According to the National Center for Biotechnology Information (NCBI), psoriatic arthritis occurs in about one in 20 people suffering from psoriasis, a disease that causes itching, unpleasant red spots, scaly skin on the body. Patients with psoriatic arthritis often experience stiffness and muscle pain in their extremities, mainly at the tips of the fingers and toes and along the spine.
In the case of psoriatic arthritis, the immune system mistakenly attacks and destroys healthy cells and tissue as part of an abnormal immune response, causing inflammation of the joints and overproduction of skin cells. Most people with this condition experience skin psoriasis first and develop arthritis symptoms later.
However, for some people, joint pain and swelling can occur before skin symptoms appear. The exact cause of this disease is unknown but research suggests that certain genetic and environmental factors can increase your risk.
Editor's Note: This article was medically reviewed by George Krucik, MD.
Some people with psoriatic arthritis also experience gout, a type of arthritis associated with high levels of uric acid in the blood.
In a blinded study examining the connection between psoriasis and caffeine, patients suffering from psoriasis were treated, on one side of their body, with a topical cream containing 10% caffeine. On the other side we used a placebo cream was used. The researchers did not reveal to the patients which side had the caffeine cream and which side the placebo.
After surveying patients for a number of weeks, researchers found that caffeine cream is more effective in treating symptoms of psoriasis than placebo, which supports the use of topical caffeine in the treatment of psoriasis.
Caffeine and anti-rheumatic drugs
Doctors can prescribe anti-rheumatic drugs that modify the disease (DMARD) to help reduce joint inflammation in patients with arthritis and also to treat the symptoms of severe psoriasis. It is speculated that oral caffeine may reduce the effectiveness of DMARDs but the research published in the International Journal of Dermatology shows otherwise.
The researchers looked at patients who took a DMARD, such as methotrexate (Rheumatrex), and examined their daily caffeine consumption habits. No correlation was found between the individual consumption of caffeine and the effectiveness of their prescribed DMARD. The hypothesis that caffeine has a negative effect on the function of DMARDs has been shown to be valid.
Drop and caffeine
Some people with psoriatic arthritis also experience gout, a type of arthritis associated with high levels of uric acid in the blood. Uric acid deposits can damage joint tissue which, in turn, causes symptoms of arthritis. Gout episodes are characterized by severe disturbances of joint pain, often beginning in the big toe and continuing down the leg.
In a 2007 national health study published in Arthritis and Rheumatism, researchers found that coffee drinkers had lower levels of uric acid than those who did not drink coffee, suggesting that caffeine may play a role in the reduction of uric acid levels. However, this study focused on the ability of coffee to reduce the risk factors for gout but did not address its effects on the preexisting symptoms of gout.
Interpreting the research
At this time, there is little evidence of the potential of caffeine to relieve the symptoms of psoriatic arthritis. While it has been shown to reduce the risk of developing gout, more research is needed to determine if caffeine has significant anti-inflammatory properties.
If you suffer from psoriatic arthritis, talk to your doctor about your symptoms to determine the best course of treatment. Always discuss the options of medical treatment and lifestyle with your doctor and keep him informed of any changes in your condition.
About the author
Fatima Khan is an MS Candidate at Clinical Nutrition & Dietetics, NYU.