Racial differences in osteoarthritis pain and function: potential explanatory factors

Does Physical Activity Confound Race Differences in Osteoarthritis-Related Functional Limitation?

OBJECTIVE

This study sought to determine the extent to which physical activity confounds the relation between race and the incidence of osteoarthritis (OA)-related functional limitation.

METHODS

OA Initiative study participants with or at increased risk of knee OA who wore an accelerometer were included. Race was self-reported. Average time spent in moderate to vigorous physical activity (minutes per day) based on ActiGraph uniaxial accelerometer data was assessed. Functional limitation was based on the following: (1) inability to achieve a community walking speed (1.2 m/s) standard, (2) slow walking speed (<1.0 m/s), and (3) low physical functioning based on a Western Ontario and McMaster Universities OA Index (WOMAC) physical function score greater than 28 of 68.

RESULTS

African American (AA) participants (n = 226), compared with White participants (n = 1348), had a higher likelihood of developing functional limitation based on various measures. When adjusted for time in moderate to vigorous physical activity, the association between AA race and inability to walk a community walking speed slightly decreased (from relative risk [RR] 2.15, 95% confidence interval [95% CI] 1.64-2.81, to RR 1.99, 95% CI 1.51-2.61). Association between AA race and other measures of functional limitation mildly decreased (slow walking speed: from RR 2.06, 95% CI 1.40-3.01, to RR 1.82, 95% CI 1.25-2.63; low physical functioning: from RR 3.44, 95% CI 1.96-6.03, to RR 3.10, 95% CI 1.79-5.39). When further adjusted for demographic and other clinical variables, only the association between race and low physical functioning (WOMAC) significantly decreased and no longer met statistical significance.

CONCLUSION

Greater physical activity is unlikely to completely make up for race differences in OA-related functional limitation, and other barriers to health equity need to be addressed.

Addressing chronic pain disparities between Black and White people: a narrative review of socio-ecological determinants

A 2019 review article modified the socio-ecological model to contextualize pain disparities among different ethnoracial groups; however, the broad scope of this 2019 review necessitates deeper socio-ecological inspection of pain within each ethnoracial group. In this narrative review, we expanded upon this 2019 article by adopting inclusion criteria that would capture a more nuanced spectrum of socio-ecological findings on chronic pain within the Black community. Our search yielded a large, rich body of literature composed of 174 articles that shed further socio-ecological light on how chronic pain within the Black community is influenced by implicit bias among providers, psychological and physical comorbidities, experiences of societal and institutional racism and biomedical distrust, and the interplay among these factors. Moving forward, research and public-policy development must carefully take into account these socio-ecological factors before scaling up pre-existing solutions with questionable benefit for the chronic pain needs of Black individuals.

Taking ACTION to Reduce Pain: a Randomized Clinical Trial of a Walking-Focused, Proactive Coaching Intervention for Black Patients with Chronic Musculoskeletal Pain

BACKGROUND

Black patients in the USA are disproportionately affected by chronic pain, yet there are few interventions that address these disparities.

OBJECTIVE

To determine whether a walking-focused, proactive coaching intervention aimed at addressing contributors to racial disparities in pain would improve chronic pain outcomes among Black patients compared to usual care.

DESIGN

Randomized controlled trial with masked outcome assessment ( Clinicaltrials.gov : NCT01983228).

PARTICIPANTS

Three hundred eighty Black patients at the Atlanta VA Health Care System with moderate to severe chronic back, hip, or knee pain.

INTERVENTION

Six telephone coaching sessions over 8-14 weeks, proactively delivered, using action planning and motivational interviewing to increase walking, or usual care.

MAIN MEASURES

Primary outcome was a 30% improvement in pain-related physical functioning (Roland Morris Disability Questionnaire [RMDQ]) over 6 months among Black patients, using intention-to-treat. Secondary outcomes were improvements in pain intensity and interference, depression, anxiety, global impression of change in pain, and average daily steps.

KEY RESULTS

The intervention did not produce statistically significant effects on the primary outcome (at 6 months, 32.4% of intervention participants had 30% improvement on the RMDQ vs. 24.7% of patients in usual care; aOR=1.61, 95% CI, 0.94 to 2.77), nor on other secondary outcomes assessed at 6 months, with the exception that intervention participants reported more favorable changes in pain relative to usual care (mean difference=-0.54, 95% CI, -0.85 to -0.23). Intervention participants also experienced a significant reduction in pain intensity and pain interference over 3 months (mean difference=-0.55, 95% CI, -0.88 to -0.22).

CONCLUSIONS

A novel intervention to improve chronic pain among Black patients did not produce statistically significant improvements on the primary outcome relative to usual care. More intensive efforts are likely required among this population, many of whom were economically disadvantaged and had mental health comorbidities and physical limitations.

TRIAL REGISTRATION

Clinicaltrials.gov Identifier: NCT01983228.

Psychosocial Predictors of Chronic Musculoskeletal Pain Outcomes and their Contextual Determinants Among Black Individuals: A Narrative Review

Black communities are disproportionally affected by Chronic Musculoskeletal Pain (CMP), but little is known about the psychological predictors of CMP outcomes and their contextual determinants among Black individuals. To address this gap, we conducted a narrative review of extant literature to (1) report the major conceptual models mentioned in prior work explaining the link between contextual determinants and psychological responses to pain among Black individuals with CMP; and (2) describe psychological factors related to CMP outcomes in this population that are highlighted in the literature. We searched 4 databases (APA PsycNet, PubMed/MEDLINE, Scopus, and Google Scholar) using the following search terms: musculoskeletal pain, chronic pain, mental health, psychological, coping, health disparities, contextual factors, conceptual models, psychosocial, Black, African American, pain, disability, and outcomes. We illustrate 3 relevant conceptual models - socioecological, cumulative stress, and biopsychosocial - related to contextual determinants and several psychological factors that influence CMP outcomes among Black individuals: (1) disproportionate burden of mental health and psychiatric diagnoses, (2) distinct coping strategies, (3) pain-related perceived injustice and perceived racial/ethnic discrimination, and (4) preferences and expectations related to seeking and receiving pain care. The detailed clinical and research implications could serve as a blueprint for the providers and clinical researchers to address health disparities and improve care for Black individuals with CMP. PERSPECTIVE: This narrative review illustrates conceptual models explaining the link between contextual determinants and psychological responses to pain among Black individuals with chronic musculoskeletal pain. We discuss 3 relevant conceptual models - socioecological, cumulative stress, biopsychosocial -, and 4 psychological factors: disproportionate burden of mental health, distinct coping strategies, perceived injustice/discrimination, preferences/expectations.

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.

[Noninvasive Treatments for Acute and Chronic Back Pain]

Noninvasive Treatments for Acute and Chronic Back Pain Abstract. The therapy of back pain - especially the medication with opioids - can be challenging for the treating physician. Specific back pain can often be diagnosed by imaging and successfully treated by surgery or medication. In contrast, nonspecific back pain can be worsened by inappropriate imaging, questionable surgical indications and uncontrolled drug use. For the therapy of nonspecific back pain, maintaining daily activity and exercise therapy is central. Opioids are effective drugs for short-term use. However, long-term use often leads to opioid-induced hyperalgesia and hormonal dysfunction with decreased quality of life and libido. Furthermore, opioids can lead to abuse and addiction. After an ineffective treatment with non-opioids, opioids may be given for a limited time period (if possible shorter than four weeks) according to international guidelines.

