Cardiac symptom burden and arrhythmia recurrence drives digital health use: results from the iHEART randomized controlled trial

Aims Digital health can transform the management of atrial fibrillation (AF) and enable patients to take a central role in detecting symptoms and self-managing AF. There is a gap in understanding factors that support sustained use of digital health tools for patients with AF. This study identified predictors of Alivecor(R) KardiaMobile ECG monitor usage among patients with AF enrolled in the iPhone(R)Helping Evaluate Atrial fibrillation Rhythm through Technology (iHEART) randomized controlled trial. Methods and results We analysed data from 105 English and Spanish-speaking adults with AF enrolled in the intervention arm of the iHEART trial. The iHEART intervention included smartphone-based electrocardiogram self-monitoring with Alivecor(R) KardiaMobile and triweekly text messages for 6 months. The primary outcome was use of Alivecor(R) categorized as: infrequent (<= 5 times/week), moderate (>5 times and <= 11 times/week), and frequent (>11 times/week). We applied multinomial logistic regression modelling to characterize frequency and predictors of use. Of the 105 participants, 25% were female, 75% were White, and 45% were >= 65 years of age. Premature atrial contractions (PACs) [adjusted odds ratio (OR): 1.23, 1.08-1.40, P = 0.002] predicted frequent as compared to infrequent use. PACs (adjusted OR: 1.17, 95% confidence interval 1.06-1.30, P = 0.003), lower symptom burden (adjusted OR: 1.06, 1.01-1.11, P = 0.02), and less treatment concern (adjusted OR: 0.96, 0.93-0.99, P = 0.02) predicted moderate as compared to infrequent use. Conclusions Frequent use of AliveCor(R) is associated with AF symptoms and potentially symptomatic cardiac events. Symptom burden and frequency should be measured and incorporated into analyses of future digital health trials for AF management.