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

Preoperative pain sensitivity and its correlation with postoperative acute and chronic pain: a systematic review and meta-analysis

BACKGROUND

Preoperative pain sensitivity (PPS) can be associated with postsurgical pain. However, estimates of this association are scarce. Confirming this correlation is essential to identifying patients at high risk for severe postoperative pain and for developing analgesic strategy. This systematic review and meta-analysis summarises PPS and assessed its correlation with postoperative pain.

METHODS

PubMed, Scopus, Cochrane Library, and PsycINFO were searched up to October 1, 2023, for studies reporting the association between PPS and postsurgical pain. Two authors abstracted estimates of the effect of each method independently. A random-effects model was used to combine data. Subgroup analyses were performed to investigate the effect of pain types and surgical procedures on outcomes.

RESULTS

A total of 70 prospective observational studies were included. A meta-analysis of 50 studies was performed. Postoperative pain was negatively associated with pressure pain threshold (PPT; r=-0.15, 95% confidence interval [CI] -0.23 to -0.07]) and electrical pain threshold (EPT; r=-0.28, 95% CI -0.42 to -0.14), but positively correlated with temporal summation of pain (TSP; r=0.21, 95% CI 0.12-0.30) and Pain Sensitivity Questionnaire (PSQ; r=0.25, 95% CI 0.13-0.37). Subgroup analysis showed that only TSP was associated with acute and chronic postoperative pain, whereas PPT, EPT, and PSQ were only associated with acute pain. A multilevel (three-level) meta-analysis showed that PSQ was not associated with postoperative pain.

CONCLUSIONS

Lower PPT and EPT, and higher TSP are associated with acute postoperative pain while only TSP is associated with chronic postoperative pain. Patients with abnormal preoperative pain sensitivity should be identified by clinicians to adopt early interventions for effective analgesia.

SYSTEMATIC REVIEW PROTOCOL

PROSPERO (CRD42023465727).

Association of Aromatase Inhibitor-Induced Musculoskeletal Symptoms with Central Sensitization-Related Symptoms: A Cross-Sectional Study

Introduction

Aromatase inhibitor (AI)-induced musculoskeletal symptoms (AIMSS) can decrease health-related quality of life and lead to discontinuation of AI therapy for postmenopausal women with breast cancer (BC). Although central sensitization (CS) may contribute to AIMSS, the relevance of CS-related symptoms to AIMSS has not been fully clarified. This study aimed to investigate the relationship between AIMSS and CS-related symptoms in women with BC who received AI therapy.

Methods

This cross-sectional study recruited women who underwent BC surgery before at least 1 year and were taking AI for at least 6 months. Participants were assessed for joint pain and CS-related symptoms using the central sensitization inventory (CSI). The severity of CS-related symptoms was classified into three groups, and the prevalence of AIMSS was calculated. Multiple logistic regression analysis was used to assess the relationship between AIMSS and factors of possible relevance to AIMSS, including CSI severity.

Results

Of the 73 women who were included in this study, 31 (42.4%) were categorized into the AIMSS group and 42 (57.6%) into the non-AIMSS group. Participants with a history of chemotherapy and higher CSI score were significantly more likely to have AIMSS. Multiple logistic regression analysis showed that a history of chemotherapy (odds ratio = 4.21) and higher CSI severity (odds ratio = 13.43) had significantly associated with AIMSS.

Conclusion

CS-related symptoms assessed using CSI may be strongly associated with AIMSS. Further longitudinal studies to investigate the causal relationship and effectiveness of CS-targeted interventions are needed to prevent and treat AIMSS effectively.

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.

Central Sensitization in Cancer Survivors and Its Clinical Implications: State of the Art

Although the prevalence of cancer pain is 47% after treatment, cancer pain is often underestimated, and many patients are undertreated. The complexity of cancer pain contributes to the lack of its management. Recently, as the mechanism of cancer pain, it has become clear that central sensitization (CS) influences chronic pain conditions and the transition from acute to chronic pain. In this state-of-the-art review, we summarized the association of CS or central sensitivity syndrome with pain and the treatment for pain targeting CS in cancer survivors. The management of patients with CS should not only focus on tissue damage in either the affected body regions or within the central nervous system; rather, it should aim to target the underlying factors that sustain the CS process. Pain neuroscience education (PNE) is gaining popularity for managing chronic musculoskeletal pain and could be effective for pain and CS in breast cancer survivors. However, there is a study that did not demonstrate significant improvements after PNE, so further research is needed. Precision medicine involves the classification of patients into subgroups based on a multifaceted evaluation of disease and the implementation of treatment tailored to the characteristics of each patient, which may play a central role in the treatment of CS.

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.

Effectiveness of three exercise programs and intensive follow-up in improving quality of life, pain, and lymphedema among breast cancer survivors: a randomized, controlled 6-month trial

PURPOSE

Postoperative complications of breast cancer (BC) seriously affect the quality of life (QOL) of survivors. Physical activity is related to prevention of complications and improvement of QOL. Follow-up can keep patients motivated to exercise. This study aimed to (1) compare the effect of three exercise programs on lymphedema, pain, and QOL in BC patients and (2) explore the effect of intensive follow-up on the outcomes of exercise programs.