Associations of pain catastrophizing with pain-related brain structure in individuals with or at risk for knee osteoarthritis: Sociodemographic considerations

Compelling evidence exists that non-Hispanic blacks (NHB) engage in pain catastrophizing (negatively evaluate one's ability to cope with pain) more often than non-Hispanic whites (NHW). Functional neuroimaging studies revealed that individuals with high levels of trait pain catastrophizing show increased cerebral responses to pain in several pain-related brain regions (e.g., insula, primary somatosensory cortex [S1]), but associations between brain structure and catastrophizing remain largely unexplored. The current investigation was conducted at the University of Florida and the University of Alabama at Birmingham. Participants were 129 community-dwelling adults with or at risk of knee osteoarthritis (OA). Participants completed the pain catastrophizing subscale of the Coping Strategies Questionnaire-Revised and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain intensity subscale. Magnetic Resonance Imaging data were obtained. MANOVA and Chi-Square analyses assessed sociodemographic/clinical differences stratified by ethnicity/race. Multivariate regression analyses with insula and somatosensory cortical thickness entered as dependent variables with catastrophizing and the interaction between catastrophizing and ethnicity/race as the independent variables. Covariates include education, body mass index, study site, and WOMAC pain (ethnicity/race was an additional covariate in non-stratified analyses). There were significant interactions between ethnicity/race, pain catastrophizing, and brain structure. Higher pain catastrophizing was associated with thinner S1 bilaterally (ps < .05) in NHW, but not NHB participants with or at risk for knee OA. These results suggest that pain catastrophizing might have differing effects on pain-related central pathways and may contribute to ethnic/race group differences in individuals with or at risk for knee OA.

Quantifying Mediators of Racial Disparities in Knee Osteoarthritis Outcome Scores: A Cross-Sectional Analysis

Studies on symptomatic osteoarthritis suggest that Black patients report worse pain and symptoms compared with White patients with osteoarthritis. In this study, we aimed to quantify the relationship among variables such as overall health and socioeconomic status that may contribute to disparities in patient-reported outcomes.

Applying the NIA Health Disparities Research Framework to Identify Needs and Opportunities in Chronic Musculoskeletal Pain Research

Disparities in the experience of chronic musculoskeletal pain in the United States stem from a confluence of a broad array of factors. Organized within the National Institute on Aging Health Disparity Research Framework, a literature review was completed to evaluate what is known and what is needed to move chronic musculoskeletal pain research forward specific to disproportionately affected populations. Peer-reviewed studies published in English, on human adults, from 2000 to 2019, and conducted in the United States were extracted from PubMed and Web of Science. Articles were reviewed for key words that focused on underrepresented ethnic/race groups with chronic musculoskeletal pain applying health factor terms identified in the NIAHealth Disparity Research Framework four levels of analysis: 1) environmental, 2) sociocultural, 3) behavioral, and 4) biological. A total of 52 articles met inclusion criteria. There were limited publications specific to underrepresented ethnic/race groups with chronic musculoskeletal pain across all levels with particular research gaps under sociocultural and biological categories. Current limitations in evidence may be supplemented by a foundation of findings specific to the broader topic of "chronic pain" which provides guidance for future investigations. Study designs including a focus on protective factors and multiple levels of analyses would be particularly meritorious. PERSPECTIVE: Chronic musculoskeletal pain unequally burdens underrepresented ethnic/race groups. In order to move research forward and to systematically investigate the complex array of factors contributing toward health disparities, an organized approach is necessary. Applying the NIA Health Disparities Research Framework, an overview of the current state of evidence specific to chronic musculoskeletal pain and underrepresented ethnic/race groups is provided with future directions identified.

Cumulative Disadvantage and Disparities in Depression and Pain Among Veterans With Osteoarthritis: The Role of Perceived Discrimination

OBJECTIVE

Perceived discrimination is associated with chronic pain and depression and contributes to racial health disparities. In a cohort of older adult veterans with osteoarthritis (OA), our objective was to examine how membership in multiple socially disadvantaged groups (cumulative disadvantage) was associated with perceived discrimination, pain, and depression. We also tested whether perceived discrimination mediated the association of cumulative disadvantage with depression and pain.

METHODS

We analyzed baseline data from 270 African American veterans and 247 White veterans enrolled in a randomized controlled trial testing a psychological intervention for chronic pain at 2 Department of Veterans Affairs medical centers. Participants were age ≥50 years and self-reported symptomatic knee OA. Measures included the Everyday Discrimination Scale, the Patient Health Questionnaire Depression Scale, the Western Ontario and McMaster Universities Osteoarthritis Index pain subscale, and demographic variables. Cumulative disadvantage was defined as the number of socially disadvantaged groups to which each participant belonged (i.e., self-reported female sex, African American race, annual income of <$20,000, and/or unemployed due to disability). We used linear regression models and Sobel's test of mediation to examine hypotheses.

RESULTS

The mean ± SD number of social disadvantages was 1.3 ± 1.0. Cumulative disadvantage was significantly associated with higher perceived discrimination, pain, and depression (P < 0.001 for all). Perceived discrimination significantly mediated the association between cumulative disadvantage and depression symptoms (Z = 3.75, P < 0.001) as well as pain severity (Z = 2.24, P = 0.025).

CONCLUSION

Perceived discrimination is an important psychosocial stressor that contributes to worsening OA-related mental and physical health outcomes, with greater effects among those from multiple socially disadvantaged groups.

An algorithmic approach to reducing unexplained pain disparities in underserved populations

Underserved populations experience higher levels of pain. These disparities persist even after controlling for the objective severity of diseases like osteoarthritis, as graded by human physicians using medical images, raising the possibility that underserved patients' pain stems from factors external to the knee, such as stress. Here we use a deep learning approach to measure the severity of osteoarthritis, by using knee X-rays to predict patients' experienced pain. We show that this approach dramatically reduces unexplained racial disparities in pain. Relative to standard measures of severity graded by radiologists, which accounted for only 9% (95% confidence interval (CI), 3-16%) of racial disparities in pain, algorithmic predictions accounted for 43% of disparities, or 4.7× more (95% CI, 3.2-11.8×), with similar results for lower-income and less-educated patients. This suggests that much of underserved patients' pain stems from factors within the knee not reflected in standard radiographic measures of severity. We show that the algorithm's ability to reduce unexplained disparities is rooted in the racial and socioeconomic diversity of the training set. Because algorithmic severity measures better capture underserved patients' pain, and severity measures influence treatment decisions, algorithmic predictions could potentially redress disparities in access to treatments like arthroplasty.

Racial/Ethnic, Socioeconomic, and Geographic Disparities in the Epidemiology of Knee and Hip Osteoarthritis

It is estimated that 32.5 million US adults have clinical osteoarthritis (OA), with the most common sites being knee and hip. OA is associated with substantial individual and societal costs. Race/ethnicity, socioeconomic status (SES), and geographic variations in the prevalence of knee and hip OA are well established around the world. In addition, clinical outcomes associated with hip and knee OA differ according to race/ethnicity, SES, and geography. This variation is likely multifactorial and may also reflect country-specific differences in health care systems. The interplay between different factors, such as geography, SES, and race/ethnicity, is difficult to study.

Racial Differences in Performance-Based Function and Potential Explanatory Factors Among Individuals With Knee Osteoarthritis

OBJECTIVE

In individuals with knee osteoarthritis (OA), self-reported physical function is poorer in African Americans than in whites, but whether this difference holds true for objective assessments is unclear. The purpose of this study was to examine racial differences in performance-based physical function as well as potential underlying factors contributing to these racial differences.

METHODS

Participants with knee OA from a randomized controlled trial completed the 2-minute step test (2MST), timed-up-and-go (TUG), and 30-second chair stand (30s-CST) at baseline. Race differences in performance-based function were assessed by logistic regression. Separate models were adjusted for sets of demographic, socioeconomic, psychological health, and physical health variables.

RESULTS

In individuals with knee OA (n = 322; 72% women, 22% African American, mean ± SD age 66 ± 11 years, mean ± SD body mass index 31 ± 8 kg/m2 ), African Americans (versus whites) had greater unadjusted odds of poorer function (30s-CST odds ratio [OR] 2.79 [95% confidence interval (95% CI) 1.65-4.72], 2MST OR 2.37 [95% CI 1.40-4.03], and TUG OR 3.71 [95% CI 2.16-6.36]). Relationships were maintained when adjusted for demographic and psychological health covariates, but they were either partially attenuated or nonsignificant when adjusted for physical health and socioeconomic covariates.

CONCLUSION

African American adults with knee OA had poorer unadjusted performance-based function than whites. Physical health and socioeconomic characteristics diminished these differences, emphasizing the fact that these factors may be important to consider in mitigating racial disparities in function.

