Atherosclerosis is a disease of the arteries. In atherosclerosis, substances such as cholesterol get deposited in the inside of the arteries, resulting in the restriction of blood flow. This causes serious health problems.

Causes of atherosclerosis

Atherosclerosis begins when low density lipoproteins (LDL) molecules get oxidized by free radicals in the arteries. When the oxidized LDL comes in contact with the walls of the arteries, they deposit cholesterol on the walls. This stimulates the immune system to send white blood cells to the affected area to clean up the cholesterol. But the white blood cells cannot do this and they too get deposited at the artery wall. Ultimately, a mess of cholesterol, white blood cells, calcium and other substances form a structure called plaque on the inner wall of the artery. The plaque causes the artery wall cells to die and the wall becomes hard and narrow.

Atherosclerosis affects only medium and large arteries, particularly those carrying blood from the heart (arteries are blood vessels that carry blood away from the heart), to the brain, kidneys and legs.

Atherosclerosis usually starts in adolescence, but there are no symptoms. Symptoms begin to appear only in middle or old age when the artery gets blocked significantly.

Effects of atherosclerosis

The effects of atherosclerosis result from decreased flow of blood in the diseased arteries. When the plaque becomes large, the blood flow in the artery becomes restricted. The tissues and organs nourished by the plaque affected artery do not get enough oxygen.

The following are the effects due to different parts of the body when the artery taking blood to that part gets plaque affected

Brain – dizziness, numbness, slurred speech
Heart – severe chest pain
Legs – pain while walking, sores

After a period of time, the plaque becomes fragile and ruptures. This causes blood to clot in the artery. If the artery taking blood to a particular organ has a blood clot, this is what happens

Brain – stroke
Heart – heart attack
Kidney – hypertension, kidney failure
Legs – gangrene

Risk factors for atherosclerosis

• Smoking
• Diabetes
• Obesity
• High cholesterol
• Advanced age
• Lack of exercise
• Genetic factors
• Stress