A comparison of disease burden in rheumatoid arthritis, psoriatic arthritis and axial spondyloarthritis.

OBJECTIVE: The main objective of this study was to compare disease burden in rheumatoid arthritis (RA), psoriatic arthritis (PsA) and axial spondyloarthritis (ax-SpA). METHODS: In this cross-sectional study, all the RA (1093), PsA (365) and ax-SpA (333) patients who visited the out-patient clinic of the Hospital of Southern Norway Trust during the year 2013 were included; the RA patients all had a RA diagnosis verified by the treating rheumatologist, the PsA patients all fulfilled the ClASsification for Psoriatic ARthritis (CASPAR) criteria and the ax-SpA patients all fulfilled the Assessment of SpondyloArthritis international Society (ASAS) classification criteria for ax-SpA. Patient-reported health status, demographic variables, medications, and composite scores of disease activity were assessed. The main analyses were performed using General Linear Models adjusted for age, sex and multiple comparisons. Correlation analyses were performed using Spearman's rho. RESULTS: The reported pain, joint pain, patient's global assessment and fatigue were similar in PsA and ax-SpA, but significantly lower in RA. The 28-joint Disease Activity Score (DAS28) (0.3±0.1, p = 0.003), Clinical Disease Activity Index (CDAI) (1.0±0.4, p = 0.028) and Routine Assessment of Patient Index Data 3 (RAPID3) (0.4±0.1, p = 0.004) were all significantly higher in PsA vs. RA. RAPID3 showed moderate to high correlation with DAS28 (rho = 0.521, p<0.001) and CDAI (rho = 0.768, p<0.001) in RA and PsA, and with Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) (rho = 0.902, p<0.001) and Bath Ankylosing Spondylitis Functional Index (BASFI) (0.865, p<0.001) in ax-SpA and PsA. CONCLUSION: In conclusion, patient- reported outcome measures were similar in our population of PsA and ax-SpA patients, but significantly lower for the RA patients. Composite disease activity measures were lower in RA than in PsA and ax-SpA, but the magnitude of these differences was small and probably not of clinical significance. Our study indicates that disease burden in RA, PsA and ax-SpA may be more similar than previously demonstrated.

Lyme arthritis in Southern Norway--an endemic area for Lyme borreliosis.

BACKGROUND: Despite Southern Norway is an endemic area for Lyme borreliosis there is a lack of data on Lyme arthritis (LA). In the literature controversies exist if acute LA can develop into chronic arthritis. Our objective was to identify and characterize patients with LA in Southern Norway and explore disease course after antibiotic treatment. METHODS: Patients aged 20 years or older with arthritis and a positive serology for Borrelia burgdorferi infection (IgG and/or IgM) suspected of having LA were consecutively recruited either from general practitioners or from hospital departments. RESULTS: From January 2007 to December 2010 a total of 27 patients were assessed. Mean (range) age was 56 years (41-80) and mean symptom duration prior to inclusion was 11.2 weeks (1 day-2 years). Definite LA was diagnosed in 16 patients, probable LA in 5 patients and 6 patients were concluded to have other arthritis disorders. Among the 21 LA patients 20 had mono-arthritis (knee 18, ankle 2) and 1 had polyarthritis.All LA patients responded favourable to antibiotic treatment and none of the patients developed chronic arthritis after long term follow up, not even in LA patients who had intraarticular glucocorticosteroid (GC) injection prior to antibiotic treatment. CONCLUSIONS: Our data shows that LA in Southern Norway is a benign disease which successfully can be treated with antibiotics even in patients treated with GC prior to antibiotics.