Plasma glucose and hypoglycaemia following exercise in people with Type 1 diabetes: a comparison of three basal insulins

Aim The aim of this study was to compare the effects of exercise on plasma glucose excursions when using each of three basal insulins in people with Type 1 diabetes. Research design and methods This was a multinational, open-label, randomized, three-period, crossover clinical trial. People with Type 1 diabetes [n = 51, age 39 +/- 10 (+/- sd) years, 67% men] managed with mealtime plus basal insulin regimens, were exercised for 30 min, 5 h after the last mealtime and basal insulin injection when using insulin detemir, insulin glargine or neutral protamine Hagedorn (NPH) insulin. Results There were no significant differences in the plasma glucose excursions during or for 150 min after exercise. During 30 min exercise, five (11%) participants on insulin detemir developed minor hypoglycaemia, six (12%) for NPH and 18 (38%) for glargine. From the end of exercise to 150 min, five (11%) on insulin detemir developed minor hypoglycaemia, seven (14%) for NPH and nine (19%) for glargine. In total, from start of exercise to 150 min after exercise, 10 (21%) participants on insulin detemir experienced minor hypoglycaemia as compared with 13 (27%) for NPH and 27 (57%) for glargine (P < 0.001 glargine vs. detemir and NPH). Maximum plasma cortisol levels were lower on detemir and NPH than glargine. Conclusions Insulin detemir was associated with less hypoglycaemia than insulin glargine but not NPH insulin in relatively well-controlled people with Type 1 diabetes during and after exercise.