Association of blood pressure variability and cerebral infarction in elderly men with atherosclerosis

Objective , To investigate the influence of blood pressure variability on cerebral infarction in older men. Methods Ambulatory blood pressure was measured in 1527 elderly men ( older than 65 yrs) with atherosclerosis. All cases were divided into 2 groups: Six hundred and seven patients with cerebral infarction ( group A)and 920 patients without cerebral infarction ( group B). Smooth curve method was used to analyze each patient's ambulatory blood pressure data and the trend of each patient's blood pressure curve was portrayed. The differences between the actual blood pressure and the blood pressure on the curve was defined as blood pressure variability,and the blood pressure variability between the 2 groups was compared. Results The systolic blood pressure variability in 24 hours in group A was significantly higher than that in group B( [8.4'±2. 2]mm Hg vs [ 8.0 ± 2. 0 ] mm Hg, P ＜ 0. 01 ), especially for the systolic blood pressure variability in daytime( [ 8. 2 ± 2. 2 ] mm Hg vs [ 7. 8 ± 2. 1 ] mm Hg, P ＜ 0. 01 ). However, the systolic blood pressure variability at night was not significantly different between the 2 groups( [ 8.9 ± 3. 9 ] mm Hg vs [ 8. 7 ± 3.7 ] mm Hg,P ＞ 0. 05 ). There were no significant difference between the diastolic blood pressure of 24 hours( [5. 5 ± 3.8 ] mm Hg vs [5.5 ± 1.5 ]mm Hg,P ＞0. 05),during daytime([5.4 ± 1.5]mm Hg vs [5.3 ± 1.4] mm Hg,P ＞0.05)and nighttime ( [ 6. 1 ± 2.7 ] mm Hg vs [ 6. 1 ± 2. 6 ] mm Hg, P ＞ 0. 05 ). Conclusion In elderly men with atherosclerosis,cerebral infarction was closely related to systolic blood pressure variability,but independent of nighttime systolic blood pressure and diastolic blood pressure variability. Key words: Elderly men;  Blood pressure;  Blood pressure variability;  Cerebral infarction; Mathematical method