SAT0044 The Role of C-Reactive Protein or Erythrocyte Sedimentation Rate in Predicting Cardiovascular Outcomes in Rheumatoid Arthritis: Analysis of Data from US Managed Care Organization
Authors: J. An, E. Alemao, T. Cheetham, K. Reynolds, H. Kawabata, D. Solomon
Journal: Annals of the Rheumatic Diseases (2014)

<h3>Background</h3> Patients with RA are at a 2- to 3-fold higher risk for cardiovascular (CV) events. Disease activity in RA is often assessed by C-reactive protein (CRP) or erythrocyte sedimentation rate (ESR), and there is growing evidence that the disease activity in RA is associated with increased CV risks. <h3>Objectives</h3> To test whether CRP or ESR improves CV risk prediction in RA patients. <h3>Methods</h3> Patients aged ≥18 years and with ≥2 RA diagnoses with a DMARD were identified between 01/01/2007 and 12/31/2011 within Kaiser Permanente Southern California. Individuals were followed from the first RA diagnosis or prescription date (index) until death, disenrollment, study end period (12/31/2011) or first CV outcome (myocardial infarction, angina, stroke, transient ischaemic attack, intermittent claudication, heart failure or coronary heart disease death). The base-case prediction model included traditional predictors of CV events similar to the Framingham Heart Study model (FHS).<sup>1</sup> Patients with a previous history of CV events or patients with any missing values were excluded from the analysis. Event-free survival distributions by baseline CRP tertiles (≤7.4, 7.4–17.8, ≥17.8 mg/L) or ESR tertiles (male: ≤13, 13–36, ≥36 mm/h; female: ≤20, 20–40, ≥40 mm/h) were compared using a Kaplan–Meier log rank test. Multivariable Cox proportional hazards regression models were used to test the relation between risk predictors and CV outcomes. Harrell9s C-index and net reclassification improvement (NRI) were used to evaluate the discriminatory ability of the prediction model, including CRP/ESR compared to the FHS prediction model. <h3>Results</h3> A total of 7277 RA patients were included in the cohort with median follow-up of 3.8 years. The mean (SD) age was 55.7 (13.9) years, with 79% being female. At baseline, 54% had hypertension or were taking antihypertensive medications, 51% had dyslipidaemia, 14% had diabetes and 12% were current smokers. Only 39% of the study population had baseline CRP values, with a mean (SD) of 20.8 (28.5) mg/L, whereas 99% had baseline ESR values, with a mean (SD) of 31.3 (28.0) mm/h for males and 35.0 (25.3) mm/h for females. CV event-free survival was significantly lower in patients with a high CRP or ESR range (log rank test: p&lt;0.001). Using a base-case FHS prediction model, all of the factors except for dyslipidaemia were significant and positively correlated with the risk of CV outcomes (C-index: 0.7762). Including CRP/ESR as an additional factor, the new model slightly improved the model discrimination (C-index: 0.7784, NRI: 1.112%). As well, there was a trend towards a higher CRP/ESR being correlated with an increased risk of CV outcomes (hazard ratio [HR] of high vs low CRP/ESR=1.25; 95% CI 0.98, 1.61, HR of medium vs low CRP/ESR=1.28; 95% CI 0.99, 1.65). <h3>Conclusions</h3> Baseline CRP or ESR were marginally associated with an increased risk of CV outcomes and the inclusion of CRP/ESR in the FHS model resulted in a small improvement in the reclassification of CV risk. <h3>References</h3> Wilson PWF. Circ Cardiovasc Qual Outcomes 2008 November <h3>Disclosure of Interest</h3> J. An Grant/research support: BMS, Merck, Genentech, E. Alemao Shareholder of: BMS, Employee of: BMS, T. Cheetham Grant/research support: BMS, Gilead, K. Reynolds: None declared, H. Kawabata: None declared, D. Solomon: None declared <h3>DOI</h3> 10.1136/annrheumdis-2014-eular.1742