Can morning blood glucose levels predict low blood glucose at night in diabetics?

This study examined whether glucose levels can predict night-time hypoglycaemia in type 1 diabetics.

Lower blood glucose (sugar) levels in patients with type 1 diabetes can reduce the risk of developing complications. However, patients then have a higher risk of experiencing hypoglycemia (dangerously low blood glucose levels). Patients may have asymptomatic (unaware of symptoms) hypoglycemia. Patients may also experience symptomatic (aware of symptoms) hypoglycemia.

Fasting blood glucose (FBG) is a measure of blood glucose levels in an individual who has not eaten anything for 8 hours. FBG levels may be able to predict low blood glucose at night. Variation in blood glucose levels after breakfast may also predict low blood glucose at night.

This study aimed to determine whether morning glucose levels were associated with low blood glucose at night.  

This study involved 64 T1D patients. 23 participants experienced asymptomatic hypoglycemia. 41 participants were aware of their hypoglycemia. All participants were treated with short-acting insulin after meals and also received long-acting insulin. Blood glucose levels were monitored using a continuous glucose monitor (CGM). A CGM is a device which measures blood glucose levels in real-time.

FBG levels were lower in participants who had night-time low blood glucose (118 mg/dL). Participants who did not have low blood glucose at night had a higher FBG (179 mg/dL). High variation in blood glucose levels (greater than 78 mg/dL) two hours after breakfast could predict low blood glucose at night.

This study concluded that the range of blood glucose levels after breakfast coutd predict low blood glucose at night. FBG levels could also predict low blood glucose at night.