Smartphone-Based Atrial Fibrillation Screening in Community Pharmacy Settings Diagnostic Yield, Risk Stratification, and Anticoagulation Initiation Across Sixteen Pharmacy Sites

Abstract

Many cases of atrial fibrillation (AF) are paroxysmal or asymptomatic and remain undetected until a thromboembolic stroke. Smartphone-based detection through photoplethysmography (PPG) and single-lead ECG offers a low-cost screening modality, and community pharmacies provide an accessible setting with high routine footfall. We screened 425 adults aged 55 years and older across sixteen urban and semi-urban community pharmacies over a six-month period. AF was newly detected in 31 individuals (7.3%), with detection rates rising from 0.8% in those under 55 to 12.4% in those aged 75 and over. The single-lead ECG device achieved an area under the ROC curve of 0.94 against cardiologist 12-lead ECG, while smartphone PPG achieved 0.89. Of newly detected AF cases, 29 (93.5%) had a CHA₂DS₂-VASc score of 2 or higher and met criteria for oral anticoagulation; 24 (77.4%) initiated anticoagulation within 30 days of screening. The yield, accuracy, and downstream anticoagulation uptake support pharmacy-based smartphone AF screening as a scalable strategy for early detection in older adults.

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