Cohort Profile: The STRIP Study (Special Turku Coronary Risk Factor Intervention Project), an Infancy-onset Dietary and Life-style Intervention Trial

Abstract

It is now clear that atherosclerosis develops as a result of a life-long process often leading to coronary heart disease. Nutritional recommendations have been delivered to the general community to manage this epidemic. Since fat is an important source of energy and cholesterol is required for sex hormone synthesis, fears have emerged that low intake of saturated fat and cholesterol might influence children’s growth and development. Infants and young children have therefore been excluded from these nutritional recommendations. However, a number of arguments support the concept that prevention of children’s exposure to atherosclerosis risk factors should be started at an early age. Dietary fat intake and quality of fat regulate serum lipoprotein values in childhood in the same way as they do in adults. It has also been shown that children with high serum cholesterol and LDL cholesterol values are predisposed to early atherosclerotic changes in aorta and large arteries and high LDL cholesterol values in childhood associate with increased atherosclerotic changes in carotid arteries measured decades later. All these changes can be influenced by living habits. A lifestyle with emphasis on avoiding atherosclerosis risk factors might be most easily adopted if introduced in early childhood. A large cross-sectional coronary risk factor follow-up study, the Cardiovascular Risk in Young Finns (CRYF) has continued in Finland since 1980. In that study, an extensive number of atherosclerosis risk factors have been studied repeatedly in an initial cohort of 3596 individuals from age 3 years onwards. CRYF is a follow-up study without intervention, and a need for an interventional approach to control the coronary risk factors in childhood was evident. Finland is an ideal location to perform an atherosclerosis risk factor intervention study, since serum cholesterol values of Finnish boys have been high in international comparisons and, at the same time, coronary artery disease incidence in Finnish adults has also been very high. Moreover, the participation rate has by tradition been high in Finnish epidemiological trials. Due to these reasons, grant-funded Special Turku Coronary Risk Factor Intervention Project (STRIP) study was launched in 1989 to study whether it is possible to reduce exposure to coronary risk factors effectively and safely from early age on.