Electrocardiographic age trends in amplitudes and intervals were studied in apparently healthy men aged 20 to 60 years in Greece, Italy and the United States where the demonstrated frequency of manifest coronary heart disease and mortality is greatly different. It was found that among apparently healthy men from these contrasting countries there are common and similar electrocardiographic trends with age. These trends consist of lowered wave amplitudes, prolonged durations and leftward shift of axis. They are not of the order of magnitude of "borderline or abnormal" clinical evaluations. The relative contribution of "disease" and "physiological aging" to the age changes in the electrocardiogram is not elucidated in this study. However, the findings suggest that several of the minor electrocardiographic changes that develop with age are phenomena common to man; they occur independent of body weight and blood pressure, and possibly independent of the degree of asymptomatic atherosclerosis of the major coronary arteries. It is clearly demonstrated that electrocardiographic age trends in healthy men provide neither a sensitive index of latent coronary heart disease in a population nor of population differences in coronary artery disease. The complexity of age effects on the electrocardiogram is explored here, and sources of bias and error in their study are elaborated.
Bibliographical noteFunding Information:
* From the Laboratory of Physiological Hygiene, University of Minnesota, Minneapolis, Minn. The data herein were collected under an international program of cardiovascular studies supported by the U. S. Public Health Service Grants HE-04697, HE-04672, HE-06090 and HE-06314 and by a grant from the American Heart Association.