Hospital Rheumatoid Arthritis Research Articles

Prevalence and Characteristics of Adults with Difficult-to-Treat Rheumatoid Arthritis in a Large Patient Registry.

An estimated 5-20% of patients with rheumatoid arthritis (RA) fail multiple treatments and are considered "difficult-to-treat" (D2T), posing a substantial clinical challenge for rheumatologists. A European Alliance of Associations for Rheumatology (EULAR) task force proposed a definition of D2T-RA in 2021. We applied EULAR's D2T definition in a cohort of patients with established RA to assess prevalence and we compared clinical characteristics of participants with D2T-RA with matched comparisons. Data from the longitudinal Brigham and Women's Hospital Rheumatoid Arthritis Sequential Study (BRASS) registry was used. Participants were classified as D2T if they met EULAR's definition. A comparison group of non-D2T RA patients were matched 2:1 to every D2T patient, and differences in characteristics were evaluated in descriptive analyses. Prevalence rates of D2T were estimated using Poisson regression. We estimated the prevalence of D2T-RA to be 14.4 (95% CI: 12.8-16.3 per 100 persons) among 1,581 participants with RA, and 22.3 (95% CI: 19.9-25.0 per 100 persons) among 1,021 who were biologic/targeted synthetic DMARD experienced. We observed several differences in demographics, comorbidities, and RA disease activity between D2T-RA and non-D2T RA comparisons. Varying EULAR sub-criteria among all participants in BRASS resulted in a range of D2T-RA prevalence rates, from 0.6-17.5 per 100 persons. EULAR's proposed definition of D2T-RA identifies patients with RA who have not achieved treatment targets. Future research should explore heterogeneity in these patients and evaluate outcomes to inform the design of future studies aimed at developing more effective RA management protocols.

Supplementing Claims Data with Electronic Medical Records to Improve Estimation and Classification of Rheumatoid Arthritis Disease Activity: A Machine Learning Approach.

ObjectivePrevious attempts to estimate rheumatoid arthritis (RA) disease activity using claims data only did not yield high performance. We aimed to assess whether supplementing claims data with readily available electronic medical record (EMR) data might result in improvement.MethodsWe used a subset of the Brigham and Women's Hospital Rheumatoid Arthritis Sequential Study (BRASS) that had linked Medicare claims. The disease activity score in 28 joints with C‐reactive protein (DAS28‐CRP) was considered the gold standard of measure. Variables in the linked Medicare claims, as well as EMR recorded in the preceding one‐year period were used as potential explanatory variables. We constructed three models: “Claims‐Only,” “Claims + Medications,” and “Claims + Medications + Labs (laboratory data from EMR). We selected variables via adaptive LASSO. Model performance was measured with adjusted R2 for continuous DAS28‐CRP and C‐statistics for binary category classification (high/moderate vs low disease activity/remission).ResultsWe identified 300 patients with laboratory data and linked Medicare claims. The mean age was 68 years and 80% were female. The mean (SD) DAS28‐CRP was 3.6 (1.6) and 51% had high or moderate DAS28‐CRP. For the continuous estimation, the adjusted R2 was 0.02 for Claims‐Only, 0.09 for Claims + Medications, and 0.18 for Claims + Medications + Labs. The C‐statistics for discriminating the binary categories were 0.61 for Claims‐Only, 0.68 for Claims + Medications, and 0.76 for Claims + Medications + Labs.ConclusionAdding EMR‐derived variables to claims‐derived variables resulted in modest improvement. Even with EMR variables, we were unable to estimate continuous DAS28‐CRP satisfactorily. However, in claims‐EMR models, we were able to discriminate between binary categories of disease activity with reasonable accuracy.

