Hello, Thank you for your contact to healthcare magic. I understand your health concern, if I am your doctor I suggest you that there are many reason of polycythemia, one is idiopathic which do not have any reason. Some have reasons like high altitude, living in condition of low oxygen pressure etc. So you can find the cause from the list. I will be happy to answer all your future concern. Thank you, Dr Arun Tank Infectious disease specialist. Wish you a best health at health care magic.