplasty in Belgium and the Netherlands. Associations between BMI, fat mass, HbA1c, and various pain-related variables were examined employing Pearson and Spearman correlation analyses which were further analyzed with linear regression techniques.

RESULTS

The study included 223 participants. Analysis revealed a significant although weak negative correlation between fat mass and pressure pain thresholds (PPT) at multiple locations, suggesting a link between higher fat mass and increased mechanical hyperalgesia. There were no significant correlations between BMI and pain-related outcomes. HbA1c levels showed very weak positive correlations with pain measures but did not withstand correction for multiple testing.

CONCLUSION

The findings indicate that fat mass may be closely associated with altered somatosensory functioning in patients with knee OA. However, no significant correlations were found between BMI or HbA1c levels and pain-related outcomes. Future research should focus on longitudinal studies to elucidate the causal relationships and further explore the impact of metabolic factors on pain mechanisms in this patient population. Key Points • The findings indicate that fat mass may be closely associated with altered somatosensory functioning in patients with knee OA.

Does pain intensity after total knee arthroplasty depend on somatosensory functioning in knee osteoarthritis patients? A prospective cohort study

The objective of this study is to determine whether the change in pain intensity over time differs between somatosensory functioning evolution profiles in knee osteoarthritis (KOA) patients undergoing total knee arthroplasty (TKA). This longitudinal prospective cohort study, conducted between March 2018 and July 2023, included KOA patients undergoing TKA in four hospitals in Belgium and the Netherlands. The evolution of the Knee Injury and Osteoarthritis Outcome Score (KOOS) subscale pain over time (baseline, 3 months, and 1 year post-TKA scores) was the outcome variable. The evolution scores of quantitative sensory testing (QST) and Central Sensitization Inventory (CSI) over time (baseline and 1 year post-TKA scores) were used to make subgroups. Participants were divided into separate normal, recovered, and persistent disturbed somatosensory subgroups based on the CSI, local and widespread pressure pain threshold [PPT] and heat allodynia, temporal summation [TS], and conditioned pain modulation [CPM]. Linear mixed model analyses were performed. Two hundred twenty-three participants were included. The persistent disturbed somatosensory functioning group had less pronounced pain improvement (based on CSI and local heat allodynia) and worse pain scores 1 year post-TKA (based on CSI, local PPT and heat allodynia, and TS) compared to the normal somatosensory functioning group. This persistent group also had worse pain scores 1 year post-TKA compared to the recovered group (based on CSI). The study suggests the presence of a "centrally driven central sensitization" subgroup in KOA patients awaiting TKA in four of seven grouping variables, comprising their less pain improvement or worse pain score after TKA. Future research should validate these findings further. The protocol is registered at clinicaltrials.gov (NCT05380648).

Restoration of normal central pain processing following manual therapy in nonspecific chronic neck pain

OBJECTIVE

To determine if a 4-week manual therapy treatment restores normal functioning of central pain processing mechanisms in non-specific chronic neck pain (NSCNP), as well as the existence of a possible relationship between changes in pain processing mechanisms and clinical outcome.

DESIGN

Cohort study.

METHODS

Sixty-three patients with NSCNP, comprising 79% female, with a mean age of 45.8 years (standard deviation: 14.3), received four treatment sessions (once a week) of manual therapy including articular passive mobilizations, soft tissue mobilization and trigger point treatment. Pressure pain thresholds (PPTs), conditioned pain modulation (CPM) and temporal summation of pain (TSP) were evaluated at baseline and after treatment completion. Therapy outcome was measured using the Global Rating of Change Scale (GROC), the Neck disability Index (NDI), intensity of pain during the last 24 hours, Tampa Scale of Kinesiophobia (TSK) and Pain Catastrophizing Scale (PCS). Two sets of generalized linear mixed models with Gaussian response and the identity link were employed to evaluate the effect of the intervention on clinical, psychological and psychophysical measures and the association between psychophysical and clinical outcomes.

