What Causes Elevated Levels Of ESR?

Hello and Thank you! I have an elevated sed rate (57) and this is the case for years. My red blood cells are apparently large. I have type 1 diabetes, protien S difficiency (multiple PE s), an adrenal tumor, I am on insulin and xarelto. The sed rate issue has come again today. My question is what should I be educating my self regarding this issue.