Burden and Risk Factors of CGM-Detected Hypoglycemia in Older Adults With Type 2 Diabetes

Comprehensive data on the burden of biochemical hypoglycemia in older adults with type 2 diabetes are lacking. We seek to characterize the burden and risk factors for hypoglycemia detected by continuous glucose monitoring (CGM) in older adults with type 2 diabetes.

A cross-sectional analysis of 315 older adults with type 2 diabetes who attended visit 9 of the Atherosclerosis Risk in Communities Study (2021-2022). We examined rates of Level 1 hypoglycemia (< 70 mg/dL) and percentage meeting recommended targets for hypoglycemia (< 1% of time). We identified risk factors for CGM-detected hypoglycemia by comparing the median time spent in hypoglycemia across subgroups. All analyses were stratified by high-risk medication use (insulin/sulfonylureas vs. not).

Of the 315 participants with type 2 diabetes (mean age 83 years, 55% women, 41% Black adults), 32.4% were using insulin or sulfonylureas. Among individuals using these high-risk medications, the median time spent in hypoglycemia was 3.4%, and ~66% of participants spent more than 1% of the time with CGM glucose < 70 mg/dL. Hypoglycemic episodes typically occurred overnight and lasted a median of ~1.5 h among individuals using insulin or sulfonylureas. CGM-detected hypoglycemia was low in participants not using high-risk medications (median time spent in hypoglycemia: 0.7%). In unadjusted analyses, cardiovascular disease, cognitive impairment, poor physical functioning, and chronic kidney disease were associated with increased time spent in hypoglycemia, regardless of high-risk medication use.

There may be a substantial burden of unrecognized CGM-detected hypoglycemia in very old adults with type 2 diabetes using high-risk medications in the general population. Hypoglycemia may also be present among persons not on high-risk medication, but the burden is much lower. Further research is needed to clarify the clinical significance of these hypoglycemic episodes.