Disease course, outcome, and predictors of outcome in a population-based juvenile chronic arthritis cohort followed for 17 years.

OBJECTIVE: To investigate disease course, outcome, and predictors of outcome in an unselected population-based cohort of individuals diagnosed with juvenile chronic arthritis (JCA) followed for 17 years. METHODS: The cohort consisted of 132 incidence JCA cases identified 1984-1986 according to EULAR criteria. At 5-year followup, 129 individuals underwent joint assessment, laboratory measurements, radiographic examination, and medication and functional assessment. At 17-year followup, 86 were examined with joint assessment, laboratory measurements, medication assessment, Health Assessment Questionnaire (HAQ), Keitel functional test (KFT), and Medical Outcomes Study Short Form-36 (SF-36). RESULTS: At 17-year followup, 40% were in remission, 44% changed subgroups, median HAQ score was 0.0 (range 0.0-1.5), and median KFT was 100 (range 54-100). SF-36 scores were significantly lower compared to a reference group. Thirty-nine percent of those in remission at 5-year followup were not in remission at 17-year followup. In multivariate analyses of variables from the 17-year followup: remission was predicted by remission at 5-year followup (OR 4.8); HAQ > 0 by rheumatoid factor (RF)-positivity at 5-year followup (OR 3.6); KFT < 100 by nonremission (OR 11.3); and RF-positivity (OR 5.6) at 5-year followup; and the SF-36 physical component summary score above average of the reference group by remission at 5-year followup (OR 5.8). CONCLUSION: This longterm study of 86 individuals with JCA showed large variability of disease courses and of impaired health-related quality of life. Sixty percent were not in remission at 17-year followup. Longterm outcome was best predicted by and associated with characteristics at 5-year followup rather than those at onset.

Time-dependent increase in risk of hospitalisation with infection among Swedish RA patients treated with TNF antagonists.

OBJECTIVES: The degree to which treatment with tumour necrosis factor (TNF) antagonists may be associated with increased risks for serious infections is unclear. An observational cohort study was performed using prospectively collected data from the Swedish Biologics Register (ARTIS) and other national Swedish registers. METHODS: First, in the ARTIS, all 4167 rheumatoid arthritis (RA) patients starting TNF antagonist treatment between 1999 and 2003 were identified. Secondly, in the Swedish Inpatient Register, all individuals hospitalised for any reason and who also carried a diagnosis of RA, between 1964 and 2003 (n = 44 946 of whom 2692 also occurred in ARTIS), were identified. Thirdly, in the Swedish Inpatient Register, all hospitalisations listing an infection between 1999 and 2003 were identified. By cross-referencing these three data sets, RRs for hospitalisation with infection associated with TNF antagonist treatment were calculated within the cohort of 44 946 RA patients, using Cox regression taking sex, age, geography, co-morbidity and use of inpatient care into account. RESULTS: Among the 4167 patients treated with TNF antagonists, 367 hospitalisations with infections occurred during 7776 person-years. Within the cohort of 44 496 RA patients, the RR for infection associated with TNF antagonists was 1.43 (95% CI 1.18 to 1.73) during the first year of treatment, 1.15 (95% CI 0.88 to 1.51) during the second year of treatment, and 0.82 (95% CI 0.62 to 1.08) for subjects remaining on their first TNF antagonist treatment after 2 years. CONCLUSION: Treatment with TNF antagonists may be associated with a small to moderate increase in risk of hospitalisation with infection, which disappears with increasing treatment duration.

Risk and case characteristics of tuberculosis in rheumatoid arthritis associated with tumor necrosis factor antagonists in Sweden.

OBJECTIVE: Because treatment with tumor necrosis factor (TNF) antagonists may increase the risk of tuberculosis (TB), and because knowledge of the risk of TB in rheumatoid arthritis (RA) not treated with biologics is scarce and of uncertain generalizability to low-risk populations, this study sought to determine the risk of TB among Swedish patients with RA. METHODS: Using data from Swedish nationwide and population-based registers and data from an ongoing monitoring program of TNF antagonists, the relative risks of TB in patients with RA (versus the general population) and of TB associated with TNF antagonists (versus RA patients not treated with biologics) were determined by comparing the incidence of hospitalization for TB in 3 RA cohorts and 2 general population cohorts from 1999 to 2001. We also reviewed the characteristics of all reported cases of TB in RA patients treated with TNF antagonists in Sweden and calculated the incidence of TB per type of TNF antagonist between 1999 and 2004. RESULTS: During 1999-2001, RA patients who were not treated with TNF antagonists were at increased risk of TB versus the general population (relative risk 2.0, 95% confidence interval [95% CI] 1.2-3.4). RA patients treated with TNF antagonists had a 4-fold increased risk of TB (relative risk 4.0, 95% CI 1.3-12) versus RA patients not treated with TNF antagonists. The reported TB cases during 1999-2004 in RA patients exposed to TNF antagonists (9 infliximab, 4 etanercept, 2 both) were predominantly pulmonary. TB occurred up to 3 years following the start of treatment. CONCLUSION: Irrespective of whether TNF antagonists are administered, Swedish patients with RA are at increased risk of TB. During 1999-2001, TNF antagonists were associated with an increased risk of TB, up to 4-fold in magnitude. This increased risk may persist over time during treatment and is related to both infliximab and etanercept.