Use of Web-Based Patient Portals in Patients With Atrial Fibrillation Is Associated With Higher Readmissions.

Background: The impact of web-based patient portals on patient outcomes-specifically hospital readmissions in patients with atrial fibrillation (AF)-remains understudied. Methods: This single-center retrospective cohort study investigated the use of an online portal system (MyChart) by patients hospitalized from January 1, 2014 to June 30, 2017 for AF. During the study period, 11,334 unique AF admissions were identified; 50.3% were MyChart users and 49.7% were non-MyChart users. Patients who experienced inpatient mortality were excluded. The study groups were analyzed for demographic variables, comorbidities, readmission rates, and the frequency of MyChart use during the 3.5-year time frame. Results: MyChart users were younger (median age, 74 years, interquartile range [IQR] 66-82 vs 77 years, IQR 68-85; P<0.0001) and more likely to be white (91.9% vs 84.6%; P<0.0001), but the sex distribution was similar between groups, with 51.8% males in the MyChart group vs 53.2% in the non-MyChart group. MyChart users had a significantly higher rate of readmission compared to non-MyChart users at 1 year (43.0% vs 32.0%, respectively; P<0.0001). MyChart users who were readmitted had a higher median number of logins to MyChart (121 [IQR 32-270.5]) than MyChart users who were not readmitted (91 [IQR 26-205]; P<0.0001). Multivariable regression analysis demonstrated that MyChart use was associated with readmission (odds ratio 1.57, 95% CI 1.49-1.70; P<0.0001). Conclusion: Among patients with AF, MyChart use was associated with higher readmissions in this single-center cohort. Use and benefit of bespoke portals require further study.