Telemonitoring blood pressure by secure message on a patient portal: Use, content, and outcomes

Introduction: Secure messages on a patient portal allow patients to asynchronously communicate with their healthcare teams. Patients can use this mode of communication to transmit data such as home blood pressure (BP) measurements. Materials and Methods: In this retrospective study, we examined 52,373 secure messages for content related to home BP monitoring. Text searches of the messages were followed by manual message review to identify BP-related messages. Two physicians independently reviewed a sample of these messages and the provider responses. Results: Of 19,545 total message users, there were 4,412 message users with a diagnosis of hypertension and 365 who sent BP-related messages. Of the 52,373 secure messages, 624 messages (1.2%) contained information about home BP. Providers responded to messages with a change in medication dose or a prescription in 17%. When new medications were recommended, providers needed more pharmacy information in 53%. Messages contained a concern about high BP in 27% and concern about low BP in 8.5%. BP data in patient messages only attained American Heart Association-endorsed measurement criteria in 7% of messages. Conclusions: Patient-generated secure messages with BP data often result in message responses from providers for a BP medication dose change or a new prescription. Despite its increasing use, BP management by secure message has significant limitations and might be better served by BP virtual visits (e-visits) containing specific data requirements such as an average BP value from at least 12 readings and a preferred pharmacy for a prescription.