TITLE:
The Antihypertensive Effect of ASA Lasts Less than 24 Hours?
AUTHORS:
I. Suomela, J. Varis, I. Kantola
KEYWORDS:
Acetylsalicylic Acid, Blood Pressure, Arterial Stiffness, Pulse Wave Velocity, Stiffness Index, Reflection Index
JOURNAL NAME:
World Journal of Cardiovascular Diseases,
Vol.5 No.3,
March
19,
2015
ABSTRACT: Objectives: Some studies suggest that acetylsalicylic acid (ASA) administered in the evening may have a lowering effect on the blood pressure. The purpose of this study was to measure the effect of the time of ASA administration on blood pressure, markers of arterial stiffness as well as various plasma parameters. Methods and Results: The study included 34 patients (20 men and 14 women) ranging in age from 47 to 82 years. Low-dose ASA (50 - 250 mg/day) was used by all the patients, first in the morning and later in the evening for three months. Home, office and ambulatory blood pressure and pulse wave velocity (PWV) were measured. Compared with the morning administration of ASA, significantly lower office systolic blood pressure (p = 0.017) and significantly higher carotid-femoral PWV (p = 0.010) as well as plasma triglycerides (p = 0.002) were found after the evening administration. There were no statistically significant changes in the average ambulatory blood pressure values, carotid-radial PWV or other parameters measured. However, the time of ASA administration seemed to affect the circadian variation in blood pressure. Conclusions: The results suggest that ASA administration may lower blood pressure, but for less than 24 hours. Our results should be verified by larger, randomized studies.