YES... in conditions like polycythemia
vera there is an increased production of rbc's and thickening of the blood occurs in such cases we cannot get accurate hba1c values. so dont bother much about hba1c but your hemoglobin
will increase and hematocrit
will increase. doctor has to do phlebotomy
or removal blood from you to get the hematocrit to normal. because of removal of blood, the viscosity of your blood will decrase so the further damage like clots formation in the vessels can be prevented.