CGM Linked to Lower Mortality and Cardiovascular Risk in Basal Insulin-Treated Type 2 Diabetes: Study

People with type 2 diabetes (T2D) on basal insulin, starting continuous glucose monitoring (CGM) had a 44% lower risk of dying from any cause after one year compared with those who did not use CGM, with the risk being 35% lower after two years, according to an analysis of patient data being presented at the Annual Meeting of The European Association for the Study of Diabetes (EASD) in Milan, Italy (Sept 28 – Oct 2).

The findings provide the first evidence of an association between advanced CGM technologies and lower risk of death in people living with T2D receiving therapy with basal insulin with or without noninsulin diabetes medications, and also show a reduced risk of cardiovascular events, say researchers.

Estimates suggest that around 7% of the 405 million people with T2D, or nearly 30 million people globally, require insulin therapy. Keeping glucose levels within the target range can be difficult. Over time, consistently high glucose levels can increase the risk of serious complications, including heart disease, blindness and stroke.

CGM uses a small sensor worn on the skin to measure glucose levels and transmit the readings to a mobile device, dedicated reader, or automated insulin delivery system. This allows people to monitor their glucose levels at all times, helping them make informed adjustments to their lifestyle or insulin treatment.

CGM has transformed care for people with type 1 and type 2 diabetes and has been shown to improve blood glucose control, including episodes of hypoglycaemia (dangerously low blood sugar levels). However, in people living with T2D, its potential role in reducing other long-term complications is less clear.

To find out more, researchers from Abbott and collaborating institutions used the Truveta platform, a database that includes anonymised electronic health records of over 140 million Americans, to assess the risk of death from any cause, as well as first and recurrent macrovascular events—including heart attack, heart failure, stroke or transient ischaemic attack (TIA), and peripheral artery disease—in adults with T2D receiving basal insulin therapy between 1st January 2017 and 18th March 2024.

The target trial emulation study compared 13,935 patients who filled a first prescription for CGM with 13,935 non-CGM users. The cohorts were matched on 29 patient characteristics at the start of the study to reduce confounding, including, age, sex, ethnicity, duration of diabetes, severity of diabetes complications, blood sugar control as measured by HbA1c levels, other comorbidities, use of medications, frequency of healthcare use, and use of blood glucose monitors. The average age of participants was 58 years and 47% were female.

Overall, CGM use was associated with a lower risk across all outcomes studied both a year and two years later.

At 12 months, CGM users were 44% less likely to die from any cause than those not using CGM, with death occurring in 1.16% of CGM users compared with 2.09% of non-CGM users. At 24 months, the risk of death from any cause was 35% lower among CGM users (2.12% vs 3.26%).

Similarly, the risk of experiencing a new macrovascular event was 26% lower among CGM users at 12 months than among non-CGM users (1.03% vs 1.39%), and 24% lower at 24 months (1.64% vs 2.17%).

The analysis also found that the rate of recurrent macrovascular events was 35% lower among CGM users at 12 months, and 36% lower at 24 months.

Notably, the rate of heart failure hospitalisations was around half as high among CGM users at both 12 months (54% lower) and 24 months (47% lower); see Table 1 in the Notes to Editors.

The findings remained consistent across several sensitivity analyses, including analyses that excluded the COVID-19 period and excluded deaths occurring within the first 90 days.

“Our study suggests that CGM can make a real difference to the long-term health of people living with type 2 diabetes who require insulin and may help reduce the risk of early death,” said Professor Jochen Seufert from the University Hospital of Freiburg in Germany, who led the research.

“These findings strengthen the case for expanding access to CGM for people with type 2 diabetes on basal insulin therapy who could benefit from it. It is vital that we work towards fair and equitable access to diabetes technology, alongside the support people need to use it effectively, so that no one is left behind.”

The authors point out that, as an observational study, the research cannot determine what specifically caused the lower rates of cardiovascular events and death, and the possibility of unmeasured confounding cannot be excluded despite participants being matched on 29 factors that could affect the results. They also acknowledge other limitations, including that changes to medications and other time-varying clinical measures were not examined during follow-up. In addition, the study population may not be representative of all adults with T2D receiving basal insulin, and they say that larger prospective studies are needed to confirm and build on these findings.

Reference:

New evidence links continuous glucose monitoring with lower risk of death and cardiovascular events in people with type 2 diabetes treated with basal insulin, European Association for the Study of Diabetes, Meeting: Annual Meeting of the European Association for the Study of Diabetes (EASD).