POS1066 WHERE HAVE ALL THE RHEUMATOID NODULES GONE?

Abstract

BackgroundThe most common extraarticular manifestation of rheumatoid arthritis (RA) is the rheumatoid nodule, which is reported to affect about 30% of patients with RA.[1]The development of rheumatoid nodules has been associated most strongly with high disease activity, seropositive status, and more rapid progression of joint destruction. Despite significant changes in RA treatment and decreasing incidence of seropositive RA, no recent population-based studies have assessed the epidemiology of rheumatoid nodules.ObjectivesWe aim to investigate changes in rheumatoid nodule incidence over time.MethodsThis study evaluated rheumatoid nodule incidence trends using an inception cohort that included all adult patients from a geographically well-defined area who met the 1987 American College of Rheumatology criteria for RA between 1/1/1985 and 12/31/2014. Patients were followed until the earlier of death, migration from the region, or 12/31/2000 (for patients with incident RA in 1985-1994) or 12/31/2008 (for 1995-2007 patients) or 10/15/2022 (for 2008-2014 patients). Patients were divided into two cohorts based on the incidence date of RA, an early cohort from 1985-1999 and a later cohort from 2000-2014. Medical records were reviewed manually, and the incidence date of rheumatoid nodules was recorded if determined to be present either by clinical judgment and/or histopathology. The 10-year cumulative incidence of rheumatoid nodules was estimated in each cohort. Cox proportional hazard models adjusted for age, sex and calendar year were used to determine associations between specific demographic and RA disease data with rheumatoid nodules.Results907 patients were included in this study, 296 (67% female) in the 1985-1999 cohort and 611 (70% female) in the 2000-2014 cohort. The mean follow-up period between these cohorts, respectively, was 9.1 and 7.4 years. Baseline characteristics (earlier cohort, latter cohort) included rheumatoid factor (RF) positive (70%, 59%), joint erosions in the first year of RA (24%, 29%), and ever smoker (57%, 47%). The 10-year cumulative incidence of rheumatoid nodules was 31% in the 1985-1999 cohort and 16% in the 2000-2014 cohort (hazard ratio [HR] 0.52, 95% confidence interval [CI] 0.39-0.70). Identified risk factors for the development of rheumatoid nodules included RF positivity (HR 4.38, 95%CI 2.37-8.09), erosions (HR 2.53, 95%CI 1.64-3.91), current smoker (HR 2.09, 95%CI 1.30-3.37), male sex (HR 1.77, 95%CI 1.14-2.73), methotrexate use (HR 1.77, 95%CI 1.09-2.86) and other DMARDs (HR 2.07, 95%CI 1.14-3.74) (Table 1).ConclusionThe incidence of rheumatoid nodules has decreased substantially over time. More research is needed to understand the drivers of this improvement and implications on RA disease outcomes.Reference[1] Myasoedova E, Crowson CS, Turesson C, Gabriel SE, Matteson EL. Incidence of extraarticular rheumatoid arthritis in Olmsted County, Minnesota, in 1995-2007 versus 1985-1994: a population-based study. J Rheumatol. 2011;38(6):983-989.Table 1.Risk factors associated with rheumatoid nodules in the 2000-2014 cohort.VariableRheumatoid Nodules HR (95% CI)Age (per 10-year increase)0.95 (0.82, 1.09)Male sex1.77 (1.14, 2.73)Calendar year of RA incidence0.88 (0.84, 0.93)Cigarette smoking at baseline Ever1.38 (0.90, 2.13) Current2.09 (1.30, 3.37)BMI (per 1kg/m2increase) baseline1.00 (0.97, 1.04)RF positivity4.38 (2.37, 8.09)Highest ESR in the 1styear of RA (per 10 mm/h increase)1.03 (0.95, 1.12)Erosions/destructive changes on radiographs2.53 (1.64, 3.91)Medication usage Methotrexate1.77 (1.09, 2.86) Hydroxychloroquine0.95 (0.61, 1.49) Other DMARD2.07 (1.14, 3.74) Biologic response modifiers1.64 (0.87, 3.11) Corticosteroids (systemic)1.11 (0.69, 1.77)*Adjusted for age, sex, and calendar year.**RA, rheumatoid arthritis; BMI, body mass index; RF, rheumatoid factor; ESR, erythrocyte sedimentation rate; DMARD, disease-modifying antirheumatic drugAcknowledgements:NIL.Disclosure of InterestsNone Declared.