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Completion of cardiovascular evaluations of 387 members marked the end of 40 years of follow-up in the West Point Study. Coronary artery disease (CAD) caused 4 cases of sudden death, 14 cases of myocardial infarction (MI), 13 cases of angina, and 17 cases of silent CAD. Using risk factors (serum cholesterol, estimated HDL-cholesterol, systolic blood pressure, and smoking status) measured before age 28, we derived a multivariate regression formula for predicting which members of the study, had they been pilots, would have been grounded for CAD before age 55. This derivation used data from only those subjects with CAD or with no evidence of CAD. We then used the formula to compute a risk-related score for each member of the study. In the tertile group with the highest risk-related scores, 17% manifested CAD by age 55 and the first event occurred at age 39. In the tertile group of lowest scores, 2% experienced CAD by age 55 and the first event occurred at age 51. We conclude that it is possible to select pilot candidates with the lowest risk for CAD.

During a 1-year period, the United States Air Force School of Aerospace Medicine reviewed routine exercise tests by 771 completely asymptomatic male flying personnel aged 35-54 years, who underwent the stress test as the sole screening procedure to detect latent coronary artery disease. All of the aviators had a normal baseline 12-lead electrocardiogram, which would not have required a stress test in accordance with current policies of the USAF Central Electrocardiographic Library. Of these 771 exercise tests, 153 were maximal treadmill tests without a previous Double Master's Step test, and 618 were Double Master's tests. Borderline abnormal or abnormal Double Master's tests were followed by treadmill testing. Airmen with abnormal treadmill tests were offered coronary angiography for clarification of the aeromedical significance of the test result. The predictive value of a routine abnormal treadmill test in a population of aircrew members with a borderline abnormal or abnormal Double Master's test ranged from 17-55%. Thus, mass screening for coronary artery disease with exercise stress tests in apparently asymptomatic individuals is hampered by a low yield of true positive test in an unacceptably high proportion of false positive results.

The new generation of high-performance aircraft has clearly emphasized man's physiological limitations to withstand sustained high G loading. The selection and retention standards required to function in this environment have not been completely defined. The authors will offer a format of standards and screening tests, placing special emphasis on the detection of subclinical disease, particularly coronary artery disease. Cases which illustrate the spectrum of asymptomatic coronary disease will be presented. Other entities discussed will include conduction defects, mild valvular lesions, arrhythmias, and degenerative joint disease of the spine. An overall approach based on age, screening milestones, and specialized tests will be presented. Finally, a data repository on all pilots with chronic high G exposure will be discussed.

This report reviews the current status of the West Point Study and addresses the prediction of risk of coronary artery disease (CAD) based on cholesterol levels measured at various times during the study. Subjects were grouped into quintiles by their risk index score calculated from the Framingham risk equation. The number of cases of CAD among the subjects in each of the quintiles was tabulated. The cases of CAD in these quintiles increased from the lowest to the highest quintiles and produced a significant correlation between the risk score and the percent of subjects in the quintiles having CAD, even when the data used for calculating the risk scores had been collected up to 26 years earlier. The numbers of CAD cases are small; they are only approximately 50% of the expected numbers computed for U.S. males of comparable ages, despite the increases in serum cholesterol and low density lipoprotein levels recorded during the first 6 years of the study. The authors speculate about possible explanations of these findings.