Timing of insulin basal rate reduction to reduce hypoglycemia during late post-prandial exercise in adults with type 1 diabetes using insulin pump therapy: A randomized crossover trial

Diabetes Metab. 2019 Jun;45(3):294-300. doi: 10.1016/j.diabet.2018.08.002. Epub 2018 Aug 27.

Abstract

Aims: To compare the efficacy of three timings to decrease basal insulin infusion rate to reduce exercise-induced hypoglycaemia in patients with type 1 diabetes (T1D) using pump therapy.

Methods: A single-blinded, randomized, 3-way crossover study in 22 adults that had T1D > 1 year and using insulin pump > 3 months (age, 40 ± 15 years; HbA1c, 56.3 ± 10.2 mmol/mol). Participants practiced three 45-min exercise sessions (ergocyle) at 60% VO2peak 3 hours after lunch comparing an 80% reduction of basal insulin applied 40 minutes before (T-40), 20 minutes before (T-20) or at exercise onset (T0).

Results: No significant difference was observed for percentage of time spent < 4.0 mmol/L (T-40: 16 ± 25%; T-20: 26 ± 27%; T0: 24 ± 29%) (main outcome) and time spent in target range 4.0-10.0 mmol/L (T-40: 63 ± 37%; T-20: 66 ± 25%; T0: 65 ± 31%). With T-40 strategy, although not significant, starting blood glucose (BG) was higher (T-40: 8.6 ± 3.6 mmol/L; T-20: 7.4 ± 2.5 mmol/L ; T0: 7.4 ± 2.7 mmol/L), fewer patients needed extra carbohydrates consumption prior to exercise for BG < 5.0 mmol/L (T-40: n = 3; T-20: n = 5; T0: n = 6) as well as during exercise for BG < 3.3 mmol/L [T-40: n = 6 (27%); T-20: n = 12 (55%); T0: n = 11 (50%)] while time to first hypoglycaemic episode was delayed (T-40: 28 ± 14 min; T-20: 24 ± 10 min; T0: 22 ± 11 min).

Conclusion: Decreasing basal insulin infusion rate by 80% up to 40 minutes before exercise onset is insufficient to reduce exercise-induced hypoglycaemia.

Keywords: CSII; Exercise; Hypoglycaemia; Insulin pump; Type 1 diabetes.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Aged
  • Blood Glucose
  • Cross-Over Studies
  • Diabetes Mellitus, Type 1 / blood
  • Diabetes Mellitus, Type 1 / drug therapy*
  • Exercise*
  • Female
  • Humans
  • Hypoglycemia / chemically induced*
  • Hypoglycemic Agents / administration & dosage*
  • Hypoglycemic Agents / adverse effects
  • Hypoglycemic Agents / therapeutic use
  • Insulin / administration & dosage*
  • Insulin / adverse effects
  • Insulin / therapeutic use
  • Insulin Infusion Systems*
  • Male
  • Middle Aged
  • Postprandial Period / drug effects*
  • Young Adult

Substances

  • Blood Glucose
  • Hypoglycemic Agents
  • Insulin