Causes of death in rheumatoid arthritis: How do they compare to the general population?

Objective. To compare mortality rates, underlying causes of death, excess mortality, and years of potential life lost (YPLL) among patients with rheumatoid arthritis (RA) relative to the general population. Methods. We studied an inception cohort of 87,114 Ontario-based RA patients and 348,456 age/sex/area-matched general population comparators from years 2000 to 2013. All-cause, cause-specific, and excess mortality rates, mortality rate ratios (MRRs), and the YPLL were estimated. Results. A total of 11,778 RA patients (14%) and 32,472 comparators (9%) died during 508,385 and 1,769,365 patient-years of follow-up, respectively, for corresponding mortality rates of 232 (95% confidence interval [95% CI] 228-236) and 184 (95% CI 182-186) per 10,000 patient-years. The leading causes of death in both groups were diseases of the circulatory system, cancer, and respiratory conditions. Increased mortality for all-cause and specific causes was observed in RA patients relative to the general population. MRRs were elevated for most causes of death. Age-specific mortality ratios illustrated a high excess mortality among RA patients YPLL for RA patients was 7,436 per 10,000 persons, compared with 4,083 YPLL among those without RA. Conclusion. Among most causes of death, mortality rates were increased in RA patients relative to the general population. The potential life years lost (before the age of 75 years) among RA patients was roughly double that among those without RA, reflecting higher rate ratios for most causes of death and RA patients dying at earlier ages.