Abstract T P149: Prevalence of Atrial Fibrillation in Stroke Patients: an Observational Study in the Very Old
Background: Atrial fibrillation (AF) is the most common arrhythmia in older adults, increases with age and it is a well-established risk factor for stroke. Recent studies showed that up to 15% of stroke admissions present with AF. Furthermore, the number of patients with AF is expected to increase 2.5-fold in the next 50 years. Therefore, stroke prevention must constitute a priority in current health policies. Nonetheless, little is known about the prevalence of paroxysmal AF (PAF) in older adults. We aim to assess the prevalence of AF in stroke patients and to identify further paroxysmal events in patients with reported normal rhythm on admission.
Methods: Observational study of routinely collected data over a 26-month period in a Stroke Unit within an Internal Medicine Department. All types of stroke were analyzed. AF diagnosis based on medical records, admission 12-lead electrocardiogram (ECG) or 24-hour Holter monitoring. Descriptive statistics were used.
Results: A total of 332 consecutive patients were identified. Median age (IQR) was 77 (68-83) years; 53.0% women; 2.4% hemorrhagic stroke; 59.5% aged 75 years or older. Overall prevalence of AF on admission was 23.2%, of which 10.4% were newly diagnosed. 34.8% of the patients with known AF were on anticoagulation. Amongst the patients with reported normal rhythm on admission, a 1.9% of PAF was demonstrated on 24-hour Holter monitoring recorded during acute phase. In the 75 years or older cohort, we found higher prevalence of AF (31.3% vs 11.2%, p<.001) but no difference of that of PAF (2.2% vs 1.7%, p=NS). Cardioembolism was much more prevalent in the very old (33.0% vs 17.9%, p=.03).
Conclusion: We report a higher prevalence of AF in patients presenting with stroke than published literature. Some patients were unaware of this condition. Surprisingly, only a third of patients with known AF were on anticoagulation. We were able to detect a high prevalence of PAF on 24-hour Holter monitoring during acute phase. However, PAF is as prevalent in the very old as it is in younger patients. Cardioembolic stroke is more frequent in the very old; therefore exhaustive investigation to detect AF in this cohort should be sought, so an effective secondary prophylaxis can be offered.
Author Disclosures: L. Mieiro: None. A. Miranda: None. M. Alves: None. M. Narciso: None. F. Lopes: None. T. Fonseca: None.
- © 2014 by American Heart Association, Inc.