If high blood pressure goes untreated it can lead to what’s known as renal artery stenosis, in which increased pressure on the arteries causes them to compress or harden, thereby restricting blood flow to the kidneys (via Cardiovascular Institute of America). According to the American Heart Association (AHA), damage to the kidney’s arteries prevents the organ’s blood vessels from doing their job of maintaining balanced levels of fluids, salts, acids, and more within the body. Additionally, all that added pressure on the blood vessels slows our kidneys’ filtration rate, which can increase the risk of fluid retention or the buildup of waste products in the blood, such as creatine. Normally discharged from the body through urination, having greater levels of creatine in our blood means that the kidneys aren’t working as they should be, explains the Cleveland Clinic. Because of creatine’s effects on the kidneys, those with kidney issues should not take creatine supplements.
A person with untreated hypertension may also experience proteinuria, an excess of protein in one’s pee. While not considered a disease on its own, proteinuria is an indicator that the kidney’s filtration structures have suffered damage and are allowing too much protein through into urine.