Acceptability of telephone-based pain coping skills training among African Americans with osteoarthritis enrolled in a randomized controlled trial: a mixed methods analysis

BACKGROUND

Osteoarthritis (OA) disproportionately impacts African Americans compared to Caucasians, including greater pain severity. The Pain Coping Skills Training for African Americans with Osteoarthritis (STAART) study examined a culturally enhanced Pain Coping Skills Training (CST) program among African Americans with OA. This mixed methods study evaluated the acceptability of the Pain CST program among STAART participants.

METHODS

STAART was a randomized controlled trial evaluating the effectiveness of an 11-session, telephone-based pain CST program, compared to a usual care control group. Participants were from the University of North Carolina and Durham Veterans Affairs Healthcare Systems. The present analyses included 93 participants in the CST group who completed a questionnaire about experiences with the program. Descriptive statistics of the questionnaire responses were calculated using SAS software. Thematic analysis was applied to open-response data using Dedoose software.

RESULTS

Participants' mean rating of overall helpfulness of the pain CST program for managing arthritis symptoms was 8.0 (SD = 2.2) on a scale of 0-10. A majority of participants reported the program made a positive difference in their experience with arthritis (83.1%). Mean ratings of helpfulness of the specific skills ranged from 7.7 to 8.8 (all scales 0-10). Qualitative analysis of the open-response data identified four prominent themes: Improved Pain Coping, Mood and Emotional Benefits, Improved Physical Functioning, and experiences related to Intervention Delivery.

CONCLUSIONS

The high ratings of helpfulness demonstrate acceptability of this culturally enhanced pain CST program by African Americans with OA. Increasing access to cognitive-behavioral therapy-based programs may be a promising strategy to address racial disparities in OA-related pain and associated outcomes.

TRIAL REGISTRATION

NCT02560922 , registered September 25, 2015.

Patterns and Correlates of Self-Management Strategies for Osteoarthritis-Related Pain Among Older Non-Hispanic Black and Non-Hispanic White Adults

OBJECTIVE

Knee osteoarthritis (OA) is a leading source of pain and disability among older adults. Self-management (SM) strategies are recommended to manage OA symptoms. Sociodemographic and clinical characteristics, along with other factors, may influence SM utilization rate. This study sought to examine the prevalence and correlates of SM use for pain among non-Hispanic Black patients (NHB) and non-Hispanic White patients (NHW) older adults with or at risk for knee OA.

METHODS

A secondary data analysis was conducted on the Understanding Pain and Limitations in Osteoarthritic Disease multisite observational study, which included NHB (n = 104) and NHW (n = 98) community-dwelling older adults with or at risk for knee OA. Participants completed measures of sociodemographics, pain SM use, coping, and clinical and experimental pain.

RESULTS

Clinical and experimental pain were significantly greater among NHBs compared to NHWs. There were no significant differences in use of total SM by ethnicity/race. Interestingly, multiple linear regression revealed that clinical and experimental pain indices, as well as coping, number of pain sites, age, and sex were differentially associated with total SM use between NHBs and NHWs. There were significant ethnicity/race by type of pain management interaction effects for pain measures.

CONCLUSION

SM is common among older adults with or at risk for knee OA pain, and the prevalence of SM does not differ by ethnicity/race, but many guideline-recommended interventions for OA are underutilized. Importantly, different factors were associated with the use of SM, highlighting distinct biopsychosocial mechanisms contributing to SM use in NHBs and NHWs.

Pain coping skills training for African Americans with osteoarthritis: results of a randomized controlled trial

African Americans bear a disproportionate burden of osteoarthritis (OA), but they have been underrepresented in trials of behavioral interventions for pain. This trial examined a culturally tailored pain coping skills training (CST) program, compared to a wait list control group, among 248 African Americans with knee or hip OA. The pain CST program involved 11 telephone-based sessions over 3 months. Outcomes were assessed at baseline, 3 months (primary), and 9 months, and included the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain subscale (primary outcome), WOMAC total score and function subscale, PROMIS Pain Interference, Short-Form 12 Mental and Physical Composite Subscales, Coping Strategies Questionnaire-Total Coping Attempts, Pain Catastrophizing Scale, Patient Health Questionnaire-8, Arthritis Self-Efficacy Scale, and Patient Global Impression of Arthritis Symptom Change. Linear mixed models were fit for all outcomes. There were no significant between-group differences in WOMAC pain score at 3 months (-0.63 [95% confidence interval -1.45, 0.18]; P = 0.128) or 9 months (-0.84 [95% confidence interval -1.73, 0.06]; P = 0.068). Among secondary outcomes, at 3 months, there were significant differences, in favor of the CST group, for Coping Strategies Questionnaire Total Coping Attempts, Pain Catastrophizing Scale, Arthritis Self-Efficacy, and Patient Global Impression of Arthritis Symptom Change (P < 0.01). Coping Strategies Questionnaire Total Coping Attempts, Arthritis Self-Efficacy, and Patient Global Assessment Change were also significantly improved at 9 months in the CST group, compared with wait list (P < 0.01). The culturally tailored pain CST program did not significantly reduce pain severity but did improve key measures of pain coping and perceived ability to manage pain among African Americans with OA.

Racial Differences in Pain and Function Following Knee Arthroplasty: A Secondary Analysis From a Multicenter Randomized Clinical Trial

OBJECTIVE

The assessment of racial differences in pain and function outcome following knee arthroplasty (KA) has received little attention despite very substantial literature exploring a variety of other prognostic factors. The present study was undertaken to determine whether race was associated with KA outcome after accounting for potential confounding factors.

METHODS

We conducted a secondary analysis of a randomized clinical trial of 384 participants with moderate-to-high pain catastrophizing who underwent KA. Preoperative measures included race/ethnicity status as well as a variety of potential confounders, including socioeconomic status, comorbidity, and bodily pain. Outcome measures were Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain and function scales as well as performance measures. Linear mixed-effects models compared outcomes over a 1-year follow-up period for African American versus non-African American participants.

RESULTS

WOMAC pain scores differences for African American versus non-African American participants averaged ~2 points in unadjusted analyses and 1-1.5 points in adjusted analyses. In adjusted analyses, follow-up WOMAC function scores differed by 6 points for African Americans compared to non-African Americans (P = 0.002).

CONCLUSION

African Americans generally had worse pain, function, and performance prior to KA and worse scores after surgery, but differences were small and attenuated by ~25-50% after adjustment for potential confounding. Only WOMAC function scores showed clinically important postsurgical differences in adjusted analyses. Clinicians should be aware that after adjustment for potential confounders, African Americans have approximately equivalent outcomes compared to others, with the exception of WOMAC function score.

Platelet-rich plasma versus hyaluronic acid in the treatment of knee osteoarthritis: A meta-analysis

BACKGROUND

This meta-analysis focuses on the controversial efficacy and safety of platelet-rich plasma (PRP) as compared with hyaluronic acid (HA) in the clinical treatment of knee osteoarthritis. We have attempted to provide an evidence-based medicine protocol for the conservative treatment of knee osteoarthritis. In addition, we included the latest relevant literature in this meta-analysis, and a staging study was conducted to compare the therapeutic effects of PRP and HA for knee osteoarthritis over different time periods.

METHODS

An online computer search with "platelet-rich plasma" and "knee osteoarthritis" as search terms was conducted in the PubMed, EMBASE, and Cochrane Library databases. We conducted a quality assessment of the retrieved literature and extracted the following indicators: visual analog scale (VAS) score, subjective International Knee Documentation Committee (IKDC) score, Western Ontario and McMaster Universities (WOMAC) score, Knee Injury and Osteoarthritis Outcome Score (KOOS), and adverse events. RevMan5.3 software was used to determine the effect sizes, and indicators were compared across studies at three different time points from the administration of treatment.

RESULTS

A total of 14 randomized controlled trials (RCTs) involving 1350 patients were included. Long-term VAS, IKDC, WOMAC-Pain, WOMAC-Stiffness, WOMAC-Physical Function, and WOMAC-Total scores at each time point were higher in the PRP group than in the HA group. There were no significant differences in the remaining indicators between the two groups.

