Manchester Intermittent and Daily diet Type 1 Diabetes App Study (MIDDAS-Type 1): protocol for a randomised feasibility trial of an intermittent and continuous low-energy diet in patients with type 1 diabetes and overweight and obesity.

INTRODUCTION: Rising levels of overweight and obesity among people with type 1 diabetes (T1D) contribute to insulin resistance, dyslipidaemia, retinopathy, cardiometabolic complications and psychological morbidity. Continuous low-energy diets (CLED) providing approximately 800 kcal (3347 kJ)/day can produce significant weight loss in type 2 diabetes, and intermittent low-energy diets (ILED) may be an alternative. The Manchester Intermittent and Daily diet Type 1 Diabetes App Study (MIDDAS-Type 1) aims to assess the safety, acceptability and feasibility of remotely delivered ILED and CLED programmes for people with T1D and overweight and obesity. METHODS AND ANALYSIS: Twelve participants with T1D and body mass index ≥27.5 kg/m2 (≥25 kg/m2 in high-risk ethnic minorities) recruited from an National Health Service (NHS) trust and research register in England will be randomised to a remotely delivered CLED (n=6) or ILED (n=6) for 12 weeks. The CLED includes a daily Optifast 850 kcal (3556 kJ) 75 g carbohydrate formula diet. The ILED includes 2 days/week of Optifast and 5 days of a portion-controlled Mediterranean diet (170-250 g carbohydrate/day). Both groups will receive matched high-frequency remote support from a dietitian, nurse and psychologist via telephone and/or the Oviva app. The primary outcome will assess safety (occurrence of severe hypoglycaemia, ketonaemia, ketoacidosis and time above and below target blood glucose). Secondary outcomes include study uptake, retention, dietary adherence, acceptability, intervention delivery fidelity and potential efficacy in relation to change in weight, insulin requirements, glycated haemoglobin, lipids, insulin resistance (estimated glucose disposal rate) and quality of life. Participants will be invited for optional repeat measurements at 52 weeks. ETHICS AND DISSEMINATION: The trial protocol (V4.0/08.06.2022) was granted ethical approval by Cambridge East Research Ethics Committee (Ref: 21/EE/0014). The study will inform progression to a full-scale randomised controlled trial to test the efficacy of these programmes for patients with T1D and overweight and obesity. TRIAL REGISTRATION NUMBER: NCT04674384; Pre-results.

Manchester Intermittent versus Daily Diet App Study (MIDDAS): A pilot randomized controlled trial in patients with type 2 diabetes.

AIMS: To test the feasibility and potential efficacy of remotely supported intermittent low-energy diets (ILEDs) and continuous low-energy diets (CLEDs) in people with type 2 diabetes (T2D) and the feasibility of a randomized controlled trial comparing the two approaches. MATERIALS AND METHODS: Seventy-nine adults with overweight/obesity and T2D (≤8 years duration) were randomized 1:1 to CLED (8 weeks/56 days of daily Optifast 820 kcal (3430 kJ) diet) or isoenergetic ILED (2 days of Optifast and 5 days of a Mediterranean diet/week for 28 weeks). Weight maintenance/continued weight loss was undertaken for the remainder of the 52 weeks. Both groups received frequent telephone or the Oviva app support. Feasibility outcomes included study uptake, retention, app usage, dietary adherence, weight loss and change in glycated haemoglobin (HbA1c) at 52 weeks. RESULTS: We enrolled 39 ILED and 40 CLED participants and 27 (69%) ILED and 30 CLED (75%) attended the 52-week follow-up. Eighty-nine per cent (70 of 79) started using the app and 86% (44 of 51) still used the app at 52 weeks. Intention-to-treat analysis at 52 weeks showed percentage weight loss was mean (95% confidence interval) -5.4% (-7.6, -3.1%) for ILED and -6.0% (-7.9, -4.0%) for CLED. HbA1c <48 mmol/mol was achieved in 42% of both groups. Mean (95% confidence interval) changes in the T2D medication effect score were 0.0008 (-0.3, 0.3) for ILED and -0.5 (-0.8, -0.3) for CLED. CONCLUSION: The study shows the feasibility and potential efficacy of remotely delivered ILED and CLED programmes for weight loss and HbA1c reduction, and the feasibility of a randomized controlled trial comparing the two approaches.

Intermittent Versus Continuous Low-Energy Diet in Patients With Type 2 Diabetes: Protocol for a Pilot Randomized Controlled Trial.

BACKGROUND: Intensive face-to-face weight loss programs using continuous low-energy diets (CLEDs) providing approximately 800 kcal per day (3347 kJ per day) can produce significant weight loss and remission from type 2 diabetes (T2D). Intermittent low-energy diets (ILEDs) and remotely delivered programs could be viable alternatives that may support patient choice and adherence. OBJECTIVE: This paper describes the protocol of a pilot randomized controlled trial to test the feasibility and potential efficacy of remotely supported isocaloric ILED and CLED programs among patients with overweight and obesity and T2D. METHODS: A total of 79 participants were recruited from primary care, two National Health Service hospital trusts, and a voluntary T2D research register in the United Kingdom. The participants were randomized to a remotely delivered ILED (n=39) or CLED (n=40). The active weight loss phase of CLED involved 8 weeks of Optifast 820 kcal/3430 kJ formula diet, followed by 4 weeks of food reintroduction. The active weight loss phase of ILED (n=39) comprised 2 days of Optifast 820 kcal/3430 kJ diet and 5 days of a portion-controlled Mediterranean diet for 28 weeks. Both groups were asked to complete 56 Optifast 820 kcal/3430 kJ days during their active weight loss phase with an equivalent energy deficit. The diets were isocaloric for the remainder of the 12 months. CLED participants were asked to follow a portion-controlled Mediterranean diet 7 days per week. ILED followed 1-2 days per week of a food-based 820 kcal/3430 kJ diet and a portion-controlled Mediterranean diet for 5-6 days per week. Participants received high-frequency (weekly, fortnightly, or monthly depending on the stage of the trial) multidisciplinary remote support from a dietitian, nurse, exercise specialist, and psychologist via telephone or the Oviva smartphone app. The primary outcomes of the study were uptake, weight loss, and changes in glycated hemoglobin at 12 months. An outcome assessment of trial retention was retrospectively added. Secondary outcomes included an assessment of adherence and adverse events. A qualitative evaluation was undertaken via interviews with participants and health care professionals who delivered the intervention. RESULTS: A total of 79 overweight or obese participants aged 18-75 years and diagnosed with T2D in the last 8 years were recruited to the Manchester Intermittent and Daily Diet Diabetes App Study (MIDDAS). Recruitment began in February 2018, and data collection was completed in February 2020. Data analysis began in June 2020, and the first results are expected to be submitted for publication in 2021. CONCLUSIONS: The outcomes of the MIDDAS study will inform the feasibility of remotely delivered ILED and CLED programs in clinical practice and the requirement for a larger-scale randomized controlled trial. TRIAL REGISTRATION: International Standard Randomized Controlled Trial Number (ISRCTN) 15394285; http://www.isrctn.com/ISRCTN15394285. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/21116.