The psoriatic difference
Study examines how psoriatic arthritis patients compare
Dr. Lisa Mandl is in an ideal resource to learn more about how patients with psoriatic arthritis compare with patients who have osteoarthritis.
Mandl is an assistant attending physician at the Hospital for Special Surgery in New York City, which is known for hip and knee replacements. As a recipient of a one-year, $50,000 Discovery Grant from the National Psoriasis Foundation, she is comparing cases of patients who were diagnosed with these two types of arthritis and how they fare after undergoing joint-replacement surgery.
Psoriatic arthritis is an a form of inflammatory arthritis that causes pain, stiffness and swelling in and around the joints. Up to 30 percent of people with psoriasis develop psoriatic arthritis. Osteoarthritis, the common form of "wear and tear" arthritis that is prevalent as people age, breaks down cartilage in joints, often causing bones to rub against each other.
Mandl, a rheumatologist and clinical epidemiologist, has gathered charts of 540 psoriatic arthritis patients and 1,000 osteoarthritis patients who underwent joint-replacement operations at the hospital during a four-and-a-half year period. Such a comparison rarely has been done, she said.
That's because more than 95 percent of total joint-replacement operations are performed on people with osteoarthritis, so there is a comparatively much smaller number of patients with psoriatic arthritis available for evaluation, Mandl said. Differentiating between the two types is further complicated by the fact that some osteoarthritis patients have psoriasis.
Because psoriatic arthritis is an autoimmune disease, patients who have it are thought to be different in their response and outcomes to surgeries. For example, such patients may need joint-replacement surgery at a younger age than those with osteoarthritis. Psoriatic arthritis patients also may be more prone to infections after surgery, both due to their disease and because some drugs used to treat it further suppress the immune system.
Mandl sent out questionnaires to past patients in the two groups to determine factors including whether there are age or gender differences between the psoriatic arthritis and osteoarthritis groups; whether their hospital stay was shorter, longer or the same; and whether they experienced any complications such as infections, even up to two years post-surgery.
If differences are found — or even if they aren't — that will be important to providers who care for patients with psoriasis and psoriatic arthritis, Mandl said.