METHODS

A single-blind randomized parallel controlled trial with a 6-month intervention was carried out in China in 2021. The study sample included 200 women with BC. The patients were randomly divided into 4 groups. G₀ (control group) was joint mobility exercise (JME) group; G₁ was joint mobility exercise + intensive follow-up (IF) group; G₂ was JME + aerobic exercise (AE) + IF group; and G₃ was JME + progressive resistance exercise (PRE) + IF group. Outcome measures were evaluated at baseline (T₁), 3 months post-intervention (T₂), and 6 months post-intervention (T₃). The following instruments and measurements were administered before and after the intervention: the Functional Assessment of Cancer Therapy-Breast (FACT-B) instrument, the numerical rating scale (NRS), and the relative volume change (RVC). Verificating aim 1 is by comparing the results of G₁, G₂, and G₃, and verificating aim 2 is achieved by comparing G₀ and G₁. Differences before and after the intervention were determined by analysis of variance of repeated measures and Kruskal-Wallis nonparametric analysis of variance.

RESULTS

Among the exercise programs, JME + PRE + IF resulted in the best improvement in QOL (T2: ΔG₃-G₀ = 13.032, P = 0.008; T2: ΔG₃-G₁ = 13.066, P < 0.001; ΔG₃-G₀ = 17.379, P < 0.001). For pain relief, JME + AE + IF had the best improvement (T3: ΔG₂-G₁ =  - 0.931, P = 0.010; ΔG₂-G₀ =  - 1.577, P < 0.001). For the prevention of lymphedema, JME + AE + IF (Z = 2.651, P = 0.048) and JME + PRE + IF (Z = 3.277, P = 0.006) had the similar effect, but JME + PRE + IF is better than JME + AE + IF.

CONCLUSION

JME + PRE have the best effect in improving the QOL and preventing lymphedema after surgery. In improving pain, the effect of JME + AE appears earlier, and the overall effect of JME + PRE is better. In addition, long-term and planned monitoring and follow-up are also important.

Determinants of Pain-Induced Disability in German Women with Endometriosis during the COVID-19 Pandemic

(1) Background: The main aim of this research was to examine the factors leading to pain-induced disability by assessing the impact of demographic, endometriosis-specific, pandemic-specific, and mental health factors. (2) Methods: Women with endometriosis who attended online support groups were invited to respond to an online survey during the first wave of the COVID-19 pandemic in Germany. The Pain Disability Index (PDI) was employed to assess disability-related daily functioning. Independent predictors of pain-induced disability were determined using univariate and multivariate logistic regression analyses. (3) Results: The mean PDI score of the study population was 31.61 (SD = 15.82), which was significantly higher (p < 0.001) than that reported in a previously published normative study of the German population. In the present study, a high level of pain-induced disability, as defined by scores equal to or higher than the median of the study population, older age (OR 1.063, 95% CI 1.010−1.120, p = 0.020), dysmenorrhea (OR 1.015, 95% CI 1.005−1.026, p = 0.005), dysuria (OR 1.014; 95% CI 1.001−1.027, p = 0.029), lower back pain (OR 1.018, 95% CI 1.007−1.029, p = 0.001), and impaired mental health (OR 1.271, 95% CI 1.134−1.425, p < 0.001) were found to be independent risk factors. Pandemic-specific factors did not significantly influence the pain-induced disability of the participants in this study. (4) Conclusions: The level of pain-induced disability was significantly higher among the women with endometriosis than among women in the normative German validation study. Our findings identified risk factors for experiencing a high level of pain-induced disability, such as demographic and specific pain characteristics. Pandemic-specific factors did not significantly and independently influence the pain-induced disability during the first wave of the COVID-19 pandemic in Germany. Impaired mental health negatively influenced functioning during daily activities. Thus, women with endometriosis should be managed by a multidisciplinary team of healthcare professionals to prevent negative effects of pain-induced disability on their quality of life.

Quality Assessment of Cancer Pain Clinical Practice Guidelines

Introduction

Several clinical practice guidelines (CPGs) for cancer pain have been published; however, the quality of these guidelines has not been evaluated so far. The purpose of this study was to evaluate the quality of CPGs for cancer pain and identify gaps limiting knowledge.

Methods

We systematically searched seven databases and 12 websites from their inception to July 20, 2021, to include CPGs related to cancer pain. We used the validated Appraisal of Guidelines for Research and Evaluation Instrument II (AGREE II) and Reporting Items for Practice Guidelines in Healthcare (RIGHT) checklist to assess the methodology and reporting quality of eligible CPGs. The overall agreement among reviewers with the intraclass correlation coefficient (ICC) was calculated. The development methods of CPGs, strength of recommendations, and levels of evidence were determined.

Results

Eighteen CPGs published from 1996 to 2021 were included. The overall consistency of the reviewers in each domain was acceptable (ICC from 0.76 to 0.95). According to the AGREE II assessment, only four CPGs were determined to be recommended without modifications. For reporting quality, the average reporting rates for all seven domains of CPGs was 57.46%, with the highest domain in domain 3 (evidence, 68.89%) and the lowest domain in domain 5 (review and quality assurance, 33.3%).

Conclusion

The methodological quality of cancer pain CPGs fluctuated widely, and the complete reporting rate in some areas is very low. Researchers need to make greater efforts to provide high-quality guidelines in this field to clinical decision-making.