Resource Utilization Among Portal Users Who Send Messages: A Retrospective Cohort Study

To examine the association between patients' use of online health portal-based secure messaging and the likelihood of traditional encounters (office visits and telephone calls) and to identify patient characteristics associated with use of the messaging feature of health portals.

This retrospective cohort study used EHR data from 80,801 patients aged 18 and older to determine traditional encounter rates among portal users who sent at least 1 message compared to those who sent none. Association between the number of messages sent and number of traditional encounters, while accounting for other covariates (including number of traditional encounters the year before account activation and other patient characteristics) was examined using a hurdle negative-binomial (NB) model.

In the year after their portal account activation, 22,789 (28%) patients sent at least 1 message (median = 3, mean = 5.38). Patients who sent messages were more likely to be female (63.9% vs 58.0%, P <0.001), white (92.2% vs 90.0%, P <0.001), and have depression (27.0% vs 24.2%, P <0.001) than those who sent none. We observed a positive association between sending messages and number of traditional encounters. Patients who sent messages were more likely to have a traditional encounter and have more traditional encounters in the year after account activation than those who sent none (mean 17.6 vs 11.4, P <0.001); they also had more in-person office visits (7.6 vs 5.0, P <0.001) and telephone calls (9.9 vs 6.4, P <0.001)) when examined separately.

Our study adds to the growing literature that EHR messaging is associated with increased traditional resource utilization. This has the potential to add to workload while diminishing productivity and increasing the risk of staff and physician burnout. Health systems should prepare for the increased visits and calls expected as more patients use secure messaging.