OBJECTIVES: Investigate the association between Disease Activity Score 28 C-Reactive Protein (DAS28-CRP) score, disease duration and patient costs in rheumatoid arthritis (RA) patients in Spain, using data from the Burden of Rheumatoid Arthritis across Europe: a Socioeconomic Survey (BRASS).

METHODS: Data were extracted from BRASS, a societal perspective observational RA dataset across 10 European countries (EU5, Denmark, Sweden, Hungary, Poland and Romania). In Spain, 93 RA specialising clinicians provided information on 911 adult patients; of these, 529 patients completed corresponding questionnaires about the burden of RA. Twelve-month costs captured included: consultations, testing, hospital admissions and procedures, payments to professional caregivers, travel costs, requirement for aids/equipment and informal care costs. Indirect costs captured from the patient included work productivity impact.

Multiple regression was used to investigate the association between disease duration, most recent DAS28-CRP score and total cost of patients excluding costs of conventional synthetic and biologic disease modifying drugs. Disease duration and DAS28-CRP score were modelled as explanatory variables against the total cost response variable, adjusted for covariates including age, gender and BMI.

RESULTS: Ordinary least squares (OLS) linear regression provided adequate fit and was carried out on 173 patients in Spain with complete information on severity and total cost. Both disease duration and DAS28-CRP score had a statistically significant association with total cost; a unit increase in DAS28 score meant a total cost increase of €2,971 (p=0.001), whereas a unit increase in disease duration of one year increased total cost by €341 (p=0.006), with confounders age, gender, BMI and either DAS28-CRP or duration held at mean values.

CONCLUSIONS: Results from econometric analysis suggest disease severity and duration of disease are associated with higher patient cost from a societal perspective.