RESULTS

Following treatment, an increased CPM response (Coefficient: 0.89; 95% credibility interval = 0.14 to 1.65; P = .99) and attenuated TSP (Coefficient: -0.63; 95% credibility interval = -0.82 to -0.43; P = 1.00) were found, along with amelioration of pain and improved clinical status. PPTs at trapezius muscle on the side of neck pain were increased after therapy (Coefficient: 0.22; 95% credibility interval = 0.03 to 0.42; P = .98), but not those on the contralateral trapezius and tibialis anterior muscles. Only minor associations were found between normalization of TSP/CPM and measures of clinical outcome.

CONCLUSION

Clinical improvement after manual therapy is accompanied by restoration of CPM and TSP responses to normal levels in NSCNP patients. The existence of only minor associations between changes in central pain processing and clinical outcome suggests multiple mechanisms of action of manual therapy in NSCNP.

Prognostic factors for the development of upper limb dysfunctions after breast cancer: the UPLIFT-BC prospective longitudinal cohort study protocol

INTRODUCTION

Upper limb (UL) dysfunctions are highly prevalent in people after breast cancer and have a great impact on performing activities in daily living. To improve care, a more comprehensive understanding of the development and persistence of UL dysfunctions is needed. Therefore, the UPLIFT-BC study will primarily examine the prognostic value of different factors at the body functions and structures, environmental and personal level of the International Classification of Functioning, Disability and Health (ICF) framework at 1-month post-surgery for persisting UL dysfunctions at 6 months after finishing cancer treatment.

METHODS AND ANALYSIS

A prospective longitudinal cohort study, running from 1-week pre-surgery to 6 months post-local cancer treatment, is performed in a cohort of 250 women diagnosed with primary breast cancer. Different potentially prognostic factors to UL dysfunctions, covering body functions and structures, environmental and personal factors of the ICF, are assessed pre-surgically and at different time points post-surgery. The primary aim is to investigate the prognostic value of these factors at 1-month post-surgery for subjective UL function (ie, QuickDASH) at 6 months post-cancer treatment, that is, 6 months post-radiotherapy or post-surgery (T3), depending on the individuals' cancer treatment trajectory. In this, factors with relevant prognostic value pre-surgery are considered as well. Similar analyses are performed with an objective measure for UL function (ie, accelerometry) and a composite score of the combination of subjective and objective UL function. Second, in the subgroup of participants who receive radiotherapy, the prognostic value of the same factors is explored at 1-month post-radiotherapy and 6 months post-surgery. A forward stepwise selection strategy is used to obtain these multivariable prognostic models.

ETHICS AND DISSEMINATION

The study protocol was approved by the Ethics Committee of UZ/KU Leuven (reference number s66248). The results of this study will be published in peer-reviewed journals and will be presented at several research conferences.

TRIAL REGISTRATION NUMBER

NCT05297591.

Effectiveness of pain neuroscience education on somatosensory functioning after surgery for breast cancer: A double-blinded randomized controlled trial

Pain is one of the most prevalent and long-term adverse effects described by people who have undergone breast cancer surgery. Non-helpful perceptions and thoughts about pain may contribute to the transition of acute to persistent pain. Adding educational interventions to the current physical therapy program in this population may help to improve or prevent persistent pain. Pain neuroscience education (PNE) is a type of educational intervention that addresses the experience of pain in a broader sense by explaining pain not only from a biomedical perspective, but also from a psychological and social perspective. A double-blinded randomized controlled trial (EduCan trial) investigated whether PNE, in addition to a standard physiotherapy program immediately after surgery for breast cancer, was more effective on somatosensory functioning in the short (4 months postoperatively) and long term (18 months postoperatively), than providing a biomedical explanation for pain. Somatosensory functioning was evaluated using a self-reported questionnaire as well as a comprehensive quantitative sensory testing evaluation. The findings of this study revealed that adding six sessions of PNE to a standard physical therapy program (n = 184) did not result in a significantly different course of somatosensory functioning up to 18 months postoperatively as compared to biomedical pain education. These findings provide an interesting basis for future research into who should receive PNE after surgery for breast cancer (e.g., patient profiling or phenotyping) and how we can tailor it to the individual to increase its effectiveness.

