The National Cooperative Trial on Multifactorial Prevention of First Heart Attacks and Coronary Mortality in Free-Living, High-Risk, Middle-Aged American Men, Also Known as JUMBO: A Short Story

Early Contributions to the Design and Conduct of Clinical Trials From a Largely Unknown 1960s Pilot Trial of Physical Activity and a Well-Known Diet-Heart Feasibility Study for the Primary Prevention of Coronary Heart Disease

This historical note focuses on contributions to the concepts, design, methods, and conduct of clinical trials from the 1960s planning and findings of a feasibility study that was little reported and largely unrecognized: the Pilot Study of Prescribed Physical Activity for the Primary Prevention of Ischemic Heart Disease (1963-1968). In contrast, complementary findings from the 1960s National Diet-Heart Feasibility Study (1962-1968) were fully reported, widely recognized, and well-analyzed by historians in context of the rapid evolution in chronic disease epidemiology and clinical trials following World War II. The experience of these thoughtfully planned and rigorously conducted pilot studies changed the career paths of their planners and investigators and shaped the form and direction of subsequent research on the causes, treatment, and prevention of heart attack. The 2 studies were both fruit and seed of a consortium of experts that evolved in reaction to new questions and findings about the midcentury coronary disease epidemic. The contributions of each study, and of this broader academy of pioneer thinkers, are essential elements in the history of cardiovascular disease epidemiology, prevention research, and health policy.

The North Karelia Project (1972-1997) and the Origins of the Community Approach to Cardiovascular Disease Prevention

Community-based risk factor modification is today an established approach to chronic disease control and public health practice. This article analyzes the shaping of the North Karelia Project (NKP), an early and influential formulation of the community approach that focused on coronary heart disease prevention in Finland. Instead of targeting only high-risk individuals, NKP aimed to change the culture of the local community. On the basis of archival material and interviews, I first trace the multiple origins of the notion of community in NKP, which combined "internal" factors (local risk factor distribution, the role given to the social environment in chronic disease prevention) and "external" influences (regional origin of the initiative, World Health Organization and national policy concepts of community control and primary health care). Second, I describe the shape of the community intervention in NKP. The project foregrounded social relationships as a way to educate the public and influence norms guiding individual behaviors while subordinating environmental changes of a more structural nature.

Invited Commentary: Learning From Our Past to Build on Our Future- Lessons Learned From MRFIT and JUMBO

We propose that Blackburn (Am J Epidemiol. 2020;189(6):491-498) ignores several important issues that need to be considered in the context of a historical reflection of the National Heart Institute's landmark study, the Multiple Risk Factor Intervention Trial (MRFIT), and the alternative proposal, the "JUMBO" trial, submitted to the National Heart Institute by an experienced team of extramural investigators but never funded. A key focus of this commentary is to offer an alternative perspective on both studies using our current understanding of the impact of social and structural determinants of health; evidence that policy, systems, and environmental interventions are needed to support behavior change at the individual level; and the significance of examining research from a racial/socioeconomic equity lens. While we strongly agree with Blackburn's conclusion urging the National Institutes of Health to invest in prevention research at a level consistent with its social and economic impact, we encourage the author to move beyond simply underscoring the methodological limitations and failure of the findings of MRFIT compared with the potential of the proposed JUMBO trial to consider the contribution of MRFIT to our current understanding of chronic disease prevention and treatment.

Invited Commentary: Can You Do Trials of Behavioral Modification, Such as Diet or Exercise Intervention, With Hard Endpoints?

Blackburn (Am J Epidemiol. 2020;189(6):491-498) describes the evolution from the Makarska Conference in 1968 to the planning of the JUMBO trial and the decision by the National Institutes of Health (NIH) to do the Multiple Risk Factor Intervention Trial. He attributes the failure of the Multiple Risk Factor Intervention Trial to show a significant reduction in coronary heart disease or total mortality to the design of the trial, the multiple centers involved, and continued bureaucracy. The paper is important in raising 3 issues of continued relevance: 1) What is the relationship of the NIH staff in both development and monitoring of large cooperative studies, especially clinical trials, outside of the walls of the NIH? 2) Can clinical trials that utilize individual randomization to intervention and comparison be successful in evaluating a common-source epidemic, such as diet and coronary heart disease, especially in populations with readily available foods and competing advertising, etc.? 3) How much information obtained from, e.g., observational studies, animal models, and genetic studies, is necessary given limits of human population clinical trials of behavioral intervention to develop recommendations for strong public health programs to reduce morbidity and mortality, and what is the measure of successful intervention?