Spurious polycythemia has many other names, including relative polycythe-mia, stress erythrocytosis, stress polycythemia, benign polycythemia, Gaisböck’s disease, and pseudopolycythemia. Spurious polycythemia is characterized by increased hematocrit and normal or decreased red blood cell (RBC) total mass; it results from decreasing plasma volume and subsequent hemoconcentration. This disease usually affects middle-aged people and is more common in men than in women.
There are three possible causes of spurious polycythemia.
Conditions that promote severe fluid loss decrease plasma levels and lead to hemoconcentration. Such conditions include persistent vomiting or diarrhea, burns, adrenocortical insufficiency, aggressive diuretic therapy, decreased fluid intake, diabetic acidosis, and renal disease.
Hemoconcentration due to stress
Nervous stress leads to hemoconcentration by an unknown mechanism (possibly by temporarily decreasing circulating plasma volume or vascular redistribution of erythrocytes). This form of erythrocytosis (chronically elevated hematocrit) is particularly common in middle-aged men who are chronic smokers and have type A personalities (tense, hard-driving, anxious).