Low cArbohydraTe dIeT and aUtomated Insulin Delivery System for Type 1 DiabetEs — LATITUDE  

Type 1 Diabetes Clinical Trial

Official title: The LATTITUDE Study - Low Carbohydrate Diet and Automated Insulin Delivery System for Type 1 Diabetes

Status Not yet recruiting

Clinical Trial Summary

This is a randomized, controlled study in people living with type 1 diabetes using an automated insulin delivery (AID) system. Participants will be assigned to a control diet (45% carbohydrate) or a low carb diet (25% carbohydrate). The objective is to establish whether the low-carb diet improves time to glycemic targets at 3 months and whether the diet is realistically maintained at 1 year in patients using an AID-DIY system.

Clinical Trial Description

Problems: Despite significant technological and treatment advances for people living with with type 1 diabetes (PWT1D), time in optimal glycemic targets remains difficult to achieve (between 4.0 and 10.0 mmol/L). On the other hand, there is increasing interest in low-carbohydrate diets in the general population (often for weight control), but also in people with diabetes, to help achieve glycemic control (associated with an increase in time in range (TIR).

Automated insulin delivery (AID) systems, including a continuous glucose monitor (CGM) coupled to an insulin pump with an integrated infusion algorithm, increase TIR by approximately 2 hours per day and reduce time in hypoglycemia by 30 minutes, compared to conventional treatments for type 1 diabetes. However, maintaining an optimal TIR remains a significant challenge for PWT1D, despite the increasing use of this technology.

AID systems in combination with a low-carbohydrate diet to optimize TIR have not been studied.

Objectives: To investigate whether low-carb diets improve glucose management and the feasibility of adopting low-carb diets among PWT1D using an AID.

Methods: This is a 12-month prospective, open-label, randomized, controlled study in adults living with type 1 diabetes, with the first 12 weeks as the main study phase and the rest as the extended study phase.

1. Admission period (2-4 weeks): Optimization of insulin doses, validation of carbohydrate calculations and maintenance of usual diet.

2. Main study period (3 months): Study assignment diet (low carbohydrate or usual).

3. Extensive study phase (9 months): Maintenance of assignment diet (if possible) with less frequent visits (observation period).

Hypothesis: The low-carb diet would increase the TIR% (primary outcome) by a mean of 8% (SD 8) compared with the usual diet. Power calculation: Using mean 8% (SD 8), that 38 adults (19 for each group) would provide 80% power at the 5% significance level to detect differences between the two interventions, after considering a 10% drop-out rate.

Full analysis set is defined as participants who have finished recruitment. Per-protocol set is defined as participants who have finished recruitment and have at least 70% of CGM data, at least 70% time in closed-loop mode and at least 4 full days of diet data during week 3-4. The efficiency analysis will be performed using the per-protocol set. The safety analysis will be performed using the full analysis set. ;

Related Conditions & MeSH terms

• Diabetes Mellitus
• Diabetes Mellitus, Type 1
• Type 1 Diabetes

• NCT number: NCT05449678
• Study type: Interventional
• Source: Institut de Recherches Cliniques de Montreal
• Contact: Valérie Boudreau, PhD
• Phone: 514 987-5643
• Email: valerie.boudreau@ircm.qc.ca
• Status: Not yet recruiting
• Phase: N/A
• Start date: September 1, 2022
• Completion date: June 30, 2025