Objective: The introduction of effective treatment strategies in the past two decades has changed the management of RA dramatically. The objective was to analyse the changes in disease activity, function, joint damage and incidence of orthopaedic surgery over a period of 20 years (1989-2009) for patients with RA.
Methods: Data acquired from 1989 to 2008 inclusive from the Nijmegen RA inception cohort were studied. By repeated measures analysis the course of the population mean disease activity score (DAS28) and the Health Assessment Questionnaire-Disability Index (HAQ-DI) corrected for age, gender, RF and disease duration was determined. Orthopaedic interventions were analysed as incidence rates with a Poisson distribution. We calculated the prevalence of the various therapies that patients were receiving.
Results: By 2009, 992 patients with RA had been included and 273 had been excluded. From 1989 onwards, the proportion of patients using MTX increased from 5% (8 of 164) to 62% (486 of 780), and biologic response modifiers from 0% to 22% (168 of 780) in 2008. The average MTX dosage increased to 16.1 ± 5.5 mg/week in 2008. The mean DAS28 (3.1) and HAQ-DI (0.47) were least (P < 0.008) in 2008 compared with previous years. There was a significant trend towards lower incidence rates of orthopaedic intervention in the period 2006-2008 than in almost all previous years.
Conclusion: Treatment strategy changed in a large inception cohort of patients with RA which coincided with decreased disease activity, increased functional ability and fewer orthopaedic interventions since the early 1990s.
Keywords: DMARD treatment; biologic agents; epidemiology; inception cohort; methotrexate; observational study; rheumatoid arthritis; time trends.