Psoriasis is an incurable, recurring disease of the immune system that can first strike at any age, causing dry, painful skin lesions that itch, crack and bleed. Psoriasis often also causes arthritic symptoms (known as psoriatic arthritis).
Psoriasis is not contagious, although the emotional scars it often leaves can also negatively impact a patient’s loved ones.
Psoriasis is common, with as many as 7.5 million Americans affected, according to the U.S. National Institutes of Health.
Psoriasis has a strong hereditary component. Scientists are identifying genes that give people susceptibility to psoriasis. This susceptibility is then believed to combine with other factors that “trigger” psoriasis in a susceptible individual. Skin injury and infections—like strep throat—are the most common factors that can trigger psoriasis flares. Stress is also widely believed to play a role. Diet does not appear to play a significant role in the disease, although obesity is more common among psoriasis patients than the general public, suggesting an association between the two that is still being investigated.
There is no precise figure on what percentage of those with psoriasis also have psoriatic arthritis, but it is believed to range somewhere between 10% and 35%. Psoriatic arthritis is a chronic, progressive and potentially debilitating inflammatory disease that causes painful joint inflammation, stiffness, tenderness and tiredness, and can cause bone damage.
Fortunately, for most people with psoriasis, the disease is mild. They might have patches of dry skin on their elbows or knees and be able to treat it with over-the-counter or prescription creams and lotions.
But for millions of Americans, psoriasis is a daily impediment, one that dramatically and negatively impacts their quality of life. For many, it is debilitating. A National Institute of Mental Health-sponsored study in the Journal of the American Academy of Dermatology found that “Patients with psoriasis reported reduction in physical functioning and mental functioning comparable to that seen in cancer, arthritis, hypertension, heart disease, diabetes, and depression.” Psoriasis hurts. Psoriasis itches. Some people have extensive coverage—on their arms, legs, trunk, face, and/or genitals.
Psoriasis is also associated with other serious diseases and conditions. People with psoriasis are at higher risk for heart attack, stroke, diabetes, and even death. Our knowledge of these “comorbidities,” or other diseases that are often found in people with psoriasis or psoriatic arthritis, are just now emerging from the research and many questions remain.
But what is even less well known is how devastating psoriasis can be emotionally and psychologically. It is not just a disease that harms the body. Psoriasis patients have a higher incidence of depression, and even of suicidal thoughts. The visible nature of psoriasis exacerbates its interference with intimacy and one’s sense of self. Self-esteem can take a hit.
Overuse of alcohol and tobacco are associated with psoriasis, as is obesity, but figuring out cause and effect is difficult and not yet resolved. Some experts believe people with psoriasis turn to these things to deal with the trauma of psoriasis, while others believe excessive alcohol, tobacco or weight gain can trigger psoriasis. Both theories may prove true. People with psoriasis should certainly seek to control their weight and consumption of alcohol and tobacco.
In normal skin, it takes about a month for skin cells to move from the bottom layer to the surface and slough off unnoticed in a continuous cycle. But in skin affected by psoriasis, the process can be sped up to 10 times the normal rate. These cells cannot be shed rapidly enough, so they build up on the surface, leading to the think, dry patches that are the hallmark of plaque psoriasis, the most common form of the disease. Redness and inflammation typically accompany the patches of dry skin.
Plaque psoriasis is the most common type of psoriasis and most often appears on the elbows, knees, scalp and back, although it can appear anywhere on the body, including the hands, feet, and genital area.
It is often triggered by illness, infections or stress, and is often worse in cold weather, although in other cases it is not possible to determine the cause of an outbreak. One way psoriasis can advance on one’s body is through the Koebner phenomenon, in which skin injury or trauma (or even rough scratching of the skin) can later lead to new spots of psoriasis.
Inverse psoriasis (also called flexural psoriasis) typically occurs in moist areas of the body and in the folds of the skin, including under the breasts or armpits and the genital area. Sweat, friction and body movement can add to the pain and inflammation of inverse psoriasis. It is more common in people who are overweight. It is typically smooth and inflamed, rather than dry and scaly.
Guttate psoriasis is a form of the disease that typically comes on rapidly in a flare of teardrop-shaped spots. About 10% of people with psoriasis will develop guttate psoriasis at some point, although it more often appears in children and young adults. It most often follows a strep throat infection.
This uncommon form of psoriasis usually appears on the hands and feet, with pus-filled sores that resemble blisters. But it can also be a widespread flare that can be life-threatening. One reason to avoid “cold turkey” quitting of corticosteroids is because it can trigger a flare of pustular psoriasis, even in a person with plaque psoriasis. That is why your physician will typically tell you to wean off steroids, rather than quit abruptly.
Erythrodermic psoriasis is a rare, severe and dangerous form of the disease. It usually entails widespread coverage with inflamed areas of skin that are red and painful, and giving off heat. Erythrodermic psoriasis requires prompt medical attention.
Psoriatic arthritis typically involves the skin symptoms of psoriasis (usually plaque or pustular) plus pain, swelling and stiffness in one or more joints. Most people with psoriatic arthritis also have psoriasis of the nails. About one million Americans have psoriatic arthritis. As with psoriasis, psoriatic arthritis can range from mild to severe and debilitating. It can also grow progressively worse, and lead to permanent bone damage. Treatments are now available that have been shown to stop the progression of the disease. Most common in the fingers and toes, psoriatic arthritis can also manifest itself in the back, neck, legs and/or elsewhere.
Psoriasis and psoriatic arthritis can—and should—be treated. Undertreatment of psoriasis appears to be a real problem, but treatment options for patients continue to expand and improve. If you have psoriasis or psoriatic arthritis, seek out treatment from a physician. You owe it to yourself!