What Is Psoriasis?

What is psoriasis? This chronic, non-contagious immune system disease affects the skin.

The Cause of Psoriasis
Psoriasis is believed to be a genetic disorder that causes the immune system to mistakenly react as if it is under attack. This immune response results in inflammation - this means an attack on your skin from the inside out.

Other causes or triggers include cold dry weather, stress, respiratory infections, certain medications and skin injuries. When you have psoriasis, your body produces skin cells too quickly, speeding up your skin cell renewal process. This means that the new cells will accumulate before your skin has a chance to shed old skin cells.

Psoriasis Symptoms
This double accumulation of both dead and new skin cells causes red, crusty, thick, flaky patches of skin topped with loose silver-colored scales. Usually these patches are found on the elbows, knees, hands, feet, scalp and lower back, though they can appear anywhere. This skin itches and burns.

Nail disorders are also common among psoriasis sufferers, ranging from yellowish coloration to separation from the end of the nail bed. Psoriasis can cause beyond the skin's surface, too, and is often linked to arthritis, causing joint swelling, pain and tenderness.

Who Gets Psoriasis
Only about 2.5 to 3 percent of the US population has psoriasis. The disease is just as common in men and women across all socioeconomic backgrounds. Psoriasis most commonly crops up during young adulthood or between the ages of 11 and 45. About one-third of sufferers have parents with the disease. Smokers have a higher risk of developing psoriasis; if a smoker does develop a case, symptoms may be more severe and last longer. Women who gained weight during early adult life also have a higher risk of having psoriasis.