Lifestyle Intervention in a General Population for Prevention of Ischaemic Heart Disease

Study Overview
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Brief Summary
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In spite of declining trend coronary heart disease (CHD) is still a leading cause of morbidity and mortality. Many years of epidemiological research have identified several risk factors for CHD. The main causes are physical inactivity and inappropriate diet (mediated through high blood pressure, high cholesterol and fatness) and smoking. So far intervention studies on lifestyle factors have shown disappointing results, most probably due to insufficient interventions and methodology. Inter99 is a randomized non-pharmacological intervention study comprising 61,301 persons representing a well-defined population. About 13,000 are invited for a health examination and assessment of risk for CHD. Those at high risk are offered lifestyle intervention in three waves over a five year period. A priori the group is divided into a high intensive and low intensive intervention group. The remaining 48.285 individuals serve as control. After five years all individuals who attended the base-line examination are re-invited to assess the effect of the intervention on intermediate end-points as lifestyle, absolute risk of CHD and biological risk factors. The total cohort (61.301) is followed through central registers to evaluate the effect of the intervention on use of the health care system and the long term effect on incidence of CHD. The status for the project is that the four waves of intervention have been performed, the last follow-up was in March 2006. Data collection finalized with 10 years follow-up via Central National Registries and a questionnaire. No further follow-up is scheduled for the main purposes of the study. Analyses as regard the primary effect (on incidence of cardiovascular diseases) and secondary effect (on incidence of type 2 diabetes) are on-going. Analyses for a large number of spin off project are on-going. More than 25 Ph.d. studies and more than 200 peer-review publication have so far been produced. Summary of results, links to articles and theses at: www.Inter99.dk

Detailed Description
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In spite of declining trend coronary heart disease (CHD) is still a leading cause of morbidity and mortality. Many years of epidemiological research have identified several risk factors for CHD. The main causes are physical inactivity and inappropriate diet (mediated through high blood pressure, high cholesterol and fatness) and smoking. So far intervention studies on lifestyle factors have shown disappointing results. Inter99 is a randomized non-pharmacological intervention study comprising 61,301 persons representing a well-defined population. About 13,000 are invited for a health examination and assessment of risk for CHD. Those at high risk are offered lifestyle intervention in three waves over a five year period. A priori the group is divided into a high intensive and low intensive intervention group. The remaining 48.285 individuals serve as control. After five years all individuals who attended the base-line examination are re-invited to assess the effect of the intervention on intermediate end-points as lifestyle, absolute risk of CHD and biological risk factors. The total cohort (61.301) is followed through central registers to evaluate the effect of the intervention on use of the health care system and the long term effect on incidence of CHD.

Official Title
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A Randomised Non-pharmacological Intervention Study for Prevention of Ischaemic Heart Disease Inter99

Conditions
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CHD, AMI, CVD, Type 2 Diabetes, COLD

Intervention / Treatment
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* Behavioral: Lifestyle intervention


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: All citizens in a predefined area Exclusion Criteria: Drug abuse Language problem

Ages Eligible for Study
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Minimum Age: 30 Years
Maximum Age: 60 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

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: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: High intensity intervention group<br>Lifestyle intervention consisted of 15-30 minutes of individual lifestyle counselling + offer of participation in group-based lifestyle counselling (½ year). This offer was given at baseline to all participants in the group. Persons at high risk of IHD: offer additionally given at 1- and 3-year follow-up | Behavioral: Lifestyle intervention<br> <br> |
| Experimental: Low intensity intervention group<br>Lifestyle intervention consisted of 15-30 minutes of individual lifestyle counselling. This offer was given at baseline to all participants in the group. Persons at high risk of IHD: offer additionally given at 1- and 3-year follow-up | Behavioral: Lifestyle intervention<br> <br> |
| No Intervention: Control group<br>Questionnaires regarding lifestyle and general health were sent to all participants in this group. The importance of healthy lifestyle was not mentioned, and no intervention was offered. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of CHD and other lifestyle related diseases after ten years | Ongoing analyses in National Central Registers (Oct 2012) | 2012 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in lifestyle and biological markers after one, three and five years | Analyses completed. Results at: www.Inter99.dk | 2006 | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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CHD, Lifestyle intervention, Behavioural changes, Type 2 diabetes