Chicago Heart Association Detection Project in Industry

Background/Population:

Jeremiah Stamler is the Principal Investigator on this project begun in 1967 with a screen of 40,000 employees from 100 Chicago firms, about a 55 percent response. It began with a cross-sectional analysis of risk variables and has published 25-year follow-up data of 8,816 middle-aged men and other subgroup analyses.

Methods:

The risk factors included a 1-hour glucose and a standard battery of serum measurements, medical history and habit questionnaires. After cross-sectional relations were studied, the follow-up experience was examined with Cox multivariate proportional hazards regression for relative risk of CVD and other specific causes and total mortality.

Results:

The data have been extensively mined for particular issues of predictability of blood pressure and pulse pressure, for identification of low-risk groups within a U.S. population, for smoking relations at different other risk factor levels, for risk factors for peripheral arterial disease and “distant” mortality and health costs, and for relations of disease and mortality to race and glucose intolerance, resting heart rate, and gender.

Conclusions:

The study is remarkable for its early acquisition of risk factor data in several age, gender and racial groups, for its long follow-up, and for its thoroughgoing and innovative analyses, including pooling with other study data. The data are still being exploited almost 40 years after entry data and by the same institution.

The data have been extensively mined for particular issues of predictability of blood pressure and pulse pressure, for identification of low-risk groups within a U.S. population, for smoking relations at different other risk factor levels, for risk factors for peripheral arterial disease and
“distant” mortality and health costs, and for relations of disease and mortality to race and glucose intolerance, resting heart rate, and gender.

A major contribution has been the study’s systematic analysis of the relationship of overweight to CVD mortality with its elucidation of the effect of methods and design, such as the underestimate of the importance of body mass by adjusting for obesity-related risk factors, by not treating long-term risk (beyond 15 years), or by not adjusting for early mortality. (HB)