Continuous Glucose Monitors Improve QALYs for Type 1 Diabetic Patients

By Kurtis Chien

For people suffering from type-1 diabetes, management of blood-glucose levels can be an expensive and time-consuming process. A recent study by researchers at the University of Chicago Medical Center found that, of the methods used to monitor blood-glucose levels, continuous glucose monitors provide the best health outcomes. (1)

Continuous glucose monitors use sensors underneath the skin to test glucose levels in the blood. (2) The data is sent to a device or even a smartphone app for the user to view. (2) Since data is taken continuously, trends in blood-glucose levels can give the user insight on how to adjust their food intake or daily activities. (2) However, users still have to prick their fingers for blood testing at least twice a day in order to calibrate their monitors. (2)

The study tracked costs and outcomes of a group of 158 patients with type-1 diabetes over the course of six months. (1) Two-thirds of the patients used continuous glucose monitors, and the rest used a finger prick method to test blood-glucose levels with test strips and meters. (1) After six months, the researchers found that patients using continuous glucose monitors experienced fewer low blood sugar events, as well as greatly reduced hemoglobin A1C levels. (1) A1C testing measures glucose binding to red blood cells, and high A1C levels are generally associated with diabetic conditions. (3)

Continuous glucose monitors proved more expensive over the six month period, with the average direct and indirect costs totaling to $11,032. (1) For reference, the costs of using test strips added up to about $7,236. (1) However, the researchers also analyzed QALYs, or quality-adjusted life years, for each patient. (1) QALYs measure how much time a person lives without any severe health-related impairments, and can be used to calculate overall disease burden. (1) The study found that the health outcomes brought about by use of continuous glucose monitors raised QALYs by 13.32, whereas use of test strips raised QALYs by 12.78. (1) This means that continuous glucose monitors can improve health outcomes by more than half a year of impairment-free health as compared to just using test strips. (1) Furthermore, the total cost per QALY was exceptionally cost-efficient, and could see coverage by most U.S. insurance plans. (1)


  1. Wan, W., Skandari, M. R., Minc, A., Nathan, A. G., Winn, A., Zarei, P., . . . Huang, E. S. (2018). Cost-effectiveness of Continuous Glucose Monitoring for Adults with Type 1 Diabetes Compared With Self-Monitoring of Blood Glucose: The DIAMOND Randomized Trial. Diabetes Care, Dc171821. doi:10.2337/dc17-1821
  2. Continuous Glucose Monitoring. (n.d.). Retrieved April 16, 2018, from
  3. The A1C Test & Diabetes. (2014, September 01). Retrieved April 16, 2018, from