Discussion
generalised, hypoglycaemia
EVENTS, TYPE 1 DIABETES, NOCTURNAL HYPOGLYCAEMIA, HYPOGLYCAEMIA
The main finding of this study is that adjustment of insulin degludec dosing after aerobic exercise performed in the afternoon had no effect on the incidence of subsequent nocturnal hypoglycaemia in people with type 1 diabetes. While next-day time below range was slightly reduced in the 40% dose reduction group, this did not translate to fewer hypoglycaemic events. Postponement of degludec to the next morning at a 20% lower dose led to more time above range and less time in range during that day, as well as slightly more time below range on the subsequent second day. Altogether, these results do not support dose adjustments of degludec in people with type 1 diabetes after afternoon aerobic exercise.Two recent studies have reported a relatively low incidence of nocturnal hypoglycaemia after aerobic exercise in people with type 1 diabetes using insulin degludec [Heise et al reported insulin glargine and insulin degludec to have a similar (nocturnal) hypoglycaemic risk profile after performing aerobic exercise of moderate intensity in people with type 1 diabetes, without insulin dose reductions [For people with type 1 diabetes, the risk of hypoglycaemia is increased for at least 24 h after aerobic exercise, in particular, when performed in the afternoon [We chose postponement of insulin degludec as one of the dosing adjustment regimens because of previous data showing that alternating degludec dosing at flexible intervals of 8 to 40 h provided about similar glycaemic control to dosing every 24 h [Strengths of our study are the randomised crossover study design, the robust and highly reproducible exercise protocol, the use of CGM and the daily life setting, all of which are relevant in the context of the potential need for dose adjustments.Our study also has limitations. First, it may be questioned to what extent our results can be generalised to people performing morning exercise or injecting degludec in the morning. However, morning exercise leads to a lower risk of late-onset hypoglycaemia compared with afternoon exercise in people with type 1 diabetes on insulin pump therapy [In conclusion, adjustment of insulin degludec dosing after aerobic exercise in the late afternoon has no effect on subsequent nocturnal hypoglycaemia in people with type 1 diabetes. In fact, postponing the administration of degludec leads to more time above range, which underscores the importance of adhering to insulin degludec dosing around exercise, especially when insulin doses are low. Adjustments in meal-related short-acting insulin both before and after exercise may be advisable for people using degludec, but our data do not provide support for standard insulin degludec dose adjustment after exercise in people with type 1 diabetes. These data add evidence for the ease of use of insulin degludec for most people with type 1 diabetes who want to engage in aerobic exercise.