Story time on aspirin

USA Today, who brought us a dubious early signaling system for sudden cardiac arrest in a prior post, also gave us “Story Time!” on aspirin on the same day (link).

The article started with the conclusion: “Taking an aspirin before bed may reduce the chance of having a heart attack or stroke in the morning”.

What is the data used to support this cause—effect statement?

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The researchers looked at 290 patients with heart disease and were taking aspirin. They asked some to take the aspirin on waking and some at bedtime. The group that took the aspirin before sleeping had the same blood pressure but “significantly” lower platelet activity.

Then came Story Time. One of the researchers explained to the reporter: “Platelet activity is highest in the morning, and that is also the time most heart attacks and strokes occur. So if you reduce platelet activity during the morning hours, you might reduce heart attacks and stroke at that time.

I don’t know if the above assertion is true or not. I do know that the referenced study does not provide any evidence to support or refute this theory. I am not sure why the researchers do not follow this group of patients for a longer period of time to observe if the platelet activity reduction is correlated with fewer heart attacks and stroke.

(Story Time is the lullaby of data from a good but irrelevant study while telling stories almost purely based on theory.)

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One of the most annoying aspects of medical "science" is the abuse of the transitive relation: if A -> B, and B -> C, then A -> C. This works if -> is a certainty (which it is in pure math). Most of the time, in a statistical study, -> is a statistical significance, and the transitive breaks down. The non-transitivity is because in real life, there is almost never a single cause for illness or death; studies inevitably deal with single causes ("keeping all else equal"), and then researchers just link different studies up as if they are dealing with transitive algebra.