DiAs web monitoring: a real-time remote monitoring system designed for artificial pancreas outpatient trials

Abstract

Background: Developments in an artificial pancreas (AP) for patients with type 1 diabetes have allowed a move toward performing outpatient clinical trials. "Home-like" environment implies specific protocol and system adaptations among which the introduction of remote monitoring is meaningful. We present a novel tool allowing multiple patients to monitor AP use in home-like settings.

Methods: We investigated existing systems, performed interviews of experienced clinical teams, listed required features, and drew several mockups of the user interface. The resulting application was tested on the bench before it was used in three outpatient studies representing 3480 h of remote monitoring.

Results: Our tool, called DiAs Web Monitoring (DWM), is a web-based application that ensures reception, storage, and display of data sent by AP systems. Continuous glucose monitoring (CGM) and insulin delivery data are presented in a colored chart to facilitate reading and interpretation. Several subjects can be monitored simultaneously on the same screen, and alerts are triggered to help detect events such as hypoglycemia or CGM failures. In the third trial, DWM received approximately 460 data per subject per hour: 77% for log messages, 5% for CGM data. More than 97% of transmissions were achieved in less than 5 min.

Conclusions: Transition from a hospital setting to home-like conditions requires specific AP supervision to which remote monitoring systems can contribute valuably. DiAs Web Monitoring worked properly when tested in our outpatient studies. It could facilitate subject monitoring and even accelerate medical and technical assessment of the AP. It should now be adapted for long-term studies with an enhanced notification feature.

Figure 1.

Architecture of a remote monitoring system: one or several devices such as an AP send data in real time to a remote server using a 3G or Wi-Fi network. Data are then stored and displayed through an application accessible from a laptop, a tablet, or a smartphone connected to the Internet.

Figure 2.

Communication process between DiAs NS and the DWM application. Network Service looks for new data coming from the AP platform and sends them to the remote server using a secured HTTP request. The data collection module of the remote server ensures the reception and storage of time-stamped values into a database. Finally, data are organized and displayed through a UI.

Figure 3.

Overload tests performed with Apache JMeter. Number of simultaneous requests increases step by step to reach a maximum of 100 active connections, with 10 requests per second (red line). Despite this increase, server response time remains stable (blue line).

Figure 4.

Single patient monitoring screen. Continuous glucose measurements (blue dots) and insulin bolus (green bars) are represented in a chart. Current state of AP, current CGM value and trend, last alerts, and insulin amounts are displayed on the right-hand side. Traffic lights representing hyperglycemia and hypoglycemia risk are on the left-hand side. Other data are accessible from horizontal tabs menu.

Figure 5.

Simultaneous patients monitoring screen. Here, five patients are monitored at a time, and the system alerts that one of the patient is at risk for hypoglycemia (red box).