Race, Social Status, and Depressive Symptoms: A Moderated Mediation Analysis of Chronic Low Back Pain Interference and Severity

Adverse Childhood Experiences and Chronic Low Back Pain in Adulthood: The Role of Emotion Regulation

Chronic low back pain (cLBP) is characterized by biopsychosocial determinants that collectively result in a substantial burden at the individual, community, and health care system levels. A growing body of literature suggests that childhood adversity is longitudinally associated with the development and maintenance of various chronic pain conditions in adulthood. Little research has investigated the psychological processes that might underlie the association between adverse childhood experiences (ACEs) and cLBP. Emotion regulation comprises a substantive part of the subjective experience of pain and may be a potential mechanism through which ACEs contribute to cLBP etiology and maintenance. Thus, the current study examined the extent to which emotion dysregulation mediated the relationship between ACEs and pain severity (pain at rest and movement-evoked pain) in adults with cLBP. Participants included 183 adults (53.0% female, 62.5% non-Hispanic Black) between the ages of 18 and 85 with cLBP. Participants self-reported on ACEs, pain, difficulties in emotion regulation (DER), depression, and completed brief physical function tasks. In data analytic models, sociodemographic variables were included as covariates. Analyses revealed that emotion regulation mediated the relationship between ACEs and cLBP severity at rest (indirect effect = .15 [95% CI {.06-.25}]) and with movement (indirect effect = 1.50 [95% CI {.69-2.57}]). Findings suggest ACEs are linked to cLBP severity in adulthood through DER. This aligns with research demonstrating that childhood maltreatment can lead to DER, which perpetuate over the lifespan to impact adult health outcomes. PERSPECTIVE: This study presents emotion dysregulation as a psychological pathway through which childhood adversity may contribute to cLBP in adulthood. This work may bolster our understanding of social experiences as risk factors for chronic pain, while identifying targets for clinical intervention. TRIAL REGISTRATION: This study utilized baseline data collected as part of a parent trial titled "Examining Racial and SocioEconomic Disparities in Chronic Low Back Pain" (ClinicalTrials.gov ID: NCT03338192).

Biobehavioral Predictors of Pain Intensity, Pain Interference, and Chronic Pain Episodes: A Prospective Cohort Study of African-American Adults

Racial disparities in pain experiences are well-established, with African-American (AA) adults reporting higher rates of daily pain, increased pain severity, and greater pain-related interference compared to non-Hispanic Whites. However, the biobehavioral factors that predict the transition to chronic pain among AA adults are not well understood. This prospective cohort study provided a unique opportunity to evaluate predictors of chronic pain onset among 130 AA adults (81 women), ages 18 to 44, who did not report chronic pain at their baseline assessment and subsequently completed follow-up assessments at 6- and 12-months. Outcome measures included pain intensity, pain-related interference, and chronic pain status. Comprehensive assessments of sociodemographic and biobehavioral factors were used to evaluate demographics, socioeconomic status, stress exposure, psychosocial factors, prolonged hypothalamic-pituitary-adrenal secretion, and quantitative sensory testing responses. At baseline, 30 adults (23.1%) reported a history of prior chronic pain. Over the 12-month follow-up period, 13 adults (10.0%) developed a new chronic pain episode, and 18 adults (13.8%) developed a recurrent chronic pain episode. Whereas socioeconomic status measures (ie, annual income, education) predicted changes in pain intensity over the follow-up period, quantitative sensory testing measures (ie, pain threshold, temporal summation of pain) predicted changes in pain interference. A history of chronic pain and higher depressive symptoms at baseline independently predicted the onset of a new chronic pain episode. The present findings highlight distinct subsets of biobehavioral factors that are differentially associated with trajectories of pain intensity, pain-related interference, and onset of chronic pain episodes in AA adults. PERSPECTIVE: This prospective study sought to advance understanding of biobehavioral factors that predicted pain outcomes over a 12-month follow-up period among AA adults without chronic pain at their initial assessment. Findings revealed distinct subsets of factors that were differentially associated with pain intensity, pain-related interference, and onset of chronic pain episodes.

Racial Differences in Movement-Related Appraisals and Pain Behaviors Among Adults With Chronic Low Back Pain

Research documents racial disparities in chronic low back pain (CLBP). Few studies have examined racial disparities in movement-related appraisals and no studies have examined anticipatory appraisals prior to or pain behaviors during functional activities among individuals with CLBP. This cross-sectional study examined racial differences in anticipatory appraisals of pain, concerns about harm, and anxiety, appraisals of pain and anxiety during movement, and observed pain behaviors during 3 activities of daily living (supine-to-standing bed task, sitting-to-standing chair task, floor-to-waist lifting task) in a sample (N = 126) of non-Hispanic Black (31.0%), Hispanic (30.2%), and non-Hispanic White (38.9%) individuals with CLBP. Hispanic participants reported more expected pain, concerns about harm, and pre-movement anxiety prior to the bed and chair tasks compared to non-Hispanic White participants. Hispanic participants reported more pain during the bed task and more anxiety during the bed and chair tasks compared to non-Hispanic White participants. Non-Hispanic Black participants reported more expected pain, concerns about harm, and pre-movement anxiety prior to the bed task and more pre-movement anxiety prior to the chair task compared to non-Hispanic White participants. Non-Hispanic Black participants reported more anxiety during the bed and chair tasks compared to non-Hispanic White participants. Non-Hispanic Black participants were observed to have significantly more verbalizations of pain during the bed task compared to non-Hispanic White participants. Current findings identify racial disparities in important cognitive-behavioral and fear-avoidance mechanisms of pain. Results indicate a need to revisit traditional theoretical and treatment models in CLBP, ensuring racial disparities in pain cognitions are considered. PERSPECTIVE: This study examined racial disparities in anticipatory and movement-related appraisals, and pain behaviors during activities of daily living among Non-Hispanic Black, Non-Hispanic White, and Hispanic individuals with CLBP. Racial disparities identified in the current study have potentially important theoretical implications surrounding cognitive-behavioral and fear-avoidance mechanisms of pain.

