There has been quite a bit of buzz about the possible threats to heart health with testosterone replacement therapy (more on that later), but the media and lawyers’ ads are missing the more common issue: What is the link between therapy to replace testosterone and high blood pressure?
At the “heart” of cardiovascular disease lies the propensity of the body to form clots and blood pressure. Blood pressure changes often arise when blood becomes thicker. The true issue at hand is how testosterone affects the thickness of blood.
So, let’s take a look at how testosterone can make your blood thicker, and how that can relate to blood pressure changes in patients using this medication.
Testosterone has a suppressive effect on a peptide hormone called pepcidin. It was only recently discovered, but it is known to be a regulator of iron absorption. It is primarily made in the liver, and when suppressed, it can lead to increased iron stores in the blood.
It is the job of your bone marrow to make red blood cells (RBC’s), and a primary component is iron. When the bone marrow sees more iron, it makes more RBC’s. This is a good thing, to a point. Red blood cells hold hemoglobin, and hemoglobin carries oxygen. More oxygen is good, but more red blood cells may not be.
Obtaining more red blood cells and oxygen carrying capacity is the reason people who compete in endurance sports train in the mountains. If you are a marathon
runner or cyclist training at altitude, your body responds by making more RBC’s and helping you to breath more efficiently even in “thin air” environments. Blood doping is the easier, but illegal way around this.
With secondary erythrocytosis or secondary polycythemia (increases in RBC’s due to outside factors) there is a point where this can pose a health risk.
What Does Having Too Many Red Blood Cells Do?
Red blood cells are the solid portion of blood. So, if you increase the solid portion, but don’t increase the liquid portion (plasma), the solution becomes thicker. This higher viscosity blood exerts more pressure on the cardiovascular system.