OP0277 PERSISTENT EXCESS OF STROKE EVENTS IN RHEUMATOID ARTHRITIS: A RETROSPECTIVE COHORT STUDY FROM HORDALAND, NORWAY FROM 1972 TO 2014

Abstract

BackgroundPatients with rheumatoid arthritis (RA) have an excess risk of cardiovascular disease (CVD), including stroke [1]. After the introduction of biological DMARDs in 1999 and the treat to target strategy, more patients reach low disease activity and remission, which is associated with lower CVD risk [2]. Few previous studies have examined stroke occurrence in RA patients before and after these improvements in RA management.ObjectivesTo investigate stroke events in RA patients diagnosed before and after 1999 compared with the total population.MethodsWe included 771 RA patients diagnosed during 1972-1998 and 1050 during 1999-2013 at the main rheumatological department of Hordaland county, Norway. The total population of the same county and time period were used as a comparison cohort. Data on stroke events were obtained from regional cardiovascular registries or hospital patient administrative systems during 1972-2014. Aggregated counts of stroke events and population counts from the comparison cohort were used to estimate expected counts of stroke hospitalisation in the RA cohort per 5-year age group, sex and calendar year. We then estimated standardised event ratios (SERs) by Poisson regression as a measure of excess stroke events in RA patients compared with the total population.ResultsIn total, 152 stroke events occurred in 112 RA patients diagnosed during 1972-1998 over 15137 person-years of follow-up and 86 stroke events in 70 RA patients diagnosed during 1999-2013 over 8672 person-years of follow-up. RA patients diagnosed in the later period were on average 2.1 years older (56 years) at RA diagnosis, but the proportion of women was similar in both groups.Both RA patients diagnosed before and after 1998 had an excess of stroke events compared with the total population (SER 1.20, 95% CI 1.00-1.44 and SER 1.22, 95% CI 1.05-1.42 respectively). RA patients younger than 60 years of age did not appear to have significant excess stroke events in either group.ConclusionThese results indicate a similar excess of stroke events in RA patients diagnosed before and after 1999. This warrants continued awareness regarding stroke prevention in RA patients, even after the recent improvements in RA treatment.