Considerations beyond spine pain: do different co-occurring lower body joint pains differentially influence physical function and quality of life ratings?

BACKGROUND

Patients seeking medical care for back pain often have coexisting painful joints and the effects of different combinations and number of coexisting pain sites (hip, knee, foot/ankle) to back pain on physical function domains and quality of life rating are not yet established. The purpose of this study was to determine the differences in functional outcomes and QOL among individuals with back pain who have concurrent additional pain sites or no pain sites.

METHODS

Data from the Osteoarthritis Initiative (OAI) cohort were used for this cross-sectional analysis. Men and women aged 45-79 years with back pain were binned into nine groups by presence or not of coexisting hip, knee, ankle/foot pain and combinations of these sites (N = 1,642). Healthy controls reported no joint pain. Main outcomes included Knee Injury and Osteoarthritis Outcome score (KOOS; quality of life and function-sports-and-recreation), Western Ontario McMaster Universities Osteoarthritis Index (WOMAC; Activities of Daily Living, Pain), Medical Outcomes Short Form-12 (SF-12) Physical Component score, and self-reported function in last 7-30 days (lifting 25-pound objects, housework). 20-m and 400-m walk times and gait speed and repeated chair rise test times were collected.

RESULTS

Compared to back pain alone, pain at all five sites was associated with 39%-86% worse KOOS, WOMAC, and SF-12 scores (p < .0001). Back-Hip and Back-Knee did not produce worse scores than Back pain alone, but Back-Hip-Knee and Back-Knee-Ankle/Foot did. The 20-m, 400-m walk, and repeated chair times were worse among individuals with pain at all five sites. Additional hip and knee sites to back pain, but not ankle/foot, worsened performance-based walk times and chair rise scores.

CONCLUSIONS

The number and type of coexistent lower body musculoskeletal pain among patients with back pain may be associated with perceived and performance-based assessments. Management plans that efficiently simultaneously address back and additional coexistent pain sites may maximize treatment functional benefits, address patient functional goals in life and mitigate disability.

The Pace of Biological Aging Predicts Nonspecific Chronic Low Back Pain Severity

This study aimed to determine if and how the pace of biological aging was associated with nonspecific chronic low back pain (cLBP) and compare what measure of epigenetic age acceleration most strongly predicts cLBP outcomes. We used the Dunedin Pace of Aging from the Epigenome (DunedinPACE), Horvath's, Hannum's, and PhenoAge clocks to determine the pace of biological aging in 69 cLBP, and 49 pain-free controls (PFCs) adults, ages 18 to 85 years. On average, participants with cLBP had higher DunedinPACE (P < .001) but lower Horvath (P = .04) and Hannum (P = .02) accelerated epigenetic age than PFCs. There was no significant difference in PhenoAge acceleration between the cLBP and PFC groups (P = .97). DunedinPACE had the largest effect size (Cohen's d = .78) on group differences. In univariate regressions, a unit increase in DunedinPACE score was associated with 265.98 times higher odds of cLBP than the PFC group (P < .001). After controlling for sex, race, and body mass index (BMI), the odds ratio of cLBP to PFC group was 149.62 (P < .001). Furthermore, among participants with cLBP, DunedinPACE scores positively correlated with pain severity (rs = .385, P = .001) and interference (rs = .338, P = .005). Epigenetic age acceleration from Horvath, Hannum, and PhenoAge clocks were not significant predictors of cLBP. The odds of a faster pace of biological aging are higher among adults with cLBP, and this was associated with greater pain severity and disability. Future interventions to slow the pace of biological aging may improve cLBP outcomes. PERSPECTIVE: Accelerated epigenetic aging is common among adults with nonspecific cLBP. Higher DunedinPACE scores positively correlate with pain severity and interference, and better predict cLBP than other DNA methylation clocks. Interventions to slow the pace of biological aging may be viable targets for improving pain outcomes.

The use of a biopsychosocial model in the treatment of patients with chronic

OBJECTIVE

To explore the available knowledge on the application of biopsychosocial model (BPS) in patients with chronic low back pain (CLBP).

METHODS

A scoping review, including 32 papers that used a BPS to manage adult patients with CLBP, published in any language. Six different databases were searched.

RESULTS

According to the description of the protocols, most of them use BPS for assessment of the patients. In this first stage the most often evaluated were pain and disability, kinesiophobia and quality of life, and work-related factors. The intervention most used associate psychological and physical domains using pain education or cognitive functional therapy and active exercise. Even though was not the most common, in the social domain occupational, behavioral and family interventions were observed.

CONCLUSION

BPS is more often used as combination of physical and psychological aspects, being the social domain restricted to work-related factors. Patien'ts perception of their health status is little explored, and it is suggested that the International Classification of Functioning, Disability and Health be used.

PRACTICE IMPLICATION

Patient perception as well as social factors in addition to occupational ones should be included in the clinical approach of the patient with CLBP and should be further explored in research.

