Physiologic Insulin Delivery with Insulin Feedback: A Control Systems Perspective

Individuals with type 1 diabetes mellitus must keep good control of their glucose levels in order to avoid the complications associated with the disease. This is no easy task, however, since even a highly motivated patient can have a hard time doing so. Moreover, this imposes a significant burden, as patients must be constantly monitoring and adjusting their treatment. For this reason, research into a closed-loop insulin delivery system has been of interest for several decades. This paper provides an overview, from a control systems perspective, of the research and development effort of a particular algorithm — the external Physiologic Insulin Delivery system. In particular the introduction of insulin feedback, as suggested by β-cell physiology, is covered in detail. A summary of human clinical trials is provided in the context of the evolution of this algorithm, and this paper outlines some of the research avenues that show particular promise.