OBJECTIVES: RA is a chronic disease associated with a significant use of health care resources, imposing a substantial economic burden to patients, health insurance and to society in France. The objective of the present study was to assess the use of direct medical resources excluding drug costs by RA patients in France and to derive original costing data per level of disease activity.METHODS: An advanced standard costing approach was performed in collaboration with a panel of expert clinicians highly experienced in the management of RA in France. Four categories of disease activity were defined according to DAS28 thresholds: patients (pts) achieving remission (DAS <2.6), pts not achieving remission (DAS ≥2.6), pts achieving low disease activity state (LDAS; DAS ≤3.2) and pts not achieving LDAS (DAS >3.2). Eight resource utilization items were defined: medical visits, laboratory tests, hospitalization, imaging, physiotherapy, nursing, adaptive aids and transportation. Resource utilization and unit costs from the national payer perspective were collected and simulated using distribution ranges for each item. Using a simulation model, a computation of all costs distributions was performed to estimate the overall costs per six months over a 2-year time horizon.RESULTS: Direct medical costs were estimated per disease activity level. For pts achieving remission during the first 6 months, about 90% generated costs under € 1000, with costs estimated at €771 (SD=199) per 6 months and €511 (SD=162) for each subsequent 6 months (p<0.001). For pts not achieving remission per 6 months, about 85% generated costs under € 1500, with costs estimated at €1159 per 6 months (SD=339). For pts achieving LDAS, costs were estimated at €905 (SD=263) per 6 months and €696 (SD=240) for each subsequent 6 months (p<0.001). For pts not achieving LDAS, costs were estimated at €1215 per 6 months (SD=405). Key costs drivers were medical visits, laboratory tests and transportation. CONCLUSIONS:This cost of illness assessment provides precise and current estimates of medical direct costs per RA disease activity in France, confirming that RA imposes a substantial economic burden. The findings suggest that achieving LDAS or remission is associated with substantially lower RA medical costs.