Trends in the occurrence of ischaemic heart disease over time in rheumatoid arthritis: 1821 patients from 1972 to 2017

Objective To evaluate trends of acute myocardial infarction (AMI) and ischaemic heart disease (IHD) in rheumatoid arthritis (RA) patients compared with the general population over time. Method We performed a retrospective cohort study of 1821 RA patients diagnosed from 1972 to 2013. Aggregated counts of the total population of the same county (Hordaland, Norway) and period were used for comparison. Information on AMI and IHD events was obtained from hospital patient administrative systems or cardiovascular registries. We estimated incidence rates and excess of events [standardized event ratio (SER) with 95% confidence interval (CI)] compared with the general population by Poisson regression. Results There was an average annual decline of 1.6% in age- and gender-adjusted AMI incidence rates from 1972 to 2017 (p < 0.035). The difference in events (excess events) in RA patients compared with the general population declined on average by 1.3% per year for AMI and by 2.3% for IHD from 1972 to 2014. There were no significant excess AMI (SER 1.05, 95% CI 0.82-1.35) or IHD events (SER 1.02, 95% CI 0.89-1.16) for RA patients diagnosed after 1998 compared with the general population. Conclusion Incidence rates and excess events of AMI and IHD in RA patients declined from 1972 to 2017. There were no excess AMI or IHD events in RA patients diagnosed after 1998 compared with the general population.