Background Inflammation plays a role in the pathogenesis of psoriatic arthritis (PsA) and also in the pathogenesis of atherosclerosis. The importance of vascular disease related to atherosclerosis in terms of cardiovascular(CVS) morbidity and mortality has become evident in PsA. Studies of central arteries in PsA demonstrate an increase in the thickness of the intimal layer, suggesting that PsA predisposes to atherosclerosis. The extent of peripheral arterial disease however, remains unestablished in these patients.
Objectives To determine the prevalence and extent of peripheral artery subclinical atherosclerosis in PsA patients with no previous history of cardiovascular disease(CVD) and the correlation with inflammatory markers and disease activity.
Methods The study population consisted of 54 patients (26 females, 28 males) with PsA, mean age 48.7 years, no previous history or clinically overt CVD and 42 healthy age-sex and traditional CVS risk factors matched controls. Both patients and controls were chosen to be non-smokers. Drug history including steroid duration and dosage and antirheumatic drugs was recorded. Of the 54 patients, 32 were active. Active disease being defined as ≥ 6 tender or swollen joints, psoriasis area and severity index (PASI) score ≥10, ESR > 28mm/hr and CRP≥10mg/dl. Laboratory measures performed included levels of the acute phase reactants high sensitivity C-reactive protein (hsCRP); ESR and fibrinogen, lipid profile and the proinflammatory cytokines IL-6 and TNF-alpha. Peripheral atherosclerosis was assessed using the non-invasive technique ankle-brachial blood pressure index(ABPI). The ABPI was measured at the posterior tibial and dorsalis pedis arteries using a Doppler ultrasound velocity detector. The normal ABPI is 1.0 and any value less than 1 was considered to indicate the presence of peripheral occlusive disease. Arteries were classified as obstructed at an ABPI less than or equal to 0.9; normal >0.9 and <1.3 and incompressible>1.3.
Results After controlling for traditional risk factors we found a higher prevalence of peripheral vascular disease in patients compared to controls (OR 1.98 95% CI 1.30-2.99). Amongst the PsA patients, 8 out of the 216 arteries (4%) were obstructed and 18 (8%) were incompressible compared to controls where 2 out of the 168(1.0%) were obstructed, p< 0.05 and 1 (0.5%) were incompressible, p< 0.01. In PsA patients, one or more abnormal arteries occurred in 16 of the 54 (30%) patients versus 2 out of 42 (5%) volunteers, p = 0.001. A significant correlation was seen between ABPI and disease duration, steroid use(dose and duration), PASI scores, hsCRP, ESR and fibrinogen respectively.
Conclusions The findings demonstrate an increased prevalence of an abnormal ABPI in PsA patients. ABPI seems to offer a simple, non-invasive tool for assessing peripheral artery diseas(PAD) in PsA paints and helps to identify patients who are at increased risk of atherosclerosis and further future CVD. Thus, PAD should not be overlooked in PsA patients. The implication of the findings of the present study is that all patients diagnosed with PsA should be regularly screened for PAD by a simple noninvasive test, such as ABPI in order to decrease the incidence of CVS morbidity and mortality in these patients.
Disclosure of Interest None Declared