Jessica Widdifield1, Sasha Bernatsky2, J Michael Paterson3, George Tomlinson4, Karen Tu5, Bindee Kuriya6, J Carter Thorne7, Janet E Pope8, Simon Hollands9, Claire Bombardier4. 1. Institute for Clinical Evaluative Sciences, Toronto, Ontario, and McGill University, Montreal, Quebec, Canada. 2. McGill University, Montreal, Quebec, Canada. 3. Institute for Clinical Evaluative Sciences and University of Toronto, Toronto, Ontario, and McMaster University, Hamilton, Ontario, Canada. 4. University of Toronto, Toronto, Ontario, Canada. 5. Institute for Clinical Evaluative Sciences and University of Toronto, Toronto, Ontario, Canada. 6. Mount Sinai Hospital, Toronto, Ontario, Canada. 7. Southlake Regional Health Centre, Newmarket, Ontario, Canada. 8. Western University, London, Ontario, Canada. 9. Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada.
Abstract
OBJECTIVE: To evaluate excess mortality over time, comparing rheumatoid arthritis (RA) patients with the general population. METHODS: We computed all-cause mortality rates among Ontario residents age ≥15 years with RA versus without RA from 1996 to 2009. Age- and sex-standardized mortality rates were expressed as the number of deaths per 1,000 population. Excess mortality rates were calculated as the difference between death rates among RA patients and those in the general population. We estimated standardized mortality ratios (SMRs) and mortality rate ratios (MRRs) to assess relative excess mortality over time. RESULTS: From 1996 to 2009, SMRs in RA ranged from 13.0 (95% confidence interval [95% CI] 12.2, 13.9) to 9.2 deaths per 1,000 RA patients (95% CI 8.4, 10.0); and for those without RA from 8.7 (95% CI 8.6, 8.7) to 6.0 deaths (95% CI 5.9, 6.0) per 1,000 general population. Over the study period, the excess mortality rate among RA patients was approximately 3 excess deaths per 1,000 population. Relative reductions in standardized mortality rates occurred over time for those with and without RA (-21.4% versus -13.4%). The SMRs for RA patients in 1996-1997, 2000-2001, 2004-2005, and 2008-2009 were 1.51 (95% CI 1.43, 1.59), 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. We did not find a significant change in the MRR by calendar time. CONCLUSION: Mortality for RA patients has decreased over time but remains elevated compared to the general population, with 40-50% more deaths among RA patients. The relative excess mortality over time (mortality gap) remains unchanged in our sample.
OBJECTIVE: To evaluate excess mortality over time, comparing rheumatoid arthritis (RA) patients with the general population. METHODS: We computed all-cause mortality rates among Ontario residents age ≥15 years with RA versus without RA from 1996 to 2009. Age- and sex-standardized mortality rates were expressed as the number of deaths per 1,000 population. Excess mortality rates were calculated as the difference between death rates among RApatients and those in the general population. We estimated standardized mortality ratios (SMRs) and mortality rate ratios (MRRs) to assess relative excess mortality over time. RESULTS: From 1996 to 2009, SMRs in RA ranged from 13.0 (95% confidence interval [95% CI] 12.2, 13.9) to 9.2 deaths per 1,000 RApatients (95% CI 8.4, 10.0); and for those without RA from 8.7 (95% CI 8.6, 8.7) to 6.0 deaths (95% CI 5.9, 6.0) per 1,000 general population. Over the study period, the excess mortality rate among RApatients was approximately 3 excess deaths per 1,000 population. Relative reductions in standardized mortality rates occurred over time for those with and without RA (-21.4% versus -13.4%). The SMRs for RApatients in 1996-1997, 2000-2001, 2004-2005, and 2008-2009 were 1.51 (95% CI 1.43, 1.59), 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. We did not find a significant change in the MRR by calendar time. CONCLUSION: Mortality for RApatients has decreased over time but remains elevated compared to the general population, with 40-50% more deaths among RApatients. The relative excess mortality over time (mortality gap) remains unchanged in our sample.