The economic burden of moderate-to-severe rheumatoid arthritis in Spain: the CIARA study

Abstract

AIMS: The CIARA (Cost Impact Analysis in Rheumatoid Arthritis patients) study in Spain aimed to assess societal costs (?2022) associated with adult patients with moderate-to-severe rheumatoid arthritis (RA) starting advanced therapies after failing conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) or a first biologics (bDMARD). Costs included those incurred by the Spanish National Health System, indirect costs due to productivity losses, and patient out-of-pocket expenses. Secondary objectives were to compare costs according to patients' disease activity and treatment subgroups, identify variables associated with costs, and conduct a cost-utility analysis (CUA) of switching strategies. METHODS: This prospective, non-interventional, multicenter cohort included adults with active RA (Disease Activity Score in 28 joints with erythrocyte sedimentation rate ?3.2) starting a bDMARD or a targeted synthetic DMARD (tsDMARD) and followed for 12 months. Total and disaggregated mean costs per patient were estimated across three periods: 6 months before, and 0-to-6 months and 6-to-12 months post-switch. Costs for the 6-month pre-switch were compared with those for the 6-to-12 post-switch. RESULTS: A total of 118 patients (mean age: 54.9 years; 78% women) were included. Mean total cost per patient increased from ?6,882 pre-switch to ?9,927 at 6-12 months (+44.3%;p < 0.001), primarily driven by pharmacological costs (+191%), while out-of-pocket expenses (-55%;p = 0.001) and productivity losses (-25%;p = 0.394) decreased. Switching from a csDMARD was dominant vs. switching from a first bDMARD (-?11,281/quality-adjusted life year [QALY] gained). Patients who achieved remission at 12 months had lower costs than those with moderate-high activity. The Work Productivity and Activity Impairment (WPAI) productivity impairment subscale and patient satisfaction with care were independently associated with total costs. LIMITATIONS: Observational design, limited power for subgroups, official-actual price gap, and a 1-year horizon. CONCLUSIONS: Switching to advanced therapies reduced out-of-pocket expenses and productivity losses. Although this reduction did not offset higher pharmaceutical spending, it may reflect clinical improvements.