What Or When to Eat to Reduce the Risk of Type 2 Diabetes (WOW)

A parallel, single-blinded, multi-centre randomized controlled trial conducted at the South Australian Health and Medical Research Institute (SAHMRI) and the Mary Mackillop Institute for Health Research (MMIHR; Australian Catholic University), by researchers from the University of Adelaide, Australian Catholic University and La Trobe University.

Study Overview

• Status: Recruiting
• Conditions: Diet Quality; Time-restricted Eating
• Intervention / Treatment: Other: Time-restricted eating; Other: Current Best Practice

Detailed Description

In a parallel groups design, a total of 268 individuals will be recruited across both sites. After a 2-week baseline period, and a baseline metabolic visit, participants will be randomized into one of two groups (TRE, time-restricted eating; CP, current practice guidelines). All participants will receive five (5) telehealth consultations at baseline, week 2, 4, 8 and 12, the content of which will be based around their randomized condition. They will undergo metabolic testing on two (2) further occasions (4 months, 12 months) over a 12-month period to assess the changes in primary and secondary outcomes.

• Study Type: Interventional
• Enrollment (Anticipated): 268
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Amy Hutchison, PhD; Phone Number: 08 8128 4862; Email: amy.hutchison@adelaide.edu.au
• Study Contact Backup: Name: Evelyn Parr, PhD; Phone Number: 03 9230 8278; Email: evelyn.parr@acu.edu.au

Study Locations

• Australia
  • South Australia
    • Adelaide, South Australia, Australia
      • Recruiting
      • South Australian Health and Medical Research Institute
      • Contact: Amy Hutchison, PhD; Phone Number: 08 8128 4862; Email: amy.hutchison@adelaide.edu.au
  • Victoria
    • Melbourne, Victoria, Australia
      • Recruiting
      • Mary Mackillop Institute for Health Research
      • Contact: Evelyn Parr, PhD; Phone Number: 03 9230 8278; Email: evelyn.parr@acu.edu.au

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 35 years to 70 years (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Study participants will be aged 35 to 70 years, overweight or obese (BMI: >25 but <45 kg/m2), ≥15 on the AUSDRISK assessment tool and have HbA1c <6.5% at screening

Exclusion Criteria:

• A personal history/diagnosis (self-reported) of:

  • diabetes (type 1 or 2)
  • major psychiatric disorders (schizophrenia, major depressive disorder, bipolar disorder, eating disorders)
  • gastrointestinal disorders/disease (including malabsorption)
  • haematological disorders (i.e. thalassemia, iron-deficiency anaemia)
  • insomnia
  • currently receiving, or have received treatment/diagnosis of cancer in the past 3 years (excluding non-melanoma skin cancer)
  • significant liver or kidney disease
  • previous or planned gastro-intestinal surgery (including bariatric surgery)
  • Congestive heart failure (NYHA stage 2 or above)
  • Previous myocardial infarction or significant cardiac event ≤ 6 months prior to screening
  • Previous cerebrovascular event ≤ 12 months prior to screening

and/or any other condition deemed unstable by the study physician.

Currently taking the following medications:

• any medication used, or known to lower blood glucose, or antidiabetic medications, including, but not limited to: SGLT2 inhibitors, metformin, sulfonylureas, glucagon-like peptide-1 (GLP-1) analogues [i.e. exenatide], thiazolidinediones or DPP-IV inhibitors [i.e. 'gliptins'])
• Medications affecting weight, appetite or gut motility, including, but not limited to: (domperidone, cisapride, orlistat, phentermine, topiramate).
• Diuretics (i.e. frusemide, thiazides) or combination blood pressure medications containing a diuretic
• Beta-blockers
• Glucocorticoids
• Anti-epileptic medications
• Antipsychotic medications
• Opioid medications unless combined with paracetamol in a single formulation and used occasionally on a PRN basis

Additional exclusion criteria include:

