Temporal trends in mortality, heart failure hospitalization, and stroke in heart failure patients with and without atrial fibrillation: A nationwide study from 1997-2018 on 152,059 patients

Background Given the many advances in treating heart failure (HF) and atrial fibrillation (AF) separately over the past decades, it remains unclear how the prognosis of patients diagnosed with both conditions has changed over time. We aimed to investigate the temporal trends in clinical outcomes from 1997 to 2018 in patients diagnosed with both HF and AF. Methods From Danish nationwide registries, we identified 152,059 patients with a first-time HF-diagnosis from 1997 to 2018. Patients were grouped according to year of new-onset HF and AF-status: Prevalent AF (n=34,734), New-onset HF (n=12,691), and No AF (n=104,634). Outcomes of interest were the five-year risk of all-cause mortality, HF-hospitalization, and stroke. Results Between 1997 and 2018, the proportion of patients with prevalent or new-onset AF increased from 24.7% (n=9256) to 35.8% (n=14,970). The five-year risk of all-cause mortality decreased from 69.1% (95% CI): 67.9%-70.2%) to 51.3% (49.9%-52.7%), 62.3% (60.5%-64.4%) to 43.0% (40.5%-45.5%), and 61.9% (61.3%-62.4%) to 36.7% (35.9%-37.6%) for the prevalent AF, new-onset AF, and no AF group, respectively. Minimal changes were observed in the risk of HF-hospitalization. The five-year risk of stroke decreased from 8.5% (7.8%-9.1%) to 5.0% (4.4%-5.5%) in the prevalent AF group, 8.2% (7.2%-9.2%) to 4.6% (3.7%-5.5%) in the new-onset AF group, and 6.3% (6.1%-6.6%) to 4.9% (4.6%-5.3%) in the no AF group. Simultaneously, patients prescribed anticoagulant therapy within 90 days after HF-onset increased from 42.7% to 93.1% in patients with prevalent AF and 41.9% to 92.5% in patients with new-onset AF. Conclusion From 1997 to 2018, we observed an increase in patients with HF and coexisting AF. Mortality and stroke risk decreased across all patient groups regardless of AF-status. Anticoagulation therapy increased, and stroke risk in patients with HF and AF was reduced to similar levels as HF patients without AF at the end of the study period. Clinical Perspective What is new? In patients with heart failure, an increasing proportion had concomitant atrial fibrillation in 2018 versus 1997. The mortality- and stroke risk decreased for all patients with heart failure over the past two decades, also for patients with coexisting atrial fibrillation, and more patients received guideline-recommended therapy in 2018 versus in 1997. What are the clinical implications? The increasing trend of patients with heart failure and coexisting atrial fibrillation necessitates a better understanding of the coexistence of these two conditions, of which this study provides insight into the evolving prognosis and management landscape of individuals with both heart failure and atrial fibrillation over the past two decades.