Why do people with advanced kidney disease commonly become anemic?

People with advanced kidney disease often develop anemia due to several factors:

1. Decreased Erythropoietin Production: Healthy kidneys produce a hormone called erythropoietin (EPO) that stimulates the bone marrow to produce red blood cells. In advanced kidney disease, the damaged kidneys produce insufficient EPO, leading to decreased red blood cell production.

2. Impaired Iron Utilization: Iron is an essential mineral for red blood cell production. However, in kidney disease, the kidneys' ability to convert vitamin D into its active form, which is necessary for iron absorption, is impaired. Additionally, inflammation associated with kidney disease can further decrease iron utilization.

3. Blood Loss: Advanced kidney disease can cause damage to the small blood vessels in the kidneys, leading to microscopic bleeding into the urine (hematuria). Over time, this chronic blood loss can contribute to anemia.

4. Inflammation and Uremic Toxins: Chronic kidney disease is associated with inflammation and the buildup of uremic toxins in the bloodstream. These factors can suppress the bone marrow's ability to produce red blood cells, contributing to anemia.

Anemia in advanced kidney disease can cause various symptoms, including fatigue, weakness, shortness of breath, dizziness, and pale skin. It can also worsen the progression of kidney disease and increase the risk of cardiovascular events. Therefore, regular monitoring of hemoglobin levels and appropriate treatment, such as erythropoietin stimulating agents, iron supplementation, and dietary modifications, are essential in managing anemia in individuals with advanced kidney disease.