To characterize disease activity patterns in a large cohort of children with juvenile idiopathic arthritis (JIA), by applying newly developed preliminary definitions of inactive disease, clinical remission on medication, and clinical remission off medication.
Children with persistent or extended oligoarthritis, polyarthritis (either rheumatoid factor [RF] positive or RF negative), or systemic JIA who had been followed up for a period of at least 4 years were evaluated for episodes of inactive disease, clinical remission on medication, and clinical remission off medication. Descriptive statistics, correlation analyses, and survival analyses were performed.
Four hundred thirty-seven children met the criteria for review. Three hundred ninety-one patients (89%) experienced a total of 878 episodes of inactive disease, with a median episode length of 12.7 months. Two hundred twenty-eight episodes of inactive disease (26%) resulted in clinical remission off medication; it was equally as likely that episodes of inactive disease would or would not follow a period of clinical remission on medication. Thirty-six percent of episodes of clinical remission off medication persisted for at least 2 years, and only 6% of such episodes persisted for 5 years. RF-positive patients were the least likely to achieve clinical remission off medication (5%), and patients with persistent oligoarticular JIA were the most likely (68%). Among patients with persistent oligoarticular JIA, most of the disease course was characterized by inactive disease; in most other patients the majority of the disease course involved active disease.
Using newly developed preliminary criteria for inactive disease, clinical remission on medication, and clinical remission off medication, we observed that only one-fourth of 878 episodes of inactive disease resulted in clinical remission off medication during followup of at least 4 years. Only a small proportion of episodes of clinical remission off medication were sustained for >5 years. These results highlight the critical need for therapies that have the ability to induce sustained remission of JIA.