CONCLUSION

Compared with HA, PRP offers obvious advantages in the conservative treatment of knee osteoarthritis. Treatment with PRP can reduce long-term pain and improve knee joint function with no additional risks. Therefore, PRP can be widely used for the conservative treatment of knee osteoarthritis.

At the Intersection of Ethnicity/Race and Poverty: Knee Pain and Physical Function

BACKGROUND

Knee osteoarthritis (OA) disproportionately affects racial and ethnic minorities. Non-Hispanic Blacks (NHB) report a higher prevalence and severity of knee OA symptoms than their non-Hispanic White (NHW) counterparts. The role of poverty in explaining this disparity remains unclear.

OBJECTIVE

The overall aim of this cross-sectional study was to determine whether ethnic/racial differences in knee pain and physical function varied according to poverty status.

DESIGN

NHB and NHW adults with or at risk of knee OA self-reported sociodemographic information, and completed the Western Ontario & McMaster Universities Osteoarthritis Index (WOMAC) and the Short Physical Performance Battery (SPPB). Annual income was adjusted for number of household occupants to determine poverty status (i.e., living above versus below poverty line).

RESULTS

Findings revealed 120 individuals living above the poverty line (49% NHB, 77% NHW) and 71 individuals living below the poverty line (51% NHB, 23% NHW). Adjusted multivariable models revealed significant ethnic/race by poverty status interactions for knee pain (p = 0.036) and physical function (p = 0.032) on the WOMAC, as well as physical function on the SPPB (p = 0.042). Post hoc contrasts generally revealed that NHW adults living above the poverty line experienced the least severe knee pain and best physical function, while NHB adults living below the poverty line experienced the most severe knee pain and poorest physical function.

CONCLUSIONS

Results of the present study add to the literature by emphasizing the importance of considering poverty and/or other indicators of socioeconomic status in studies examining ethnic/racial disparities in pain and physical function.

Arthritis self-efficacy beliefs and functioning among osteoarthritis and rheumatoid arthritis patients: a meta-analytic review

Objectives

The Arthritis Self-Efficacy Scale (ASES) is a widely used self-report measure of beliefs reflecting confidence in one’s capacity to function despite pain and control pain or other symptoms of arthritis. Despite evidence linking higher ASES scores to lower levels of impairment, pain and emotional distress, numerous modest, non-significant associations have also been observed. In this meta-analysis, we evaluated overall associations between ASES scores and adjustment in RA and OA samples as well as potential moderators that may explain the heterogeneity in these associations.

Method

Data from 48 samples that met all 10 inclusion criteria (N = 9222 patients) were subject to analyses.

Results

ASES scores had significant medium average effect sizes with functional impairment, pain severity and emotional distress but substantial heterogeneity was evident for each association. ASES–impairment associations were moderated by the diagnosis, ASES version and ASES subscale content: significantly larger effect sizes were found for studies that included RA patients, used the original 20-item ASES and assessed subscale content reflecting the pursuit of daily activities despite pain (i.e. functional self-efficacy) than for studies based exclusively on OA patients, the eight-item ASES and ASES pain control and other symptom subscales. Relations of ASES scores with pain severity and emotional distress were moderated by ASES version and subscale content, respectively.

Conclusion

The ASES has significant overall associations with key areas of functioning. Moderator analyses of the measure provide empirically grounded suggestions for optimal use of the ASES within OA and RA patient samples.

Racial and ethnic differences in the experience and treatment of noncancer pain

The burden of pain is unequal across racial and ethnic groups. In addition to racial and ethnic differences in the experience of pain, there are racial and ethnic disparities in the assessment and treatment of pain. In this article, we provide a nonexhaustive review of the biopsychosocial mechanistic factors contributing to racial and ethnic differences in both the experience and treatment of pain. Using a modified version of the Socioecological Model, we focus on patient-, provider- and system-level factors including coping, perceived bias and discrimination, patient preferences, expectations, patient/provider communication, treatment outcomes and healthcare access. In conclusion, we provide psychosocial factors influencing racial and ethnic differences in pain and highlight future research targets and possible solutions to reduce these disparities.

Racial-Ethnic Differences in Osteoarthritis Pain and Disability: A Meta-Analysis

Osteoarthritis (OA), a leading cause of disability and pain, affects 32.5 million Americans, producing tremendous economic burden. Although some findings suggest that racial/ethnic minorities experience increased OA pain severity, other studies have shown conflicting results. This meta-analysis examined differences in clinical pain severity between African Americans (AAs) and non-Hispanic whites with OA. Articles were initially identified between October 1 and 5, 2016, and updated May 30, 2018, using PubMed, Web of Science, PsycINFO, and the Cochrane Library Database. Eligibility included English-language peer-reviewed articles comparing clinical pain severity in adult black/AA and non-Hispanic white/Caucasian patients with OA. Nonduplicate article abstracts (N = 1,194) were screened by 4 reviewers, 224 articles underwent full-text review, and 61 articles reported effect sizes of pain severity stratified by race. Forest plots of the standard mean difference showed higher pain severity in AAs for studies using the Western Ontario and McMasters Universities Osteoarthritis Index (0.57; 95% confidence interval [CI], 0.54-0.61) and non-Western Ontario and McMasters Universities Osteoarthritis Index studies (0.35, 95% CI, 0.23-0.47). AAs also showed higher self-reported disability (0.38, 95% CI, 0.22-0.54) and poorer performance testing (-0.58, 95% CI, -0.72 to -0.44). Clinical pain severity and disability in OA is higher among AAs and future studies should explore the reasons for these differences to improve pain management. PERSPECTIVE: This meta-analysis shows that differences exist in clinical pain severity, functional limitations, and poor performance between AAs and non-Hispanic whites with OA. This research may lead to a better understanding of racial/ethnic differences in OA-related pain.

Pain coping skills training for African Americans with osteoarthritis study: baseline participant characteristics and comparison to prior studies

Background

The Pain Coping Skills Training for African Americans with OsteoaRTthritis (STAART) trial is examining the effectiveness of a culturally enhanced pain coping skills training (CST) program for African Americans with osteoarthritis (OA). This disparities-focused trial aimed to reach a population with greater symptom severity and risk factors for poor pain-related outcomes than previous studies. This paper compares characteristics of STAART participants with prior studies of CST or cognitive behavioral therapy (CBT)-informed training in pain coping strategies for OA.

Methods

A literature search identified 10 prior trials of pain CST or CBT-informed pain coping training among individuals with OA. We descriptively compared characteristics of STAART participants with other studies, in 3 domains of the National Institutes of Minority Health and Health Disparities’ Research Framework: Sociocultural Environment (e.g., age, education, marital status), Biological Vulnerability and Mechanisms (e.g, pain and function, body mass index), and Health Behaviors and Coping (e.g., pain catastrophizing). Means and standard deviations (SDs) or proportions were calculated for STAART participants and extracted from published manuscripts for comparator studies.

Results

The mean age of STAART participants, 59 years (SD = 10.3), was lower than 9 of 10 comparator studies; the proportion of individuals with some education beyond high school, 75%, was comparable to comparator studies (61–86%); and the proportion of individuals who are married or living with a partner, 42%, was lower than comparator studies (62–66%). Comparator studies had less than about 1/3 African American participants. Mean scores on the Western Ontario and McMaster Universities Osteoarthritis Index pain and function scales were higher (worse) for STAART participants than for other studies, and mean body mass index of STAART participants, 35.2 kg/m² (SD = 8.2), was higher than all other studies (30–34 kg/m²). STAART participants’ mean score on the Pain Catastrophizing scale, 19.8 (SD = 12.3), was higher (worse) than other studies reporting this measure (7–17).

Conclusions

Compared with prior studies with predominantly white samples, STAART participants have worse pain and function and more risk factors for negative pain-related outcomes across several domains. Given STAART participants’ high mean pain catastrophizing scores, this sample may particularly benefit from the CST intervention approach.

