Life-Years Lost After Newly Diagnosed Atrial Fibrillation in Patients with Heart Failure

Objective: Prior work estimated excess death rates associated with atrial fibrillation (AF) in heart failure (HF) with hazard ratios (HR). The aim was to estimate the life-years lost after newly diagnosed AF in HF patients. Methods: Among patients diagnosed with HF in 2008-2018 in the nationwide Danish Heart Failure Registry, we compared patients with incident AF to referents matched on age, sex, and time since HF. We estimated the marginal hazard ratio (HR) for death and marginal difference in restricted mean survival times (RMST) between AF cases and referents at 10 years after AF diagnosis. We adjusted for sex, age at AF diagnosis, clinical and lifestyle risk factors, and medications. Results: Among 4463 AF cases and 17,792 referents (mean age 73.7 years, 29% women), the HR was 1.41 (95% CI 1.38; 1.44) but there was evidence of non-proportional hazards. The difference in RMST was -18.2 months (95% CI -16.8; -19.6) at 10 years after AF diagnosis. There were differences in life-years lost between patients diagnosed with AF >1 year and <= 1 year after HF (-25.7 months, 95% CI -23.7; -27.7 vs -10.4 months, 95% CI -8.2; -12.5, p < 0.001), women and men (-20.3 months, 95% CI -17.7; -21.9 vs -17.2 months, 95% CI -15.5; -19.0, p = 0.05), patients with low, medium, and high CHA(2)DS(2)-VASc (10.3 months, 95% CI -4.6; -16.1 vs -18.5 months, 95% CI -16.7; -20.4 vs 22.1, 95% CI -18.8; -22.3, p = 0.002). Conclusion: HF patients with incident AF lost on average 1.5 life-years over 10 years after AF. Life-years lost were larger among patients diagnosed with AF >1 year after HF, women, and patients with higher CHA(2)DS(2)-VASc.