Bedtime Aspirin May Be More Beneficial for Heart Patients

Patients at high cardiovascular risk who took aspirin at night had significantly reduced platelet reactivity compared with those who took aspirin in the morning, according to the results of a study.

Aspirin may offer better protection against adverse events in cardiovascular disease patients when taken at night than when taken in the morning, new research suggests.

A previous study found that hypertension patients who took their medication at night had better blood pressure control than those who took their medication in the morning. Researchers from the Leiden University Medical Center in the Netherlands were curious to see if a similar approach would improve outcomes for patients with cardiovascular disease, especially since platelet reactivity and the risk for cardiovascular events are highest in the morning. The current study, presented on November 19, 2013, at the American Heart Association’s Scientific Sessions in Dallas, compared blood pressure measurement and morning platelet reactivity in heart attack survivors who took aspirin before bed with those who took it in the morning.

The open-label study randomized 290 patients with cardiovascular disease to take 100 mg of aspirin either at bedtime or when they woke up in the morning for two 3-month periods. Blood pressure and morning platelet reactivity were measured at the end of each period. The results indicated that platelet reactivity during morning hours was significantly reduced by 22 aspirin reaction units among patients who took aspirin before bed compared with those who took it in the morning. In addition, patients in the bedtime dosing group did not suffer more side effects than those in the morning dosing group. However, there was no significant difference in the blood pressure measurement of patients taking aspirin at night and those taking it in the morning.

Although the study did not measure whether taking aspirin at bedtime reduced the risk for heart attack or stroke in patients with cardiovascular disease, the authors suggest that the reduced morning platelet reactivity may help decrease the risk of cardiovascular events during high-risk morning hours. However, the study involved a small sample size and short follow-up, so patients should continue to take aspirin at the time they prefer until the results are confirmed in larger studies.