ASSOCIATION BETWEEN VARIABILITY IN SYSTOLIC BLOOD PRESSURE AND CARDIOVASCULAR EVENTS IN HYPERTENSIVE PATIENTS: 60 MONTHS FOLLOW UP

Abstract

Objective: To investigate the association between variability in systolic blood pressure (SBPV) and development of cardiovascular events (CVE): angina pectoris (AP), myocardial infarction (MI), cerebrovascular accident (CVA) and cardiovascular death (CVD) in hypertensive patients (pts), and to estimate whether SBPV could be a predictor of CVE and CVD. Design and method: 300 hypertensive pts (148 men and 152 women, mean age 67.7 ± 9.8y) were studied. The study comprised 3 visits (at the beginning, after 30 and 60 months) during a follow-up period of 60 months. Blood pressure values were defined by the arithmetic mean of three measurements at each visit. SBPV for each patient was defined using the standard deviation from 3 values of systolic BP (SBP-SD). In order to estimate distribution SBPV, quartiles of SBP-SD were introduced. High SBPV were defined as SBP-SD above the 4th and 3th quartile. Results: During follow up period, in 86 pts (28.7%) CVE were occurred: AP 18.7%, MI 7.7%, CVA 2.3%, CVD 4%. The first quartile included SBPV values < 5.81 mmHg, the second quartile 5.82–10.61 mmHg, the third quartile 10.62–17.08 mmHg, and the fourth quartile > 17.08 mmHg. Univariate analysis showed that there was a significant relationship between SBPV and CVE (OR = 1.305; 95% CI 1.223–1.393, p < 0.001). During 60 months follow up, the highest SBPV was recorded in the 3rd and 4th quartile in patients who had CVA (17.08 and 42.07, p < 0.01), in the 4th quartile in patients who had MI (25.18), and the lowest in patients with AP (4th: 29.16, 3th: 16.64, p < 0,01). A cut-off value of SBPV = 14.08 mmHg predicted the CVE with a sensitivity of 84.2% and specificity of 83.3%. A cut-off value of SBPV = 16.13 mmHg predicted the CVD with a sensitivity of 80.7% and specificity of 75.5%. Conclusions: Our results showed an association between increased SBPV and the development of CVE in hypertensive pts. Value of SBPV> 14.08 mmHg may be a useful marker for predicting future cardiovascular events, and value of SBPV> 16.13 mmHg may be a useful marker for predicting cardiovascular death.