Increased burden of inflammation over time is associated with the extent of atherosclerotic plaques in patients with psoriatic arthritis

Aim To investigate whether a higher burden of inflammation is associated with more severe atherosclerosis in patients with psoriatic arthritis (PsA). Methods Patients from a large PsA cohort were analysed. The cumulative effect of inflammation was measured by a time-adjusted arithmetic mean of all measurements from the first visit to the clinic. The following variables were considered as predictors: Psoriasis Activity and Severity Index (PASI), erythrocyte sedimentation rate (ESR), white blood cell (WBC) count, tender and swollen joint counts, C-reactive protein, Psoriatic Arthritis Disease Activity Score (PASDAS) and Disease Activity for PsA (DAPSA). Vascular ultrasound of the carotid arteries was performed, and total plaque area was measured. This measure represented the extent of atherosclerosis and was considered the outcome of interest. The association between inflammation over time and atherosclerosis was assessed by regression models adjusted for age, sex and cardiovascular risk factors. Results A total of 235 patients with PsA were analysed. Patients with more severe atherosclerosis were older (p<0.001), more likely to be obese (p=0.01), smokers (p=0.008) and have hypertension (p=0.001), diabetes (p<0.0001) and dyslipidaemia (p<0.0001). In a multivariate regression model adjusted for age and sex, higher ESR (p=0.009), WBC count (p=0.015) and DAPSA (p=0.04) were associated with more severe atherosclerosis. These associations were not significant after adjustment for traditional cardiovascular risk factors. No association was found between disease duration and atherosclerosis. Conclusions Exposure to an increased burden of inflammation is associated with more severe atherosclerosis in patients with PsA. This association may be mediated by traditional cardiovascular risk factors.