The relationship of pro-inflammatory markers to vascular endothelial function after acute stroke

Abstract

Purpose/Aim: Data from chronic stroke studies have reported reduced blood flow and vascular endothelial function in the stroke-affected limb. It is unclear whether these differences are present early after stroke. First, we investigated whether vascular endothelial function in the stroke-affected limb would be different from healthy adults. Second, we examined whether between-limb differences in vascular endothelial function existed in the stroke-affected arm compared to the non-affected arm. Last, we tested whether reduced vascular endothelial function was related to pro-inflammatory markers that are present early after stroke.

Materials and methods: Vascular endothelial function was assessed by flow-mediated dilation (FMD) in the brachial artery within 72 h post-stroke. All participants withheld medications from midnight until after the procedure. Ultrasound scans and blood draws for pro-inflammatory markers occurred on the same day between 7:30 am and 9:00 am.

Results: People with acute stroke had significantly lower FMD (4.2% ± 4.6%) than control participants (8.5% ± 5.2%, p = 0.037). Stroke participants had between-limb differences in FMD (4.2% ± 4.6% stroke-affected vs. 5.3% ± 4.4% non-affected, p = 0.02), whereas, the control participants did not. Of the pro-inflammatory markers, only vascular cell adhesion molecule-1(VCAM-1) had a significant relationship to FMD (stroke-affected limb, r = -0.62, p = 0.03; non-affected limb, r = -0.75, p = 0.005), but not tumor necrosis factor alpha nor interleukin-6.

Conclusions: Vascular endothelial function is reduced starting in the early stage of stroke recovery. People with higher levels of VCAM-1 had a lower FMD response.

Keywords: Flow-mediated dilation; acute stroke; inflammatory markers; vascular endothelial function.

Figure 1

VCAM-1 Concentration and Limb Percent FMD in Stroke