The ABC-Stroke Risk Score and Effects of Atrial Fibrillation Screening on Stroke Prevention: Results From the...

Area of Science:

• Cardiology
• Preventive Medicine
• Clinical Risk Stratification

Background:

• The ABC-stroke score is a validated tool for predicting stroke or systemic embolism (SE) in patients with atrial fibrillation (AF).
• Its utility in AF-naïve individuals and for guiding AF screening remains to be fully elucidated.

Purpose of the Study:

• To evaluate the ABC-stroke score's effectiveness in predicting stroke in AF-naïve individuals.
• To assess its utility in risk stratifying for AF screening in this population.

Main Methods:

• Secondary analysis of the LOOP study (NCT02036450), which randomized 6004 AF-naïve individuals (aged 70-90) with stroke risk factors.
• Participants were assigned to either continuous ECG monitoring with an implantable loop recorder or usual care.
• ABC-stroke score at baseline was used to stratify participants into risk groups (≤1%/year vs. >1%/year).

Main Results:

• A higher ABC-stroke score (>1% annual risk) was associated with increased risk of stroke/SE, stroke/SE/cardiovascular death, and all-cause death.
• No significant reduction in these outcomes was observed with implantable loop recorder screening versus usual care across any ABC-stroke risk strata.
• No significant interaction was found between screening strategy and ABC-stroke risk score.

Conclusions:

• In elderly, AF-naïve individuals with stroke risk factors, the ABC-stroke score can identify those at higher risk of stroke.
• The score's ability to pinpoint individuals who would benefit most from AF screening and subsequent preventive treatment is limited.
• These findings are hypothesis-generating and suggest a need for further research.