Understanding the Psychological, Physiological, and Genetic Factors Affecting Precision Pain Medicine: A Narrative Review

Validation of the Keele STarT MSK Tool for Patients With Musculoskeletal Pain in United States-based Outpatient Physical Therapy Settings

The STarT MSK tool was developed to enable risk stratification of patients with common musculoskeletal (MSK) pain conditions and help identify individuals who may require more targeted interventions or closer monitoring in primary care settings, however, its validity in U.S.-based outpatient physical therapy settings has not been investigated. The 10-item Keele STarT MSK risk stratification tool was tested for construct (convergent and discriminant) and predictive validity using a multicenter, prospective cohort study design. Participants (n = 141) receiving physical therapy for MSK pain of the back, neck, shoulder, hip, knee, or multisite regions completed intake questionnaires including the Keele STarT MSK tool, Functional Comorbidity Index (FCI), Optimal Screening for Prediction of Referral and Outcome Review-of-Systems and Optimal Screening for Prediction of Referral and Outcome Yellow Flag tools. Pain intensity, pain interference, and health-related quality of life (Medical Outcomes Study 8-item Short-Form Health Survey (SF-8) physical [PCS] and mental [MCS] component summary scores) were measured at 2- and 6-month follow-up. Participants were classified as STarT MSK tool low (44%), medium (39%), and high (17%) risk. Follow-up rates were 70.2% (2 months) and 49.6% (6 months). For convergent validity, fair relationships were observed between the STarT MSK tool and FCI and SF-8 MCS (r = .35-.37) while moderate-to-good relationships (r = .51-.72) were observed for 7 other clinical measures. For discriminant validity, STarT MSK tool risk-dependent relationships were observed for Optimal Screening for Prediction of Referral and Outcome Review-of-Systems, Optimal Screening for Prediction of Referral and Outcome Yellow Flag, pain interference, and SF-8 PCS (low < medium < high; P < .01) and FCI, pain intensity, and SF-8 MCS (low < medium-or-high; P < .01). For predictive validity, intake STarT MSK tool scores explained additional variability in pain intensity (11.2%, 20.0%), pain interference (7.5%, 14.1%), and SF-8 PCS (8.2%, 12.8%) scores at 2 and 6 months, respectively. This study contributes to the existing literature by providing additional evidence of STarT MSK tool cross-sectional construct validity and longitudinal predictive validity. PERSPECTIVE: This study presents STarT MSK risk stratification tool validity findings from a U.S. outpatient physical therapy sample. The STarT MSK tool has the potential to help physical therapists identify individuals presenting with the most common MSK pain conditions who may require more targeted interventions or closer monitoring.

COMT Variants are Associated With Breast and Nipple Pain

Estimates suggest that only 24.9% of infants born in 2019 were exclusively breastfed before 6 months of age, despite the known health benefits of exclusive breastfeeding. Breast and nipple pain is one of the primary determinants of exclusive breastfeeding. Environmental contributions to breastfeeding success have been reported extensively in the literature, but the contribution(s) of maternal genetics has yet to be discovered. The purpose of the study was to identify an association between pain and lactation-related gene variants with exclusive breastfeeding determinants. We selected 4 genes having single nucleotide polymorphisms (SNPs) with potential functional significance in breastfeeding and pain: prolactin receptor (PRLR), oxytocin receptor (OXTR), catechol-O-methyltransferase (COMT), and milk fat globule epidermal growth factor and factor V/VIII domain containing (MFGE8). We performed a cross-sectional secondary analysis of a longitudinal randomized controlled trial study, Promoting Self-Management of Breast and Nipple Pain with Biomarkers and Technology for Breastfeeding Women (NCT05262920). Breast and nipple pain, perceived insufficient milk, and breastfeeding self-efficacy were examined using total scale scores for the Brief Pain Inventory, Visual Analog Scale, H&H Lactation Scale, and the Breastfeeding Self-efficacy Scale-short form, respectively. Of the candidate genes examined, SNPs within COMT were significantly associated with breastfeeding-related outcomes. Specifically, COMT rs4633 and rs4680 minor allele carriers (T, A) reported higher breast and nipple pain intensity than women homozygous for the major allele (C, G). COMT is the most widely researched "pain gene" and has been linked to cold, postoperative, and postpartum pain. This study is the first to identify a contribution of COMT variants to breast and nipple pain and, as a result, to breastfeeding exclusivity. PERSPECTIVE: Two SNPs in the pain gene COMT are associated with breast and nipple pain. Clinically, a minor allele in COMT rs4633 and rs4680 may increase a woman's rating of moderate breast and nipple pain. TRIAL REGISTRATION: PROMPT was registered in ClinicalTrials.gov (protocol #NCT05262920).

