Multifactorial primary prevention trials of coronary heart disease

The hypotheses of reversibility of risk and of prevention of increasing risk represent the theoretical basis for any attempt to prevent coronary heart disease. After the impressive but inconclusive trials of the first generation, conducted principally in the sixties and on single risk factors, the second-generation trials, begun in the seventies and focused mainly on multifactor intervention, are now producing preliminary results. Although many problems remain unresolved and many questions are as yet unanswered, several results indicate the feasibility of mass intervention aimed at changing the risk-factor levels and suggest an association of such action with a measurable reduction in the incidence of coronary heart disease.