Association of Changes in Anticitrullinated Protein Antibody Levels With Resource Use and Disease Activity Measures in Rheumatoid Arthritis Patients a US Observational Cohort

PurposeAnticitrullinated protein antibody (ACPA) concentration, beyond ACPA positivity, is indicative of more aggressive radiographic progression in patients with rheumatoid arthritis (RA). However, there is limited information on the association of changes in ACPA with resource use measures and/or disease activity measures. We evaluate associations between changes in levels of ACPA and outcomes, including durable medical equipment (DME) use, hospitalizations, and disease activity, in patients with established RA. MethodsPatients from the Brigham and Women's Hospital Rheumatoid Arthritis Sequential Study who had ACPA measurements at baseline and month 12 were included. Changes in ACPA levels from baseline to month 12 were categorized as a decrease (<−10%), no change (−10% to +10%), or increase (>+10%). DME use and hospitalizations were assessed twice yearly using patient questionnaires; disease activity was assessed annually. Binary multivariate logistic regression was used to analyze the association between changes in ACPA levels and DME use and hospitalizations; linear regression was used to assess the association with disease activity. FindingsOf 840 patients included in the analysis, 291 (34.6%), 266 (31.7%), and 283 (33.7%) had a decrease, no change, or increase in ACPA levels, respectively. A decrease in ACPA levels was associated with a reduction in DME use (adjusted odds ratio [aOR] = 0.64; 95% CI, 0.44–0.93; P = 0.02) and hospitalizations (aOR = 0.62; 95% CI, 0.41–0.95; P = 0.03) versus no change or increase. Adjusted mean changes in disease activity score in 28 joints (C-reactive protein), total and swollen joint counts, and pain scores were significantly greater in patients with decreased ACPA levels versus those with no change or increase (P < 0.05). ImplicationsAmong patients with RA, reductions in ACPA levels of >10% were associated with reductions in DME use, hospitalizations, and disease activity. ClinicalTrials.gov identifier: NCT01793103.

Association of anti-cyclic citrullinated protein antibodies, erosions, and rheumatoid factor with disease activity and work productivity: A patient registry study.

To evaluate associations between the presence of anti-cyclic citrullinated protein antibodies (anti-CCP) and rheumatoid factor (RF) and other outcomes, including joint erosions and both clinical and economic endpoints, in patients with rheumatoid arthritis (RA). Data from the Brigham and Women's Hospital Rheumatoid Arthritis Sequential Study (BRASS), a prospective registry of adult RA patients with established or recent-onset RA, were analyzed. Logistic regression models were constructed to test associations between anti-CCP/RF seropositivity and erosive disease and the presence of anti-CCP/RF seropositivity plus erosive disease and (1) RA severity; (2) hospitalizations; (3) durable medical equipment (DME) use; and (4) worker productivity (e.g., employment status). Covariates in these models included patient age, gender, race, body mass index (BMI), number of comorbidities, and treatment. Among 1309 registrants, those who were positive (vs. negative) for anti-CCP were 2.72 times more likely to have erosions (OR = 2.72; 95% CI: 1.77-4.18; P < 0.001). Individuals positive (vs. negative) for RF were 36% more likely to have erosions (95% CI: 0.88-2.08; P = 0.162). Patients with anti-CCP seropositivity and erosions were significantly more likely to: (1) have higher disease activity as measured by the Disease Activity Score in 28 joints C-reactive protein (DAS28-CRP ≥ 2.6); (2) be hospitalized; (3) use DME; and (4) be unemployed, disabled, or long-term disabled. For the first time in a "real-world" setting including patients with both recent-onset and chronic RA, this study demonstrated that the combination of anti-CCP seropositivity and erosions were significantly associated with more adverse clinical and health-economic consequences, including a lower probability of low disease activity and higher health resource utilization, despite use of biologic disease-modifying antirheumatic drugs by many patients. This dual presentation may signal a need for more intensive therapies, even when observed in patients with chronic, as well as recent-onset, RA. Trial registration [Brigham and Women's Hospital (BWH) Rheumatoid Arthritis Sequential Study; Registry URL: https://clinicaltrials.gov/ct2/show/NCT01793103; ClinicalTrials.gov Identifier NCT01793103].

Identification of smoking using Medicare data--a validation study of claims-based algorithms.

