How Continuous Glucose Monitors Are Changing Diabetes Care

From news.med.miami.edu

Summary

For years, doctors have relied on a blood test called HbA1c (or A1c) to monitor blood sugar for people with diabetes. Now, researchers are moving toward continuous glucose monitoring (CGM) as a way for patients and doctors to see the full picture, leading to better care and new possibilities.

While HbA1c has long been useful, it offers only an average and doesn’t reveal the ups and downs of a person’s blood sugar. A new study published in Endocrine Practice and co-authored by Rodolfo Galindo, M.D., and Ron Varghese, M.D., both associate professors in the Division of Endocrinology, Diabetes and Metabolism at the University of Miami Miller School of Medicine, explored the expanding role of continuous glucose monitoring technology. 

“For years, the medical and patient community relied on single-point glucose checks, whether via a blood test or finger stick capillary blood testing,” Dr. Galindo said. “This approach provided a limited assessment of glucose regulation and changes in humans. Notably, we were not able to acknowledge that until the expansion of CGM use in research and clinical practice. Here, we realized we knew very little about glucose regulation, patterns, trends and tendencies in humans.”

Understanding Continuous Glucose Monitoring

Unlike finger stick tests, which give just a single reading, continuous glucose monitoring devices record thousands of measurements every day. Patterns, such as blood sugar dropping overnight or spiking after meals, that might otherwise be missed are revealed. 

“The use of CGM has helped in early detection of both high and low glucose in patients with diabetes, especially with chronic kidney disorders,” Dr. Varghese said. “Earlier detection of changes in glucose in real time helps patients to pre-empt low glucose by taking corrective measures at the appropriate time.”

HbA1c accuracy can be affected by anaemia, pregnancy or kidney problems. CGMs don’t have these limitations. They show real-time changes and help spot dangerous highs and lows that HbA1c can’t detect. 

Expanding the Role of CGMs

Dr. Galindo and Dr. Vargehese examined data from randomized controlled trials, observational cohorts and cross-sectional studies evaluating CGM in diverse populations. People with type 2 diabetes who used CGMs:

• Experienced significant improvements in their A1c levels

• Spent more time in the healthy range

• Faced fewer episodes of low blood sugar

Remarkably, some of these benefits persisted even after discontinuing the CGM. For patients with kidney disease, CGMs proved particularly reliable, catching hidden episodes of hypoglycaemia and hyperglycaemia during dialysis that traditional tests often missed.

“Without a doubt, CGM devices have revolutionized diabetes care and served as a pivotal step into the development of an artificial pancreas,” Dr. Galindo said. “The new frontier will be continuous monitoring of other human electrolytes like sodium, calcium, potassium or disease biomarkers like ketones that are already in regulatory approval stage.”  

The impact of CGM technology extended to other health conditions. People with sleep apnoea, for instance, often encounter unpredictable blood sugar swings, particularly during the night. CGMs provided valuable insights for doctors into how sleep disturbances influenced glucose levels. Similarly, CGMs helped tailor insulin doses for people with gastroparesis, making it easier to avoid dangerous fluctuations in blood sugar.

After weight-loss surgery, some patients were prone to sudden drops in glucose that were not detected by other tests. CGMs captured these events and helped predict which individuals would see improvement in their diabetes following surgery. In cases of insulinoma, a rare tumour that produces excess insulin, CGMs uncovered hidden episodes of low blood sugar and allowed doctors to monitor treatment more closely.

Through these varied applications, continuous glucose monitors are demonstrating their potential to enhance care in a range of clinical scenarios, far beyond traditional diabetes management.

A Clearer View of Blood Sugar

CGMs give patients and doctors a much clearer view of what’s happening with blood sugar, minute by minute. The tool improves safety by catching hidden highs and lows at an early stage. As medicine leans towards personalized care, doctors will be able to adjust treatments based on real patterns, not just averages. 

Patients can see clearly how food, exercise and sleep affect their blood sugar levels, helping them to make smarter choices and improve their quality of life. CGMs invite less guesswork, fewer surprises and more confidence in managing diabetes. 

“The use of CGM and over-the-counter availability of CGM has the potential to detect and transform the care of conditions like prediabetes and sleep disorders, and helps to tailor and modify diet in people who can notice changes in glucose in real time with the use of these devices,” Dr. Varghese said.

https://news.med.miami.edu/how-continuous-glucose-monitors-are-changing-diabetes-care/