Endothelial dysfunction in psoriatic arthritis patients: correlations between insulin resistance and disease activity

Abstract

Objective: Cardiovascular atherosclerotic comorbidities represent an important cause of morbidity and mortality in patients diagnosed with psoriatic arthritis. In both atherosclerosis and Psoriatic arthritis, inflammation plays a pivotal role. Psoriatic arthritis is considered as an independent risk factor for the development of atherosclerosis with accelerated evolution. Development of atherosclerosis is initiated by the endothelial cell dysfunction along with inflammation and insulin resistance. The main aim of the study was to evaluate the endothelial function in Psoriatic arthritis patients, and to identify if it is related to the insulin resistance and Psoriatic arthritis disease activity.

Patients and methods: In this case-control study, a group of 32 age and gender matched healthy controls was formed and compared to the group of 32 Psoriatic arthritis patients. We assessed the following parameters: Disease Activity in Psoriatic Arthritis Score, Homeostatic Model Assessment for Insulin Resistance, serum levels of the tumor necrosis factor alpha (TNFα), and the endothelial dysfunction by means of the flow-mediated dilation at brachial artery. The Student's t-test, the Pearson correlation and the ANOVA test were used to perform the statistical analysis of the data obtained; p-value <0.05 was considered as statistically significant.

Results: Compared to the patients in the control group, TNFα and Homeostatic Model Assessment for Insulin Resistance were increased (p-value <0.001), and flow-mediated dilation at brachial artery was decreased (p-value <0.001) in the disease group. In Psoriatic arthritis patients, significant correlations were found between Disease Activity in Psoriatic Arthritis Score and Homeostatic Model Assessment for Insulin Resistance (r=0.8143, p-value <0.001), and between Disease Activity in Psoriatic Arthritis Score and flow-mediated dilation at brachial artery % (r= -0.8376, p-value <0.001). Psoriatic arthritis patients treated with Methotrexate exhibited reduced values of Disease Activity in Psoriatic Arthritis Score and Homeostatic Model Assessment for Insulin Resistance and increased values of flow-mediated dilation at brachial artery, when compared with the untreated patients.

Conclusions: Endothelial dysfunction is present in Psoriatic arthritis patients and has a significant correlation with both, the course of the disease and the insulin resistance.