Relationship between orthostatic hypotension, internal carotid artery blood flow, and cognition in patients with cervical spinal cord injury.

INTRODUCTION

This study aimed to identify the distribution of orthostatic hypotension (OH) according to changes in internal carotid artery (ICA) blood flow in patients with cervical spinal cord injury (SCI), and to determine whether cognitive impairment is more prominent among patients with a certain level of ICA blood flow reduction.

METHODS

Forty-one patients diagnosed with cervical SCI were retrospectively analyzed and classified into two groups based on the results of a head-up tilt test and carotid duplex ultrasonography to measure ICA blood flow: those with a reduction of 21% or more (n = 26) and those without such a reduction (n = 15). Cognitive function tests were compared between the two groups.

RESULTS

Patients with an ICA blood flow reduction of 21% or greater demonstrated significantly lower cognitive scores than those without such a reduction (K-MMSE p = 0.028, MoCA-K p = 0.048; Hedges' g = -0.65 for both). In multivariable regression adjusted for age, sex, and education, greater ICA blood flow reduction remained associated with lower scores on both instruments (p = 0.038 and p = 0.033). Among 13 cognitive subdomains, only language and visuospatial construction remained significantly lower after correction for multiple comparisons.

DISCUSSION: This study suggests that the early assessment of ICA blood flow and cognitive function may be informative in the rehabilitation process for patients with cervical SCI. Whether such assessment can help identify patients who should be prioritized for formal cognitive assessment requires prospective evaluation.