Sex moderates the association between quantitative sensory testing and acute and chronic pain after total knee/hip arthroplasty

OBJECTIVES

Acute postsurgical pain (APSP) may persist over time and become chronic. Research on predictors for APSP and chronic postsurgical pain (CPSP) has produced inconsistent results. This observational study aimed to analyze psychological and psychophysical variables associated with APSP and CPSP after total knee or hip arthroplasty, and to explore the role of sex.

METHODS

Assessments were conducted before surgery, 48 h, and 3 months postsurgery, including questionnaires (sociodemographic, pain related, and psychological) and quantitative sensory testing (QST). Hierarchical linear regression models analyzed potential predictors of APSP and CPSP, and moderation analyses evaluated the role of sex.

RESULTS

The study included 63 participants undergoing total knee (34, 54%) or hip (29, 46%) arthroplasty. Thirty-one (49.2%) were female and 32 (50.8%) were male. APSP (48 h) was associated with impaired conditioned pain modulation (CPM) (β = 0.301, p = 0.019). CPSP (3 months) was associated with being female (β = 0.282, p = 0.029), longer presurgical pain duration (β = 0.353, p = 0.006), knee arthroplasty (β = -0.312, p = 0.015), higher APSP intensity (β = 373, p = 0.004), and impaired CPM (β = 0.126, p = 0.004). In multivariate analysis, these clinical variables were significant predictors of CPSP, unlike sex, and CPM (adj. R 2 = 0.349). Moderation analyses showed that wind-up ratio (WUR) was a significant predictor of APSP in men (WUR × sex: b = -1.373, p = 0.046) and CPM was a significant predictor of CPSP in women (CPM × sex: b = 1.625, p = 0.016).

CONCLUSIONS

Specific QST parameters could identify patients at risk for high-intensity APSP and CPSP, with sex as a moderator. This has important clinical implications for patient care, paving the way for developing tailored preventive pain management strategies.

Challenges and Opportunities in Developing Tailored Pain Management Strategies for Liver Patients

Chronic liver illnesses pose a substantial worldwide health challenge, with various causes that span from viral infections to metabolic problems. Individuals suffering from liver problems frequently face distinct difficulties in pain control, requiring a customized strategy that takes into account both the fundamental disease and the complexities of liver function. The liver, a vital organ responsible for metabolic control and detoxification, is pivotal in multiple physiological processes. Chronic liver illnesses, such as cirrhosis and non-alcoholic fatty liver disease (NAFLD), are marked by a gradual process of inflammation and fibrosis, resulting in reduced liver function. These disorders often come with pain, varying from internal discomfort to intense abdominal pain, which impacts the quality of life and general well-being of patients. The review explores the complex aspects of pain perception in liver illnesses, including inflammation, modified neuronal signaling, and the influence of comorbidities. It highlights the significance of a detailed comprehension of the pain experience in individuals with hepatic conditions for the implementation of successful pain management treatments. In addition, the review emphasizes the difficulties involved in treating pain in this group of patients, such as the possible complications linked to commonly prescribed pain relievers and the necessity for collaboration between hepatologists, pain specialists, and other healthcare professionals. Moreover, it examines new possibilities in the domain, such as the significance of innovative pharmacological substances, non-pharmacological treatments, and personalized medicine strategies designed for specific patient characteristics. This study thoroughly analyzes the difficulties and possibilities involved in creating personalized pain management approaches for individuals with liver conditions. Its purpose is to guide physicians, researchers, and healthcare providers, enabling them to implement more efficient and patient-focused interventions. As our comprehension of liver-related pain progresses, the potential for enhancing the quality of life for persons with chronic liver disorders through tailored pain management measures becomes more and more encouraging.

Goals, Expectations, and the Definition of Success for Neuromodulation for Pain According to Representatives of Neuromodulation Device Manufacturers

Representatives of neuromodulation device manufacturers are expected to facilitate the relationship between patients and healthcare providers. Nevertheless, the goals, expectations, and definition of success for neuromodulation for pain have not yet been explored. Representatives present at the 2nd Joint Congress of the INS European Chapters in September 2021 completed a survey to ascertain their opinions about the goals to achieve with neuromodulation, the factors that they expect to change, and their definition of success for neuromodulation. In total, 39 representatives completed the survey. To provide excellent service for patients (22.4%), to become a trusted partner for physicians (21.5%), and to provide excellent service for physicians (20.7%) were the highest ranked goals. The most frequently reported factors that were expected to change were pain intensity (23.1%), patient satisfaction (19.7%), mobility/functioning (14.5%), and capacity to return to work (13.7%). Within the definitions of success, increased quality of life of the patient was stated in 21% of the definitions, closely followed by pain control (19.3%) and happiness/patient satisfaction (15.8%). The goals of representatives of neuromodulation device manufacturers seem to focus on ensuring a good relationship with physicians on the one hand and providing good service towards patients on the other hand, whereby pain control, quality of life, and patient satisfaction seem to be important for company representatives.

