How High Blood Pressure Causes Erectile Dysfunction

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Nobody knows exactly how high blood pressure causes erectile dysfunction and impotence. One leading theory is that the excess pressure in the blood vessels actually causes damage to small arteries in the penis.
Normally, these arteries dilate in response to sexual stimulation, allowing more blood to flow into the spongy tissue of the penis to produce an erection. It is thought that excessive pressure on these arteries may cause tiny tears, which the body then repairs. In response to these tears, the healed arteries become thicker, allowing them to better resist further damage. These thicker arteries, though, aren’t able to respond as fast, or as completely, to demands for extra blood, so they become a sort of dam in the flow of blood to the erectile tissues of the penis.
One problem with this theory is that some studies seem to show that how long a patient has had high blood pressure is not as important for predicting the risk of erectile dysfunction as is the actual severity of the high blood pressure. In other words, someone who has had moderate hypertension for twenty years sometimes appears to be at lower risk for erectile dysfunction than a young man who has had very serious hypertension for only a few months. In light of this, other theories of how high blood pressure contributes to erectile dysfunction have been proposed.