Welcome to our first newsletter from Memorial Endocrinology and Diabetes concerning recent advances in the treatment of diabetes and other hormonal disorders. Endocrinology is the specialty which focuses on hormonal and metabolic disease. Our goal is to place a new handout, written by one of our three physician endocrinologists, concerning new advances in endocrinology on our website every two months (bimonthly). Dr. Varughese, Dr. Chaudhry, and I are genuinely excited about the new medications and technology which have transformed the treatments of diabetes, obesity (overweight), and other endocrine disorders. Through these newsletters, we hope to keep you informed about these exciting new developments in these areas.
The topic of this newsletter (January, 2023) will focus on recent advances in the testing of home blood sugar (glucose) levels. Many of our patients with diabetes who take insulin are already using a continuous glucose monitor (CGM) to continuously check and record the level of glucose in their subcutaneous tissue. Subcutaneous tissue is the fatty layer of tissue just below the surface of your skin. The subcutaneous levels of glucose have been shown to correlate very well with blood glucose levels. The newer CGM devices do the following things:
- Continuously check and record glucose levels.
- No longer require calibration by fingerstick glucose testing.
- Provide a very useful and understandable visual printout of your glucose levels over
time, revealing the patterns of when high glucose levels and low glucose levels are
most likely to occur.
- Calculate the percent of time your glucose levels are in good control and the percent of
time glucose levels are high or low. Current guidelines recommend that for most
patients, glucose levels should range from 70 to 180 for 70% of the time in a 24-hour
- Show the current glucose level and indicate whether the glucose is trending upward or
downward, and how fast.
- Are able to forward your glucose levels continuously to the newer insulin pumps, which
regulate the insulin infusion rate based on the blood sugar. The newest insulin pumps
decrease the insulin infusion rate if the glucose level is trending low and will shut off the
insulin flow completely if the glucose level reaches a critical low value (usually set at
- Perhaps most importantly, new CGM devices send an audible alarm to your cellphone
or receiver to notify you of critical high or low glucose levels. These alarms have greatly
reduced the risk of severe hypoglycemia.
The capabilities of the newest CGM devices have, in my opinion, transformed the treatment of type 1 insulin-requiring diabetes more than any other recent advance. This technology has driven the development of these next generation insulin pumps with automated insulin delivery. Advances in automated insulin delivery mean that we now have within sight the “holy grail” of therapy for type 1 diabetes, which is the “artificial pancreas” technology long dreamed of with the potential to maintain normal or near normal glucose levels 24 hours per day with minimal effort and oversight required from the patient compared to times past.
I would like our patients to be familiar with the newest CGM devices which have recently been approved by the FDA. The first device is the new Freestyle Libre 3 CGM manufactured by Abbott Laboratories. The Freestyle Libre 3 incorporates several advances:
- Size – similar in size to two stacked pennies (amazingly small).
- Convenience – automatically sends current glucose data to your cellphone via
Bluetooth (no manual checking or “wanding” required).
- Accuracy – just over 7% variation in adults from laboratory glucose analyzers.
Fingerstick glucose checks have about a 15% variation from the laboratory glucose
A photo illustration of the new Freestyle Libre 3 is shown below:
The small size of the sensor is amazing and should help with privacy concerns and difficulties from traumatic sensor loss. The recommended location for the Libre sensors is on the side or back of the upper arm and their expected useful wearing time is 14 days. Another glucose sensor which has recently been approved by the FDA is the new Dexcom G7 (Generation 7) sensor. Dexcom has established an enviable reputation for reliability and accuracy, and is the sensor most commonly paired with the latest generations of insulin pumps. The advantages of the new Dexcom G7 sensor are:
- Small size – 60% smaller than the previous Dexcom G6 sensor.
- Separate attached transmitter – no longer required. The small G7 sensor transmits directly to a cellphone or receiver.
- Warm-up time – only 30 minutes.
- Integrates with the Apple watch and other electronic devices.
- Able to share continuous glucose data with other family members and friends, enhancing safety especially for children and impaired adults.
A photo of the new Dexcom G7 sensor and its cellphone app is shown below:
Newly developed sensors for continuous glucose monitoring have transformed the treatment for persons with type 1 and insulin-requiring diabetes, and greatly reduce the risk of severe hypoglycemia. We are very excited about this technology. If you have diabetes which requires insulin therapy and are not using a continuous glucose monitor, please talk to one of our physicians about these devices.
— Donald F. Gardner, MD