Pain and Menthol Use Are Related to Greater Nicotine Dependence Among Black Adults Who Smoke Cigarettes at Wave 5 (2018-2019) of the Population Assessment of Tobacco and Health (PATH) Study

Burdens related to pain, smoking/nicotine dependence, and pain-smoking comorbidity disproportionately impact Black Americans, and menthol cigarette use is overrepresented among Black adults who smoke cigarettes. Menthol may increase nicotine exposure, potentially conferring enhanced acute analgesia and driving greater dependence. Therefore, the goal of the current study was to examine associations between pain, menthol cigarette use, and nicotine dependence. Data was drawn from Black adults who were current cigarette smokers (n = 1370) at Wave 5 (2018-2019) of the Population Assessment of Tobacco and Health Study. Nicotine dependence was assessed using the Wisconsin Inventory of Smoking Dependence Motives. ANCOVA revealed that moderate/severe pain (vs. no/low pain) was associated with greater overall nicotine dependence (p < .001) and greater negative reinforcement, cognitive enhancement, and affiliative attachment smoking motives (ps < .001). Menthol smokers with moderate/severe pain also endorsed greater cigarette craving and tolerance, compared to non-menthol smokers with no/low pain (ps < .05). Findings support the notion that among Black individuals who smoke cigarettes, the presence of moderate/severe pain (vs. no/low pain) and menthol use may engender greater physical indices of nicotine dependence relative to non-menthol use. Compared to no/low pain, moderate/severe pain was associated with greater emotional attachment to smoking and greater proclivity to smoke for reducing negative affect and enhancing cognitive function. Clinical implications include the need to address the role of pain and menthol cigarette use in the assessment and treatment of nicotine dependence, particularly among Black adults. These data may help to inform evolving tobacco control policies aimed at regulating or banning menthol tobacco additives.

The mediating effect of allostatic load on the association between life course socioeconomic disadvantage and chronic pain: a prospective finding from the National Survey of Midlife Development in the United States

Background

Socioeconomic disadvantages (SEDs) are associated with chronic pain (CP) and allostatic load (AL). Few prospective population-based studies have examined the relationship between life course SED, CP interference, and CP widespreadness, and there is no prospective population-based study on whether AL mediates the association between SED and CP.

Objective

In this study, we investigated whether the prospective effect of SED on CP at Midlife in the United States (MIDUS) 3 is consistent with the accumulation of risk model and social mobility model, using the National Survey of MIDUS (n = 593). To prepare for the mediation analysis, we tested (1) whether SED would be prospectively associated with AL in the MIDUS 2 biomarker project, (2) whether AL would be prospectively associated with CP, and (3) whether childhood, as a critical period, moderated the association between AL and CP. In addition, the mediating effect of AL on the association between SED and CP was examined.

Method

SED was measured using cumulative scores and disadvantage trajectories derived from latent class trajectory modeling (LCTM). After multiple imputations, analyses were conducted using multinomial logistic regression for CP and negative binomial regression for AL, respectively. Finally, mediation analyses and moderated mediation analyses were performed.

Results

LCTM identified three SED trajectories, namely, constant low, high to low, and medium to high. The results showed that proximal cumulative SED was associated with high-interference CP. Furthermore, compared with the group with constant low SED, the group with medium-to-high SED was significantly associated with high-interference pain and experienced pain in at least three different sites. Cumulative SED and deteriorating SED trajectories were associated with higher AL, consistent with previous studies. Furthermore, childhood SED moderated the effect of AL on CP widespreadness and unexpectedly demonstrated a protective effect, while other associations between AL and CP were not significant. Subsequent mediation analysis did not yield statistically significant evidence.

Conclusions

People who experienced more recent SED or increasing disadvantage throughout their lives were more likely to suffer from CP, and this association was not mediated by physiological system dysregulation caused by chronic stress. Therefore, measures to alleviate AL may not be effective in protecting socioeconomically disadvantaged populations from CP.

Disparities in chiropractic utilization by race, ethnicity and socioeconomic status: A scoping review of the literature

BACKGROUND

Chiropractic is the largest complementary and alternative medicine profession in the United States, with increasing global growth. A preliminary literature review suggests a lack of widespread diversity of chiropractic patient profiles.

OBJECTIVE

There have been no prior studies to comprehensively integrate the literature on chiropractic utilization rates by race, ethnicity, and socioeconomic status. The purpose of this scoping review is to identify and describe the current state of knowledge of chiropractic utilization by race, ethnicity, education level, employment status, and income and poverty level.

SEARCH STRATEGY

Systematic searches were conducted in PubMed, Ovid MEDLINE, Cumulative Index of Nursing and Allied Health Literature (CINAHL), Cochrane Database of Systematic Reviews, and Index to Chiropractic Literature from inception to May 2021.

INCLUSION CRITERIA

Articles that reported race or ethnicity, education level, employment status, income or poverty level variables and chiropractic utilization rates for adults (≥18 years of age) were eligible for this review.

DATA EXTRACTION AND ANALYSIS

Data extracted from articles were citation information, patient characteristics, race and ethnicity, education level, employment status, income and poverty level, and chiropractic utilization rate. A descriptive numerical summary of included studies is provided. This study provides a qualitative thematic narrative of chiropractic utilization with attention to race and ethnicity, education level, income and poverty level, and employment status.

