People who suffer from psoriasis may want to pay extra attention to heart risks, since they may be at a greater risk for blocked arteries than those who don't have the skin disease -- although the risk increase is not that high, according to a U.S. study.
And the longer patients have psoriasis, the higher their risks are, said researchers, whose findings were published in the American Journal of Cardiology.
"One of the things that we've come to understand is that psoriasis is not a disease that's just limited to the skin," said April Armstrong of the University of California, Davis, who worked on the study.
Armstrong and her colleagues used records of patients who had undergone a heart scan called coronary angiography to compare the results of patients with and without psoriasis.
Psoriasis patients have patches of thick, red and scaly skin, which are thought to be caused by the immune system mistakenly attacking the body's own cells.
Among the nearly 9,500 patients included in the analysis, just over 200 were diagnosed with psoriasis. Compared to the other patients who underwent the heart screening, they were more likely to have a history of high cholesterol and to be heavier.
Overall, 84 percent of patients with psoriasis had narrowing of the arteries that supply blood to the heart -- a condition called coronary artery disease -- compared to 75 percent of patients without the skin condition.
The researchers also found that the longer patients had psoriasis, the greater this risks were.
"Our advice to patients with psoriasis is to make sure they get screened for their modifiable cardiovascular risk factors," said Joel Gelfand, a professor of dermatology at the University of Pennsylvania, Philadelphia.
These modifiable risk factors include smoking, blood pressure, cholesterol, glucose levels and body mass index (BMI), a measure of weight relative to height, added Gelfand, who was not involved with the study.
Armstrong said that while the study did not prove that the condition causes heart disease, the skin rash may be a sign that there is inflammation inside the body, too.
The findings fit with past studies that showed a connection between heart disease and inflammatory diseases such as rheumatoid arthritis, said Richard Krasuski, director of Adult Congenital Heart Disease Services at the Cleveland Clinic, who was not involved with the study.
"Certainly what they come up with makes biological sense," he added, although he cautioned that the rise in risk wasn't overwhelming and the findings were based on patients from only one medical center.