The Norwegian trial of Physical Exercise After Myocardial Infarction - NorEx -

Regular physical activity is recommended both to prevent cardiovascular disease in healthy persons and to prevent recurrence or worsening in people already affected by such diseases. However, the scientific evidence for these recommendations is weak, and in reality, we do not know whether previously untrained people have permanent health benefits from starting physical exercise. We will conduct a large intervention trial with a sound scientific design that to examine whether physical activity improves life expectancy, reduces the risk of heart disease, and enhance quality of life among people who have had a heart attack. The study will last for 4 years and will include 9 700 patients. Participants are randomly allocated to a group that will receive supervised physical training throughout the study period or to two control groups that are given usual advice on physical activity. The hypothesis is that supervised physical exercise leads to a 20% reduction in mortality and major cardiovascular disease. In addition, we will examine whether physical exercise affects the risk cancer, mental health, and quality of life. The study has a design that utilizes Norwegian health registers and other unique Norwegian comparative advantages and is led by a research group with longtime experience in studies of physical activity and large randomized multi-center studies. The study is the largest trial ever conducted in this field, and the first study with a potential to find out whether physical activity affects life expectancy and quality of life, and to determine how large such effects may be. The study will provide a clear answer to a question that is of major importance both in clinical medicine as well as for public health. The study findings may have implications for medical practice. A total of 7657 patients are included in the NorEx trial as of November 23. 2023. Base on current inclusion rates, we expect that a total of 9 700 will be included by July 2024. All patients will be followed up for at least 3 years. The final results will be reported in 2028. We have also planned to follow up all participants at least 10 years after inclusion.

Myocardial infarction (MI) remain the main cause of death in Europe, and is one of the greatest medical and scientific challenges of our generation. According to WHO, 30% of deaths caused by MI could be prevented if the populations adhere to official guidelines for physical activity (PA). However, these estimates are based on epidemiological data and no randomized controlled trial has shown that PA reduces the risk of MI. NorEx is a large Norwegian registry-based multicenter and multiregional RCT for secondary prevention and rehabilitation of patients who have suffered an MI, using PA as the method of intervention. We hypothesize that supervised moderate to vigorous PA will lower mortality and cardiovascular disease morbidity by 15 % compared to standard care. To provide sufficient statistical power and robust causative evidence on the long-term effects of PA, we will randomize a total of 12750 MI patients to either 3.5 years of supervised PA (n=4250) or standard care (n=8500). NorEx’s interdisciplinary research program utilizes major Norwegian advantages, including each inhabitant’s unique personal identification number that enables follow-up of the participants’ health outcomes in a number of mandatory and high-quality national health registries. NorEx takes advantage of a novel study design to minimize the effects of non-adherence to the prescribed exercise levels in the intervention group, and to minimize the effects of crossover to increased exercise intensity the control group. NorEx is the first large RCT to fully realize the research potential of Norwegian health registries both for the recruitment of a representative study population and for complete and unbiased follow-up of all study participants for hard clinical end-points. NorEx will be the first trial with sufficient statistical power to resolve an important clinical question and provide novel data to an area that is currently lacking high quality data on cause and effect.