Limited Diagnostic and Prognostic Value of Routine Radiographs in Newly Presenting Arthritis Suspected of Rheumatoid Arthritis: A Retrospective Study.

OBJECTIVE: Current recommendations suggest that patients with newly presenting arthritis suspected of rheumatoid arthritis (RA) should undergo routine radiographs of hands and feet (X-HF) as the presence of RA-associated erosions might be of diagnostic and prognostic value. Our objective was to investigate the prevalence, diagnostic, and prognostic value of RA-associated erosions seen on routine X-HF in a large, recent cohort of patients with newly presenting arthritis. METHODS: A retrospective cohort study was performed between 2016 and 2019 in patients with newly presenting arthritis suspected of RA. Patients were included if arthritis was present at diagnosis, rheumatoid factor and anticitrullinated protein antibodies were measured, RA was noted in the differential diagnosis, and routine X-HF were conducted. Outcomes were the prevalence of one or more RA-associated erosion(s), and whether diagnostic or prognostic classification were changed by erosivity. Seronegative patients, patients without acute phase reactants, and patients with longer symptom duration were analyzed as subgroups. RESULTS: RA-associated erosions were found in 32 of 724 patients (4.4%, 95% confidence interval [95% CI] 3.1-6.2). Erosions led to a change of diagnostic classification in two patients (0.3%, 95% CI 0.01-1.1) and changed prognostic classification in three patients (0.4%, 95% CI 0.1-1.3). Seronegative patients and patients without elevated acute phase reactants had significantly lower prevalence of erosions (χ2 9.4, P = 0.002, χ2 6.5, P = 0.01). Longer symptom duration was not associated with a different prevalence of erosions (χ2 0.4, P = 0.81). CONCLUSION: The recommendation of conducting routine X-HF in patients with newly presenting arthritis suspected of RA might be reconsidered due to low prevalence of early erosive disease and lack of diagnostic and prognostic value.

The added value of predictive biomarkers in treat-to-target strategies for rheumatoid arthritis patients: a conceptual modelling study.

OBJECTIVES: To quantify the additional value of a hypothetical biomarker predicting response to treatment for RA regarding efficacy and costs by using a modelling design. METHODS: A Markov model was built comparing a usual care T2T strategy with a biomarker-steered strategy for RA patients starting biologic therapy. Outcome measures include time spent in remission or low disease activity (LDA) and costs. Four additional scenario analyses were performed by varying biomarker or clinical care characteristics: (i) costs of the biomarker; (ii) sensitivity and specificity of the biomarker; (iii) proportion of eligible patients tapering; and (iv) medication costs. RESULTS: In the base model, patients spent 2.9 months extra in LDA or remission in the biomarker strategy compared with usual care T2T over 48 months. Total costs were €43 301 and €42 568 for, respectively, the usual care and biomarker strategy, and treatment costs accounted for 91% of total costs in both scenarios. Cost savings were driven due to patients in the biomarker strategy experiencing remission or LDA earlier, and starting tapering sooner. Cost-effectiveness was not so much driven by costs or test characteristics of the biomarker (scenario 1/2), but rather by the level of early and proactive tapering and drug costs (scenarios 3/4). CONCLUSIONS: The use of a biomarker for prediction of response to b/tsDMARD treatment in RA can be of added value to current treat-to-target clinical care. However, gains in efficacy are modest and cost gains are depending on a combination of early proactive tapering and high medication costs.

Extra-articular findings with FDG-PET/CT in rheumatoid arthritis patients: more harm than benefit.

Objective: Whole-body PET with CT scanning using 18F-fluorodeoxyglucose (18F-FDG) is used occasionally in RA patients to detect arthritis. FDG-PET/CT might also detect malignancies, but the amount of incidental findings and the number of relevant malignant diseases that could be missed are currently unknown. We aimed to study the malignancy screening performance of whole-body FDG-PET/CT in longstanding RA patients with low disease activity. Methods: FDG-PET/CT scanning was done in the intervention arm of the Dose REduction Strategy of Subcutaneous TNF-inhibitors (DRESS) study, a randomized controlled trial on dose-tapering of biological DMARDs. The reference standard was clinical diagnosis of malignancy during the 3-year follow-up period of the study. Prevalence of extra-articular abnormalities, follow-up and treatments were summarized post hoc. Results: One hundred and twenty-one scans were carried out in 79 patients. Extra-articular abnormalities were found in 59 of 121 (49%) scans, resulting in additional diagnostic procedures in 21 of 79 (26.6%) patients. Nine patients (7.4%) were suspected of malignancy; none turned out to be malignant. Six clinical malignancies that developed during follow-up were all negative on baseline FDG-PET/CT. Conclusion: Whole-body FDG-PET/CT scanning used in RA patients for imaging of arthritis results in frequent incidental extra-articular findings, whereas some who apparently had normal scans also developed malignancies. Trial registration: Netherlands Trial Register, www.trialregister.nl, NL6771.

Therapeutic drug monitoring of adalimumab in RA: no predictive value of adalimumab serum levels and anti-adalimumab antibodies for prediction of response to the next bDMARD.

BACKGROUND: After adalimumab treatment failure, tumour necrosis factor inhibition (TNFi) and non-TNFi biological disease-modifying anti-rheumatic drugs (bDMARDs) are equally viable options on a group level as subsequent treatment in rheumatoid arthritis (RA) based on the current best evidence synthesis. However, preliminary data suggest that anti-adalimumab antibodies (anti-drug antibodies, ADA) and adalimumab serum levels (ADL) during treatment predict response to a TNFi as subsequent treatment. OBJECTIVE: To validate the association of presence of ADA and/or low ADL with response to a subsequent TNFi bDMARD or non-TNFi bDMARD. Sub-analyses were performed for primary and secondary non-responders. METHODS: A diagnostic test accuracy retrospective cohort study was done in consenting RA patients who discontinued adalimumab after >3 months of treatment due to inefficacy and started another bDMARD. Inclusion criteria included the availability of (random timed) serum samples between ≥8 weeks after start and ≤2 weeks after discontinuation of adalimumab, and clinical outcome measurements Disease Activity Score in 28 joints - C-reactive protein (DAS28-CRP) between 3 to 6 months after treatment switch. Test characteristics for EULAR (European League Against Rheumatism) good response (DAS28-CRP based) after treatment with the next (non-)TNFi bDMARD were assessed using area under the receiver operating characteristic and sensitivity/specificity. RESULTS: 137 patients were included. ADA presence was not predictive for response in switchers to a TNFi (sensitivity/specificity 18%/75%) or a non-TNFi (sensitivity/specificity 33%/70%). The same was true for ADL levels in patients that switched to a TNFi (sensitivity/specificity 50%/52%) and patients that switched to a non-TNFi (sensitivity/specificity 32%/69%). Predictive value of ADA and ADL were similar for both primary and secondary non-responders to adalimumab. CONCLUSIONS: In contrast to earlier research, we could not find predictive value for response to a second TNFi or non-TNFi for either ADA or random timed ADL.