9. Biomarkers Explained - RDW

RDW is the red blood cell distribution width. It is part of a CBC with differential lab test. This is an important biomarker for vascular health and is usually misinterpreted. Traditionally, this marker is considered a barometer for anemia. In reality it is a marker for inflammation in vessels. Red blood cells must deform as they flow single file through capillaries. Capillaries constitute most of the blood vessels in the body. When the RDW broadens slightly, it is an indication of endothelial dysfunction. The broader the RDW, the more dysfunction. RDW elevated values are well studied as a marker for premature death because it measures vascular health quite accurately.