Trial registration

NCT02560922

Electronic supplementary material

The online version of this article (10.1186/s12891-018-2249-6) contains supplementary material, which is available to authorized users.

Effect of a Positive Psychological Intervention on Pain and Functional Difficulty Among Adults With Osteoarthritis: A Randomized Clinical Trial

IMPORTANCE

Positive psychological interventions for improving health have received increasing attention recently. Evidence on the impact of such interventions on pain, and racial disparities in pain, is limited.

OBJECTIVE

To assess the effects of a positive psychological intervention on pain and functional difficulty in veterans with knee osteoarthritis.

DESIGN, SETTING, AND PARTICIPANTS

The Staying Positive With Arthritis Study is a large, double-blinded randomized clinical trial powered to detect race differences in self-reported pain in response to a positive psychological intervention compared with a neutral control intervention. Data were collected from 2 urban Veterans Affairs medical centers. Participants included non-Hispanic white and non-Hispanic African American patients aged 50 years or older with a diagnosis of osteoarthritis. Mailings were sent to 5111 patients meeting these criteria, of whom 839 were fully screened, 488 were eligible, and 360 were randomized. Enrollment lasted from July 8, 2015, to February 1, 2017, with follow-up through September 6, 2017.

INTERVENTIONS

The intervention comprised a 6-week series of evidence-based activities to build positive psychological skills (eg, gratitude and kindness). The control program comprised similarly structured neutral activities. Programs were delivered via workbook and weekly telephone calls with interventionists.

MAIN OUTCOMES AND MEASURES

The primary outcomes were self-reported pain and functional difficulty measured using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC; range 0-100). Secondary outcomes included affect balance and life satisfaction.

RESULTS

The sample included 180 non-Hispanic white patients and 180 non-Hispanic African American patients (mean [SD] age, 64.2 [8.8] years; 76.4% were male). Mean (SD) baseline scores for WOMAC pain and functional difficulty were 48.8 (17.6) and 46.8 (18.1), respectively. Although both decreased significantly over time (pain: χ23 = 49.50, P < .001; functional difficulty: χ23 = 22.11, P < .001), differences were small and did not vary by treatment group or race. Exploratory analyses suggested that the intervention had counterintuitive effects on secondary outcomes.

CONCLUSIONS AND RELEVANCE

The results of this randomized clinical trial do not support the use of positive psychological interventions as a stand-alone treatment for pain among white or African American veterans with knee osteoarthritis. Adaptations are needed to identify intervention components that resonate with this population, and the additive effect of incorporating positive psychological interventions into more comprehensive pain treatment regimens should be considered.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02223858.

Ethnicity, Cortisol, and Experimental Pain Responses Among Persons With Symptomatic Knee Osteoarthritis

OBJECTIVES

Although several factors are known to contribute to ethnic differences in pain, relatively little attention has been devoted to physiological factors. Our first aim was to examine the relationship between cortisol and pain responses during a cold-pressor task (CPT) among African American (AA) and non-Hispanic White (NHW) adults with knee osteoarthritis (OA). Our second aim was to assess the relationship between perceived racial discrimination and cortisol among AA participants.

MATERIALS AND METHODS

Participants were 91 (56 AA; 35 NHW) community-dwelling adults between the ages of 45 to 85 with knee OA based upon the American College of Rheumatology clinical criteria. Plasma cortisol was measured at 3 timepoints: (1) baseline, (2) before the CPT, and (3) 20 minutes following the CPT. Perceived racial discrimination was measured by the Experiences of Discrimination scale.

RESULTS

Using linear regression, we found a significant interaction between ethnicity and cortisol before the CPT with pain intensity ratings (β=-0.26; P=0.02). Analysis of simple slopes revealed that cortisol concentrations were negatively associated with pain intensity ratings in NHW participants (β=-0.54; P=0.001), but not in AA participants (β=-0.15; P=0.26). Perceived racial discrimination was not related to cortisol concentrations or pain ratings.

DISCUSSION

Consistent with previous findings in young healthy adults, cold-pressor pain responses are related to pre-CPT cortisol concentrations in NHW persons with knee OA but not in their AA counterparts. Additional studies are required to better understand this finding.

Natural history of pain and disability among African-Americans and Whites with or at risk for knee osteoarthritis: A longitudinal study

OBJECTIVE

Compare knee pain and disability between African Americans (AAs) and Whites (WHs), with or at risk of knee osteoarthritis (KOA), over 9 years, and evaluate racial disparities in KOA-related symptoms across socioeconomic and clinical characteristics.

DESIGN

Osteoarthritis Initiative (OAI) participants were evaluated annually over 9 years for pain and disability, assessed by the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and a numerical rating scale (NRS) for knee pain severity. Mean annual WOMAC pain, NRS pain, and WOMAC disability levels were estimated by race using mixed effects models, adjusted for age, sex, education, marital status, body mass index (BMI), depression, and baseline Kellgren-Lawrence grade score. Race-specific mean WOMAC pain scores were also estimated in analyses stratified by socioeconomic and clinical characteristics.

RESULTS

AAs reported worse mean WOMAC pain compared to WHs at baseline (3.69 vs 2.20; P ≤ 0.0001) and over 9 years of follow-up, with similar disparities reflected in NRS pain severity and WOMAC disability. Radiographic severity did not account for the differences in pain and disability, as substantial and significant racial disparities were observed after stratification by Kellgren-Lawrence grade. Depression and low income exacerbated differences in WOMAC pain between AAs and WHs by a substantial and significant magnitude.

CONCLUSIONS

Over 9 years of follow-up, AAs reported persistently greater KOA symptoms than WHs. Socioeconomically and clinically disadvantaged AAs reported the most pronounced disparities in pain and disability.

Pain and Function in Home Care: A Need for Treatment Tailoring to Reduce Disparities?

OBJECTIVES

To describe racial/ethnic group differences in pain presentation and the prevalence of psychosocial factors among patients admitted to home health care, and to determine the extent of racial/ethnic group differences in the association of psychosocial factors with pain intensity and pain-related disability.

METHODS

We analyzed cross-sectional data on 588 patients with activity-limiting pain admitted to home care for physical therapy. Three psychosocial factors were assessed: depressive symptoms, pain self-efficacy, and health literacy. Statistical methods included estimation of general linear models of pain intensity and pain-related disability.

RESULTS

Hispanics and non-Hispanic blacks report a greater number of pain sites, worse pain intensity, and higher levels of pain-related disability than non-Hispanic whites and others. Racial/ethnic minority group patients also have a higher prevalence of adverse psychosocial factors than others, with evidence that race/ethnicity interacts with pain self-efficacy and depressive symptoms in their association with mean pain intensity and pain-related disability, respectively.

DISCUSSION

The substantial racial/ethnic difference in the psychosocial profiles of older adults with activity-limiting pain highlights the importance of screening for these modifiable risk factors and tailoring interventions accordingly. Direct attention to the psychosocial needs of patients could help to address racial/ethnic disparities in pain outcomes.

Rationale and design of the Staying Positive with Arthritis (SPA) Study: A randomized controlled trial testing the impact of a positive psychology intervention on racial disparities in pain

Knee osteoarthritis is a painful, disabling condition that disproportionately affects African Americans. Existing arthritis treatments yield small to moderate improvements in pain and have not been effective at reducing racial disparities in the management of pain. The biopsychosocial model of pain and evidence from the positive psychology literature suggest that increasing positive psychological skills (e.g., gratitude, kindness) could improve pain and functioning and reduce disparities in osteoarthritis pain management. Activities to cultivate positive psychological skills have been developed and validated; however, they have not been tested in patients with osteoarthritis, their effects on racial differences in health outcomes have not been examined, and evidence of their effects on health outcomes in patients with other chronic illnesses is of limited quality. In this article we describe the rationale and design of Staying Positive with Arthritis (SPA) study, a randomized controlled trial in which 180 African American and 180 White primary care patients with chronic pain from knee osteoarthritis will be randomized to a 6-week program of either positive skill-building activities or neutral control activities. The primary outcomes will be self-reported pain and functioning as measured by the WOMAC Osteoarthritis Index. We will assess these primary outcomes and potential, exploratory psychosocial mediating variables at an in-person baseline visit and by telephone at 1, 3, and 6months following completion of the assigned program. If effective, the SPA program would be a novel, theoretically-informed psychosocial intervention to improve quality and equity of care in the management of chronic pain from osteoarthritis.

