Psoriasis can be a maddening disease. Patches of thick, inflamed skin covered with silvery scales form here and there on the patient's body, often on the elbows, knees, other parts of the legs, scalp, lower back, face, palms, and soles of the feet. They usually itch or feel sore, and the more of the patches there are, generally, the worse the person suffers.
And because psoriasis is a genetic condition that causes inflammation by striking at the immune system, it can have other health effects. An estimated 10-30% of people with psoriasis also develop psoriatic arthritis, which causes pain, stiffness and swelling in and around the joints, according to the National Psoriasis Foundation.
Psoriasis sufferers also have higher rates of cardiovascular disease and other systemic health problems, said Jennifer Cather, MD, a Dallas dermatologist and a member of the Baylor University Medical Center's Division of Dermatology. "Often patients think psoriasis is just a rash, [but] it is a systemic inflammatory disease with far-reaching affects," Cather said. "Patients should be aware of that and understand that controlling that systemic inflammation can help with other diseases."
That's a message doctors are looking to share during August, Psoriasis Awareness Month. Until recently, there was little that could be done about the systemic damage done by psoriasis. Sufferers used topical creams to ease their itches or aches, or underwent expensive ultraviolet light treatments that disrupted the surface spread of psoriasis but did not address the underlying problems within the immune system.
But the past few years have seen the development of a new wave of drug treatments known as biologics. These medications do what previous treatments could not--go after the root of the problem by influencing the immune system.
"It's really changed the way we can treat psoriasis," said Lawrence Green, MD, assistant professor of dermatology at George Washington University School of Medicine in Washington, D.C. "It really has made life much more tolerable for patients."
Psoriasis occurs when the body's immune system is somehow mistakenly triggered, which speeds up the growth cycle of skin cells, according to the National Psoriasis Foundation. Normal skin cells mature and fall off the body in 28 to 30 days. A psoriatic skin cell takes just three to four days to mature and move to the surface, and, instead of falling off, the cells pile up and form lesions. According to the National Institutes of Health, as many as 7.5 million Americans have psoriasis.
Biologics are made from human or animal proteins, and they treat psoriasis by going after the overactive immune cells causing the disease. "They are based on natural processes," Green said. "They're similar to chemicals or compounds we already have in our system. They help lessen immune responses. They help soak up or diminish the extra inflammatory compounds."
Currently, five biologics are approved by the U.S. Food and Drug Administration for treatment of psoriasis, and three of those five are approved for psoriatic arthritis. Biologics are effective, and they also are more affordable than ultraviolet therapy, the other leading treatment for dealing with medium-to-severe cases of psoriasis, according to dermatologists.
Ultraviolet light kills the immune cells in the skin that are causing the problem, Cather said. The problem is, a person must come in three to five times a week for treatment, racking up hundreds of dollars in co-payments.
Biologics, by comparison, are self-administered through injection. The patient usually must inject the medication somewhere between twice-weekly to once every other week, Cather said.
Patients undergoing biologic therapy need to have periodic re-evaluations by their dermatologist to check for the development of new symptoms, including infections and potential cancers, according to guidelines issued earlier this year by the American Academy of Dermatology.
To learn more about psoriasis, visit the U.S. National Library of Medicine.
HealthDay News, August 25, 2008