title: Glycaemic load versus carbohydrate counting for insulin bolus calculation in patients with type 1 diabetes on insulin pump.
abstract: OBJECTIVE
  To evaluate feasibility and effectiveness on short-term blood glucose control of using glycaemic load counting (GLC) versus carbohydrate counting (CC) for prandial insulin dosing in patients with type 1 diabetes (T1D).
  
  
  METHODS
  Nine T1D patients on insulin pump, aged 26-58 years, HbA1c 7.7 ± 0.8 % (61 ± 8.7 mmol/mol), participated in this real-life setting study. By a crossover design, patients were randomised to calculate their pre-meal insulin dose based on the insulin/glycaemic load ratio (GLC period) or the insulin/carbohydrate ratio (CC period) for 1 week, shifting to the alternate method for the next week, when participants duplicated their first week food plan. Over either week, a blind subcutaneous continuous glucose monitoring was performed, and a 7-day food record was filled in.
  
  
  RESULTS
  Total daily insulin doses (45 ± 10 vs. 44 ± 9 I.U.; M ± SD, p = 0.386) and basal infusion (26 ± 7 vs. 26 ± 8 I.U., p = 0.516) were not different during GLC and CC periods, respectively. However, the range of insulin doses (difference between highest and lowest insulin dose) was wider during GLC, with statistical significance at dinner (8.4 ± 6.2 vs. 6.0 ± 3.9 I.U., p = 0.041). Blood glucose iAUC after lunch was lower, albeit not significantly, during GLC than CC period (0.6 ± 8.6 vs. 3.4 ± 8.2 mmol/l∙3 h, p = 0.059). Postprandial glucose variability, evaluated as the maximal amplitude after meal (highest minus lowest glucose value), was significantly lower during GLC than CC period at lunch (4.22 ± 0.28 vs. 5.47 ± 0.39 mmol/l, p = 0.002) and dinner (3.89 ± 0.33 vs. 4.89 ± 0.33, p = 0.026).
  
  
  CONCLUSIONS
  Calculating prandial insulin bolus based on glycaemic load counting is feasible in a real-life setting and may improve postprandial glucose control in people with T1D.
authors.affiliation: Department of Clinical Medicine and Surgery, Federico II University, Via Pansini, 5, 80131, Naples, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Bozzetto
authors.affiliation: Department of Clinical Medicine and Surgery, Federico II University, Via Pansini, 5, 80131, Naples, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Giorgini
authors.affiliation: Department of Clinical Medicine and Surgery, Federico II University, Via Pansini, 5, 80131, Naples, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Alderisio
authors.affiliation: Department of Clinical Medicine and Surgery, Federico II University, Via Pansini, 5, 80131, Naples, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Costagliola
authors.affiliation: Department of Clinical Medicine and Surgery, Federico II University, Via Pansini, 5, 80131, Naples, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Giacco
authors.affiliation: Department of Clinical Medicine and Surgery, Federico II University, Via Pansini, 5, 80131, Naples, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Riccardi
authors.affiliation: Department of Clinical Medicine and Surgery, Federico II University, Via Pansini, 5, 80131, Naples, Italy. rivelles@unina.it.
authors.forename: A A
authors.initials: AA
authors.lastname: Rivellese
authors.affiliation: Department of Clinical Medicine and Surgery, Federico II University, Via Pansini, 5, 80131, Naples, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Annuzzi
mesh_terms: D000328:Adult; D001786:Blood Glucose / Q000032:analysis; D018592:Cross-Over Studies; D003922:Diabetes Mellitus, Type 1 / Q000097:blood / Q000188:drug therapy*; D004040:Dietary Carbohydrates / Q000032:analysis*; D005260:Female; D005947:Glucose; D006442:Glycated Hemoglobin / Q000032:analysis; D000067940:Glycemic Load; D006801:Humans; D007003:Hypoglycemia / Q000453:epidemiology; D007328:Insulin / Q000008:administration & dosage*; D007332:Insulin Infusion Systems; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D019518:Postprandial Period
chemical_list: D001786:Blood Glucose; D004040:Dietary Carbohydrates; D005947:Glucose; D006442:Glycated Hemoglobin; D007328:Insulin
keywords: Carbohydrate counting; Continuous subcutaneous glucose monitoring; Glycaemic load; Prandial insulin; Type 1 diabetes