Background A wealth of studies have linked rheumatoid arthritis (RA) with an excess mortality compared to the general population. With increasingly effective anti-rheumatic treatment strategies there is, however, considerable uncertainty whether this mortality gap still exists and, if so, how soon after RA onset it occurs.
Objectives To assess the mortality in RA compared to the general population with specific focus on when during the course of the disease the risk is increased and if it also applies to patients diagnosed in recent years.
Methods We performed a population-based cohort study of 17,512 patients with new-onset RA (identified from the Swedish Rheumatology Quality Register) 1997 through 2015, and 78,847 individually matched general population comparator subjects. We followed all individuals using nationwide census registers with full coverage to identify all deaths through 2015. We calculated mortality rates with 95% confidence intervals (CI) and compared the mortality in RA to that in the general population using Cox proportional hazards models adjusted for age, sex, year of diagnosis, and residential area.
Results During a mean follow-up from RA diagnosis of 7 years, 2,386 RA patients and 9,850 population comparator subjects died (crude incidence: 19 per 1000 in RA and 18 per 1000 in the general population), with only a marginal decline (in the RA and in the general population cohort) during the study period. The overall HR was 0.99 (0.95–1.04), but whereas there was no increase in mortality during the first five years after RA diagnosis; the HR ≥10 years after RA onset was 40% increased. The overall pattern of HRs was similar for patients diagnosed 1997–2001, 2002–2006, and 2007–2011 (table).
Conclusions The five-year mortality in RA is not increased, neither for patients diagnosed in the past nor for those diagnosed during the most recent five years. By contrast, at least in the most recent inception cohort for which ten-year mortality currently can be calculated (those diagnosed up to 2006), RA is still associated with an increased risk of death.
Disclosure of Interest None declared