Background/Purpose: Studies evaluating trends in rheumatoid arthritis (RA) mortality over time have produced inconsistent results. Our aim was to estimate all-cause mortality in RA between 1996-2009, assess changes in mortality over time, and to compare mortality rates in RA with the general population.

Methods: We studied all residents in Ontario, Canada’s most populous province (N~13 million). Patients with RA were identified using the Ontario RA administrative Database (ORAD), a population-based research cohort generated from administrative data using a validated RA case definition. Linking to vital statistics data, we estimated annual all-cause mortality in RA by dividing the number of deaths among RA patients by the number of RA patients in each year. To compare mortality rates over time, we standardized for age and sex using the 2001 Ontario census population estimates. Age specific and age-and-sex standardized all-cause mortality estimates are expressed as the number of deaths per 1,000 RA patients for each year of the study period. The age-and-sex-standardized all-cause mortality estimates were compared in terms of relative percentage change between 1996 and 2008. We compared changes in mortality over time in RA patients, to estimates of mortality in the general population, over the same period. Finally, standardized mortality ratios (SMRs) were calculated, which provides the ratio of the mortality rate in RA patients versus the age and sex matched general population mortality.

Results: Age-and-sex standardized all-cause mortality ranged from 13.0 deaths per 1,000 RA patients (95%CI 12.2,13.9) in 1996 to 9.2 deaths per 1,000 RA patients (95%CI 8.4,10.0) in 2010. In 2008, the age-standardized rate for RA females was 8.8 deaths per 1,000 (95%CI 8.0,9.6) compared to 12.1 deaths per 1,000 (95%CI 10.3,14.2) in males, and rates were higher among males than females in all age groups. Age-specific all-cause mortality in RA patients increased with increasing age. Comparing RA mortality trends to the general population (Figure), since 1996, all-cause mortality decreased for RA by a relative 21.4%, with a smaller decrease (13.4%) in the general population. The SMRs for RA patients in 2000, 2004, and 2008 were 1.50 (95% CI 1.43-1.57), 1.43 (95%CI 1.37-1.50), and 1.41 (95%CI 1.35,1.47) respectively.

Conclusion: All-cause mortality for patients with RA has decreased over the past decade but remains elevated compared to the general population. Our results suggest 40-50% more deaths among RA patients compared to the general population. SMR estimates over the past decade do suggest the mortality gap may be slowly narrowing.