Clinically unrecognized myocardial infarction in the Western Collaborative Group Study∗

doi:10.1016/0002-9149(67)90498-5

The American Journal of Cardiology

Volume 19, Issue 6, June 1967, Pages 776-782

https://doi.org/10.1016/0002-9149(67)90498-5 Get rights and content

Abstract

The occurrence of silent and other clinically unrecognized myocardial infarction prior to the study was observed in 42 men and in 31 new cases of infarction during a four and a half year follow-up of 3,182 men, aged 39 to 59 years, participating in an epidemiologic study of coronary heart disease. Among subjects aged 39 to 49 years, a statistically significantly higher frequency of unrecognized infarction occurred in those with a parental history of coronary heart disease, higher annual income, fasting serum triglycerides exceeding 150 mg./100 ml. and in those who exhibited the Type A behavior pattern, compared with subjects without such attributes. A higher frequency also was observed in the younger subjects who were cigarette smokers compared with former smokers and nonsmokers of cigarettes and in those with elevated blood pressure compared to those with normal pressure, but these differences were not statistically significant.

A significantly higher incidence of unrecognized infarction also was observed in all subjects with elevated serum beta/alpha lipoprotein ratios compared to those with lower ratios. This appears to be particularly striking since there were no significant differences in the incidence of such infarction among subjects with elevated serum cholesterol levels compared to those with low levels.

Most cases of unrecognized infarction were associated with the Type A behavior pattern, and this was independent of the blood pressure, serum lipid or lipoprotein levels, cigarette smoking, parental history or any of the other factors under study.

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There are more references available in the full text version of this article.

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^☆: This study was supported by U. S. Public Health Service Research Grants HE-03429 and HE-05151 and grants from the American Heart Association and the Irwin Strasburger Memorial Medical Foundation of New York.

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Clinical studyClinically unrecognized myocardial infarction in the Western Collaborative Group Study∗☆

Abstract

J. Chron. Dis.

The “silent coro-nary”; the frequency and clinical characteristics of unrecognized myocardial infarction in the Framingham Study

Ann. Int. Med.

Totally asymptomatic myocardial infarction: An estimate of its incidence in the living population

Arch. Int. Med.

A predictive study of coronary heart disease. The Western Collaborative Group Study

J.A.M.A.

Coronary heart disease in the Western Collaborative Group Study. A follow-up experience of two years

J.A.M.A.

Clinical study
Clinically unrecognized myocardial infarction in the Western Collaborative Group Study^∗☆