Biochemical Hypoglycemia Associated with Risk of Hypoglycemia

Glycated hemoglobin (HbA1c) is primarily a measure of hyperglycemia, but it provides no indication of the frequency or severity of hypoglycemia.

However, combining HbA1c with continuous glucose monitoring (CGM) provides not only measures of hypoglycemia and hyperglycemia but also information about the patterns of glycemia over the course of the day. Severe hypoglycemia (SH) may result in a variety of symptoms including clumsiness, trouble talking, confusion, loss of consciousness, seizures or death. A feeling of hunger, sweating, shakiness and weakness may also be present.

Scientists at the Jaeb Center for Health Research (Tampa, FL, USA) and their colleagues, analyzed data collected from Diabetes Control and Complications Trial. Glycemic data used in the analyses included the quarterly 7-point glucose measurements and recorded SH events. The 7-point testing consisted of blood samples collected in capillary tubes pre- and 90 min post meals and at bedtime that were sent to the central laboratory. For each 7-point testing day, the frequency of values <70 and <54 mg/dL was computed.

The team found that the risk of SH during a 3-month period was substantially higher when there was at least one hypoglycemic blood glucose value in the preceding 7-point profile, with similar results seen for both the 70 mg/dL (rate ratio = 3.0) and 54 mg/dL (rate ratio = 2.7) thresholds. The risk of an SH event during the 3-month period was more than twofold greater when there was at least one hypoglycemic blood glucose measurement on the 7-point testing, and risk increased further when there was more than one hypoglycemic blood glucose concentration.

The authors concluded that the occurrence of biochemical hypoglycemia <70 or <54 mg/dL is associated with an increased risk of SH. For this reason as well as the deleterious effects of hypoglycemia on glucose counter-regulation and hypoglycemia awareness, cognition, quality of life, and arrhythmias, it is important in diabetes management to avoid hypoglycemic glucose levels as much as possible. Satish Garg, MD, a Professor of Medicine and Pediatrics, said, “Severe hypoglycemia is a significant hurdle for intensifying insulin therapy in patients with T1D. Beck and colleagues emphasize the increased risk of future severe hypoglycemia in patients with any level of biochemical hypoglycemia.” The study was published on January 8, 2019, in the journal Diabetes Technology & Therapeutics.

Related Links:
Jaeb Center for Health Research