Ischemic stroke risk factors not included in the CHADS-VASC score in patients with non-valvular atrial fibrillation

Fatores de risco de AVC isquêmico não incluídos no escore CHADS-VASC em pacientes com fibrilação atrial não valvar

Abstract

Background

In patients with atrial fibrillation, the CHA₂DS₂-VAS_C score guides stroke prevention using anticoagulants, but it is an imperfect score. Other potential risk factors such as renal failure, the type of atrial fibrillation, active smoking, cancer, sleep apnea or systemic inflammation have less well been investigated.

Objective

To assess the impact of these factors on ischemic stroke risk in patients with non-valvular atrial fibrillation.

Methods

On a population of 248 patients (124 patients with acute ischemic stroke and 124 controls), we performed a logistic regression to assess the impact of multiple non-classic risk factors for the prediction of acute ischemic stroke. Their impact on mortality was assessed by performing a survival analysis.

Results

A high CHA₂DS₂-VASc score (OR 1.75; 95% CI 1.13–2.70; p = 0.032), treatment with anticoagulants (OR 0.19; 95% CI 0.07–0.51; p < 0.001) and permanent atrial fibrillation (OR 6.31; 95% CI 2.46–16.19; p < 0.001) were independently associated with acute ischemic stroke. Renal failure and chronic obstructive pulmonary disease predicted a higher mortality. After adjusting for age, sex, the CHA₂DS₂-VASc score and the use of anticoagulants, the only risk factor predictive for acute ischemic stroke was the permanent type of AF (OR: 8.0 [95% CI 2.5–25.5], p < 0.001).

Conclusions

The CHA₂DS₂-VASc score, the absence of anticoagulants and the permanent type of atrial fibrillation were the main predictive factors for the occurrence of acute ischemic stroke. Larger studies are necessary for conclusive results about other factors.

Keywords
Atrial Fibrillation; Stroke; Risk Factors; CHA₂DS₂-VASc