Psoriasis has been associated with other diseases like diabetes as well as increasing the risk of cardiovascular disease. New studies have been able to identify 14 different diseases associated with psoriasis.

Psoriasis is an autoimmune disease caused by the body mistakenly increasing the speed of skin cell growth. Psoriasis can occur on all parts of the body and symptoms could include itchy skin, inflamed areas of the body and scaly patches of skin. There is no cure for psoriasis and individuals have to undergo treatment, steroidal creams, moisturizers or systemic treatment via pill or injection, to manage the disease. While some diseases have been associated with psoriasis in the past, a new study has identified 14 specific autoimmune diseases which psoriasis suffers are more prone to get.

The study was led by Jashin J. Wu, MD, from the Kaiser Permanente Los Angeles Medical Center, and involved a study of 25,341 patients, average age of 49, with two or more types of psoriatic disease. The researchers, as a control, paired five individuals who did not have any psoriatic disease to a psoriatic patient matching them based on age, sex and length of enrollment in the insurance program.

The researchers studied 21 different autoimmune diseases to see if there was any association with psoriasis. Out of the patients, 10.6 percent had at least type of psoriatic arthritis. The study discovered that psoriasis increased the risk of getting one or two of 14 different autoimmune diseases.

According to researchers, patients with just psoriasis or psoriasis with psoriatic arthritis had 1.6-fold increased risk for at least one additional autoimmune disease and a 1.9-fold increased risk for at least two autoimmune disorders.

The three diseases that were most associated with psoriasis were rheumatoid arthritis, alopecia areata (spot baldness), celiac disease and systemic sclerosis. Systemic sclerosis affects connective tissue and could cause scarring, skin thickening, joint pain and sores on fingers or toes. Rheumatoid arthritis had the strongest association among the 14 diseases.

The other diseases that psoriasis sufferers were at a greater risk of having include Crohn's disease, Sjogren's syndrome (dry eyes and dry mouth), ulcerative colitis, chronic hives, lupus, Addison's disease, vitiligo, chronic glomerulonephritis, scarring of the lung and giant cell arteritis.

The researchers believe that there may be a common genetic or environmental cause for autoimmune diseases. Focusing on studying individuals with more than one autoimmune disease could help identify a potential cause for the diseases.

The study was published in the Journal of the American Academy of Dermatology.

Two researchers disclosed funding from pharmaceutical companies that were unrelated to the study.