Glucose Patterns in Very Old Adults: A Pilot Study in a Community-Based Population

Abstract

Context:

Continuous glucose monitoring (CGM) provides nuanced information on glucose patterns, but data in very old adults are scarce.

Objective:

To evaluate CGM patterns in very old adults.

Design:

Pilot study.

Setting:

Participants recruited from one center during visit 7 (2019) of the community-based Atherosclerosis Risk in Communities (ARIC) Study.

Participants:

We enrolled 27 adults (8 with type 2 diabetes and 19 without diabetes) who wore a CGM sensor (Abbott Libre Pro) for up to 14 days. Clinical and laboratory measures, including hemoglobin A1c (HbA1c), were obtained.

Main Outcomes:

Mean CGM glucose, standard deviation (SD), coefficient of variation (CV), time-in-range (TIR) 70–180 mg/dL, and hypoglycemia.

Results:

Mean age was 81 (range 77–91 years) and mean CGM wear time was 13.2 days. In persons without diabetes, there was a wide range of CGM parameters: range of mean glucose, 83.7–124.5 mg/dL, SD 12.2–27.3 mg/dL, CV 14.0%–26.7%, and TIR 71.1%–99.5%. In persons with diabetes, the range of mean CGM glucose was 105.5–223.0 mg/dL, SD, 22.3–86.6 mg/dL, CV 18.2%–38.8%, TIR 38.7%–98.3%. The Pearson's correlation of mean glucose with HbA1c was high overall (0.90); but, for some participants with similar HbA1c, glucose patterns differed substantially. There was a high prevalence of hypoglycemia (glucose <70 or <54 mg/dL) in both persons with and without diabetes.

Conclusions:

There was high feasibility and acceptability of CGM in very old adults. Low readings on CGM are common, even in nondiabetic older adults; the clinical relevance of these low values is unclear. CGM may provide complementary information to HbA1c in some older adults.