Final answer:
Anemia in dialysis patients is primarily caused by decreased production of erythropoietin (EPO), a glycoprotein secreted by the kidneys that is essential for the formation of red blood cells.
Step-by-step explanation:
The primary cause of anemia in the dialysis patient is a decrease in the production of erythropoietin (EPO). EPO is a critical glycoprotein for erythropoiesis, which is the process of red blood cell (RBC) formation in the bone marrow. In healthy individuals, the kidneys produce about 85 percent of circulating EPO.
This EPO is crucial because it signals the bone marrow to produce RBCs, which are essential for transporting oxygen throughout the body. Patients with chronic kidney diseases, including those on dialysis, often experience a significant reduction in EPO production.
Since the kidneys are responsible for the majority of EPO synthesis, when they are not functioning properly, as in the case of renal failure, EPO levels drop, leading to decreased RBC production. This ultimately causes anemia, characterized by weakness and fatigue due to impaired oxygen transport to body cells.