RESULTS

A total of 69 articles were eligible for review. Most articles were published since 2003 and reported data from study populations in the United States. Of the race, ethnicity and socioeconomic categories that were most commonly reported, chiropractic utilization was the highest for individuals identifying as European American/White/non-Hispanic White/Caucasian (median 20.00%; interquartile range 2.70%-64.60%), those with employment as a main income source (median utilization 78.50%; interquartile range 77.90%-79.10%), individuals with an individual or household/family annual income between $40,001 and $60,000 (median utilization 29.40%; interquartile range 25.15%-33.65%), and individuals with less than or equal to (12 years) high school diploma/general educational development certificate completion (median utilization 30.70%; interquartile range 15.10%-37.00%).

CONCLUSION

This comprehensive review of the literature on chiropractic utilization by race, ethnicity and socioeconomic status indicates differences in chiropractic utilization across diverse racial and ethnic and socioeconomic populations. Heterogeneity existed among definitions of key variables, including race, ethnicity, education level, employment status, and income and poverty level in the included studies, reducing clarity in rates of chiropractic utilization for these populations. Please cite this article as: Gliedt JA, Spector AL, Schneider MJ, Williams J, Young S. Disparities in chiropractic utilization by race, ethnicity and socioeconomic status: a scoping review of the literature. J Integr Med. 2023; Epub ahead of print.

The pace of biological aging helps explain the association between insomnia and chronic low back pain

Chronic low back pain (cLBP) is associated with insomnia and advanced age. Emerging evidence suggests that the severity of both sleep disorders (like insomnia) and chronic pain are associated with a faster pace of biological aging. We aimed to determine whether the pace of biological age mediates the relationship between insomnia and the impact of cLBP in a sample of community-dwelling adults ages 19 to 85 years. Participants (49 with no pain, 32 with low-impact pain, and 37 with high-impact pain) completed sociodemographic, pain, insomnia, and short physical performance battery assessments. We calculated the pace of biological aging using DunedinPACE from blood leukocyte DNA. On average, individuals with high-impact cLBP had significantly faster biological aging than those with low-impact and no chronic pain (p < .001). Bivariate associations of DunedinPACE scores with insomnia severity and functional performance were significant at p < .01 (rs = 0.324 and -0.502, respectively). After adjusting for race and sex, the association of insomnia severity and the impact of cLBP was partially mediated by the pace of biological aging (β = 0.070, p < .001). Also, the association of insomnia severity with functional performance was partially mediated by the pace of biological aging (β = -0.105, p < .001). Thus, insomnia remains strongly predictive of cLBP outcomes, and the pace of biological aging helps explain this association. Future prospective studies with repeated assessments are needed to uncover the directionality of these complex relationships and ultimately develop interventions to manage cLBP.

Genome-wide DNA methylation study identifies significant epigenomic changes associated with internalized stigma in adults with non-specific chronic low back pain

Non-specific chronic low back pain (cLBP) represents a common musculoskeletal condition with no identifiable cause. It cannot be diagnosed with conventional neuroimaging techniques such as computerized tomography (CT). The diagnostic uncertainty that characterizes non-specific cLBP can lead to stigmatizing responses from others that can become internalized Among individuals with non-specific cLBP, internalized stigma is associated with greater pain intensity and disability. Yet, no study has examined the biological mechanism linking high internalized stigma to worse outcomes in individuals with non-specific cLBP. We aimed to identify differentially methylated loci (DML), enrichment pathways, and associated network interactions among individuals with non-specific cLBP experiencing low vs. high internalized stigma. We examined DNA methylation in whole blood samples from 48 adults, ages 19-85, using reduced representation bisulfite sequencing (RRBS). After controlling for age, sex, race, and multiple testing, differentially methylated loci (DML) differed in adults with low vs. high internalized stigma by at least 10% and q < 0.01 in 3,665 CpG sites: 2,280 hypomethylated and 1,385 hypermethylated. Gene ontology (GO) analyses of the annotated genes from these sites revealed significant enrichment of 274 biological processes, 29 cellular components, and 24 molecular functions (adjusted p < 0.05). The top enriched molecular functions regulate protein binding and DNA binding of transcription factor activity. Pathway analyses indicated that many functional genomic pathways, including Hippo Signaling, Melanogenesis, and Pathways in Cancer, were enriched with differentially methylated genes. Also, there was a significant interaction between relevance pathways such as P53, mTOR, PI3K-Akt, and Wnt signaling pathways. These pathways have previously been associated with neuroinflammation, neurodegeneration, and stress-related conditions. Thus, findings point to possible stress-induced DNAm changes as the link between high levels of internalized stigma and worse outcomes in adults with non-specific cLBP.

Disparities Exist in Physical Therapy Utilization and Time to Utilization Between Black and White Patients With Musculoskeletal Pain

OBJECTIVE

Black patients are less likely than White patients to receive physical therapy for musculoskeletal pain conditions. Current evidence, however, is limited to self-reported conditions and health services use. The purpose of this study was to use a large electronic health record database to determine whether a race disparity existed in use of physical therapy within 90 days of a new musculoskeletal diagnosis.

METHODS

Eligible patients (n = 52,384) were sampled from an Optum deidentified electronic health record database of 5 million adults distributed throughout the United States. In this database, patients were designated as "Black" and "White." Patients were eligible if they had a new diagnosis for musculoskeletal neck, shoulder, back, or knee pain between January 1, 2012, and December 31, 2017. Logistic regression and Cox proportional hazard models were computed before and after adjusting for covariates to estimate the association between race and receipt of physical therapy services within 90 days of musculoskeletal pain diagnoses.

