Effect of Diet and Physical Activity on Incidence of Type 2 Diabetes (PREVIEW)
Pre-diabetes, Obesity
About this trial
This is an interventional prevention trial for Pre-diabetes focused on measuring Type-2 diabetes mellitus, Obesity, High protein diet, Low GI, Physical activity
Eligibility Criteria
Inclusion Criteria:
For adults:
Age 25 - 70 years:
From mid 2013 - mid 2014, subjects aged 25-45 and 55-70 years were enrolled. From mid 2014, subjects aged 46-54 years were also enrolled.
- Overweight or obesity status BMI>25 kg/m2
Pre-diabetes The criteria from WHO/IDF (International Diabetes Foundation) for assessing pre-diabetes will be used as the formal inclusion criteria (at screening), i.e. having:
Impaired Fasting Glucose (IFG): Fasting venous plasma glucose concentration 5.6 - 6.9 mmol/l or Impaired Glucose Tolerance (IGT): Venous Plasma glucose concentration of 7.8 - 11.0 mmol/l at 2 h after oral administration of 75 g glucose (oral glucose tolerance test, OGTT), with fasting plasma glucose less than 7.0 mmol/l.
Due to potential between-lab variation (local assessments), HbA1c is not used as an inclusion criteria in the screening.
- Informed consent required
- Ethnic group - No restrictions
- Smoking - Smoking is allowed, provided subjects have not recently (within 1 month) changed habits. However, smoking status is monitored throughout the study and used as a confounding variable.
- Motivation - Motivation and willingness to be randomized to any of the groups and to do his/hers best to follow the given protocol
- Other - Able to participate at CID's during normal working hours.
For children and adolescents:
- Age 10-18 years
- Age-adjusted value corresponding to BMI>25 kg/m2 (Cole et al. 2000)
Since the prevalence of pre-diabetes among children with overweight or obesity is low, it is not feasible to include exclusively pre-diabetic children (according to criteria of the IDF).
Therefore, insulin resistant over-weight/obese children will be included, defined as: HOMA-IR ≥ 2.0 for Tanner stage > 2. No HOMA criteria is used for Tanner stage 1 and 2.
- Informed consent required
- Ethnic group - No restrictions
- Smoking - Smoking is allowed, provided subjects have not recently (within 1 month) changed habits. However, smoking status is monitored throughout the study and used as a confounding variable.
- Motivation - Motivation and willingness to be randomized to any of the groups and to do his/hers best to follow the given protocol
- Other - Able to participate at CID's during normal school/working hours.
Exclusion Criteria:
Based on interview and/or questionnaire, individuals with the following problems will be excluded:
Medical conditions as known by the subjects:
- Diabetes mellitus (other than gestational diabetes mellitus);
- Significant cardiovascular disease including current angina; myocardial infarction or stroke within the past 6 months; heart failure; symptomatic peripheral vascular disease ;
- Systolic blood pressure above 160 mmHg and/or diastolic blood pressure above 100 mmHg whether on or off treatment for hypertension. If being treated, no change in drug treatment within last 3 months;
- Advanced chronic renal impairment;
- Significant liver disease e.g. cirrhosis (fatty liver disease allowed);
- Malignancy which is currently active or in remission for less than five years after last treatment (local basal and squamous cell skin cancer allowed);
- Active inflammatory bowel disease, celiac disease, chronic pancreatitis or other disorder potentially causing malabsorption;
- Previous bariatric surgery;
- Chronic respiratory, neurological, musculoskeletal or other disorders where, in the judgement of the investigator, participants would have unacceptable risk or difficulty in complying with the protocol (e.g. physical activity program);
- A recent surgical procedure until after full convalescence (investigators judgement);
- Transmissible blood-borne diseases e.g. hepatitis B, HIV;
Psychiatric illness (e.g. major depression, bipolar disorder).
Medication:
Use currently or within the previous 3 months of prescription medication that has the potential of affecting body weight or glucose metabolism such as glucocorticoids (but excluding inhaled and topical steroids; bronchodilators are allowed), psychoactive medication, epileptic medication, or weight loss medications (either prescription, over the counter or herbal). Low dose antidepressants are allowed if they, in the judgement of the investigator, do not affect weight or participation to the study protocol. Levothyroxine for treatment of hypothyroidism is allowed if the participant has been on a stable dose for at least 3 months.
Personal/Other:
- Engagement in competitive sports;
- Self-reported weight change of >5 % (increase or decrease) within 2 months prior to screening;
- Special diets (e.g. vegan, Atkins) within 2 months prior to study start. A lacto-vegetarian diet is allowed;
- Severe food intolerance expected to interfere with the study;
- Regularly drinking > 21 alcoholic units/week (men), or > 14 alcoholic units/week (women);
- Use of drugs of abuse within the previous 12 months;
- Blood donation or transfusion within the past 1 month before baseline or CID's;
- Self-reported eating disorders;
- Pregnancy or lactation, including plans to become pregnant within the next 36 months.
- No access to either phone or Internet (this is necessary when being contacted by the instructor's during the maintenance phase);
- Adequate understanding of national language;
Psychological or behavioral problems which, in the judgement of the investigator, would lead to difficulty in complying with the protocol.
Laboratory screening:
If all of the above criteria are satisfied, the participant is eligible for a glucose tolerance test (blood at 0 and 120 mins), and blood glucose concentrations are analyzed immediately (Haemocue). In addition full blood count, urea, and electrolytes may be analyzed as a further safety evaluation. Having normal (i.e. not prediabetic) glucose concentrations at 0 and 2h of OGTT at any stage of the study is not an exclusion criterion.
ONLY IF the glucose tolerance test meets the entry criteria for the study, the remaining samples are sent to the local laboratory for a safety check, with the following exclusion criteria:
- Hemoglobin concentration below local laboratory reference values (i.e. anemia).
- Creatinine >1.5 times Upper Limit of Normal (local laboratory reference values).
- Alanine Transaminase (ALT) and/or Aspartate Transaminase (AST) >3 times the Upper Limit of Normal (local laboratory reference values) Or any other significant abnormality on these tests which in the investigators opinion may be clinically significant and require further assessment
Electrocardiography (ECG). Any abnormality which in the opinion of the investigator might indicate undiagnosed cardiac disease requiring further assessment (e.g. significant conduction disorder, arrhythmia, pathological Q waves). This is done in adults 55-70 years of age.
After LCD phase (in adults):
- Failure to reach at least 8% weight reduction during the LCD phase. This leads to exclusion from the intervention.
Note:
- The listed inclusion and exclusion criteria are applied at screening;
- Having normal (i.e. not pre-diabetic) glucose concentrations at 0 and 2 h of OGTT at any stage of the study after screening is not an exclusion criterion
Sites / Locations
- University of Sydney
- Medical University Sofia
- University of Copenhagen
- University of Helsinki
- University of Maastricht
- University of Auckland
- University of Navarra
- University of Nottingham Medical School
- Swansea University
Arms of the Study
Arm 1
Arm 2
Arm 3
Arm 4
Experimental
Experimental
Experimental
Experimental
HP-HI
HP-MI
MP-HI
MP-MI
High protein/ high intensity physical activity
High protein/ moderate intensity physical activity
Moderate protein/ high intensity physical activity
Moderate protein/ moderate intensity physical activity