SAN FRANCISCO – Most patients with diabetes should aim to spend at least 17 hours a day – more than 70% of their time – in a blood glucose range of 70-180 mg/dL, according to
Time spent below 70 mg/dL should be less than 1 hour a day, under 4% of the time in other words, and time spent below 54 mg/dL – the cut point for potentially serious hypoglycemia – less than 15 minutes (1%). Time spent at or above 180 mg/dL should be less than 6 hours (25%) a day, and above 250 mg/dL – the cut point for potentially serious hyperglycemia – less than 1 hour and 15 minutes (5%).
The advice comes from an international panel of diabetologists, researchers, and patients convened at the Advanced Technologies and Treatments for Diabetes Congress in Berlin earlier this year.
The goal was to give clinicians and patients handy treatment targets for continuous glucose monitors (CGMs), something that has been missing until now. The targets “should be considered an integral component of CGM data analysis and day-to-day treatment decision making,” said lead author Tadej Battelino, MD, PhD, head of the department of pediatric and adolescent endocrinology at Ljubljana (Slovenia) University, who presented the guidelines at the meeting.
The ADA, the European Association for the Study of Diabetes, and other leading diabetes groups have endorsed them.
CGMs have always offered the promise of tighter glycemic control, and their use is expanding, but they still have not led to a robust improvement in diabetes management, and in at least one study, they actually deteriorated control. There has been doubt about how to use them.
Dr. Battelino and associates thought that the main problem was a lack of clear, easy-to-understand treatment goals. The ADA and others previously recommended a CGM target of 70-180 mg/dL, but stopped short of saying how long people should be in that and other ranges. The new guidelines close the gap by adding the key element of duration.
“We ... pretty much defined what we believe is a safe way to live with diabetes,” Dr. Battelino said at the meeting. The work was based on literature review and expert opinion.
He and his colleagues noted in their journal write-up that for many the goals will be aspirational, but patients and doctors should not give up. The important thing is incremental change, with the hope of eventually meeting the targets. Even a small time-in-range increase reduces the risk of retinopathy and nephropathy, and improves hemoglobin A1c levels.
“You don’t have to get there all at once. Everyone needs to know that, whether they’re 14 or 44,” said coauthor Irl B. Hirsch, MD, chair of diabetes treatment and teaching at the University of Washington, Seattle, who moderated Dr. Battelino’s presentation.
To make the guidelines operational, the team created a simple, intuitive version of the ambulatory glucose profile they hope will be accepted as the new standard by CGM makers and included in device software. It reports the percentage of time in the 70-180 mg/dL range in green, the percentage below range in red, and the percentage above range in yellow. With a glance, both patients and doctors will know what is going on day by day, and what, if anything, needs to change.
The time-in-range bar was set at 50% for older and sicker patients, but their time-below-range goal was reduced from 4% to 1%, to emphasize the need to prevent hypoglycemia.
The target range was lowered for pregnant women to 63-140 mg/dL at least 70% of the time, because blood glucose levels are lower in pregnancy. However, “greater emphasis should be placed on getting to goal as soon as possible” with pregnant women and those planning to get pregnant, the panel said.
The work was funded by a number of companies, including Abbott, AstraZeneca, Dexcom, Eli Lilly, Medtronic, and Novo Nordisk. Dr. Battelino, Dr. Hirsch, and their coauthors reported various ties to those and other companies.
SOURCE: Battelino T et al. Diabetes Care. 2019 Jun 8. doi: 10.2337/dci19-0028.