Gregory M Marcus

Background The prognosis for atrial fibrillation (AF) patients is based on data that is decades old. Given evolving standards of clinical practice, we sought to evaluate temporal trends in clinically important outcomes among patients with AF. Methods California's Department of Health Care Access and Information databases were used to identify adults aged ≥ 18 years with AF receiving hospital-based care in California. We compared 3 time-periods: 2005–2009, 2010–2014, and 2015–2019. ICD codes were used to identify chronic diseases and acute events. The outcomes were incident ischemic stroke, intracranial hemorrhage, and overall mortality. Results We included 2 009 832 patients with AF (52.7% males, 70.7% Whites, and mean age of 75.0 years), divided in 3 cohorts: 2005–2009 (n = 738 954), 2010–2014 (n = 609 447), and 2015–2019 (n = 661 431). Each outcome became substantially less common with time: compared to 2005–2009, AF patients diagnosed in 2015–2019 experienced a 34% (adjusted hazard ratio [HR] 0.66, 95% CI 0.64–0.69), 22% (HR 0.78, 0.75–0.82), and 24% (HR 0.76, 0.75–0.77) reduction in risk of incident ischemic stroke, intracranial hemorrhage, and mortality, respectively. Between 2005–2009 and 2015–2019, patients aged ≥ 65 years experienced more reductions in each outcome compared to younger patients (p < 0.001 for all), and declines in each outcome were significantly lower for Hispanics and Blacks compared to white patients. Conclusion The risks of stroke, intracranial hemorrhage, and death have significantly declined among AF patients, although differences in the magnitude of improvement of these outcomes by demographic groups were observed. Commonly described estimates of the prognosis for AF patients should be updated to reflect contemporary care.