CHAPTER 8

Dangers of Hypertension

PART 1 Damage to the Brain

Hypertension is strongly associated with atherosclerosis, or hardening of the arteries. Atherosclerosis causes hard plaques to form in your arteries, slowing or blocking blood flow altogether. Blockage of the large arteries supplying blood to your brain, and weakening of the brain’s smaller blood vessels, makes them susceptible to stroke. READ MORE

Sometimes plaques rupture: the interior of the plaque breaks through the fibrous cap. This causes the immune system to form a blood clot over the rupture, just as it would for a wound on the surface of the skin. If a carotid artery leading to the brain is blocked, it can cause a stroke. If the clot forms in a more distant vessel, but breaks off and travels through the bloodstream, either a stroke or a heart attack may result.

Trouble with Memory or Understanding
Difficulties with memory or understanding concepts are more common in people with hypertension. People age 45 or over who have high diastolic blood pressure, which is the bottom number of a blood pressure reading, are more likely to have cognitive impairment, or problems with their memory and thinking skills, than people with normal diastolic readings.

Hypertension in midlife has also been confirmed as a risk factor for the development of dementia in late life. LESS

PART 2 Kidney Disease

The kidneys are particularly susceptible to damage from hypertension. No other organ in the human body is so densely packed with capillaries as the kidneys. Hypertension can damage these tiny blood vessels and disrupt the ability of your kidneys to filter waste products from your blood. In a hypertensive kidney, connective tissue overtakes the normal tissue that surrounds the glomeruli (tiny ball-shaped structures, composed of capillaries, that filter the blood). The capillaries shrink and harden, leaving the glomeruli unable to function. READ MORE

Hypertension can also damage the arteries that supply the kidneys, potentially leading to kidney disease and kidney failure.

What’s more, the kidneys have a major role in keeping blood pressure at healthy levels. They secrete an enzyme that causes blood vessels to constrict as well as a hormone that increases the volume of blood in the bloodstream. If the kidneys are damaged and these functions are impaired, hypertension can become even worse. LESS

PART 3 Vision Damage

Your body’s tiniest blood vessels are its capillaries, which are so fine that it would take ten of them, lined up side by side, to form the thickness of a human hair. Because they’re so thin, they’re very fragile. Hypertension can cause the capillaries in your eyes to rupture. It can also damage the capillaries that supply blood to your retina, and can cause the vessels that supply blood to the optic nerve to become blocked. The results may be blurred vision and even blindness.

PART 4 Enlarged Heart

When you have high blood pressure, the heart muscle thickens in an effort to pump more vigorously against the higher blood pressure in your vessels. The heart becomes strained and enlarged, and its blood vessels may be damaged. Unlike other muscles in your body, the heart becomes weaker, not stronger, as it becomes larger. An enlarged heart can eventually result in congestive heart failure. The symptoms are shortness of breath, dizziness, irregular heartbeat, heart palpitations, and fluid retention.