Concurrent validity of dynamic bedside quantitative sensory testing paradigms in breast cancer survivors with persistent pain

BACKGROUND

Studies on the concurrent validity of clinically applicable testing protocols for conditioned pain modulation (CPM) and temporal summation of pain (TSP) in breast cancer survivors (BCS) with persistent pain are lacking.

OBJECTIVES

This study investigated the concurrent validity of two bedside protocols for CPM and TSP in comparison to a respective reference protocol. The participants' preferences for bedside CPM and TSP protocols were assessed.

METHODS

Thirty BCS experiencing persistent pain were included in this study. Each participant underwent a reference test along with two bedside alternatives for assessing both TSP and CPM. For CPM, a cold pressor test (CPT) and blood pressure cuff (BPC) were used as conditioning stimulus. The test stimulus was elicited in parallel by pressure pain threshold after 45 and 90 s of conditioning at the lower limb. The CPM reference test consisted of parallel heat stimuli at the forearms using a two-thermode system. TSP was elicited using a von Frey monofilament (256 mN) and an algometer (98 kPa) at the affected site and opposite lower limb. The TSP reference test consisted of heat stimuli at the affected site and opposite lower limb. Participants' testing preference was examined using a purpose-designed questionnaire. Spearman's rank test examined the correlation between protocols.

RESULTS

The two bedside CPM protocols were strongly correlated (r = 0.787-0.939, p < 0.005). A strong correlation was found between the BPC protocol and reference test using the relative effect magnitude (r = 0.541-0.555, p < 0.005). The bedside TSP protocols were moderately correlated with each other only at the lower limb using absolute change scores (r = 0.455, p = 0.012). No significant correlation was found between the bedside and reference TSP protocols.

CONCLUSION

The significantly moderate to very strong correlations between the bedside protocols validate their interchangeability. Researchers and clinicians should be able to choose which bedside protocol they utilize; however, participants favored the use of a BPC and algometer for the evaluation of CPM and TSP, respectively.

The Classification of Suspected Predominant Nociplastic Pain in People with Moderate and Severe Haemophilia: A Secondary Exploratory Study

In people with haemophilia (PwH), joint pain is a major comorbidity that is often overlooked and under-treated. It is believed that, to ensure the most successful outcome, pain management should be tailored to the predominant pain phenotype (i.e., nociceptive, neuropathic and nociplastic). The 2021 clinical criteria and grading system for nociplastic pain, established by the International Association for the Study of Pain (IASP), emphasize the necessity of early-stage identification and predominant pain type classification. Consistent with findings in other chronic musculoskeletal pain conditions, studies suggest that a subgroup of PwH suffers from nociplastic pain, i.e., pain arising from altered nociception rather than structural damage, but this has not yet been explored in PwH. This study aimed to identify PwH with "unlikely", "possible" and "probable" nociplastic pain and investigate differences in anthropometric, demographic and clinical characteristics and psychological factors between subgroups of PwH and healthy individuals.: The IASP clinical criteria and grading system were used to classify pain types in adult men with moderate or severe haemophilia recruited from two Belgian haemophilia treatment centres. Statistical analyses were applied to study between-subgroup differences. Of 94 PwH, 80 PwH (85%) were classified with "unlikely" and 14 (15%) with "at least possible" nociplastic pain (including 5 PwH (5%) with "possible" and 9 PwH (10%) with "probable" nociplastic pain). PwH in both the "unlikely" and "at least possible" nociplastic pain groups showed significantly higher levels of unhelpful psychological factors compared to healthy individuals. Additionally, age may partially account for the observed differences in body height and psychological factors. Larger sample sizes may be needed to detect more subtle between-group differences. study confirmed the presence of nociplastic pain in haemophilia, categorising a notable subgroup as individuals who experience at least possible nociplastic pain. These exploratory insights may provide a starting point for future studies and the development of more effective and tailored pain management.

