Background Better outcomes are achieved by using a “tight” control strategy to treat rheumatoid arthritis (RA), but this approach has not yet been explored in resource-contrained sub-Saharan Africa. Utilizing the Clinical Disease Activity Index (CDAI) score, thus obviating the need for acute phase reactant measurement, may be a resource-sparing approach.
Objectives We prospectively compared the disease control with a tight control strategy utilising either the Simplified Disease Activity Index (SDAI) or the CDAI.
Methods In a 26-week study, 97 DMARD-naïve RA patients attending Chris Hani Baragwanath Hospital in 2011-12, were randomised to either an SDAI or CDAI arm and treated with traditional DMARDs, escalated on a monthly basis according to pre-defined protocol to achieve low disease activity (LDA). The primary outcome was the number of patients achieving at least LDA in both arms as by the DAS28. Additionally, the outcomes of entire cohort were compared to a cohort of 145 early RA patients attending the same hospital between 2005 and 2009 and treated with traditional DMARDs according to routine care1. No patients received biologic therapy.
Results The two arms were well-matched for disease activity and symptom duration at baseline (see table). At 26 weeks, neither the mean DAS28 score nor the proportion of patients achieving LDA was signficantly different beween the CDAI and SDAI groups. All patients received low dose prednisone (7.5mg daily) and at 26 weeks the mean methotrexate (MTX) dose was 20.8mg/week. Compared to the historical cohort treated with routine care, patients in the present study achieved a significantly lower mean DAS28, despite a signficantly longer symptom duration before commencement of DMARDs. Remission was achieved in 29% of patients treated by tight control, compared to 8% in the routine care group (p<0.0001, OR=4.6;SD 2.2-9.4). The historical cohort had significantly less exposure to low dose prednisone (52%, p<0.0001) and the majority (91%) received MTX, with a mean dose of 17.1mg/week at 26 weeks, significantly less than prescribed in the tight control group.
Conclusions In a resource-constrained setting, the less costly CDAI is an acceptable alternative to the SDAI in measuring disease activity. A tight control strategy improves disease control in the short-term. Further follow-up is necessary to see whether the better outcome is sustained in the longer term.
Hodkinson B et al. Clin Rheumatol (2012) 31:613–619
Acknowledgements This study was funded by the Carnegie Corporation and the University of the Witwatersrand Connective Tissue Diseases Research Fund
Disclosure of Interest None Declared