RESULTS

Patients were on average 47.5 (SD = 14.9) years of age, 12.8% were Black, 87.2% were White, and 52.7% were female. Ten percent of Black patients and 15.5% of White patients received physical therapy services within 90 days of musculoskeletal pain diagnoses. After adjusting for covariates, White patients were 57% more likely (odds ratio = 1.57; 95% CI = 1.44-1.71) to receive physical therapy compared with Black patients and had significantly shorter time to physical therapy than Black patients (hazard ratio = 1.53; 95% CI = 1.42-1.66).

CONCLUSIONS

In a nationally distributed cohort, Black patients were less likely than White patients to utilize physical therapy and had a longer time to utilization of physical therapy for musculoskeletal pain.

IMPACT

These findings highlight the need to determine the mechanisms underlying the observed disparities and how these disparities influence health outcomes.

The Area Deprivation Index Corresponds Effectively With Other Measures of Objective Socioeconomic Status in Adults With Chronic Low Back Pain

Background and Purpose: How the Area Deprivation Index (ADI) performs compared to other measures of socioeconomic status (SES) is unknown. The study purpose is to compare the ADI and other measures of SES in their ability to predict pain severity/interference. Methods: Four measures of SES were compared-ADI, income, education, and subjective social status (SSS). Results: Pain severity/interference correlated positively with ADI (r = .396/r = .33), and negatively with income (r = -.507/r = -.428) and education (r = -.271/r = -.102). Criterion scores of the pain severity model suggest income performs best (AIC = 428.29/BIC = 436.22), followed by ADI (AIC = 437.24/BIC = 445.17), with education performing least well (AIC = 446.35/BIC = 454.29). Similar results were seen for the pain interference model. Conclusions: Neighborhood-level factors warrant consideration along with individual-level factors when attempting to understand the impact of SES on chronic low back pain.

Characterizing the social support and functioning of a low-threshold medication for opioid use disorder treatment cohort at intake

BACKGROUND

Despite the growing morbidity and mortality rates associated with opioid use disorder, a large gap still exists between treatment need and capacity. Low-threshold clinics utilizing medication for opioid use disorder (MOUD) treatment can increase treatment access but are understudied, and little is known about how patient demographic characteristics are associated with their social support and functioning in these settings.

METHODS

We used multivariate regression to estimate associations between demographic characteristics and self-reported social support or functioning indicators among patients receiving MOUD in a low-threshold clinic using several validated instruments administered at intake: Behavior and Symptom Identification Scale, Brief Pain Inventory, and Life Events Checklist for DSM-5. Patients initiating MOUD treatment between April 1 and December 31, 2017, with complete surveys were included (N=582).

RESULTS

Patients were primarily male (62%), aged 34 or older (53%), non-Hispanic White (79%), separated or not married (86%), and unemployed (64%). Over 20% did not live in a house or apartment in the past month. Women were more likely to "get along" with people outside their family or in social situations and to identify their partner as their source of support. Women, non-White, and older patients were at higher risk of social functioning-disrupting events (physical/sexual assaults or experiencing chronic pain), while employment and housing were protective against exposure to these trauma-related events. However, employment and housing also decreased the odds of talking with others about substance use. The aforementioned results were obtained from multivariate logistic regression models and were significant to p<0.05.

CONCLUSIONS

Variation in support and functioning by demographic characteristics suggests that treatment facilities may benefit from adopting strategies that take baseline disparities in support and functioning into account.

Epigenome-wide DNA methylation profiling of conditioned pain modulation in individuals with non-specific chronic low back pain

BACKGROUND

The pathoanatomic cause of chronic low back pain (cLBP) cannot be identified for up to 90% of individuals. However, dysfunctional processing of endogenous nociceptive input, measured as conditioned pain modulation (CPM), has been associated with cLBP and may involve changes in neuronal gene expression. Epigenetic-induced changes such as DNA methylation (DNAm) have been associated with cLBP.

METHODS

In the present study, the relationship between CPM and DNAm changes in a sample of community-dwelling adults with nonspecific cLBP (n = 48) and pain-free controls (PFC; n = 50) was examined using reduced representation bisulfite sequencing. Gene ontology (GO) term enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were applied to identify key pathways involved in efficient versus deficient CPM.

RESULTS

Based on CPM efficiency, we identified 6006 and 18,305 differentially methylated CpG sites (DMCs) with q values < 0.01 among individuals with cLBP and PFCs, respectively. Most of the DMCs were hypomethylated and annotated to genes of relevance to pain, including OPRM1, ADRB2, CACNA2D3, GNA12, LPL, NAXD, and ASPHD1. In both cLBP and PFC groups, the DMCs annotated genes enriched many GO terms relevant to pain processing, including transcription regulation by RNA polymerase II, nervous system development, generation of neurons, neuron differentiation, and neurogenesis. Both groups also enriched the pathways involved in Rap1-signaling, cancer, and dopaminergic neurogenesis. However, MAPK-Ras signaling pathways were enriched in the cLBP, not the PFC group.

CONCLUSIONS

This is the first study to investigate the genome-scale DNA methylation profiles of CPM phenotype in adults with cLBP and PFCs. Based on CPM efficiency, fewer DMC enrichment pathways were unique to the cLBP than the PFCs group. Our results suggest that epigenetically induced modification of neuronal development/differentiation pathways may affect CPM efficiency, suggesting novel potential therapeutic targets for central sensitization. However, CPM efficiency and the experience of nonspecific cLBP may be independent. Further mechanistic studies are required to confirm the relationship between CPM, central sensitization, and nonspecific cLBP.

