High blood pressure, also called hypertension, can damage the kidneys and lead to chronic kidney disease (CKD). Blood pressure measures the force of blood against the walls of the blood vessels. Extra fluid in the body increases the amount of fluid in blood vessels and raises blood pressure even higher.
Narrow, stiff, or clogged blood vessels can also raise blood pressure. In this case hypertension can result from normal fluid levels, but blood flow is minimized due to plaque buildup on the inner walls of the arteries.
High blood pressure makes the heart work harder and, over time, can damage blood vessels throughout the body. If the blood vessels in the kidneys are damaged, they may stop removing wastes and extra fluid from the body. The extra fluid in the blood vessels may then raise blood pressure even more.