Aspirin at bedtime cuts morning heart attack risk

Taking aspirin at bedtime instead of in the morning might reduce acute heart events, according a new study presented at the American Heart Association's Scientific Sessions 2013.
There is a body of research that suggests the majority of heart attacks occur in the morning. So taking aspirin before bedtime may be the better bet as it allows time for the medication to thin the blood, which reduces the risk of heart attack.

http://www.sciencedaily.com/releases/2013/11/131119193632.htm