Chronic Pain Severity and Sociodemographics: An Evaluation of the Neurobiological Interface

Chronic pain is variably associated with brain structure. Phenotyping based on pain severity may address inconsistencies. Sociodemographic groups also differ in the experience of chronic pain severity. Whether differences by chronic pain severity and/or sociodemographic groups are indicated in pain-related areas of the brain is unknown. Relations between 2 measures of chronic pain severity and brain structure via T1-weighted MRI were investigated and sociodemographic group differences explored. The observational study included 142 community-dwelling (68 non-Hispanic Black [NHB] and 74 non-Hispanic White [NHW]) adults with/at risk for knee osteoarthritis. Relationships between chronic pain severity, sociodemographic groups, and a priori selected brain structures (postcentral gyrus, insula, medial orbitofrontal, anterior cingulate, rostral middle frontal gyrus, hippocampus, amygdala, thalamus) were explored. Chronic pain severity associated with cortical thickness. NHB participants reported lower sociodemographic protective factors and greater clinical pain compared to NHWs who reported higher sociodemographic protective factors and lower clinical pain. Greater chronic pain severity was associated with smaller amygdala volumes in the NHB group and larger amygdala volumes in the NHW group. Brain structure by chronic pain stage differed between and within sociodemographic groups. Overall, chronic pain severity and sociodemographic factors are associated with pain-related brain structures. Our findings highlight the importance of further investigating social and environmental contributions in the experience of chronic pain to unravel the complex array of factors contributing to disparities. PERSPECTIVE: The study presents data demonstrating structural brain relationships with clinical pain severity, characteristic pain intensity and chronic pain stage, differ by sociodemographic groups. Findings yield insights into potential sources of previous inconsistent pain-brain relationships and highlights the need for future investigations to address social and environmental factors in chronic pain disparities research.

Differential DNA methylation in Black and White individuals with chronic low back pain enrich different genomic pathways

Compared to Non-Hispanic Whites (NHWs), individuals who self-identify as Non-Hispanic Blacks (NHBs) in the United States experience more severe and disabling chronic low back pain (cLBP). We hypothesized that differences in DNA methylation (DNAm) play a role in racial disparities in cLBP.

PURPOSE

To determine the relationship between DNAm levels and racial group differences in adults with cLBP. Our study's secondary purpose was to perform a race-stratified comparison of adults with cLBP and pain-free controls and identify functional genomic pathways enriched by annotated differentially methylated genes.

PATIENTS AND METHODS

We recruited 49 NHBs and 49 NHWs (49 cLBP and 49 pain-free controls, PFCs), analyzed DNAm from whole blood using reduced representation bisulfite sequencing, and identified enriched genomic pathways.

RESULTS

Among participants with cLBP, we identified 2873 differentially methylated loci (DML; methylation differences of at least 10% and p < 0.0001), many of which were annotated to genes of importance to pain pathology. These DMLs significantly enriched pathways to involved in nociception/pain processing (Dopamine-DARPP32 Feedback in cAMP signaling, GABA Receptor Signaling, Opioid Signaling) and neuronal differentiation (e.g., Calcium Signaling, Axon Guidance Signaling, and Endocannabinoid Neuronal Synapse). Our race stratified analyses of individuals with cLBP versus PFCs revealed 2356 DMLs in NHBs and 772 DMLs in NHWs with p < 0.0001 and > 10% methylation difference. Ingenuity Pathway Analysis revealed that many pathways of significance to pain such as Corticotropin Releasing Hormone Signaling, White Adipose Tissue Browning, and GABA Receptor Signaling pathways, were more significant in NHBs than NHWs.

CONCLUSION

Even though an individual's self-identified race is a social construct, not a biological variable, racism associated with that classification affects virtually every aspect of life, including disease risk. DNAm induced alterations in stress signaling pathways may explain worse pain outcomes in NHBs.

Epigenetic signature of chronic low back pain in human T cells

Supplemental Digital Content is Available in the Text.

This study reveals sex-specific DNA methylation signatures in human T cells that discriminate chronic low back pain participants from healthy controls.

Objective:

Determine if chronic low back pain (LBP) is associated with DNA methylation signatures in human T cells that will reveal novel mechanisms and potential therapeutic targets and explore the feasibility of epigenetic diagnostic markers for pain-related pathophysiology.

Methods:

Genome-wide DNA methylation analysis of 850,000 CpG sites in women and men with chronic LBP and pain-free controls was performed. T cells were isolated (discovery cohort, n = 32) and used to identify differentially methylated CpG sites, and gene ontologies and molecular pathways were identified. A polygenic DNA methylation score for LBP was generated in both women and men. Validation was performed in an independent cohort (validation cohort, n = 63) of chronic LBP and healthy controls.

Results:

Analysis with the discovery cohort revealed a total of 2,496 and 419 differentially methylated CpGs in women and men, respectively. In women, most of these sites were hypomethylated and enriched in genes with functions in the extracellular matrix, in the immune system (ie, cytokines), or in epigenetic processes. In men, a unique chronic LBP DNA methylation signature was identified characterized by significant enrichment for genes from the major histocompatibility complex. Sex-specific polygenic DNA methylation scores were generated to estimate the pain status of each individual and confirmed in the validation cohort using pyrosequencing.

Conclusion:

This study reveals sex-specific DNA methylation signatures in human T cells that discriminates chronic LBP participants from healthy controls.

