Why Patient Portal Messages Indicate Risk of Readmission for Patients with Ischemic Heart Disease

Online portals enable patients to exchanging messages with healthcare providers. After discharge, patients message providers to ask questions and report problems. Care providers read and respond accordingly, which requires a non trivial amount of human effort and is unlikely to scale up as portals become more popular. Automatically detecting when a message indicates a worsening in a patient's condition can assist providers to identify patients at risk of readmission. We investigated the association between messages that patients, diagnosed with ischemic heart disease, sent after discharge and the risk of readmission. We studied 4,052 messages sent after discharge for 1,552 patients. We represented messages using inferred latent topics, linguistic features (e.g. emotions, activities), and clusters of medical terms. Our analysis indicates that mentioning medication dosage and additional procedures are associated with readmission. Moreover, patients who were readmitted rarely mentioned leisurely activities or described their insights about their health information.