Relationship between ambulatory blood pressure monitoring values and future occurrence of ischemic cerebrovascular and coronary events in hypertensive patients.

OBJECTIVES: To evaluate in a prospective study the relationship between 24-hour ambulatory blood pressure monitoring (ABPM) values and the occurrence of nonfatal ischemic cerebrovascular and coronary events in treated hypertensive patients. METHODS: Out of 8780 ABPM recordings we identified 79 hypertensive patients (both genders) who suffered a first nonfatal ischemic event, either cerebrovascular (stroke or transient ischemic attack) (STR/TIA, n = 48) or coronary (myocardial infarction, angina or coronary bypass/PTCA) (COR, n = 31) and 223 control-hypertensive patients (CTR) without any events during the same period who were fully matched (at the time of ABPM) for age, gender, antihypertensive therapy, presence of dyslipidemia or diabetes, and casual blood pressure (BP), in the proportion of 1 STR/TIA to 3 CTR and 1 COR to 6 CTR. Matched groups were compared for various ABPM parameters. RESULTS: On average, the time between ABPM and the occurrence of STR/TIA and COR events was respectively 32.4 (1 to 88) and 28.0 (1 to 73) months. For similar values of matched variables significant differences (p < 0.05) were observed between STR/TIA vs. CTR in 24-hour systolic BP (147.4 +/- 20.6 vs. 140.1 +/- 14.9 mmHg), daytime systolic BP (151.6 +/- 21.8 vs. 144.6 +/- 15.2 mmHg) and nighttime systolic BP (138.5 +/- 21.2 vs. 130.9 +/- 16.0 mmHg), and between COR vs. CTR in 24-hour systolic BP (143.5 +/- 19.5 vs. 135.2 +/- 15.6 mmHg), daytime systolic BP (146.3 +/- 20.5 vs. 139.6 +/- 15.9 mmHg) and nighttime systolic BP (138.1 +/- 19.7 vs. 126.2 +/- 16.4 mmHg), BP on rising (146.2 +/- 31.7 vs. 133.6 +/- 19.9 mmHg) and blunted nighttime BP dipping (5.3 +/- 7.4 vs. 9.60 +/- 6.0%). Versus CTR, STR/TIA showed a lower percentage of dippers (27.7 vs. 44.4%) and a higher percentage of extreme dippers (10.6 vs. 6.3%), nondippers (48.9 vs. 41.7%) and inverted dippers (12.8 vs. 7.6%). Versus CTR, the COR group showed (p < 0.02) a lower percentage of dippers (21.9 vs. 46.8%) and extreme dippers (3.1 vs. 4.3%) and a higher percentage of nondippers (56.3 vs. 43.0%) and inverted dippers (18.8 vs. 5.9%). CONCLUSIONS: This prospective study in treated hypertensive patients shows that both high ABPM values and abnormal daytime/nighttime BP profiles are associated with later occurrence of ischemic cerebrovascular and coronary events independently of casual BP values and other cardiovascular risk factors. This reinforces the idea that ABPM is a powerful predictor of future cardiovascular events.