This study examined the risk of low blood glucose in type 1 diabetics treated with insulin degludec.

Patients with type 1 diabetes (T1D) must inject rapid-acting insulin and long-acting insulin each day. Long-acting insulin maintains blood glucose levels at a steady level. Insulin glargine (Lantus) is a long-acting insulin injected once daily. It slowly reduces blood glucose levels over 24 hours. Insulin degludec (Tresiba) is an ultra-long acting insulin which lasts for up to 40 hours. 

Hypoglycaemia occurs when blood glucose levels are dangerously low (below 3.9 mmol/L). This can particularly occur during or after exercise. T1D patients treated with insulin glargine have a higher risk of experiencing low blood glucose after exercise. Insulin degludec may be used as an alternative to insulin glargine. Therefore, it is important to ensure that is as safe as insulin glargine. It is believed that insulin degludec has a similar risk of low blood glucose to that of insulin glargine.

This study aimed to compare the risk of low blood glucose after exercise between insulin degludec and insulin glargine.

This study involved 39 T1D patients. All participants performed two 30 minute sessions of moderately intense exercise on a stationary bicycle. Blood glucose levels were measured during the exercise and up to 24 hours after. Prior to one exercise session participants received insulin degludec. Prior to the other session, participants were treated with insulin glargine. Insulin aspart  was used as a short-acting insulin for all patients. Sessions were separated by 1-3 weeks.

Changes in blood glucose levels in participants treated with insulin degludec were similar to those treated with insulin glargine. Average blood glucose levels during exercise were also similar in participants treated with insulin degludec (7.28 mmol/L) to those treated with insulin glargine (7.43 mmol/L).

No participant experienced low blood glucose during exercise. 13 participants treated with insulin degludec experienced low blood glucose after exercise. 15 participants treated with insulin glargine experienced low blood glucose after exercise.  

This study concluded that the risk of low blood glucose following moderately intense exercise is similar between insulin degludec and insulin glargine.

This study only investigated moderately intense exercise. Additional studies investigating safety during and after high intensity exercise should be performed.

Consult your physician regarding the risks and benefits of insulin degludec.