Silent ST-T changes in an epidemiologic cohort study - A marker of hypertension or coronary heart disease, or both: The Reykjavik study

Objectives. We sought to evaluate the prognostic value and clinical characteristics associated with electrocardiographic (EGG) ST-T changes among men without other manifestations of coronary heart disease. Background. Recent achievements in secondary prevention and treatment of coronary heart disease have highlighted the importance of early diagnosis of both symptomatic and silent forms of the disease. The prognostic and clinical importance of ST-T changes in men with no other manifestations of coronary heart disease is still unclear. Do they reflect silent coronary heart disease or hypertension, or both, and what is their independent contribution to prognosis? Methods. The subjects were 9,139 men born in the years 1907 to 1934 and followed up for 4 to 24 years, On initial visit they were assigned to different categories of coronary heart disease on the basis of Rose chest pain questionnaire, hospital records, 12-lead EGG, history and physical examination. Results. The prevalence of silent ST-T changes among men without overt coronary heart disease was strongly influenced by age, increasing from 2% at age 40 years to 30% at age 80 years. triglyceride levels and worse glucose tolerance than men without such changes or other evidence of coronary heart disease. Their blood pressure was higher, and they more often had an enlarged heart or left ventricular hypertrophy and more often took antihypertensive medication, digitalis or diuretic drugs. Serum cholesterol levels were not different between the two groups. After adjustment for other risk factors, these silent ST-T changes had a risk ratio of 2.0 for death from coronary heart disease and 1.6 for subsequent myocardial infarction or angina pectoris. Conclusions. Silent ST-T changes that are ischemic by the Minnesota code are probably both a marker of silent coronary heart disease and high blood pressure. They define a distinct group of patients with a highly abnormal risk factor profile. Although not specific for coronary heart disease and often transient, they are associated with the development of every clinical manifestation of coronary heart disease and are independent predictors of reduced survival.