Renal Hypertension: How Kidney Disease Leads to High Blood Pressure

Renal hypertension, also known as renovascular hypertension, is high blood pressure caused by narrowing of the arteries that supply blood to your kidneys (renal arteries). This condition is often due to a buildup of plaque (atherosclerosis) in your arteries or other issues that reduce blood flow to your kidneys.

Consult the best nephrologist in Brooklyn, NY if you experience symptoms of renal hypertension at Doral Health and Wellness Urology Center.

Kidney disease can lead to high blood pressure (hypertension) through several mechanisms, all related to the kidneys’ role in regulating fluid balance and blood pressure. Here’s how kidney disease contributes to hypertension:

  • Impaired Fluid and Sodium Balance
    • How it works normally – Healthy kidneys filter waste and excess fluids from your blood, maintaining the proper balance of electrolytes, including sodium. This balance is important for controlling blood volume and, by extension, blood pressure.
    • In kidney disease – When your kidneys are damaged, they cannot efficiently remove excess fluid and sodium. As a result, fluid builds up in your blood vessels, increasing blood volume. The more fluid there is in the blood vessels, the higher the pressure on the vessel walls, leading to elevated blood pressure.
  • Overactivation of the Renin-Angiotensin-Aldosterone System (RAAS)
    • How it works normally – Your kidneys regulate blood pressure through the renin-angiotensin-aldosterone system (RAAS). When blood flow to your kidneys is reduced, your kidneys release renin, a hormone that activates angiotensin II. Angiotensin II constricts your blood vessels and triggers the release of aldosterone, which causes the kidneys to retain more sodium and water, increasing your blood pressure.
    • In kidney disease – If kidney function is impaired, the RAAS system may become overactive. Even when blood pressure is normal or high, your kidneys may continue to release renin, which leads to excessive production of angiotensin II, causing blood vessels to narrow and blood pressure to rise.
  • Damage to Blood Vessels
    • How it works normally – Your kidneys filter blood through small blood vessels called glomeruli, which help regulate blood pressure by controlling how much fluid is excreted or retained.
    • In kidney disease – Conditions like glomerulonephritis (inflammation of the glomeruli) or scarring from other diseases can damage these tiny blood vessels, impairing their ability to filter blood effectively. This disruption leads to an imbalance in fluid and sodium levels, contributing to high blood pressure.
  • Hormonal Imbalance
    • How it works normally – Your kidneys produce hormones like erythropoietin, which influences red blood cell production, and they help regulate hormones involved in blood pressure control.
    • In kidney disease – When kidney function is compromised, these hormonal pathways can be disrupted. For example, your kidneys may signal your body to retain more sodium and water than the necessary, raising your blood pressure.
  • Vascular Stiffness and Resistance
    • How it works normally – Your kidneys help maintain healthy blood vessels by regulating blood pressure and controlling sodium and fluid balance.
    • In kidney disease – Prolonged kidney damage can cause blood vessels to stiffen or narrow, increasing resistance to blood flow. This makes it harder for your heart to pump blood, leading to increased pressure in your blood vessels.

High blood pressure itself can damage the blood vessels in your kidneys, leading to further kidney dysfunction. This creates a cycle where kidney disease worsens high blood pressure, and high blood pressure further damages your kidneys.

In summary, kidney disease leads to high blood pressure by disrupting your kidneys’ ability to:

  • Regulate fluid and sodium levels.
  • Properly control the release of hormones that influence blood pressure.
  • Maintain healthy blood vessels.

These processes cause blood volume to increase, blood vessels to narrow, and blood pressure to rise. If left untreated, high blood pressure can lead to further kidney damage, heart disease, and other serious health issues. Therefore, managing blood pressure is important if you have kidney disease.

At Doral Health and Wellness Urology Center, our urologists and nephrologists in Brooklyn, New York can help you treat and manage your condition well. To schedule an appointment, you may call us at 1-347-384-5694 or visit our website at https://www.urologistbrooklyn.com/. You can also visit us at 1797 Pitkin Avenue, Brooklyn, New York 11212.