It can be.
Thrombocythemia (another name for an abnormally high platelet count
) can predispose you to both venous and arterial blood clots.
As I am sure you can imagine, blood clots in the veins or arteries can be very serious health concerns.
The cause of the thrombocythemia and the level to which they are elevated are both important factors to consider in treatment.
Consult with a hematologist.