This study examined the accuracy of claims-based algorithms to identify smoking against self-reported smoking data. Medicare patients enrolled in the Brigham and Women's Hospital Rheumatoid Arthritis Sequential Study were identified. For each patient, self-reported smoking status was extracted from Women's Hospital Rheumatoid Arthritis Sequential Study and the date of this measurement was defined as the index-date. Two algorithms identified smoking in Medicare claims: (i) only using diagnoses and procedure codes and (ii) using anti-smoking prescriptions in addition to diagnoses and procedure codes. Both algorithms were implemented: first, only using 365-days pre-index claims and then using all available pre-index claims. Considering self-reported smoking status as the gold standard, we calculated specificity, sensitivity, positive predictive value, negative predictive value (NPV), and area under the curve (AUC). A total of 128 patients were included in this study, of which 48% reported smoking. The algorithm only using diagnosis and procedure codes had the lowest sensitivity (9.8%, 95%CI 2.4%-17.3%), NPV (54.9%, 95%CI 46.1%-63.9%), and AUC (0.55, 95%CI 0.51-0.59) when applied in the period of 365 days pre-index. Incorporating pharmacy claims and using all available pre-index information improved the sensitivity (27.9%, 95%CI 16.6%-39.1%), NPV (60.4%, 95%CI 51.3%-69.5%), and AUC (0.64, 95%CI 0.58-0.70). The specificity and positive predictive value was 100% for all the algorithms tested. Claims-based algorithms can identify smokers with limited sensitivity but very high specificity. In the absence of other reliable means, use of a claims-based algorithm to identify smoking could be cautiously considered in observational studies.

An external validation study reporting poor correlation between the claims-based index for rheumatoid arthritis severity and the disease activity score.

IntroductionWe conducted an external validation study to examine the correlation of a previously published claims-based index for rheumatoid arthritis severity (CIRAS) with disease activity score in 28 joints calculated by using C-reactive protein (DAS28-CRP) and the multi-dimensional health assessment questionnaire (MD-HAQ) physical function score.MethodsPatients enrolled in the Brigham and Women’s Hospital Rheumatoid Arthritis Sequential Study (BRASS) and Medicare were identified and their data from these two sources were linked. For each patient, DAS28-CRP measurement and MD-HAQ physical function scores were extracted from BRASS, and CIRAS was calculated from Medicare claims for the period of 365 days prior to the DAS28-CRP measurement. Pearson correlation coefficient between CIRAS and DAS28-CRP as well as MD-HAQ physical function scores were calculated. Furthermore, we considered several additional pharmacy and medical claims-derived variables as predictors for DAS28-CRP in a multivariable linear regression model in order to assess improvement in the performance of the original CIRAS algorithm.ResultsIn total, 315 patients with enrollment in both BRASS and Medicare were included in this study. The majority (81%) of the cohort was female, and the mean age was 70 years. The correlation between CIRAS and DAS28-CRP was low (Pearson correlation coefficient = 0.07, P = 0.24). The correlation between the calculated CIRAS and MD-HAQ physical function scores was also found to be low (Pearson correlation coefficient = 0.08, P = 0.17). The linear regression model containing additional claims-derived variables yielded model R2 of 0.23, suggesting limited ability of this model to explain variation in DAS28-CRP.ConclusionsIn a cohort of Medicare-enrolled patients with established RA, CIRAS showed low correlation with DAS28-CRP as well as MD-HAQ physical function scores. Claims-based algorithms for disease activity should be rigorously tested in distinct populations in order to establish their generalizability before widespread adoption.

Detection of Rheumatoid Arthritis-Interstitial Lung Disease Is Enhanced by Serum Biomarkers.