Racial and Ethnic Differences in Total Knee Arthroplasty in the Veterans Affairs Health Care System, 2001-2013

OBJECTIVE

To examine black-white and Hispanic-white differences in total knee arthroplasty from 2001 to 2013 in a large cohort of patients diagnosed with osteoarthritis (OA) in the Veterans Affairs (VA) health care system.

METHODS

Data were from the VA Musculoskeletal Disorders cohort, which includes data from electronic health records of more than 5.4 million veterans with musculoskeletal disorders diagnoses. We included white (non-Hispanic), black (non-Hispanic), and Hispanic (any race) veterans, age ≥50 years, with an OA diagnosis from 2001-2011 (n = 539,841). Veterans were followed from their first OA diagnosis until September 30, 2013. As a proxy for increased clinical severity, analyses were also conducted for a subsample restricted to those who saw an orthopedic or rheumatology specialist (n = 148,844). We used Cox proportional hazards regression to examine racial and ethnic differences in total knee arthroplasty by year of OA diagnosis, adjusting for age, sex, body mass index, physical and mental diagnoses, and pain intensity scores.

RESULTS

We identified 12,087 total knee arthroplasty procedures in a sample of 473,170 white, 50,172 black, and 16,499 Hispanic veterans. In adjusted models examining black-white and Hispanic-white differences by year of OA diagnosis, total knee arthroplasty rates were lower for black than for white veterans diagnosed in all but 2 years. There were no Hispanic-white differences regardless of when diagnosis occurred. These patterns held in the specialty clinic subsample.

CONCLUSION

Black-white differences in total knee arthroplasty appear to be persistent in the VA, even after controlling for potential clinical confounders.

Pain coping skills training for African Americans with osteoarthritis (STAART): study protocol of a randomized controlled trial

BACKGROUND

African Americans bear a disproportionate burden of osteoarthritis (OA), with higher prevalence rates, more severe pain, and more functional limitations. One key barrier to addressing these disparities has been limited engagement of African Americans in the development and evaluation of behavioral interventions for management of OA. Pain Coping Skills Training (CST) is a cognitive-behavioral intervention with shown efficacy to improve OA-related pain and other outcomes. Emerging data indicate pain CST may be a promising intervention for reducing racial disparities in OA symptom severity. However, there are important gaps in this research, including incorporation of stakeholder perspectives (e.g. cultural appropriateness, strategies for implementation into clinical practice) and testing pain CST specifically among African Americans with OA. This study will evaluate the effectiveness of a culturally enhanced pain CST program among African Americans with OA.

METHODS/DESIGN

This is a randomized controlled trial among 248 participants with symptomatic hip or knee OA, with equal allocation to a pain CST group and a wait list (WL) control group. The pain CST program incorporated feedback from patients and other stakeholders and involves 11 weekly telephone-based sessions. Outcomes are assessed at baseline, 12 weeks (primary time point), and 36 weeks (to assess maintenance of treatment effects). The primary outcome is the Western Ontario and McMaster Universities Osteoarthritis Index, and secondary outcomes include self-efficacy, pain coping, pain interference, quality of life, depressive symptoms, and global assessment of change. Linear mixed models will be used to compare the pain CST group to the WL control group and explore whether participant characteristics are associated with differential improvement in the pain CST program. This research is in compliance with the Helsinki Declaration and was approved by the Institutional Review Boards of the University of North Carolina at Chapel Hill, Durham Veterans Affairs Medical Center, East Carolina University, and Duke University Health System.

DISCUSSION

This culturally enhanced pain CST program could have a substantial impact on outcomes for African Americans with OA and may be a key strategy in the reduction of racial health disparities.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT02560922 , registered 9/22/2015.

Differences in Pain Coping Between Black and White Americans: A Meta-Analysis

Compared with white individuals, black individuals experience greater pain across clinical and experimental modalities. These race differences may be due to differences in pain-related coping. Several studies examined the relationship between race and pain coping; however, no meta-analytic review has summarized this relationship or attempted to account for differences across studies. The goal of this meta-analytic review was to quantify race differences in the overall use of pain coping strategies as well as specific coping strategies. Relevant studies were identified using electronic databases, an ancestry search, and by contacting authors for unpublished data. Of 150 studies identified, 19 met inclusion criteria, resulting in 6,489 participants and 123 effect sizes. All of the included studies were conducted in the United States. Mean effect sizes were calculated using a random effects model. Compared with white individuals, black individuals used pain coping strategies more frequently overall (standardized mean difference [d] = .25, P < .01), with the largest differences observed for praying (d = .70) and catastrophizing (d = .40). White individuals engaged in task persistence more than black individuals (d = -.28). These results suggest that black individuals use coping strategies more frequently, specifically strategies associated with poorer pain outcomes. Future research should examine the extent to which the use of these strategies mediates race differences in the pain experience.

PERSPECTIVE

Results of this meta-analysis examining race differences in pain-related coping indicate that, compared with white individuals, black individuals use coping strategies more frequently, specifically those involving praying and catastrophizing. These differences in coping may help to explain race differences in the pain experience.

Within-Day Variability of Fatigue and Pain Among African Americans and Non-Hispanic Whites With Osteoarthritis of the Knee

OBJECTIVE

Fatigue is common among persons with osteoarthritis (OA), but little is known about racial/ethnic differences in the prevalence, correlates, or dynamics of fatigue in OA. This research therefore used experience sampling methodology (ESM) to examine fatigue and pain at global and momentary levels among African Americans and non-Hispanic whites with OA.

METHODS

Thirty-nine African Americans and 81 non-Hispanic whites with physician-diagnosed knee OA completed a baseline interview and an ESM protocol assessing fatigue, pain, and mood 4 times daily for 7 days. In addition to analyzing basic group differences, multilevel modeling examined within- versus between-subject patterns and correlates of variability in momentary fatigue, controlling for demographics and other potential confounders.

RESULTS

Both racial groups experienced moderate levels of fatigue; however, there were clear individual differences in both mean fatigue level and variability across momentary assessments. Mean fatigue levels were associated with global pain and depression. Increase in fatigue over the course of the day was much stronger among non-Hispanic whites than African Americans. Momentary fatigue and pain were closely correlated. Mean fatigue predicted variability in mood; at the momentary level, both fatigue and pain were independently associated with mood.

CONCLUSION

Fatigue is a significant factor for both African Americans and non-Hispanic whites with OA, and is negatively related to quality of life. Pain symptoms, at both the momentary level and across individuals, were robust predictors of fatigue. Although overall levels of reported symptoms were similar across these 2 groups, the pattern of fatigue symptoms across the day differed.

Vitamin D status and pain sensitization in knee osteoarthritis: a critical review of the literature

Diagnostic imaging of disease severity has been found thus far to be a relatively modest predictor of knee osteoarthritis (OA) pain and disability, suggesting that other factors likely contribute to clinical symptoms in this condition. Recent evidence suggests that sensitization of the peripheral and central pathways that process nociceptive information (i.e., pain sensitization) is an important contributor to knee OA clinical symptoms. Furthermore, low levels of vitamin D have been found to be associated with the presence of pain sensitization, as well as the overall experience of clinical pain severity in knee OA. African-Americans with knee OA may be at increased risk for poor clinical outcomes given evidence of lower vitamin D levels as well as greater pain sensitization compared with non-Hispanic whites. Whether vitamin D supplementation is effective for alleviating knee OA clinical symptoms is an important topic to be addressed in future research with racially diverse samples that include sufficient numbers of African-Americans.

Associations of coping strategies with diary based pain variables among Caucasian and African American patients with osteoarthritis

PURPOSE

The purposes of this study are to examine the associations between pain coping strategies and daily diary-based pain measures and to determine whether these associations differed by race (African American and Caucasian).

