METHODS: A multiplex analytic microarray system was used to analyze the occurrence of antibodies to 10 different citrullinated peptides (filaggrin [fil307-324], vimentin [Vim2-17, Vim60-75], fibrinogen [Fibα563-583, Fibα580-600, Fibβ36-52, Fibβ62-81a, Fibβ62-81b], enolase [Eno5-21], and type II collagen [CitCII355-378]) in serum samples from 4,089 RA patients (1,231 Malaysian and 2,858 Swedish) and 827 healthy control subjects (249 Malaysian and 578 Swedish). The positive reaction threshold for each peptide was set separately for each population based on a specificity of 98%.
RESULTS: Distinct differences in the frequencies of 5 ACPA fine specificities (Vim60-75, Vim2-17, Fibβ62-81b, Eno5-21, and CitCII355-378) were found between the Malaysian and Swedish RA populations, despite a nearly identical percentage of patients in each population who were positive for anti-cyclic citrullinated peptide 2 antibodies. In Malaysian RA patients compared with Swedish RA patients, the frequencies of antibodies to Vim60-75 (54% versus 44%, corrected P [Pcorr ] = 1.06 × 10-8 ) and CitCII355-378 (17% versus 13%, Pcorr = 0.02) were significantly higher, while the frequencies of antibodies to Vim2-17 (25% versus 32%, Pcorr = 1.91 × 10-4 ), Fibβ62-81b (15% versus 30%, Pcorr = 2.47 × 10-22 ), and Eno5-21 (23% versus 50%, Pcorr = 3.64 × 10-57 ) were significantly lower.
CONCLUSION: Serum ACPA fine specificities differ between RA patients in different populations, although the total proportions of individuals positive for ACPAs are similar. Differing patterns of ACPA fine specificity could be attributed to variations in genetic and/or environmental factors.
MATERIALS AND METHODS: A search of relevant literature from 2014 to 2016 concerning targeted therapies in RA was conducted. The RA Update Working Group evaluated the evidence and proposed updated recommendations using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach, to describe the quality of evidence and strength of recommendations. Recommendations were finalized through consensus using the Delphi technique.
RESULTS: This update provides 16 RA treatment recommendations based on current best evidence and expert clinical opinion. Recommendations 1-3 deal with the use of conventional synthetic disease-modifying antirheumatic drugs. The next three recommendations (4-6) cover the need for screening and management of infections and comorbid conditions prior to starting targeted therapy, while the following seven recommendations focus on use of these agents. We address choice of targeted therapy, switch, tapering and discontinuation. The last three recommendations elaborate on targeted therapy for RA in special situations such as pregnancy, cancer, and major surgery.
CONCLUSION: Rheumatoid arthritis remains a significant health problem in the Asia-Pacific region. Patients with RA can benefit from the availability of effective targeted therapies, and these updated recommendations provide clinicians with guidance on their use.