Interstitial lung disease (ILD), a leading cause of morbidity and mortality in rheumatoid arthritis (RA), is highly prevalent, yet RA-ILD is underrecognized. To identify clinical risk factors, autoantibodies, and biomarkers associated with the presence of RA-ILD. Subjects enrolled in Brigham and Women's Hospital Rheumatoid Arthritis Sequential Study (BRASS) and American College of Rheumatology (ACR) cohorts were evaluated for ILD. Regression models were used to assess the association between variables of interest and RA-ILD. Receiver operating characteristic curves were generated in BRASS to determine if a combination of clinical risk factors and autoantibodies can identify RA-ILD and if the addition of investigational biomarkers is informative. This combinatorial signature was subsequently tested in ACR. A total of 113 BRASS subjects with clinically indicated chest computed tomography scans (41% with a spectrum of clinically evident and subclinical RA-ILD) and 76 ACR subjects with research or clinical scans (51% with a spectrum of RA-ILD) were selected. A combination of age, sex, smoking, rheumatoid factor, and anticyclic citrullinated peptide antibodies was strongly associated with RA-ILD (areas under the curve, 0.88 for BRASS and 0.89 for ACR). Importantly, a combinatorial signature including matrix metalloproteinase 7, pulmonary and activation-regulated chemokine, and surfactant protein D significantly increased the areas under the curve to 0.97 (P = 0.002, BRASS) and 1.00 (P = 0.016, ACR). Similar trends were seen for both clinically evident and subclinical RA-ILD. Clinical risk factors and autoantibodies are strongly associated with the presence of clinically evident and subclinical RA-ILD on computed tomography scan in two independent RA cohorts. A biomarker signature composed of matrix metalloproteinase 7, pulmonary and activation-regulated chemokine, and surfactant protein D significantly strengthens this association. These findings may facilitate identification of RA-ILD at an earlier stage, potentially leading to decreased morbidity and mortality.

Subgrouping of patients with rheumatoid arthritis based on pain, fatigue, inflammation, and psychosocial factors.

Among patients with rheumatoid arthritis (RA), pain may be attributed to peripheral inflammation or other causes, such as central pain mechanisms. The aim of this study was to use self-report measures and physical examination findings to identify clusters of RA patients who may have different causes of pain as well as different prognoses and treatment options. Data from 169 RA patients with pain scores of >0 (on a 10-point numeric rating scale) in the Brigham and Women's Hospital Rheumatoid Arthritis Sequential Study were analyzed. The patients completed questionnaires on pain, fatigue, and psychosocial factors. A hierarchical agglomerative clustering procedure with Ward's method was used to obtain subgroups. Multivariate analysis of variance was used to determine the contribution of each variable in a cluster. General linear regression models were used to examine differences in clinical characteristics across subgroups. Discriminant analyses were performed to determine coefficients for linear combinations of variables that assigned cluster membership to individual cases. Three clusters best fit these data. Cluster 1 consisted of 89 individuals with low levels of inflammation, pain, fatigue, and psychosocial distress. Cluster 2 consisted of 57 individuals with minimal inflammation but high levels of pain, fatigue, and psychosocial distress. Cluster 3 consisted of 23 individuals with active inflammatory disease, manifested by high swollen joint counts, high C-reactive protein levels, and high levels of pain and fatigue. Although most patients had low levels of inflammation, pain, and fatigue, 47.3% continued to report having moderate to high levels of pain and fatigue. Most of these patients had minimal signs of inflammation but high levels of fatigue, pain catastrophizing, and sleep disturbance, indicative of a chronic widespread pain syndrome.

Functional Impact of a Spectrum of Interstitial Lung Abnormalities in Rheumatoid Arthritis

