MedWire News: Patients with psoriatic arthritis have an elevated risk of having subclinical atherosclerosis, irrespective of whether they have vascular risk factors, researchers report.

Lai-Shan Tam (Chinese University of Hong Kong) and colleagues measured carotid intima-media thickness (IMT) in 82 patients with psoriatic arthritis and 82 healthy controls matched for age, gender and ethnicity.

The researchers defined subclinical atherosclerosis as carotid IMT above the 95th percentile of that in the controls. They note that this definition is more stringent that the 75th percentile definition recently recommended by the American Society of Echocardiography.

By the researchers' definition, 37% of the psoriatic arthritis patients and 5% of the controls had subclinical atherosclerosis. The average IMT value was significantly higher in patients than controls, at 0.626 versus 0.740 mm, as was the maximum value, at 0.888 versus 0.722 mm. No control participant had plaques, compared with 18% of patients.

Most (90%) patients had low vascular risk according to the Framingham Risk Score (<10% over 10 years). Yet over a third (35%) of these low-risk patients had subclinical atherosclerosis.

Psoriatic arthritis and male gender were the only independent predictors of subclinical atherosclerosis in the whole group, increasing the risk 15.2 and 3.6 fold, respectively.

Among patients, the most notable independent predictors of atherosclerosis were elevated sugar and triglyceride levels.

"Of note is that the median sugar level in psoriatic arthritis patients with subclinical atherosclerosis was well below the normal limit," comment Tam et al in the journal Arthritis Care & Research.

"This finding raises our concern about the definition of normality in terms of fasting sugar level in patients with chronic inflammatory diseases."

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