Patient Selection for Spinal Cord Stimulation in Treatment of Pain: Sequential Decision-Making Model - A Narrative Review

Despite the well-known efficacy of spinal cord stimulation (SCS) in chronic pain management, patient selection in clinical practice remains challenging. The aim of this review is to provide an overview of the factors that can influence the process of patient selection for SCS treatment. A sequential decision-making model is presented within a tier system that operates in clinical practice. The first level incorporates the underlying disease as a primary indication for SCS, country-related reimbursement rules, and SCS screening-trial criteria in combination with underlying psychological factors as initial selection criteria in evaluating patient eligibility for SCS. The second tier is aligned with the individualized approach within precision pain medicine, whereby individual goals and expectations and the potential need for preoperative optimizations are emphasized. Additionally, this tier relies on results from prediction models to provide an estimate of the efficacy of SCS in the long term. In the third tier, selection bias, MRI compatibility, and ethical beliefs are included, together with recent technological innovations, superiority of specific stimulation paradigms, and new feedback systems that could indirectly influence the decision-making of the physician. Both patients and physicians should be aware of the different aspects that influence patient selection in relation to SCS for pain management to make an independent decision on whether or not to initiate a treatment trajectory with SCS.

Impact of BRCA Status on Reproductive Decision-Making and Self-Concept: A Mixed-Methods Study Informing the Development of Tailored Interventions

This mixed-methods study sought to deepen our understanding of self-concept and experiences in balancing cancer risk/reproductive decisions after learning of BRCA+ status. First, a quantitative survey of BRCA+ women (n = 505) examined the childbearing status, risk-reducing surgery, and self-concept. At the time of testing, 307/505 (60.8%) women were of reproductive age (<40 years-old), 340/505 (67.3%) had children, and 317/505 (62.8%) had undergone risk-reducing surgery. A younger age at the time of the testing was significantly associated with the decision to have children after learning BRCA+ status or undergoing risk-reducing surgery (p < 0.001). Compared to older women, BRCA+ women of reproductive age, exhibited a more negative self-concept with significantly higher vulnerability ratings (p < 0.01). Women with a cancer diagnosis exhibited a more negative mastery ratings and worse vulnerability ratings (p < 0.01) than women without a cancer history. Compared to childless counterparts, significantly higher vulnerability ratings were observed among BRCA+ women who had children before learning their BRCA status and/or undergoing risk-reducing surgery (p < 0.001). Subsequently, a subset of women (n = 40) provided in-depth interviews to explore their experiences in decision-making. The interviews provided insights into the effects of BRCA status on decisions regarding relationships, childbearing, cancer risk management, and communicating BRCA risk to children. Integrating quantitative and qualitative findings identifies targets for tailored interventions to enhance precision health for BRCA+ women of reproductive age.

Neurofeedback Therapy for Sensory Over-Responsiveness-A Feasibility Study

Background: Difficulty in modulating multisensory input, specifically the sensory over-responsive (SOR) type, is linked to pain hypersensitivity and anxiety, impacting daily function and quality of life in children and adults. Reduced cortical activity recorded under resting state has been reported, suggestive of neuromodulation as a potential therapeutic modality. This feasibility study aimed to explore neurofeedback intervention in SOR. Methods: Healthy women with SOR (n = 10) underwent an experimental feasibility study comprising four measurement time points (T1—baseline; T2—preintervention; T3—postintervention; T4—follow-up). Outcome measures included resting-state EEG recording, in addition to behavioral assessments of life satisfaction, attaining functional goals, pain sensitivity, and anxiety. Intervention targeted the upregulation of alpha oscillatory power over ten sessions. Results: No changes were detected in all measures between T1 and T2. Exploring the changes in brain activity between T2 and T4 revealed power enhancement in delta, theta, beta, and gamma oscillatory bands, detected in the frontal region (p = 0.03−<0.001; Cohen’s d = 0.637−1.126) but not in alpha oscillations. Furthermore, a large effect was found in enhancing life satisfaction and goal attainment (Cohen’s d = 1.18; 1.04, respectively), and reduced pain sensitivity and anxiety trait (Cohen’s d = 0.70). Conclusion: This is the first study demonstrating the feasibility of neurofeedback intervention in SOR.