Can baseline serum microRNAs predict response to TNF-alpha inhibitors in rheumatoid arthritis?

BACKGROUND: In rheumatoid arthritis, prediction of response to TNF-alpha inhibitor (TNFi) treatment would be of clinical value. This study aims to discover miRNAs that predict response and aims to replicate results of two previous studies addressing this topic. METHODS: From the observational BiOCURA cohort, 40 adalimumab- (ADA) and 40 etanercept- (ETN) treated patients were selected to enter the discovery cohort and baseline serum profiling on 758 miRNAs was performed. The added value of univariately selected miRNAs (p < 0.05) over clinical parameters in prediction of response was determined by means of the area under the receiver operating characteristic curve (AUC-ROC). Validation was performed by TaqMan single qPCR assays in 40 new patients. RESULTS: Expression of miR-99a and miR-143 predicted response to ADA, and miR-23a and miR-197 predicted response to ETN. The addition of miRNAs increased the AUC-ROC of a model containing only clinical parameters for ADA (0.75 to 0.97) and ETN (0.68 to 0.78). In validation, none of the selected miRNAs significantly predicted response. miR-23a was the only overlapping miRNA compared to the two previous studies, however inversely related with response in one of these studies. The reasons for the inability to replicate previously proposed miRNAs predicting response to TNFi and replicate those from the discovery cohort were investigated and discussed. CONCLUSIONS: To date, no miRNA consistently predicting response to TNFi therapy in RA has been identified. Future studies on this topic should meet a minimum of standards in design that are addressed in this study, in order to increase the reproducibility.

Tuberculosis during TNF-α inhibitor therapy, despite screening.

As part of a prospective study on the safety of TNF-α inhibitor therapy after screening for and treatment of latent tuberculosis infection (LTBI), we report two patients who developed active tuberculosis (TB) infection during TNF-α inhibitor therapy, despite negative screening for LTBI. The clinical history is suggestive of a primary infection acquired during travelling to TB-endemic countries. In this lesson of the month we would like to highlight the risk of travelling to TB-endemic areas in patients treated with TNF-α inhibitor therapy. Screening for latent tuberculosis infection is not enough to prevent tuberculosis in patients treated with TNF-α inhibitor therapy.

Look beyond the disease activity score of 28 joints (DAS28): tender points influence the DAS28 in patients with rheumatoid arthritis.

OBJECTIVE: To explore the influence of tender points (TP) on the Disease Activity Score assessing 28 joints (DAS28) in patients with rheumatoid arthritis (RA). METHODS: In 200 consecutive patients with RA from the outpatient clinic, DAS28 and its components, tender and swollen joint counts (TJC, SJC, respectively), visual analog scale (VAS) for patient's general health (GH), and erythrocyte sedimentation rate (ESR), along with a tender point count (TPC) were assessed. Patients were categorized according to 4 TPC classes: zero, 1-5, 6-10, and ≥ 11 TP. The influence of TPC classes on DAS28 and its individual components was determined with Kruskal-Wallis tests and correlations between TP and DAS28 and its components were calculated. RESULTS: In 196 eligible patients, 70% were female, mean age was 59 years, and median disease duration was 3.9 years; median DAS28 was 3.1; and 49% had active disease, defined as DAS28 > 3.2. In 15% of patients, the TPC was ≥ 11, in 12% 6-10, in 30% 1-5, and in 43% zero. TPC significantly influenced the DAS28 and its less objective components TJC and VAS-GH (i.e., based on patient's report), but not the more objective DAS28 components SJC and ESR (i.e., observer- and laboratory-based). CONCLUSION: DAS28 is influenced by tender points, even in the non-fibromyalgia range, falsely suggesting higher disease activity and decreasing the sensitivity of the DAS28 criterion of low disease activity or remission. When applying DAS28-guided "tight control" or "treat-to-target" treatment strategies in RA, evaluation of not only the DAS28, but also its individual components along with a full joint and physical evaluation including assessment of TP is required to reliably estimate the individual's disease activity, which guides therapeutic decisions.