Background Rheumatoid arthritis (RA) patients have an increased risk of mortality, which has been partially attributed to higher cardiovascular mortality.
Objectives To determine the mortality and their risk factors over 2 years of follow up in a cohort study.
Methods A total of 406 RA patients and 209 age and sex-matched normal controls enrolled in the KNUH Atherosclerosis Risk in RA (KARRA) cohort was assessed according to a standardized protocol for two years. Demographic data, traditional CV risk factors, and clinical and laboratory variables relevant to disease activity were obtained. Erythrocyte sedimentation rate-area under the curve (ESR-AUC) overtime was calculated to assess the inflammatory burden. The carotid intima-media thickness (IMT) and plaques were measured using carotid artery ultrasound.
Results Among RA patients, a total 10 deaths (1.25% per year) occurred during 2 years follow-up period while there were no deaths among the controls. Disease duration of RA until deaths was 32.3±34.0 years. Causes of death included infection (4 pneumonia and 2 septic shock), sudden cardiac death (1 patient), congestive heart failure (1 patient), and others (2 patients). Risk factors for mortality included age (alive vs. dead patients: 55±12.1 vs. 71±9.5, p<0.001), functional class of RA (1.9±0.5 vs. 2.4±0.5, p<0.001), modified Korean health assessment questionnaire (mKHAQ) (9.6±7.8 vs. 22.1±13.7, p<0.05), DAS28 (3.3±4.5 vs. 4.6±1.3, p<0.006), ESR (23.3±20.1 vs 64.3±38.2, p<0.01), ESR-AUC (2,005±1,874 vs 4,106±1,649, p<0.01), and carotid artery plaque number (0.7±1.3 vs 2.5±2.1, p<0.05). After multivariate analysis, mKHAQ and ESR were found to be significantly associated with mortality (p<0.01 and p<0.05, respectively). mKHAQ and ESR cut-off points were made using a receiver-operating characteristic (ROC)-curve. Among the patients with mKHAQ <19, no death occurred in patients with normal ESR, while 3 deaths in patients with abnormal ESR (Figure). Mortality was highest among patients with HAQ ≥19 and abnormal ESR (6 deaths among 41 patients, 14.6%).
Conclusions These results suggest that functional outcome and inflammatory activity of RA have a critical prognostic impact and tight control of inflammation may improve survival in this population.
Disclosure of Interest None declared