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The relationship between a history of hypertension and the quality of its control in routine clinical practice and the risk of acute myocardial infarction was examined in a multicenter, casecontrol study conducted in Argentina between November 1991 and August 1994, within the framework of the FRICAS study. The cases were 939 patients with acute myocardial infarction and without a history of ischemic heart disease. The controls were 949 subjects identified in the same centers as the cases and admitted with a wide spectrum of acute disorders unrelated to known or suspected risk factors for acute myocardial infarction. The odds ratios and the 95% confidence intervals were derived from multiple logistic regression equations, including terms for age, gender, education, social status, exercise, smoking status, cholesterolemia, history of diabetes, body mass index, and family history of myocardial infarction. The quality of hypertension control was assessed with the most recent blood pressure reading reported by the subjects. Seventy-two percent of hypertensive cases and 62.6% of hypertensive controls had a history of antihypertensive therapy by self-report, when admitted to the medical center. The adjusted odds ratio for acute myocardial infarction due to hypertension was 2.58 (95% confidence interval, 2.08-3.19). The odds ratio was 2.42 (95% confidence interval, 1.88-3.11) when hypertensives reported that their greatest systolic value was below 200 mm Hg (moderate status) and 4.12 (95% confidence interval, 2.87-5.89) when it was above 200 mm Hg (severe status). When the highest diastolic blood pressure value was below 120 mm Hg (moderate status), the risk increased to 2.48 (95% confidence intervals, 1.90-3.24) and to 4.12 (95% confidence interval, 2.83-5.99) when it was above 120 mm Hg (severe status). If the most recent systolic blood pressure was ≥140 mm Hg, the odds ratio was 2.59 (95% confidence interval, 1.96-3.41), and it was 3.42 (95% confidence interval, 2.40-4.87) when the value was >140 mm Hg. If the most recent diastolic blood pressure was ≤90 mm Hg, the risk increased more than two fold (odds ratio=2.48; 95% confidence interval, 1.91-3.22), and if it was >90 mm Hg, it increased nearly four-fold (odds ratio=3.72; 95% confidence interval, 2.33-5.96). In smokers, the odds ratio was 2.28 in the absence of hypertension and increased to 7.51 when hypertension was present. In this Argentine population, hypertension is a strong and independent risk factor for acute myocardial infarction. In routine clinical practice, the control of blood pressure to levels below 140/90 seems to be required in order to reduce part (but not all) of the risk of acute myocardial infarction in hypertensive patients. [ABSTRACT FROM AUTHOR]

This case-control study, analyzed the role of coronary risk factors in acute myocardial infarction (AMI) in the elderly, and established the nature of this association and the degree of risk. Data were derived from an investigation (1060 cases and 1071 controls) conducted in 35 coronary care units from clinical centres in Argentina between November 1991 and August 1994. Our analysis was based on data collected from subjects over age 65. Cases were 427 patients with AMI and without history of ischaemic heart disease. Controls were 396 subjects identified in the same centres as the cases. Odds ratios (OR) estimates and their 95% confidence intervals (CI) were derived from multiple logistic regression equations including terms for age, education, social status, smoking status, history of diabetes or hypertension, body mass index and family history of coronary heart disease. The risk factors independently and strongly related to the risk of AMI were the following: hyperlipidemia (serum cholesterol > or = 240 mg/dl): OR = 1.76 (95% CI: 1.25-2.49), smoking habits: OR = 1.6 (95% CI: 1.06-2.4), hypertension: OR = 2.05 (95% CI: 1.51-2.73), diabetes OR = 1.71 (95% CI: 1.12-2.70), one relative with family history of coronary heart disease: OR = 1.36 (95% CI: 0.93-1.97) and two or more relatives: OR = 2.63 (95% CI: 1.21-5.71). This study confirms in the elderly the importance of hyperlipidemia, tobacco, hypertension, diabetes and family history of coronary heart disease as risks factors of AMI.