Psychophysical assessment of pain in adults with moderate and severe haemophilia: A cross-sectional study

BACKGROUND

Joint pain is the hallmark of haemophilia; therefore it seems clinically rather a musculoskeletal than a bleeding disorder. Although joint pain in people with haemophilia (PwH) is a complex and multidimensional problem, pain assessment remains primarily focused on the structural evaluation of their joints. Whereas, only few data are available on the potential implication of psychophysical and psychological factors.

OBJECTIVE

This study aimed to perform a psychophysical pain assessment including quantitative sensory testing (QST) and an evaluation of psychological factors in a large sample of PwH, to get insight into the individuals' pain system.

METHODS

Ninety-nine adults (36.9 ± 13.5 years) with moderate/severe haemophilia A/B and 46 healthy controls filled in self-reported pain and psychological questionnaires and underwent a QST evaluation including static and dynamic tests. Static tests focused on the determination of thermal detection and pain thresholds and mechanical pressure pain thresholds. Dynamic tests evaluated pain facilitation and the efficacy of endogenous pain inhibition. Besides comparing PwH and healthy controls, between-subgroup differences were studied in PwH based on their pain distribution.

RESULTS

The study revealed increased thermal and mechanical pain sensitivity and the presence of unhelpful psychological factors such as anxiety/depression in PwH. Among the subgroups, especially PwH with widespread pain showed altered somatosensory functioning. Enhanced pain facilitation and impaired efficacy of endogenous pain inhibition in PwH could not be observed.

CONCLUSION

Altered somatosensory functioning and unhelpful psychological factors, appear to play an important role in the pathophysiology of pain in PwH, especially in PwH with widespread pain.

Widespread distribution and altered pain processing in head and neck cancer survivors at long-term after treatment

PURPOSE

Radiotherapy (RT) treatment in head and neck cancer (HNC) patients may induce long-term sequels as pain, which nowadays is not fully understand. Therefore, there is a need of characterization of pain features in HNC to enhance after oncology treatment management. Head and neck cancer survivors develop chronic pain after radiotherapy treatment. The purpose of the current study is to evaluate the presence of pain, pain distribution, and pain processing by means of patient reported outcomes and quantitative sensory testing.

METHODS

Pain pressure threshold (PPT), temporal summation (TS), Brief Pain Inventory (BPI), Widespread Pain Index (WPI), The Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire, and EuroQol5D5L were assessed in 20 head and neck cancer survivors (sHNC) and 20 health-related sex and age-matched controls.

RESULTS

The sHNC present lower PPT values in both the affected and non-affected side than did the healthy controls, especially in the widespread pain in the body, an altered TS in both affected and non-affected side and lower scores in quality of life and arm dysfunction.

CONCLUSIONS

Following radiotherapy treatment after 1 year, sHNC present widespread pain, hypersensitivity in the radiated area, altered pain processing, upper limb affection, and a QoL diminution. These data provide evidence that a peripheral and central sensitization is happening in sHNC. Future efforts should focus on preventing pain after oncologic treatment. The comprehension about pain and its features in sHNC enhance health professional understanding and allows to tailor an optimal patient-targeted pain treatment.

Predictors of persistent post-surgical pain intensity and interference at 1 year after breast cancer surgery: assessing central sensitization, central sensitivity symptoms, and psychological factors

BACKGROUND

Persistent post-surgical pain (PPSP) is associated with upper limb dysfunction and decreased quality of life and causes long-term suffering for breast cancer survivors after surgery. However, the predictors of PPSP remain unclear. The purpose of this study was to examine predictors of PPSP intensity and interference at 1 year postoperatively, focusing on treatment-related factors, pre- and postoperative central sensitization (CS), CS-related symptoms (e.g., muscle stiffness, fatigue, sleep disturbances), and psychological factors.

METHODS

Eighty-eight women with planned unilateral breast cancer surgery were included in this longitudinal study. CS, CS-related symptoms, and psychological factors were assessed preoperatively, 1 month postoperatively, and 1 year postoperatively. Analysis of covariance was used to compare the groups with and without PPSP, accounting for treatment-related factors. Multiple regression analysis was performed to identify predictors of PPSP intensity and interference at 1 year postoperatively.