METHODS

Primary care patients from the Durham Veterans Affairs and Duke University Medical Centers (N = 153) with hand, hip, or knee osteoarthritis (OA) completed electronic pain diaries on a one-weekend day and one weekday. The maximum, range (maximum minus minimum pain), and area under the curve (AUC) of joint pain ratings were calculated. Pain coping (Coping Strategies Questionnaire (CSQ) coping attempts, catastrophizing, and praying/hoping subscale scores) was assessed prior to diary entries and at the end of each diary day (total, problem-focused, and emotion-focused scores from Stone and Neale's Daily Coping Inventory). Pearson correlations between pain variables and coping measures were examined. Linear mixed models were fit including age, race, weekend/weekday, study enrollment site, education level, pain medication use, self-rated health, Arthritis Impact Measurement Scales affect and function subscales, and interactions of coping measures with race and weekend day/weekday status.

RESULTS

Correlations between coping and pain measures were 0.12-0.45. In adjusted models, maximum pain and pain range were associated with all three diary-based coping measures; maximum pain was associated with CSQ coping attempts; and AUC was associated with CSQ praying/hoping. Interactions were not significant.

CONCLUSIONS

Among participants with OA, pain coping strategies were related to important aspects of the pain experience, particularly pain range and maximum pain. However, race did not modify associations of pain coping strategy use and the pain experience.

Modifiable lifestyle factors are associated with lower pain levels in adults with knee osteoarthritis

Pain is the most important osteoarthritis (OA) symptom; however, it is poorly understood and markers of disease severity cannot explain pain variability. With no cure for OA, the authors recognized the need to identify modifiable factors to decrease pain and increase physical function. This study examined factors that characterize OA patients experiencing different levels of pain and investigated the relationships among these factors and OA pain.

BACKGROUND:

With no cure or effective treatments for osteoarthritis (OA), the need to identify modifiable factors to decrease pain and increase physical function is well recognized.

OBJECTIVE:

To examine factors that characterize OA patients at different levels of pain, and to investigate the relationships among these factors and pain.

METHODS:

Details of OA characteristics and lifestyle factors were collected from interviews with healthy adults with knee OA (n=197). The Western Ontario and McMaster Universities Osteoarthritis Index was used to assess pain. Factors were summarized across three pain score categories, and χ² and Kruskal-Wallis tests were used to examine differences. Multiple linear regression analysis using a stepwise selection procedure was used to examine associations between lifestyle factors and pain.

RESULTS:

Multiple linear regression analysis indicated that pain was significantly higher with the use of OA medications and higher body mass index category, and significantly lower with the use of supplements and meeting physical activity guidelines (≥150 min/week). Stiffness and physical function scores, bilateral knee OA, body mass index category and OA medication use were significantly higher with increasing pain, whereas self-reported health, servings of fruit, supplement use and meeting physical activity guidelines significantly lower. No significant differences across pain categories were found for sex, age, number of diseases, duration of OA, ever smoked, alcoholic drinks/week, over-the-counter pain medication use, OA supplement use, physical therapy use, servings of vegetables or minutes walked/week.

CONCLUSIONS:

Healthy weight maintenance, exercise for at least 150 min/week and appropriate use of medications and supplements represent important modifiable factors related to lower knee OA pain.

Racial disparities in total ankle arthroplasty utilization and outcomes

INTRODUCTION

The objective of this study was to examine the racial disparities in total ankle arthroplasty (TAA) utilization and outcomes.

METHODS

We used the National Inpatient Sample (NIS) to study the time-trends. Race was categorized as White and Black. Utilization rates were calculated for the U.S. general population per 100,000. Hospital length of stay, discharge disposition and mortality after TAA were assessed. We used the Cochran Armitage trend test to assess time-trends from 1998 to 2011 and chi-square test to compare TAA utilization. We used analysis of variance or chi-squared test to compare the characteristics of Whites and Blacks undergoing TAA and logistic regression to compare mortality, length of stay and discharge to home versus medical facility.

RESULTS

The mean ages for Whites undergoing TAA were 62 years and for Blacks was 52 years. Significant racial disparities were noted in TAA utilization rates (/100,000) in 1998, 0.14 in Whites vs. 0.07 in Blacks (P<0.0001; 2-fold) and in 2011, 1.17 in Whites vs. 0.33 in Blacks (P<0.0001; 4-fold). Racial disparities in TAA utilization increased significantly from 1998 to 2011 (P<0.0001). There was a trend towards statistical significance for the difference in the length of hospital stay in Blacks vs. Whites (52.9% vs. 44.3% with length of hospital stay higher than the median; P=0.08). Differences in the proportion discharged to an inpatient medical facility after TAA, 16.6% Blacks vs. 13.4% Whites, were not significant (P=0.36).

CONCLUSIONS

This study demonstrated significant racial disparities with lower TAA utilization and suboptimal outcomes in Blacks compared to Whites. Further studies are needed to understand the mediators of these disparities and to assess whether these mediators can be targeted to reduce racial disparities in TAA.

Factors associated with pain experience outcome in knee osteoarthritis

OBJECTIVE

Few strategies to improve pain outcome in knee osteoarthritis (OA) exist in part because how best to evaluate pain over the long term is unclear. Our objectives were to determine the frequency of a good pain experience outcome based on previously formulated OA pain stages and test the hypothesis that less depression and pain catastrophizing and greater self-efficacy and social support are each associated with greater likelihood of a good outcome.

METHODS

Study participants, all with knee OA, reported pain stage at baseline and 2 years. Baseline assessments utilized the Geriatric Depression Scale, Pain Catastrophizing Scale, Arthritis Self-Efficacy Scale, and Medical Outcomes Study social support survey. Using pain experience stages, good outcome was defined as persistence in or movement to no pain or stage 1 (predictable pain, known trigger) at 2 years. A multivariable logistic regression model was developed to identify independent predictors of a good outcome.

RESULTS

Of 212 participants, 136 (64%) had a good pain outcome and 76 (36%) a poor pain outcome. In multivariable analysis, higher self-efficacy was associated with a significantly higher likelihood of good outcome (adjusted odds ratio [OR] 1.14 [95% confidence interval (95% CI) 1.04-1.24]); higher pain catastrophizing was associated with a significantly lower likelihood of good outcome (adjusted OR 0.88 [95% CI 0.83-0.94]).

CONCLUSION

This stage-based measure provides a meaningful and interpretable means to assess pain outcome in knee OA. The odds of a good 2-year outcome in knee OA were lower in persons with greater pain catastrophizing and higher in persons with greater self-efficacy. Targeting these factors may help to improve pain outcome in knee OA.

Self-efficacy and arthritis disability: An updated synthesis of the evidence base and its relevance to optimal patient care

Self-efficacy, denoting the degree of confidence an individual has in carrying out a specific activity, was initially discussed in the 1970s as a potential correlate of disease outcomes. Drawn from 35 years of related research, this review provides an updated understanding of the concept of self-efficacy and its relevance for arthritis management. There is a consistent link between self-efficacy, arthritis pain and disability, and adherence to recommended therapeutic strategies. A wide variety of intervention strategies improve arthritis self-efficacy, as well as outcomes. Steps to assess and intervene thoughtfully to maximize self-efficacy beliefs are likely to impact arthritis disability outcomes quite favorably and significantly, regardless of disease type, duration, or sociodemographic factors.

Tibiofemoral subchondral surface ratio (SSR) is a predictor of osteoarthritis symptoms and radiographic progression: data from the Osteoarthritis Initiative (OAI)

OBJECTIVE

Symptomatic knee osteoarthritis (OA) is poorly correlated with radiographic severity, but subchondral bone measures may be useful for risk assessment as bone shape is grossly unaffected at early radiographic stages. We sought to determine whether compartment-specific size mismatch in the naturally asymmetric tibiofemoral joint, measured as tibiofemoral subchondral surface ratio (SSR): (1) predicts incident symptoms, (2) predicts incident or progressive OA, (3) is reproducible and time invariant.

