Pulse pressure is associated with walking impairment in multiple sclerosis

Persons with multiple sclerosis (MS) have reduced gait performance and this is associated with disability and disease progression. The current study sought to test the hypothesis that higher central (aortic and carotid) and peripheral (brachial) pulse pressure (PP), manifestations of ventricular-vascular uncoupling related to increased arterial stiffness and pressure from wave reflections, would be associated with reduced gait performance in persons with MS. Participants consisted of 33 individuals with MS and 33 age/sex matched controls. Central blood pressure (BP) was assessed via applanation tonometry. Brachial BP was measured using an automated oscillometric cuff. PP was defined as systolic BP - diastolic BP. Gait performance was measured as 6-minute walk (6MW) distance. Within the sample with MS, the 6MW distance was significantly associated with brachial (r = -.49, p <.005), aortic (r = -.52, p <.001), and carotid (r = -.57, p <.001) pulse pressure. There was no association between any PP measure and 6MW distance in controls (p > 0.05 for all). In conclusion, PP is a predictor of gait performance in persons with MS. These findings suggest that vascular senescence and altered ventricular-vascular coupling may contribute, in part, to the deterioration of physical function in persons with MS.