• do not consume a regular breakfast (i.e. eat breakfast on an average of 5 or more days per week), OR do not eat for more than 12 hours per day on an average of 5 or more days per week
• have an extreme or restricted pattern of eating (i.e. following an intermittent fasting diet) or are already engaged in a TRE protocol
• shift-workers
• pregnant, planning a pregnancy or currently breastfeeding
• those who have lost or gained >5% of body weight in the last 6 months
• current smokers of cigarettes/marijuana/e-cigarettes/vaporisers
• anyone unable to comprehend the study protocol or provide informed consent (i.e. due to English language or cognitive difficulties)
• Participants will not have seen a dietitian in the preceding 3 months.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Time-restricted eating (TRE); The TRE group will be instructed to follow TRE (9 h/day) every day for 12 months with no other dietary instructions or advice provided. The TRE group will attend the same consult schedule as the CP group, but consultations will focus on timing of dietary intake and strategies to promote adherence. No dietary guidance regarding quantity or quality will be provided. Participants will be able to self-select the precise 9-h schedule that will best suit their lifestyles, with the caveat that the latest time of eating will be set at 7:00 pm. Outside of the elected eating window, participants will be allowed to consume water and black coffee and/or tea.	Other: Time-restricted eating; Time restricted eating for a self-selected 9 hour window per day
Active Comparator: Current Best Practice (CP); This group is designed to act as a comparator using 'standard care' in dietetics practice. Dietary advice provided to this participant group will be performed by Accredited Practicing Dietitians (APDs) in line with evidence-based guidelines, specifically the T2DM best-practice guidelines plus Australian Dietary Guidelines (i.e. Australian Guide to Healthy Eating) to improve diet quality, and strategies to promote adherence. No specific advice will be provided regarding time of day to start and finish eating and/or drinking (since this information is not outlined in current practice guidelines).	Other: Current Best Practice; Best practice guidelines to improve diet quality

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
HbA1c	Glycated haemoglobin concentration	4 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
HbA1c	Glycated haemoglobin concentration	12 months
24-hour glucose variability	Assessment of 24 hour glucose variability by continuous glucose monitor	4 months
Body weight	change in body weight	4 months, 12 months
Waist circumference	change in waist circumference	4 months, 12 months
Hip circumference	change in hip circumference	4 months, 12 months
Fasting blood glucose	Change in fasting blood glucose concentrations	4 months, 12 months
Fasting insulin	Change in fasting insulin concentrations	4 months, 12 months
Blood lipids	Change in total, HDL and LDL cholesterol and triglycerides	4 months, 12 months
Physical activity	Changes in activity assessed by inclinometer	4 months, 12 months
Body composition	change in percent body fat, fat free mass by DXA	4 months, 12 months
Adherence	measures of adherence assessed by self-report	0.5, 1, 2, 3, 4, 8, 12 months

Collaborators and Investigators

• Sponsor: University of Adelaide
• Collaborators: Australian Catholic University; La Trobe University
• Investigators: Principal Investigator: John Hawley, PhD, Australian Catholic University

Study record dates

Study Major Dates

• Study Start (Actual): February 17, 2021
• Primary Completion (Anticipated): July 11, 2023
• Study Completion (Anticipated): January 11, 2025

Study Registration Dates

• First Submitted: February 16, 2021
• First Submitted That Met QC Criteria: February 16, 2021
• First Posted (Actual): February 21, 2021

Study Record Updates

• Last Update Posted (Actual): March 27, 2023
• Last Update Submitted That Met QC Criteria: March 23, 2023
• Last Verified: March 1, 2023

More Information

Terms related to this study

• Other Study ID Numbers: 14023 (Other Identifier: City of Hope Medical Center)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: The data that support the findings of this study will be available from the corresponding author for a period of 36 months from publication, upon reasonable request for academic use. The data will not be made publically available, as it contains information that could compromise research participant consent.
• IPD Sharing Time Frame: 36 months from date of publication
• IPD Sharing Access Criteria: Reasonable requests of data for academic use will be considered. Requests can be made to the corresponding author of the publication. Data will not be made publically available as it contains information that could compromise research participant consent.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No