Continuous glucose monitors (CGM) offer significant, daily benefits to people with type 1 diabetes, providing near-real time measurements of blood sugar levels, but they can be expensive. A new study by researchers from the University of Chicago Medicine, based on a six-month clinical trial, finds that use of a CGM is cost-effective for adult patients with type 1 diabetes when compared to daily use of test strips. The results are well within the thresholds normally used by insurance plans to cover medical devices. During the trial, CGMs improved overall blood glucose control for the study group and reduced hypoglycemia — low blood sugar episodes.
The study also simulated the costs and health effects of CGM use over the expected lifetime of patients. It showed that CGMs increased quality of life by extending the amount of time patients enjoy relatively good health, free of complications.
The monitor uses a tiny sensor inserted under the skin to test blood sugar levels every few minutes throughout the day, which it wirelessly sends to a monitor. The first generation of CGMs transmitted data to a stand-alone electronic device that looks like a pager, but newer models can work with apps on smart-phones and smartwatches. This provides near-real time information and allows diabetics to adjust their physical activity, food intake, or insulin levels quickly, preventing severe high or low blood sugar episodes.
The researchers also used a statistical model to simulate costs and health effects of CGM use over the average expected lifetimes of patients. The model calculated a value called quality-adjusted life years (QALYs) for each patient, which represents the amount of time they live free of any complications or serious medical incidents. In the lifetime analysis, the CGM was projected to reduce the risk of complications from type 1 diabetes and increase QALYs by 0.54, basically adding six months of good health.
The analysis calculated an incremental cost-effectiveness ratio, which shows the difference in costs for a treatment, in this case the CGM vs daily test strips, over the health benefit it adds — the quality of life years. The cost-effectiveness ratio for the CGM was about 0,000 per QALY for the overall population. This is well below the threshold insurance plans and government agencies such as Medicare normally use to decide whether or not to cover a new treatment or medical device. The ratio was calculated based on the recommendation to use a CGM sensor for seven days, but if that use was extended to 10 days, as many people do, that ratio was reduced to about ,000 per QALY. For more information, contact