Variations in ambulant glucose tied to severe hypoglycaemia, unawareness of episode in T1D

In patients with type 1 diabetes (T1D), the coefficient of variation (CV) of ambulant glucose levels appears to be correlated with severe hypoglycaemia episodes and unawareness of hypoglycaemia, a recent Japan study has found.

“Patients with high glucose CV and low glycated haemoglobin (HbA1c) are at high risk of such adverse events, and their treatment strategies should be reviewed.”

Using a self-administered questionnaire, researchers assessed medications, complications, and events associated with severe hypoglycaemia episodes in 1,619 patients with T1D. Hypoglycaemia unawareness was defined as having blood glucose ≤70 mg/dL without symptoms, or needing the help of a third party to identify that such was a hypoglycaemic episode.

Multiple logistic regression showed that blood glucose CV was significantly associated with both severe hypoglycaemia (odds ratio [OR] per 1-percent change, 4.36, 95 percent confidence interval [CI], 1.52–12.52) and being unaware of a hypoglycaemic episode (OR per 1-percent change, 7.16, 95 percent CI, 3.45–14.94).

A history of unawareness of a hypoglycaemia episode was also found to be a significant predictor of severe hypoglycaemia (OR, 6.57, 95 percent CI, 4.06–10.64).

Meanwhile, such unawareness was also predicted by HbA1c level, an acute T1D subtype, and a history of severe hypoglycaemia.

Study limitations included its use of questionnaires to assess hypoglycaemic episodes, lack of quantitative confirmation, and the failure to assess other medications taken aside from insulin. Future efforts are needed to control for the uncertainties that these limitations might have introduced.