Approximately 10% of patients with rheumatoid arthritis (RA) have interstitial lung disease (ILD), and one-third have subclinical ILD on chest CT scan. In this study, we aimed to further characterize functional decrements in a spectrum of RA-associated ILD. All subjects were enrolled in the Brigham and Women's Hospital Rheumatoid Arthritis Sequential Study (BRASS). The presence of interstitial lung abnormalities (ILAs) on clinically indicated chest CT scans was determined using a previously validated sequential reading method. Univariate and multivariate analyses were used to assess the association between degree of ILAs and physiologic, functional, and demographic variables of interest. Of 1,145 BRASS subjects, 91 subjects (8%) were included in this study. Twelve had radiologically severe ILAs, 34 had ILAs, and 38 had no ILAs on CT scan. Subjects with radiologically severe ILAs were older (P = .0037), had increased respiratory symptoms (cough, P = .027; dyspnea, P = .010), and more severe RA disease (rheumatoid factor, P = .018; total swollen joints, P = .046) compared with subjects with no ILAs. Participants also had a trend toward having an increased smoking history (P = .16) and having lower FVC % predicted (77% vs 94%, P = .097) and diffusion capacity of carbon monoxide % predicted (52% vs 77%, P = .068). Similar but attenuated increases in respiratory symptoms, functional decrements, and RA disease severity were observed in subjects with ILAs compared with those with no ILAs. We have shown that patients with RA have varying degrees of ILAs that are associated with a spectrum of functional and physiologic decrements. Our findings suggest that improved risk stratification and detection of ILAs will provide a therapeutic window that could improve RA-ILD outcomes.

SAT0039 Development and Validation of A Prognostic Clinical Model for RAPID Radiographic Progression in Patients with RA

BackgroundIdentification of factors predictive of rapid radiographic progression (RRP) in RA pts will enable clinicians and policymakers to target appropriate treatment strategies to at-risk pts.ObjectivesTo evaluate baseline (BL) factors associated...

FRI0182 Development of A Multimorbidity Index: Impact on Quality of Life Using A Rheumatoid Arthritis Cohort

BackgroundMultimorbidity is an important patient-centered concept that needs to be considered when deciding on diagnostic or therapeutic strategies for typical rheumatoid arthritis (RA) patients. In chronic diseases like RA, health...

THU0246 Differences (OR Variations) in Physical Functioning in RA by Disease Activity Levels Defined by Das, CDai, and SDAI in Clinical Practice

BackgroundMultiple composite measures of disease activity, such as Disease Activity Score (DAS), Clinical Disease Activity Index (CDAI) and Simplified Disease Activity Index (SDAI), are currently recommended and used to evaluate...

FRI0003 Quality of Life and Economic Benefits of Remission/Low Disease Activity in Patients with Rheumatoid Arthritis in Clinical Practice Setting

BackgroundRecent studies, primarily in clinical trial settings, have suggested that attaining remission/low disease activity (LDA) in patients with early-stage RA contributes to improved clinical outcomes.ObjectivesEvaluate the associations between achievement of...

Associations of Smoking and Alcohol Consumption with Disease Activity and Functional Status in Rheumatoid Arthritis

To investigate the associations of smoking and alcohol consumption with disease activity and functional status in rheumatoid arthritis (RA). We conducted a prospective study consisting of 662 patients with RA who were followed up to 7 years from the Brigham and Women's Hospital Rheumatoid Arthritis Sequential Study. Smoking and alcohol consumption were assessed through yearly questionnaires. The disease activity and functional status were measured annually by the Disease Activity Score examined in 28 commonly affected joints using C-reactive protein (DAS28-CRP3) and the Modified Health Assessment Questionnaire (MHAQ). Linear mixed models were developed to assess the longitudinal effects of smoking and alcohol consumption on DAS28-CRP3 and MHAQ after adjustment for potential confounders. The HLA-DRB1 shared epitope (HLA-SE) by smoking and alcohol interactions were also evaluated in the analysis. The median followup time of the cohort was 4 years. Current smoking was not associated with DAS28-CRP3 in our study, but was associated with a higher MHAQ than nonsmokers with seropositive RA (p = 0.05). Alcohol consumption showed an approximate J-shaped relationship with MHAQ, with the minima occurring at 5.1-10.0 g/day. Compared to no alcohol use, alcohol consumption of 5.1-10.0 g/day was associated with a significant decrease of MHAQ (p = 0.02). When stratified by HLA-SE, the effect of alcohol consumption appeared to be stronger in HLA-SE-positive RA than HLA-SE-negative RA. We found that current smoking was associated with a worse functional status, while moderate alcohol consumption was associated with a better functional status in RA. Replications of these findings in other prospective studies are needed.

