Chronotherapy With Aspirin for Reduction of Cardiovascular Disease

Aspirin is the cornerstone of preventive cardiovascular disease (CVD) treatment and bedtime intake of aspirin (chronotherapy) has been shown to reduce morning activity of platelets. It has been shown that platelet reactivity follows a clear circadian rhythm, with a peak of platelet reactivity during the morning (6-12 AM). Importantly, studies have shown in meta-analyses that high platelet activity is predictive of adverse cardiovascular outcomes in patients with stable CVD. Given this knowledge, it is highly likely that the morning peak of platelet reactivity contributes to the morning peak of cardiovascular events and that reduction of morning platelet activity prevents cardiovascular events during morning hours. This may be achieved by intake of aspirin at bedtime instead of on awakening. This study will be a comparative effectiveness research to determine the difference in major adverse cardiovascular events between the group with aspirin after awakening and placebo before bedtime and the group with placebo after awakening and aspirin before bedtime.