DESIGN

OA Initiative participants with baseline MRIs and up to 48-month follow-up (n = 1,338) were analyzed. Logistic regression was used to determine the association between SSR and incident symptoms, incident OA, and progression of OA after adjusting for demographic, radiologic, injury-related, and lifestyle-related factors. Reproducibility was assessed as % coefficient of variation (CV) on repeat MRI studies at baseline and 24 months.

RESULTS

Increased medial SSR is protective against incident symptoms at 48 months (per 0.1 increase: OR 0.48 CI 0.30, 0.75; P = 0.001). Increased lateral SSR values are protective against lateral OA incidence (OR 0.23 CI 0.06, 0.77; P = 0.016) or progression (OR 0.66 CI 0.43, 0.99; P = 0.049) at 24 months. Both medial and lateral SSR are stable over time (medial: mean change 0.001 SD 0.016; lateral: mean change 0.000 SD 0.017) and are highly reproducible (3.0% CV medial SSR; 2.7% CV lateral SSR).

CONCLUSIONS

A larger medial SSR is protective against developing OA-related symptoms. A larger lateral SSR is protective against lateral OA incidence or progression. Finally, lateral and medial SSR are stable over time and are highly reproducible across MRI studies.

The avoidance model in knee and hip osteoarthritis: a systematic review of the evidence

The avoidance model in patients with knee and hip osteoarthritis (OA) hypothesizes that pain and psychological distress lead to avoidance of activities, and thereby to muscle weakness and activity limitations. This paper systematically reviews the scientific evidence for the validity of this avoidance model. A qualitative data synthesis was used to identify levels of evidence. Sixty studies were included. In knee OA, strong evidence was found that avoidance of activities is associated with activity limitations via muscle weakness (mediation by muscle weakness), strong evidence was found for an association between muscle weakness and activity limitations, and weak evidence was found that pain and psychological distress are associated with muscle weakness via avoidance of activities (mediation by avoidance). In hip OA, weak evidence was found for mediation by muscle weakness; and strong evidence was found for an association between muscle weakness and activity limitations. More research is needed on the consecutive associations between pain or psychological distress, avoidance of activities and muscle weakness, and to confirm causal relationships.

Temporal summation of pain as a prospective predictor of clinical pain severity in adults aged 45 years and older with knee osteoarthritis: ethnic differences

OBJECTIVE

Enhanced pain facilitation is reportedly an important contributor to the clinical pain experiences of individuals with knee osteoarthritis (OA). Ethnic differences in the prevalence and severity of knee OA in addition to associated pain are also well documented. Temporal summation (TS) of pain is a widely applicable quantitative sensory testing method that invokes neural mechanisms related to pain facilitatory processes. This study tested whether TS of pain, an index of pain facilitation, differentially predicts the clinical pain experiences of African Americans and non-Hispanic whites with symptomatic knee OA.

METHODS

A total of 225 study participants underwent assessment of TS of mechanical and heat pain stimuli applied to their most symptomatic knee and their ipsilateral hand (mechanical) or forearm (heat). Using telephone-based surveys, participants subsequently reported their average and worst clinical pain severity across four consecutive weeks after the assessment of TS.

RESULTS

In predicting future clinical pain, ethnicity interacted with TS of mechanical pain (but not heat pain), such that TS of mechanical pain at the knee significantly predicted greater clinical ratings of average (b = 0.02, p = .016) and worst (b = 0.02, p = .044) clinical pain for non-Hispanic whites but not African Americans (p values > .30).

CONCLUSIONS

These results reveal the importance of considering ethnicity when examining pain facilitation and the clinical pain of individuals with symptomatic knee OA. The results of this study are discussed in terms of ethnic differences in the predictors of clinical pain experiences among African Americans and non-Hispanic whites with knee OA.

Perceived racial discrimination, but not mistrust of medical researchers, predicts the heat pain tolerance of African Americans with symptomatic knee osteoarthritis

OBJECTIVE

Studies have shown that perceived racial discrimination is a significant predictor of clinical pain severity among African Americans. It remains unknown whether perceived racial discrimination also alters the nociceptive processing of painful stimuli, which, in turn, could influence clinical pain severity. This study examined associations between perceived racial discrimination and responses to noxious thermal stimuli among African Americans and non-Hispanic Whites. Mistrust of medical researchers was also assessed given its potential to affect responses to the noxious stimuli.

METHOD

One-hundred and 30 (52% African American, 48% non-Hispanic White) community-dwelling older adults with symptomatic knee osteoarthritis completed two study sessions. In session one, individuals provided demographic, socioeconomic, physical and mental health information. They completed questionnaires related to perceived lifetime frequency of racial discrimination and mistrust of medical researchers. In session two, individuals underwent a series of controlled thermal stimulation procedures to assess heat pain sensitivity, particularly heat pain tolerance.

RESULTS

African Americans were more sensitive to heat pain and reported greater perceived racial discrimination as well as greater mistrust of medical researchers compared with non-Hispanic Whites. Greater perceived racial discrimination significantly predicted lower heat pain tolerance for African Americans but not non-Hispanic Whites. Mistrust of medical researchers did not significantly predict heat pain tolerance for either racial group.

CONCLUSION

These results lend support to the idea that perceived racial discrimination may influence the clinical pain severity of African Americans via the nociceptive processing of painful stimuli.

Preoperative patient characteristics and outcomes of total knee arthroplasty in a multiethnic Asian population stratified by ethnicity

We aim to compare the patient profile and outcomes after TKA between the different racial groups in Singapore. Prospective data were collected from 364 patients who underwent TKA in Singapore General Hospital from January 2006 to May 2010. Patients were stratified according to ethnicity and we compared their preoperative demographic data, Short-Form 36 (SF-36), Oxford Knee (OKS) as well as Knee Society Scores (KSS). Malays were younger (62.0 ± 5.3) at time of surgery (p=0.05) and the body mass index of Chinese (27.9 ± 4.7) was lower than Malay (30.4 ± 5.0) and Indian (31.5 ± 4.5) patients (P<0.005). Malay (40.3 ± 11.0) and Indian (39.2 ± 9.3) patients had less favourable preoperative OKS than Chinese (35.9 ± 7.8) patients (P<0.05). All 3 ethnic groups achieved statistically significant improvements in outcome measures but did not differ significantly between the ethnicities.

Missed opportunities for depression screening in patients with arthritis in the United States

BACKGROUND

Arthritis affects 20 % of the adult US population and is associated with comorbid depression. Depression screening guidelines have been endorsed for high-risk groups, including persons with arthritis, in the hopes that screening will increase recognition and use of appropriate interventions.

OBJECTIVE

To examine national rates of depression and depression screening for patients with arthritis between 2006 and 2010.

PARTICIPANTS AND DESIGN

We used nationally representative cross-sections of ambulatory visits in the United States from the National Ambulatory Medical Care Survey from 2006 to 2010, which included 18,507 visits with a diagnosis of arthritis. When weighted to the US population, this total represents approximately 644 million visits.

MEASUREMENTS

Visits where arthritis was listed among diagnoses. Outcomes were survey-weighted estimates of depression and prevalence of depression screening among patients with arthritis across patient and physician characteristics.

KEY RESULTS

Of the 644,419,374 visits with arthritis listed, 83,574,127 (13 %) were associated with a comorbid diagnosis of depression. The odds ratio for comorbid depression with arthritis was 1.42 (95 % CI 1.3, 1.5). Depression screening occurred at 3,835,000 (1 %) visits associated with arthritis. When examining the rates of depression screening between ambulatory visits with and without arthritis listed, there was no difference in depression screening rates; both were approximately 1 %. There was no difference in screening rates by provider type. Compared to visits with other common, chronic conditions, the prevalence of depression at arthritis visits was high (13 per 100 visits), although the prevalence of depression screening at arthritis visits was low (0.68 per 100 visits).

CONCLUSIONS

Despite the high prevalence of depression with arthritis, screening for depression was performed at few arthritis visits, representing missed opportunities to detect a common, serious comorbidity. Improved depression screening by providers would identify affected patients, and may lead to appropriate interventions such as mental health referrals and/or treatment with anti-depressants.