Substance P concentration is associated with the inflammatory response and pain perception in patients with chronic pain in peripheral artery disease

Abstract

Previous studies indicate a significant role of the inflammatory response in the etiopathogenesis of peripheral artery disease (PAD) and chronic pain (CP). The aim of the study was to determine the relationship between the concentration of SP and the level/concentration of inflammatory mediators (pro-inflammatory cytokines, positive and negative acute phase protein, anti-inflammatory cytokines) and pain intensity in people suffering from chronic pain (CP) in the course of PAD. We examined 187 patients of the Department of Vascular Surgery. 92 patients with PAD and CP (study group) were compared to 95 patients with PAD without CP (control group). The relationship between SP and the level/concentration of fibrinogen, C-Reactive Protein (CRP), antithrombin III (AT), serum albumin, Interleukin 10 (IL-10), Tumor Necrosis Factor Alpha (TNF-α) and pain intensity (NRS) was analyzed. Statistical analysis was performed using the R program, assuming the level of statistical significance α=0.05. Patients with CP had significantly higher levels of fibrinogen (p<0.001), CRP (p<0.001), SP (p<0.001), IL-10 (p<0.001) and lower serum albumin levels (p<0.023). Higher SP concentration was associated with higher levels of IL-10, CRP and pain intensity. In both groups, SP concentration correlated negatively with the level of fibrinogen (p<0.001) as well as with albumin in the control group (p<0.001). Thus, there is a relationship between the concentration of SP and fibrinogen, along with CRP, IL-10 and the intensity of pain in people suffering from CP in the course of PAD and the level of albumin in the group without CP.