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

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