Systematic DAS-Driven Therapy May Improve Outcomes in Rheumatoid Arthritis
January 4, 2010 — In patients with recent-onset rheumatoid arthritis receiving traditional treatment, treatment systematically driven by Disease Activity Score (DAS) was associated with significantly better clinical improvement and possibly with reduced progression of joint damage, according to the results of a study reported in the January 2010 issue of Annals of the Rheumatic Diseases.
"This study provides further evidence in support of the data that objective assessment of rheumatoid arthritis disease activity and using a goal to achieve a target disease activity state (such as low disease activity state or remission) to make therapeutic decisions leads to significant improvement in clinical outcomes for rheumatoid arthritis patients," Nasim A. Khan, MD, assistant professor of rheumatology at the University of Arkansas for Medical Sciences in Little Rock, told Medscape Rheumatology when asked for independent comment. "Unfortunately, most patients with rheumatoid arthritis in routine clinical care are not evaluated objectively for disease activity, and treatment decisions are made based on gestalt impressions of the treating doctor. This study provides further impetus to change such practices to improve clinical outcomes for rheumatoid arthritis patients."
The goal of this study, by Y.P.M. Goekoop-Ruiterman, from Leiden University Medical Centre in Leiden, the Netherlands, and colleagues, was to compare the efficacy of treatment systematically driven by DAS vs routine care in patients with recent-onset rheumatoid arthritis. Participants were receiving traditional antirheumatic therapy from either the BeSt study, a randomized controlled trial comparing different treatment strategies (group A; n = 234), or from 2 Early Arthritis Clinics (group B; n = 201).
Patients in group A had systematic, DAS-driven treatment adjustments aiming to achieve low disease activity, defined as DAS ≤ 2.4. Physician judgment determined treatment of patients in group B. Outcomes included functional ability measured with the Health Assessment Questionnaire (HAQ), Disease Activity Score in 28 joints (DAS28), and Sharp/van der Heijde radiographic score (SHS).
Demographic characteristics were similar in both groups, and mean baseline HAQ was 1.4. Compared with group B, group A had a longer median disease duration (0.5 vs 0.4 years; P = .016), higher mean DAS28 (6.1 vs 5.7; P < .001), more patients who tested positive for rheumatoid factor (66% vs 42%; P < .001), and more patients with erosions (71% vs 53%; P < .001).
After 1 year, mean HAQ improvement was 0.7 in group A and 0.5 in group B (P = .029), and the percentage in remission, defined as a DAS28 of less than 2.6, was 31% vs 18% (P <. 005), respectively. Median SHS progression in group A was 2.0 vs an expected progression of 7.0. In group B, median SHS progression was 1.0 vs an expected progression of 4.4.
"In patients with recent-onset rheumatoid arthritis receiving traditional treatment, systematic DAS-driven therapy results in significantly better clinical improvement and possibly improves the suppression of joint damage progression," the study authors write.
Strengths of this study noted by Dr. Khan are that 1-year follow-up data on all outcomes of interest were available for the vast majority of the study patients, DAS assessment was performed by trained research nurses, and radiographic progression assessment was done independently by 2 readers blinded to treatment group and sequence of films.
However, Dr. Khan also noted several study limitations.
"Despite similar enrollment criteria, the DAS-driven therapy group and routine care group differed significantly upon baseline assessment in rheumatoid arthritis disease activity and adverse prognostic factors (RF-positivity and radiographic joint damage)," he said.
Dr. Khan also noted significant differences in the medications received by patients in the 2 groups. Patients in the routine care group less often received methotrexate and more often received low-dose prednisone.
"Furthermore, it is not clear whether disease activity assessment by DAS or DAS28 was available or performed by the treating doctor at the time of therapeutic decision for the patients in the routine care group," Dr. Khan added. "These factors may have masked the true impact of DAS-driven therapy compared to routine care."
When asked about additional research needed, Dr. Khan pointed out that the 6 available indices of rheumatoid arthritis activity should be compared with one another. The American College of Rheumatology 2008 recommendations for the use of disease-modifying antirheumatic drugs suggest using any of the 6 indices to assess rheumatoid arthritis disease activity, but some of these indices have, at best, a moderate agreement with one another.
"While objective assessment of RA [rheumatoid arthritis] disease activity is important, it remains unclear which of the several indices that have been developed and validated for this purpose is optimum for patient care," Dr. Khan concludes. "Further research is needed to clarify the comparative utility and interchangeability of these indices and impact of factors such as comorbidity burden on rheumatoid arthritis activity assessment. Also, further studies are needed for the long term clinical effect of the radiographic progression observed with current treatments."
The Dutch College of Health Insurances (College Voor Zorgverzekeringen) funded this study, with additional funding provided by Schering-Plough, BV, and Centocor. Some of the study authors have disclosed various financial relationships with Schering-Plough. Dr. Khan has disclosed no relevant financial relationships.
Ann Rheum Dis. 2010;69:65-69. Abstract