POS0287 USE OF BIOLOGIC DISEASE MODIFYING ANTI-RHEUMATIC DRUGS IN RELATION TO THE RISK OF LYMPHOMA: A COHORT STUDY OF US VETERANS WITH RHEUMATOID ARTHRITIS

Abstract

Background:Epidemiologic studies suggest that disease duration and degree of inflammatory activity of rheumatoid arthritis (RA) contribute to lymphoma development. However, the association of the use of biologic disease modifying anti-rheumatic drugs (bDMARDs) in patients with RA on lymphoma risk needs further evaluation.Objectives:Examine the effect of administration of bDMARDS on the incidence of lymphoma in an inception cohort of RA.Methods:We identified patients diagnosed with RA in any US Veterans Affairs (VA) facility from 1/1/2002 and 12/31/2018 using the Veteran’s Health Administration (VHA) databases. To be included, each patient was required to meet the following criteria: 1) 2+ RA diagnostic codes at least 7 days apart but no more than 365 days apart 2) a prescription for a conventional synthetic DMARD (csDMARD) within 90 days of the first RA diagnosis 3) One inpatient or outpatient visit 30 days to 2 years preceding first RA diagnosis (indicating they are a regular user of the VHA). We excluded patients for any of the following if they preceded the first RA diagnosis: 1) a prior single RA diagnostic code 2) a prescription for any DMARD medication 3) a concomitant diagnosis of another inflammatory arthritis (e.g. psoriatic arthropathy) 4) a diagnosis of lymphoma. Index date for the study is the date of the first qualifying RA diagnosis. Lymphoma diagnoses were identified through VHA records using the International Classification of Diseases-Oncology codes.Results:We identified 27,536 veterans with RA in the study period meeting the inclusion and exclusion criteria. Of these, 53% (n=14,705) were in the age range 60 to 80 years. The cohort was 89% male, 75.5% White, 13.7% African American. Over the study period, 1.2% (n=332) of the study population developed a lymphoma.Conclusion:Using the nationwide VHA we have identified a large inception cohort of patients with RA of whom 1.2% developed lymphoma over study follow-up. This data will be used in future analyses to produce estimates of the effect of biologic medications on lymphoma risk, adjusting for confounding by indication and other variables.Table 1.Baseline characteristics of the cohort based on bDMARD exposure statusCharacteristicbDMARD-naive (n= 19,095)bDMARD-exposed (n=8,441)Overall Lymphomas Age (years)171161 18-4046 40-606378 60-8010074 >8043 Males17,206 (90%)7,270 (86%)Race White14,150 (74%)6,627 (76%) Black2,674 (14%)1,090 (13%) Asian96 (0.5%)46 (0.5%) Native American or Pacific Islander371 (2%)187 (2.2%) Missing1,804 (9%)491 (6%)Acknowledgements:The work in this abstract is supported by Investigator Award from the Rheumatology Research Foundation to Dr Singh.Disclosure of Interests:None declared