Temporal Trends and Short‐ and Long‐Term Mortality of People With Acute Myocardial Infarction and Rheumatoid Arthritis: A Nationwide Cohort Study

OBJECTIVE: We investigated whether a diagnosis of rheumatoid arthritis (RA) affects the quality of inpatient acute myocardial infarction (AMI) care and long-term mortality post-AMI. METHODS: We analyzed data from 784,091 adults, 6,047 with a diagnosis of RA, from England and Wales hospitalized with AMI between 2005 and 2019 from the Myocardial Ischaemia National Audit Project registry, linked with Office for National Statistics mortality data and hospital episode statistics. Cox regression models were used to compare risk of all-cause mortality at different time points according to the presence of RA. RESULTS: There was no difference in adjusted 30-day mortality between groups (adjusted hazard ratio [aHR] 1.09, 95% confidence interval [CI] 0.99-1.19; P = 0.075). Beyond this, at 1 year (aHR 1.14, 95% CI 1.07-1.21), 5 years, (aHR 1.28, 95% CI 1.23-1.33), and to the end of the study period (aHR 1.31, 95% CI 1.26-1.36), the risk of all-cause mortality was significantly higher in patients with RA (all P < 0.001). Risk of cardiovascular mortality was not significantly different at 30 days or 1 year (aHR 1.08, 95% CI 1.00-1.17; P = 0.058), but it was at 5 years (aHR 1.15, 95% CI 1.08-1.23; P < 0.001) and to the study endpoint post-AMI (aHR 1.18, 95% CI 1.11-1.24; P < 0.001). CONCLUSION: We found no meaningful disparities in inpatient care according to the presence of RA; however, those with RA have elevated long-term all-cause mortality post-AMI. Our findings suggest that the mortality burden of RA post-AMI is not driven by the quality of AMI care during admission and is likely driven by the progressive nature of the comorbidities and the complications of treatments associated with RA.