Migraine and coronary heart disease mortality: a prospective cohort study
The bottom line is that migraine is a systemic disorder, most likely a result of altered mitochondrial function and / or oxidative stress. These dysfunctions are not limited to the brain, but rather have an effect everywhere in the body, playing a role in most, if not all, chronic diseases.
So, if this is the case, then finding increases in other diseases like heart disease should be no big surprise. So, the ONLY best way to approach migraine treatment is to look at the entire patient and make global lifestyle changes to improve the way their neurons are functioning.