(RxWiki News) Beyond the red, itchy patches in patients with psoriasis, other problems may lay beneath their skin.
A new study has found that people with severe psoriasis have nearly twice at risk for diabetes as patients without the skin condition.
"Exercise to help decrease diabetes risk."
The study, led by April Armstrong, MD, assistant professor in the department of dermatology at University of California, Davis, in Sacramento, looked at 27 other observational studies in their analysis.
The included studies compared how often patients with diabetes had psoriasis and were published in English between January 1980, and January 1, 2012.
Collectively, the studies included more than 314,000 patients with psoriasis compared to almost 4 million people without the disease.
These studies covered over 10 to 22 years of research and looked at both how often psoriasis patients developed diabetes and how many patients already had diabetes at the start of the study.
The studies gathered information from a variety of settings, including insurance claims, inpatient samples and large outpatient databases with medical records or billing codes.
Researchers ranked the quality of each study using a 6-point scale with scores of 4 to 6 as higher quality.
Overall, they found that patients with mild psoriasis are more than 1.5 times as likely to have diabetes than people without the skin disorder. Those with severe psoriasis had almost twice the risk of having diabetes.
Further, the risk of developing diabetes increases 27 percent among psoriasis patients.
"Our investigation found a clear association between psoriasis and diabetes," Dr. Armstrong said.
"Patients with psoriasis and their physicians need to be aware of the increased risk of developing diabetes so that patients can be screened regularly and benefit from early treatment."
Dr. Armstrong thinks that the immune pathways in psoriasis patients make them more likely to have diabetes.
"There is evidence that fat cells in psoriasis patients may not function normally," she said.
"These cells secrete inflammatory substances known as cytokines that increase insulin resistance in the liver and muscle and initiate destruction of insulin-producing cells in the pancreas."
The included studies did not look at subtypes or the severity of psoriasis and diabetes, the authors note.
They say that future research is needed to better understand how psoriasis and diabetes are linked, but their study adds to the growing research connecting psoriasis with cardiovascular problems and other immune system conditions.
For future, they plan on investigating the cells that line blood vessels in the body to understand how psoriasis starts.
The authors are also working with other places of research to create a network database to share information on patients with psoriasis.
For this study, the authors received grants from Abbott Laboratories, Amgen and Janssen Pharmaceuticals, Inc.
The study was published online October 15 in the journal Archives of Dermatology.