How reliable is the diagnosis of very early rheumatoid arthritis in the multicentre real life prospective study as a predictor of remission?
Dear Editor, Gremese et al. conclude from the real life prospective study performed in three early arthritis clinics that 12 weeks disease duration and an early intervention with DMARD represent the most significant opportunities to reach remission of RA. Moreover, it is supposed that vera early rheumatoid arthritis (VERA) represents a window of opportunity in terms of cost saving.
A high level of confidence in the diagnosis of RA early in its course
is mandatory for the validity of any study. But experts often disagree
about diagnoses and discrepancies may be considerable among
rheumatologists confronted with early arthritis . In the present
observational study all the subjects diagnosed as having early RA and VERA
fulfilled the 1987 classification criteria for RA at the first visit and
also retrospectively met the new 2010 RA classification criteria.
Notwithstanding misclassification may be an important confounder which
might have affected the results significantly. Multiple studies recently
indicated that the 2010 RA classification criteria have a considerable
risk of false positive and false negative classification of early
arthritis as RA . In the present study 148 (20.8%) of 711 subjects
initially diagnosed with RA were classified as VERA. It is striking that
the subjects collected in the early arthritis cohort 2 (EAC 2) were
positive for rheumatoid factor and anti-CCP in only 35.7% and 26.7%,
respectively. How many of the subjects in the follow-up with VERA were
collected from EAC 2? Moreover, it would be interesting to know how many
of the subjects with VERA who had a follow-up assessment were positive for
rheumatoid factor and/or anti-CCP in each of the three EAC. Were all
patients tested for HLA-B27? A proportion of patients with early
undifferentiated arthritis (UA) , particularly patients with
oligoarthritis, may have reactive arthritis (ReA) despite not having a
clear history of preceding infection [3 ]. In these cases, a thorough
search for offending organisms may be crucial.
Additionally, sero-negative early arthritis and UA very frequently go into spontaneous remission over weeks and months. Estimates of prognosis from studies specifically reporting outcomes for UA suggest that up to 60% of UA patients experience remission and 10% to 40% have persistent disease activity, but remain undifferentiated . Therefore, such cases misclassified as RA might distort the results of the multivariate logistic regression in which VERA and DMARD treatment emerged as predictors of remission.
Altogether, it will be of critical importance for the judgment of the validity of the present study to learn more how the issues referred where addressed by the authors?
References 1.Berthelot JM, Klarlund M, McGonagle D et al. Lessons from an international survey of paper cases of 10 real patients from an early arthritis clinic. CRI (Club Rhumatismes et Inflammation) Group. J Rheumatol 2001;28:975-81. 2.Zeidler H. The need to better classify and diagnose early and very early rheumatoid arthritis. J Rheumatol. 2012;39:212-7. 3.Hitchon CA, Peschken CA, Shaikh S, El-Gabalawy HS. Early undifferentiated arthritis. Rheum Dis Clin North Am 2005;31:605-26.
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