Coronary flow reserve and asymmetric dimethylarginine levels: new measurements for identifying subclinical atherosclerosis in patients with psoriatic arthritis.

Objective. To identify the presence of subclinical atherosclerosis in patients with psoriatic arthritis (PsA) and healthy controls using intima-media thickness (IMT), coronary flow reserve (CFR), and the plasma concentration of asymmetric dimethylarginine (ADMA), to evaluate the correlations among ADMA. IMT, and CFR. Methods. The study involved 22 patients who fulfilled the ClASsification of Psoriatic ARthritis study group criteria for PsA and a cohort of 35 healthy controls with no history or current signs of coronary artery disease (CAD). Common carotid IMT was measured using high-resolution B-mode ultrasonography. Dipyridamole transthoracic stress echocardiography was used to evaluate CFR. Blood samples were obtained to assess ADMA levels. The clinical manifestations were recorded. All patients were treated with disease-modifying antirheumatic drug, but none had received any biological or steroid therapy. Results. Plasma ADMA levels were significantly higher in the patients with PsA (0.71 +/- 0.07 mu mol/l vs 0.48 +/- 0.07 mu mol/l; p = 0.00) and CFR was significantly reduced in that group (2.86 +/- 0.70 vs 3.3 +/- 0.43; p < 0.01) compared to controls. Common carotid IMT was greater in the patients with PsA, but the difference was not significant (0.64 +/- 0.26 mm vs 0.62 +/- 0.5 mm; p = 0.65). There was a significant correlation between CFR and plasma ADMA levels in the PsA group (R = 0.28; p < 0.01), but no correlation between plasma ADMA levels and IMT (R = 0.02; p = 0.32), Disease Activity Score 28 (p = 0.52), or Psoriasis Area and Severity Index (p = 0.98). Conclusion. Our patients with PsA showed a profile of subclinical atherosclerosis. ADMA may be a useful marker of endothelial dysfunction in PsA. (First Release June 1 2011; J Rheumatol 2011;38: 1661-4; doi:10.3899/jrheum.100893)