(Cost-)Effectiveness of SLIMMER Diabetes Prevention Intervention

Study Overview
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Brief Summary
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The overall aim of the project is to evaluate the (cost-)effectiveness of the SLIMMER diabetes prevention intervention in Dutch primary health care.

Detailed Description
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This is a randomised controlled trial, conducted in a real-life setting (Dutch primary health care).

Official Title
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Implementation and (Cost-)Effectiveness of Diabetes Prevention in Dutch Primary Health Care: From SLIM to SLIMMER

Conditions
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Diabetes Mellitus Type 2

Intervention / Treatment
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* Behavioral: Combined lifestyle intervention
* Other: Usual care group


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 40-70 years Impaired fasting glucose (IFG; i.e. venous plasma glucose concentration ≥6.1 and ≤6.9 mmol/l) during the past 5 years, according to the GP registration database OR diabetes risk score ≥7 as calculated from the Diabetes Risk Test Willing and able to participate in the intervention for at least 1.5 years Dutch speaking Exclusion Criteria: Known diabetes mellitus Any chronic illness that makes 1.5-years survival improbable, interferes with glucose tolerance, or makes participation in a lifestyle intervention impossible Patients with any severe cardiovascular disease (this also includes history of cardiac dysrhythmia), unless GP gives agreement Medication known to interfere with glucose tolerance Any mental or physical disability that will hinder participation in the lifestyle intervention Severe psychiatric disease Patients who showed bad compliance in the past Participation in another regular vigorous exercise and/or diet programme, i.e.: Intensive exercise programme: any exercise programme offered by a physiotherapist and/or patients sporting at least 3 times a week at their own initiative. Intensive diet programme: patients who visited a dietician at least 3 times during the last year.

Ages Eligible for Study
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Minimum Age: 40 Years
Maximum Age: 70 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Combined lifestyle intervention<br>Lifestyle counselling (nutrition and physical activity) by dietician and physiotherapist during 10-month intervention period | Behavioral: Combined lifestyle intervention<br>* 10-month intervention period with: weekly group-based sports lessons supervised by a physiotherapist individual dietary advice by a dietician case management by practice nurse maintenance programme to guide subjects to maintain lifestyle behaviour change<br>* Other names: SLIMMER intervention;|
| Other: Usual care group<br>Subjects receive brochures on healthy lifestyle at baseline, and during the 10-month intervention period only usual care as provided by their own general practitioner. | Other: Usual care group<br>* Written information on healthy lifestyle was provided at baseline, no individual advice or programme was provided. No additional appointments were scheduled, apart from the visits for follow-up measurements<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in fasting insulin |  | Baseline, end of intervention (12 months), after follow-up (18 months) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Glucose tolerance | fasting glucose, 2h glucose, 2h insulin, HbA1c | Baseline, end of intervention (12 months), after follow-up (18 months) | 
| Serum lipids | total cholesterol, HDL cholesterol, LDL cholesterol, triglycerides | Baseline, end of intervention (12 months), after follow-up (18 months) | 
| Body fatness | body weight, BMI, waist and hip circumference, body fat | Baseline, end of intervention (12 months), after follow-up (18 months) | 
| Physical fitness | measured with six-minute walk test | Baseline, end of intervention (12 months), after follow-up (18 months) | 
| Blood pressure |  | Baseline, end of intervention (12 months), after follow-up (18 months) | 
| Medication use |  | Baseline, end of intervention (12 months), after follow-up (18 months) | 
| Quality of Life |  | Baseline, end of intervention (12 months), after follow-up (18 months) | 
| Eating behaviour | Measured as nutrient intake and food intake, with a Food Frequency Questionnaire | Baseline, end of intervention (12 months), after follow-up (18 months) | 
| Physical activity behaviour | Measured with questionnaire | Baseline, end of intervention (12 months), after follow-up (18 months) | 
| Behavioural determinants | Determinants of nutrition and physical activity behaviour, measured with questionnaire | Baseline, end of intervention (12 months), after follow-up (18 months) | 
| Process indicators | Indicators to investigate how the intervention was delivered and received, measured with quantitative and qualitative methods | Baseline, end of intervention (12 months), after follow-up (18 months) | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Prevention, Combined lifestyle intervention, Primary health care