Blood pressure measures and ECG-defined myocardial infarction in an Iranian population: Tehran Lipid and Glucose Study

The purpose of this study was to describe blood pressure values in Iranian adults with ECG evidence of a myocardial infarction. High blood pressure is a risk factor and ECG can be diagnostic of coronary artery disease. In recent studies, the role of pulse pressure in predicting coronary artery disease has been suggested to be more important than that of blood pressure. From among participants of Tehran Lipid and Glucose study, data for 2479 men and 3060 women aged ≥30 years, not currently using any antihypertensive medication, were collected. The study used the mean of two separate blood pressure measurements for each individual. ECG findings of all subjects were coded according to Minnesota ECG coding criteria and they were categorized into 1) probable/possible myocardial infarction or 2) no myocardial infarction. ECG evidence of probable or possible MI was found in 1.2% of subjects (1.8% in men vs. 0.8% in women, p<0.001). Prevalence of ECG-defined MI in hypertensive cases was two-fold higher than in normotensives. Adjusted for age, sex, and body mass index, mean diastolic blood pressure was significantly lower in cases with ECG-defined MI than in subjects without MI (73 vs. 75 mmHg, p<0.03). There was no significant difference between pulse pressure and systolic blood pressure in all subgroups. In both normotensive/hypertensive and MI/no MI subgroups, pulse pressure was more strongly correlated with systolic rather than diastolic blood pressure. Pulse pressure, as a risk factor for cardiovascular disease, is better predicted by systolic blood pressure than diastolic blood pressure in both normotensive and hypertensive populations with or without ECG-defined MI.