SAT0040 Prevalence and Predictors for Sustained Remission in Rheumatoid Arthritis

BackgroundDisease progression of RA is unpredictable and recurrence occurs frequently even in patients in remission. Since patients with short term remission are more likely to experience radiographic structural progression compared...

Validation of a novel multibiomarker test to assess rheumatoid arthritis disease activity

Objective Quantitative assessment of disease activity in rheumatoid arthritis (RA) is important for patient management, and additional objective information may aid rheumatologists in clinical decision making. We validated a recently developed multibiomarker disease activity (MBDA) test relative to clinical disease activity in diverse RA cohorts.Methods Serum samples were obtained from the Index for Rheumatoid Arthritis Measurement, Brigham and Women's Hospital Rheumatoid Arthritis Sequential Study, and Leiden Early Arthritis Clinic cohorts. Levels of 12 biomarkers were measured and combined according to a prespecified algorithm to generate the composite MBDA score. The relationship of the MBDA score to clinical disease activity was characterized separately in seropositive and seronegative patients using Pearson's correlations and the area under the receiver operating characteristic curve (AUROC) to discriminate between patients with low and moderate/high disease activity. Associations between changes in MBDA score and clinical responses 6–12 weeks after initiation of anti–tumor necrosis factor or methotrexate treatment were evaluated by the AUROC.Results The MBDA score was significantly associated with the Disease Activity Score in 28 joints using the C-reactive protein level (DAS28-CRP) in both seropositive (AUROC 0.77, P < 0.001) and seronegative (AUROC 0.70, P < 0.001) patients. In subgroups based on age, sex, body mass index, and treatment, the MBDA score was associated with the DAS28-CRP (P < 0.05) in all seropositive and most seronegative subgroups. Changes in the MBDA score at 6–12 weeks could discriminate both American College of Rheumatology criteria for 50% improvement responses (P = 0.03) and DAS28-CRP improvement (P = 0.002). Changes in the MBDA score at 2 weeks were also associated with subsequent DAS28-CRP response (P = 0.02).Conclusion Our findings establish the criterion and discriminant validity of a novel multibiomarker test as an objective measure of RA disease activity to aid in the management of RA in patients with this condition.

Using genetic and clinical data to understand response to disease-modifying anti-rheumatic drug therapy: data from the Brigham and Women's Hospital Rheumatoid Arthritis Sequential Study

The objective of this review is to report on the progress of the Brigham and Women's Hospital Rheumatoid Arthritis Sequential Study (BRASS) Registry data collection and summarize previous research in understanding therapeutic response to DMARDs using clinical and genetic data. The BRASS Registry, established in 2003, is a large, single-centre, prospective and observational cohort of 1100 RA patients. Patients with either new-onset or established RA disease are recruited from the practices of rheumatologists. Annual visits collect information on demographics, 28-joint DAS-CRP3 (DAS-28-CRP3), medication use, comorbidities and functional status (Modified Health Assessment Questionnaire, Short Form Health Survey 12). Two published studies have utilized BRASS to examine genetic predictors of treatment response. In a cross-sectional study, examining the association between candidate single nucleotide polymorphisms (SNPs) and disease activity in a subset of 120 RA patients on MTX monotherapy, the minor allele of ATIC rs4673993 was associated with low disease activity (P=0.01, DAS-28-CRP3≤3.2). In an international collaboration, 55 BRASS patients receiving anti-TNF therapy were genotyped for 31 SNPs associated with the risk of RA. With our collaborators, we discovered an SNP at the protein tyrosine phosphatase, receptor type, C (PTPRC) gene locus that was associated with EULAR 'good response'. With accurate data collection and the capacity to run genome-wide association studies and SNP analyses, the BRASS Registry has the ability to determine the contribution of genetic variants to disease onset and to assess their usefulness as biomarkers for treatment response and drug toxicity.

