Risk of progression of Prediabetes to Diabetes minimal in elderly: JAMA

The term prediabetes is used to identify individuals at increased risk for diabetes. It is defined by ranges of disordered glucose values between normal and diabetes (eg. hemoglobin A1c levels, 5.7%-6.4%). In 2017, 352 (7.3%) million adults were living with prediabetes worldwide, and this number is expected to increase to 587 million (8.3%) by 2045. Prediabetes is more common in older than younger people; about 48% of U.S. adults aged ≥65 years had this condition in 2010. However, the natural history of prediabetes in older age is not well characterized. Therefore, researchers of America conducted a study, to compare the different prediabetes definitions and characterize the risks of prediabetes and diabetes among older adults in a community-based setting.

It was a prospective cohort analysis of 3412 older adults without diabetes from the Atherosclerosis Risk in Communities Study (baseline, 2011-2013). Researchers contacted participants semiannually through December 31, 2017, and followed them for 5 visits between January 1, 2016, and December 31, 2017. They defined prediabetes by a glycated hemoglobin (HbA1c) level of 5.7% to 6.4%, impaired fasting glucose (IFG) level (FG level of 100-125 mg/dL), either, or both. The major outcome assessed was incident total diabetes (physician diagnosis, glucose-lowering medication use, HbA1c level ≥6.5%, or FG level ≥126 mg/dL).

Key findings of the study:

♦ During the 6.5-year follow-up period, researchers noted 156 incident total diabetes cases (118 diagnosed) and 434 deaths.

♦ Upon analysis, they noted that

• 44% had HbA1c levels of 5.7% to 6.4%,
• 59% had IFG,
• 73% met the HbA1c or IFG criteria, and
• 29% met both the HbA1c and IFG criteria.

♦ Among participants with HbA1c levels of 5.7% to 6.4% at baseline, they noted 9% progressed to diabetes, 13% regressed to normoglycemia (HbA1c, <5.7%), and 19% died.

♦ Among those with IFG at baseline, they noted that 8% progressed to diabetes, 44% regressed to normoglycemia (FG, <100 mg/dL), and 16% died.

♦ Of those with baseline HbA1c levels less than 5.7%, they found 17% progressed to HbA1c levels of 5.7% to 6.4% and 3% developed diabetes.

♦ Among those with baseline FG levels less than 100 mg/dL, they observed 8% progressed to IFG (FG, 100-125 mg/dL) and 3% developed diabetes.

The authors concluded, "In this community-based cohort study of older adults, the prevalence of prediabetes was high. However, during the study period, regression to normoglycemia or death was more frequent than progression to diabetes. These findings suggest that prediabetes may not be a robust diagnostic entity in older age."

For further information:

https://jamanetwork.com/journals/jamainternalmedicine/article-abstract/2775594