Risks of Myocardial Infarction and Mortality in Patients with Incident Rheumatoid Arthritis Compared with a Matched General Population: A Danish Nationwide Cohort Study.

Background and Aims: Rheumatoid arthritis (RA) is increasingly being recognized as cardiovascular risk factor. We examined temporal trends in the risks of myocardial infarction (MI) and all-cause mortality in patients with newly diagnosed RA without a history of cardiovascular disease (CVD) compared with a matched general population. Methods and Results: Patients with a first diagnosis of RA without prior CVD (N=20,937) were identified through national health registries between 1996 and 2017. On the index date, each patient was matched by age and sex to five individuals from the general population with neither RA nor CVD (N=104,685) and followed for 5 years. Among patients with RA, the 5-year cumulative incidence proportions for MI declined from 2.6% in 1996-2000 to 1.5% in 2011-2017 (hazard ratio (HR) 0.59; 95% CI 0.45-0.78), whereas all-cause mortality decreased from 9.3% to 7.7% (HR 0.83; 95% CI 0.72-0.95). The reduced risk of MI in patients with RA mirrored the decline observed in a matched general population while the mortality gap between RA and general population individuals was reduced between 1996 and 2010. Statin prescription fillings at 1-year follow-up, a proxy for prophylactic medical intervention, was highest in 2011-2017, reaching 19% among RA patients as well as general population individuals. Conclusion: Despite a gradual decline in the risk of MI and all-cause mortality from 1996 to 2017, patients with RA remain at higher risk of both MI and death than their matched general population individuals. This increased risk was not reflected by improved primary prophylactic medical interventions.