Theory-Informed Clinical Practice: How Physical Therapists Can Use Fundamental Interventions to Address Social Determinants of Health

The American Physical Therapy Association's Vision Statement for the profession is guided by principles of innovation, access, equity, and advocacy, and calls on physical therapists to stretch their influence beyond the walls of the clinic and the individuals they treat. Access and equity are problems that span multiple health care professions and entities; yet, addressing social determinants of health is a paradigm shift that clinicians need continued support to achieve. This article has 2 objectives: (1) to define the Fundamental Cause Theory and the Socioecological Model within the context of physical therapy in order to promote best clinical practice, and (2) to apply the concept of "fundamental interventions" in clinical practice to mitigate the negative impact of downstream effects of social determinants of health across levels of the Socioecological Model-individual, interpersonal, institutional, community, and societal. This theoretical lens provides the conceptual framework necessary for physical therapists to think creatively about ways to change their practice in their own contexts to impact the life of individual patients and transform the movement health of society.

IMPACT

As health care providers, physical therapists have a responsibility to make every effort to meet the needs of their patients and optimize movement health in society; yet significant structural and systemic barriers often prevent patients from reaching their fullest potential. Clinicians can no longer subscribe to a narrow scope of practice focused on individual attainment of therapy goals. This Perspective discusses Fundamental Cause Theory and the Socioecological Model theoretical frameworks that can help physical therapists develop, test, and implement functional interventions to address the needs of society as a whole.

Use of the PROMIS-10 global health in patients with chronic low back pain in outpatient physical therapy: a retrospective cohort study

Background

Although evidence-based guidelines for physical therapy for patients with chronic low back pain (cLBP) are available, selecting patient-reported outcome measures to capture complexity of health status and quality of life remains a challenge. PROMIS-10 Global Health (GH) may be used to screen for impactful health risks and enable patient-centered care. The purpose of this study was to investigate the interrelationships between PROMIS-10 GH scores and patient demographics, health status, and healthcare utilization in patients with cLBP who received physical therapy.

Methods

A retrospective review of de-identified electronic health records of patients with cLBP was performed. Data were collected for 328 patients seen from 2017 to 2020 in three physical therapy clinics. Patients were grouped into HIGH and LOW initial assessment scores on the PROMIS-10 Global Physical Health (PH) and Global Mental Health (MH) measures. Outcomes of interest were patient demographics, health status, and healthcare utilization. Mann–Whitney U and chi-square tests were used to determine differences between groups, and binary logistic regression was used to calculate odds ratios (OR) to determine predictors of PH-LOW and MH-LOW group assignments.

Results

The PH-LOW and MH-LOW groups contained larger proportions of patients who were African American, non-Hispanic, and non-commercially insured compared to PH-HIGH and MH-HIGH groups (p < .05). The PH-LOW and MH-LOW groups also had a higher Charlson comorbidity index (CCI), higher rates of diabetes and depression, and more appointment cancellations or no-shows (p < .05). African American race (OR 2.54), other race (2.01), having Medi-Cal insurance (OR 3.37), and higher CCI scores (OR 1.55) increased the likelihood of being in the PH-LOW group. African American race (OR 3.54), having Medi-Cal insurance (OR 2.19), depression (OR 3.15), kidney disease (OR 2.66), and chronic obstructive pulmonary disease (OR 1.92) all increased the likeihood of being in the MH-LOW group.

Conclusions

Our study identified groups of patients with cLBP who are more likely to have lower PH and MH scores. PROMIS-10 GH provides an opportunity to capture and identify quality of life and global health risks in patients with cLBP. Using PROMIS-10 in physical therapy practice could help identify psychosocial factors and quality of life in the population with cLBP.

Identification of DNA methylation associated enrichment pathways in adults with non-specific chronic low back pain

Chronic low back pain (cLBP) that cannot be attributable to a specific pathoanatomical change is associated with high personal and societal costs. Still, the underlying mechanism that causes and sustains such a phenotype is largely unknown. Emerging evidence suggests that epigenetic changes play a role in chronic pain conditions. Using reduced representation bisulfite sequencing (RRBS), we evaluated DNA methylation profiles of adults with non-specific cLBP (n = 50) and pain-free controls (n = 48). We identified 28,325 hypermethylated and 36,936 hypomethylated CpG sites (p < 0.05). After correcting for multiple testing, we identified 159 DMRs (q < 0.01and methylation difference > 10%), the majority of which were located in CpG island (50%) and promoter regions (48%) on the associated genes. The genes associated with the differentially methylated regions were highly enriched in biological processes that have previously been implicated in immune signaling, endochondral ossification, and G-protein coupled transmissions. Our findings support inflammatory alterations and the role of bone maturation in cLBP. This study suggests that epigenetic regulation has an important role in the pathophysiology of non-specific cLBP and a basis for future studies in biomarker development and targeted interventions.

Educational needs and challenges in axial spondyloarthritis

PURPOSE OF REVIEW

Axial spondyloarthritis (axSpA) affects 0.5-1% of the population in many regions of the world. This review summarizes the challenges in medical education around axSpA with attention to evidence around delayed diagnosis, clinician familiarity with typical axSpA features, such as inflammatory back pain and adherence to accepted management principles.

RECENT FINDINGS

Clinicians who commonly manage patients with chronic back pain or other typical axSpA features are not consistently aware of the concept of inflammatory back pain and common extra-spinal manifestations. Further, clinicians may not be familiar with the nonradiographic spectrum of axSpA. Management of patients with possible axSpA does not consistently follow principles that would establish an axSpA diagnosis, and diagnosis of axSpA remains delayed by 6-7 years on average, with evidence suggesting management disparities on the basis of sex and race in some cases. Referral recommendations have increased the probability of axSpA diagnosis up to about 40% and, may complement educational efforts in axSpA.

