Increased Central Arterial Stiffness after Spinal Cord Injury: Contributing Factors,Implications,and Possible Interventions

Abstract

Individuals with spinal cord injury (SCI) experience life-threatening cardiovascular events and various autonomic consequences in addition to the well-appreciated motor and neurological impairments. As a result, cardiovascular disease is a major cause of death after SCI, corresponding to a two-to-fourfold increased risk of cardiovascular events. A combination of neuroanatomical changes, unstable blood pressure, and rapid deconditioning as a result of decreased physical activity likely contributes to accelerated cardiovascular disease progression after SCI. Aortic pulse wave velocity (aPWV) is considered the gold-standard technique for evaluating central arterial stiffness, which itself is a correlate for greater cardiovascular disease risk in healthy individuals and a plethora of clinical conditions. In this review, we discuss central arterial stiffness after SCI, and demonstrate that it is consistently elevated in this population 2–3 m/sec, which corresponds to a 30–45% increased risk of cardiovascular mortality and an approximate 40-year acceleration of age-related cardiovascular decline. The potential factors contributing to increased central arterial stiffness are also reviewed in light of the available literature, including autonomic disruptions, blood pressure instability, metabolic changes, and physical inactivity. Further, measurement techniques, risk factors, cardiac dysfunction, and differences in arterial stiffness from able-bodied populations are discussed. Finally, potential therapeutic interventions for preventing or improving central arterial stiffening are also explored, including dietary, physical activity, and pharmacological strategies.