RESULTS

Even after adjusting for covariates, preoperative and 1-month postoperative Central Sensitization Inventory scores in the PPSP group were significantly higher than scores in the group without PPSP. Multiple regression analysis showed that axillary lymph node dissection (ALND) and 1-month postoperative CS-related symptoms were independent predictors of PPSP intensity and interference at 1 year postoperatively (p < 0.01).

CONCLUSION

We found that ALND and 1-month postoperative CS-related symptoms were predictors of PPSP intensity and interference at 1 year postoperatively.

Factors Associated with Low Inter-Session Reliability of Conditioned Pain Modulation in Older People with or Without Chronic Musculoskeletal Pain

Purpose

Conditioned pain modulation (CPM) is a measurement of the descending pain pathways that inhibit or facilitate afferent noxious stimuli. The reliability of CPM in older individuals with or without chronic musculoskeletal pain has not been sufficiently reported. This study aimed to examine the inter-session reliability of CPM in these cohorts and the factors in CPM reliability.

Patients and Methods

Individuals aged 65 or older were recruited in Narita, Japan. The measurements were performed on separate days 2 weeks apart (sessions 1 and 2). Each participant's hand was immersed in cold water, and we measured pressure pain threshold (PPT) before and after the immersion. The ratio before and after PPT measurements was presented as CPM index. The autonomic activities (heart rate variability, heart rate, and blood pressure) were simultaneously measured. An absolute reliability of CPM index was analyzed by the adjusted two-way analysis of variance (ANOVA) and the Bland Altman plot, and relative reliability was analyzed by intraclass correlation coefficient (ICC). Spearman's rho correlation and the adjusted multivariate regression analysis were utilized for examining the CPM reliability factors.

Results

Thirty-two participants were divided into two groups: chronic pain (n=19) and non-chronic pain (n=13) groups. The mean difference between session 1 and 2 in CPM index showed a systematic error in the chronic pain group at 17.3 (confidence interval, CI: 15.0 to 19.7), but none in the non-chronic pain group at 3.7 (CI: -0.02 to 7.4). The adjusted two-way ANOVA for CPM index did not identify any differences. ICC was not significant at p=-0.247 in the non-chronic and 0.167 in chronic pain. Multivariate regression analysis revealed total power and low/high frequencies as significant factors for CPM index.

Conclusion

This study identified low inter-session reliability in older adults with chronic musculoskeletal pain and autonomic nervous system activities as factors in CPM reliability.

Biopsychosocial risk factors for pain and pain-related disability 1 year after surgery for breast cancer

PURPOSE

Knowledge regarding risk factors for pain in the long term after surgery for breast cancer may be of great value in preventing this prevalent and debilitating side effect. Despite the biopsychosocial nature of pain, the predictive value of both pre- and postoperative biopsychosocial functioning for long-term pain intensity and pain-related disability has not yet been studied.

METHODS

One hundred sixty-six women planned for unilateral breast cancer surgery were included in this prospective cohort study. Pre- and postoperative outcomes related to pain, psychosocial, and somatosensory functioning (questionnaires and quantitative sensory testing) were evaluated as risk factors for pain intensity (visual analog scale) and pain-related disability (pain disability index) 1 year after surgery for breast cancer. Both bivariable and stepwise linear regression analyses were performed.

RESULTS

The most consistent biopsychosocial risk factors were symptoms related to altered central somatosensory functioning (central sensitization inventory), psychological symptoms, and social support (psychological symptoms and support subscale of McGill Quality of Life Questionnaire). Results also showed that a pre- and postoperative disturbed functioning of the somatosensory nervous system in the surgical area could provide additional information regarding pain intensity or pain-related disability in the long term after surgery for breast cancer.

CONCLUSION

This study revealed several biopsychosocial characteristics that might be used to identify women more vulnerable to have pain and pain-related disability in the long term after surgery for breast cancer, allowing for more effective pain management and prevention.