Investigation of candidate polymorphisms and disease activity in rheumatoid arthritis patients on methotrexate

We examined the association between candidate single nucleotide polymorphisms (SNPs) and disease activity in RA patients on MTX. Our population was drawn from the Brigham and Women's Hospital Rheumatoid Arthritis Sequential Study (BRASS), a prospective, observational cohort of RA patients. A total of 556 participants were genotyped using the Affymetrix 100K platform. Two hundred and sixty-two participants were on MTX therapy, including 120 on MTX monotherapy. The primary outcome was the disease activity score in 28 joints (DAS28-CRP). High disease activity was defined as DAS28-CRP >3.2. Low disease activity was defined as DAS28-CRP < or =3.2. We studied three candidate alleles in the ATIC, ITPA and MTHFR genes for association with DAS28-CRP. Among participants on MTX monotherapy, those carrying the minor allele of ATIC SNP rs4673993 were more likely to have low disease activity (P = 0.01). None of the other SNPs was associated with disease activity. Among patients on any MTX (combination or monotherapy), the minor allele of ATIC rs4673993 was also associated with low disease activity (P = 0.04). In this cross-sectional analysis, ATIC SNP rs4673993 was associated with low disease activity in patients on MTX. Further studies are needed to clarify the relationship between ATIC polymorphisms, disease activity and treatment response.

The validity of a rheumatoid arthritis medical records-based index of severity compared with the DAS28

The objective of this work was to assess the convergent validity of a previously developed rheumatoid arthritis medical records-based index of severity (RARBIS) by comparing it with the 28-joint Disease Activity Score (DAS28). This study was conducted in subjects within the Brigham and Women's Hospital Rheumatoid Arthritis Sequential Study (BRASS). We selected 100 patients with rheumatoid arthritis (RA) from the BRASS with DAS28 scores equally distributed in four quartiles. The medical records were reviewed to calculate the RARBIS, which includes indicators from the following categories: prior surgical history, radiologic and laboratory findings, clinical and functional status, and extra-articular manifestations. The Spearman correlation between the RARBIS and the DAS28 was assessed in the total study population and in relevant subgroups. We re-weighted on subscales and recalculated the RARBIS score. This was performed based on findings of correlations between the DAS28 and subscales; and also the result from a multiple linear regression with the DAS28 (as a dependent variable) and five subscales (as independent variables). The mean RARBIS was 4.36 (range 0–11). Among the total study cohort, the RARBIS was moderately correlated with the DAS28 (r = 0.41, 95% confidence interval [CI] 0.23–0.56). In subgroup analyses, including age, gender, rheumatoid factor status, and disease duration, we found no statistically significant differences in the correlations. After re-weighting, the correlation between the RARBIS and the DAS28 was somewhat improved (r = 0.48, 95% CI 0.31–0.62). In conclusion, the RARBIS correlated moderately well with the DAS28 in this population. The RARBIS has both face and convergent validity for patients with RA and relevant subgroups and may have application for medical records studies in patients with RA.

Screening for extensor tendon rupture in rheumatoid arthritis

Surgery can prevent extensor tendon rupture in the rheumatoid wrist but it is difficult to identify patients at risk. Extensor digiti minimi (EDM) usually ruptures first, but rupture may pass unnoticed because extensor digitorum communis (EDC) extends all four fingers simultaneously. We assessed the value of screening for EDM rupture by examining for absent independent extension of the little finger in a hospital rheumatoid arthritis population. The EDM test was performed in 550 previously unoperated wrists. Disease activity, joint damage, wrist swelling, tenderness and crepitus were recorded. Unsuspected EDM loss was found in nine of the 550 wrists (1.6%); dorsal synovitis was absent or minimal in eight and ulnar tenderness was absent in six. EDM loss was not associated with activity, severity or duration of disease. The EDM test is simple and cheap. It may identify patients at risk and permit prophylactic surgery before hand function is lost.