What Causes Pituitary Apoplexy?

Hypertension

Individuals who have systemic long-term high blood pressure (hypertension) can experience pituitary apoplexy. Hypertension is a condition where the force of the blood against the walls of the blood vessels as it is moving through them becomes too excessive for the blood vessels to handle. Blood vessels are designed to expand with greater blood volume and pressure, but can only do so to a certain degree. Beyond the expansion ability of the blood vessels to cope with increased blood volume and pressure, damage begins to take place in the walls of the blood vessels. 

This mechanism can take an immense toll on the smaller blood vessels around the body that weave their way through smaller structures such as the pituitary gland. While the exact mechanism of which high blood pressure causes an individual to experience pituitary apoplexy is not clear, it is thought to involve the damage that occurs in the small blood vessels that provide the pituitary gland with blood. Hypertension causes degenerative alterations in the microvasculature in the pituitary gland tissue, leading to a bleed that causes pituitary apoplexy.