SUMMARY

Educational efforts in axSpA should focus on providing front-line clinicians with a better understanding of inflammatory back pain, the nonradiographic form of axSpA, and accepted principles in axSpA management.

The Relationship between Neighborhood Deprivation and Perceived Changes for Pain-Related Experiences among U.S. Patients with Chronic Low Back Pain during the COVID-19 Pandemic

OBJECTIVE

Disruptions caused by the COVID-19 pandemic could disproportionately affect the health of vulnerable populations, including patients experiencing persistent health conditions (i.e., chronic pain), along with populations living within deprived, lower socioeconomic areas. The current cross-sectional study characterized relationships between neighborhood deprivation and perceived changes in pain-related experiences during the COVID-19 pandemic (early-September to mid-October 2020) for adult patients (N = 97) with nonspecific chronic low back pain.

METHODS

We collected self-report perceived experiences from participants enrolled in an ongoing pragmatic randomized trial across medical centers within the Salt Lake City, Utah and Baltimore, Maryland metropolitans. The Area Deprivation Index (composite of 17 U.S. Census deprivation metrics) reflected neighborhood deprivation based on participants' zip codes.

RESULTS

Although those living in the neighborhoods with greater deprivation endorsed significantly poorer physical (pain severity, pain interference, physical functioning), mental (depression, anxiety), and social health during the pandemic, there were no significant differences for perceived changes in pain-related experiences (pain severity, pain interference, sleep quality) between levels of neighborhood deprivation since the onset of the pandemic. However, those in neighborhoods with greater deprivation endorsed disproportionately worse perceived changes in pain coping, social support, and mood since the pandemic.

CONCLUSIONS

The current findings offer evidence that changes in pain coping during the pandemic may be disproportionately worse for those living in deprived areas. Considering poorer pain coping may contribute to long-term consequences, the current findings suggest the need for further attention and intervention to reduce the negative affect of the pandemic for such vulnerable populations.

Race Differences in Resilience Among Older Adults with Chronic Low Back Pain

Introduction

Racial minorities are disproportionally affected by pain. Compared to non-Hispanic Whites (NHWs), non-Hispanic Blacks (NHBs) report higher pain intensity, greater pain-related disability, and higher levels of mood disturbance. While risk factors contribute to these disparities, little is known regarding how sources of resilience influence these differences, despite the growing body of research supporting the protective role of resilience in pain and disability among older adults with chronic pain. The current study examined the association between psychological resilience and pain, and the moderating role of race across these relationships in older adults with chronic low back pain (cLBP).

Methods

This is a secondary analysis of the Adaptability and Resilience in Aging Adults (ARIAA). Participants completed measures of resilience (ie, gratitude, trait resilience, emotional support), as well as a performance-based measure assessing lower-extremity function and movement-evoked pain.

Results

There were 45 participants that identified as non-Hispanic White (NHW) and 15 participants that identified as non-Hispanic Black (NHB). Race was a significant correlate of pain outcomes with NHBs reporting greater movement-evoked pain (r = 0.27) than NHWs. After controlling for relevant sociodemographic characteristics, measures of movement-evoked pain were similar across both racial groups, F (1, 48) = 0.31, p = 0.57. Moderation analyses revealed that higher levels of gratitude (b = −1.23, p = 0.02) and trait resilience (b = −10.99, p = 0.02) were protective against movement-evoked pain in NHWs. In contrast, higher levels of gratitude were associated with lower functional performance in NHBs (b = −0.13, p =0.02).

Discussion

These findings highlight racial differences in the relationship between resilience and pain-related outcomes among older adults with cLBP. Future studies should examine the potential benefits of targeted interventions that improve resilience and ameliorate pain disparities among racial minorities.

TCM nonpharmacological interventions for chronic low-back pain: A protocol for systematic review and network meta-analysis

BACKGROUND

chronic low back pain (CLBP) are common symptoms bothering people in daily life. Traditional Chinese medicine (TCM) nonpharmacological interventions are gaining an increasing popularity for CLBP. Nevertheless, the evidence of efficacy and safety of random controlled trials (RCTs) remains controversial. This study aims to evaluate the efficacy and acceptability of different TCM nonpharmacological therapies by systematic review and network meta-analysis.

METHODS

According to the strategy, The authors will retrieve a total of 7 electronic databases by September 2020, including PubMed, the Cochrane Library, EMbase, China National Knowledge Infrastructure, China Biological Medicine, Chongqing VIP, and Wan-fang databases After a series of screening, 2 researchers will use Aggregate Data Drug Information System and Stata software to analyze the data extracted from the randomized controlled trials of TCM nonpharmacological interventions for CLBP. The primary outcome will be the improvement of Pain intensity and functional status/disability and the secondary outcomes will include lobal improvement, health-related quality of life, satisfaction with treatment, and adverse events. Both classical meta-analysis and network meta-analysis will be implemented to investigate direct and indirect evidences on this topic. The quality of the evidence will be evaluated using the Grading of Recommendations Assessment, Development and Evaluation instrument.

RESULTS

This study will provide a reliable evidence for the selection of TCM nonpharmacological therapies in the treatment of CLBP.

CONCLUSION

This study will generate evidence for different TCM nonpharmacological therapies for CLBP and provide a decision-making reference for clinical research.

ETHICS AND DISSEMINATION

This study does not require ethical approval. The results will be disseminated through a peer-reviewed publication.

OSF REGISTRATION NUMBER

DOI 10.17605/OSF.IO/4H3Y9.