A 60-minute lower limb hot water immersion reduced elevated biomarkers of endothelial activation (CD62e+) in patients with cervical spinal cord injury to levels similar to uninjured controls (P=0.05).
Observational (n=30)
Does acute lower limb hot water immersion improve vascular function and reduce biomarkers of endothelial activation in individuals with cervical spinal cord injury?
Acute lower limb heating reduces biomarkers of endothelial activation in individuals with cervical spinal cord injury, though it does not acutely change macro- or microvascular function.
Absolute Event Rate: 4.8% vs 7.6%
p-value: p=0.04
Cardiovascular diseases (CVD) are highly prevalent in spinal cord injury (SCI), and peripheral vascular dysfunction might be a contributing factor. Recent evidence demonstrates that exposure to heat stress can improve vascular function and reduce the risk of CVD in uninjured populations. We therefore aimed to examine the extent of vascular dysfunction in SCI and the acute effects of passive heating. Fifteen participants with cervical SCI and 15 uninjured control (CON) participants underwent ultrasound assessments of vascular function and venous blood sampling for biomarkers of endothelial activation (i.e., CD62e + ) and apoptosis (i.e., CD31 + /42b − ) before and after a 60-min exposure to lower limb hot water immersion (40°C). In SCI, macrovascular endothelial function was reduced in the brachial artery SCI: 4.8 (3.2)% vs. CON: 7.6 (3.4)%, P = 0.04 but not the femoral artery SCI: 3.7 (2.6)% vs. CON: 4.0 (2.1)%, P = 0.70. Microvascular function, via reactive hyperemia, was ~40% lower in SCI versus CON in both the femoral and brachial arteries ( P < 0.01). Circulating concentrations of CD62e + were elevated in SCI versus CON SCI: 152 (106) microparticles/µl vs. CON: 58 (24) microparticles/µl, P < 0.05. In response to heating, macrovascular and microvascular function remained unchanged, whereas increases (+83%) and decreases (−93%) in antegrade and retrograde shear rates, respectively, were associated with heat-induced reductions of CD62e + concentrations in SCI to levels similar to CON ( P = 0.05). These data highlight the potential of acute heating to provide a safe and practical strategy to improve vascular function in SCI. The chronic effects of controlled heating warrant long-term testing. NEW & NOTEWORTHY Individuals with cervical level spinal cord injury exhibit selectively lower flow-mediated dilation in the brachial but not femoral artery, whereas peak reactive hyperemia was lower in both arteries compared with uninjured controls. After 60 min of lower limb hot water immersion, femoral artery blood flow and shear patterns were acutely improved in both groups. Elevated biomarkers of endothelial activation in the spinal cord injury group decreased with heating, but these biomarkers remained unchanged in controls.
Coombs et al. (Fri,) conducted a observational in Cervical spinal cord injury (n=30). Lower limb hot water immersion vs. Uninjured controls was evaluated on Macrovascular endothelial function in the brachial artery at baseline (p=0.04). A 60-minute lower limb hot water immersion reduced elevated biomarkers of endothelial activation (CD62e+) in patients with cervical spinal cord injury to levels similar to uninjured controls (P=0.05).