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Low-dose aspirin better taken at bedtime rather than morning

Patients taking low dose aspirin for secondary CV prevention derive more benefit by taking it at bedtime rather than the morning, according to research presented at the American Heart Association’s Scientific Sessions this week.

The Aspirin in Reduction of Tension II trial is the first study to explore the timing of aspirin intake among patients with cardiovascular disease.

In the randomised, open-label study, 290 patients took either 100 mg of aspirin upon waking or at bedtime during two 3-month periods. At the end of each period, ambulatory blood pressure and platelet activity was measured.

Aspirin intake at bedtime did not reduce blood pressure compared with intake on awakening - with a non-significant 0.1mmHg reduction in systolic and a 0.6 reduction in diastolic.

But platelet reactivity during morning hours was significantly reduced with bedtime aspirin intake by 22 aspirin reaction units (ARUs).

This could be clinically advantageous due to the higher risk of cardiovascular events seen during morning hours say the researchers.

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