Are Vascular Parameters Associated with Walking Impairment in Patients with Claudication?: Vascular Parameters and Walking Impairment in PAD.

Abstract Background The mechanisms underlying functional impairments in symptomatic PAD patients are controversial and poorly understood. Endothelial dysfunction and arterial stiffness have been proposed as potential mechanisms related to functional impairment in symptomatic PAD patients, however, more studies are needed to confirm these associations. Objective To analyze the association between vascular function and walking impairment in patients with peripheral arterial disease (PAD) and symptoms of claudication. Methods This was a cross-sectional study that included 68 patients with symptomatic PAD. All patients underwent an objective (Six-minute walk test [6MWT], 4-meter walk test) and a subjective (Walking Impairment Questionnaire [WIQ]) measurement of walking impairment. Vascular parameters measured were pulse-wave velocity (PWV) and flow-mediated dilation (FMD). Multiple linear regression was performed to investigate the association among walking impairment variables with vascular function parameters. Results No significant associations between the claudication onset distance (PWV: b=.060, p=.842; FMD: b=-.192, p=.456), 6MWT (PWV: b=.007, p=.975; FMD: b=.090, p=.725), WIQ distance (PWV: b=.337, p=.117; FMD: b=-.025, p=.895) WIQ speed (PWV: b=.320, p=.181; FMD: b=-.028, p=.497), WIQ stairs (PWV: b=.256, p=.204; FMD: b=-.228, p=.230), 4-meter usual walk (PWV: b=-.421, p=.107; FMD: b=-.338, p=.112), 4-meter fast walk (PWV: b=-.496, p=.063; FMD: b=-.371, p=.086) and vascular function were found. Conclusions In symptomatic PAD patients, vascular function is not associated to walking impairment, even when adjusting for comorbid conditions and diabetes. Keywords peripheral arterial disease; vascular function; functional capacity; six-minute walk test.