Non-adherence to subcutaneous biological medication in patients with rheumatoid arthritis: a multicentre, non-interventional study

Objective To evaluate non-adherence to prescribed subcutaneous biologicals in rheumatoid arthritis (RA) patients in Spain. Methods ARCO (Study on Adherence of Rheumatoid Arthritis patients to SubCutaneous and Oral Drugs) was a multicentre, non-interventional retrospective study involving 42 rheumatology clinics from representative hospitals throughout Spain. The primary objective was to assess the percentage of patients (aged >= 18 years with an established RA diagnosis) with non-adherence to prescribed subcutaneous biologicals using clinical records and hospital pharmacy dispensing logs as the primary information sources. Adherence was assessed using the Medication Possession Ratio (MPR). Additionally, patients completed the Morisky-Green Medication Adherence Questionnaire. Results A total of 364 patients (77.5% females, mean age 54.9 years, median RA duration since diagnosis 7.8 years) were enrolled in ARCO. Non-adherence (MPR