Prognostic value of atrial fibrillation at different stages of long­term outpatient follow­up in patients after cerebrovascular accident (based on the REGION­M registry)

Aim. To study the prognostic value of atrial fibrillation (AF) during longterm follow-up of patients with cerebrovascular accident (CVA).

Material and methods. The study was conducted as part of the prospective part of the retrospective-prospective registry REGION-M registry. A total of 684 patients discharged from the hospital with a confirmed CVA between 2012 and 2017 and assigned to an outpatient clinic were included. The median follow-up was 5,0 [2,0; 6,8] years. AF was determined based on the diagnosis during the patient's hospital stay and/or at the first outpatient visit after discharge. The primary endpoint was all-cause death. An analysis of AF prognostic role was conducted for the entire follow-up period from hospital discharge to 2022.

Results. Patients with AF accounted for 29,2% (n=200). Comparison of the groups of patients with and without AF showed that patients with AF were older and had a higher number of comorbidities. AF had a paradoxical positive effect on the death risk (hazard ratio (HR) 0,998 (95% confidence interval (CI): 0,996-1,000), p=0,017). In this regard, we suggested that the AF effect on cumulative survival was disproportionate, i.e. changed over time. Therefore, the contribution of AF to death risk was assessed separately for three follow-up periods as follows: early outpatient follow-up — from discharge to contact in 20172018; intermediate — from the moment of the previous follow-up (2017 or 2018) to May 2020; long-tern — from 2020 to 2022. Differences in death risk between patients with and without AF were significant only in early (HR 1,003 (95% CI: 1,000-1,005) (p=0,016)) and intermediate (HR 1,004 (95% CI: 1,001-1,007) periods (p=0,016)). No significant differences in death risk between patients with and without AF were observed in the long-term follow-up period. Therefore, AF was not included in the multivariate regression analysis.

Conclusion. AF negatively impacts the death risk during the first 3-4 years after CVA. After this period, AF loses its independent prognostic significance.

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