Inverse association between arterial stiffness and perceived fatigue independent of disability status and BMI in multiple sclerosis.

INTRODUCTION: Multiple sclerosis (MS) is an immune-mediated, neurodegenerative disease of the central nervous system. Fatigue represents one of the most prevalent and limiting symptoms of MS, and is associated with vascular dysfunction, notably increased arterial stiffness.

OBJECTIVE: This study examined the relationship between arterial stiffness and perceived fatigue in persons with MS.

METHODS: The sample of 52 persons with MS (71.2% Female; Age: 46.7 ± 12.3 yrs.) completed arterial stiffness and fatigue assessments as baseline for an exercise training intervention. Applanation tonometry measured arterial stiffness, pulsatility and waveform characteristics, and yielded the following outcomes: carotid-femoral pulse wave velocity (cfPWV), carotid pulse-pressure (cPP), and aortic augmentation pressure (AP). Perceived fatigue was measured using the Fatigue Severity Scale (FSS).

RESULTS: The mean (SD) scores for cfPWV, cPP, and AP were 7.0 ± 1.8 m/s, 35.7 ± 8.8 mmHg, 8.2 ± 6.2 mmHg, respectively. The mean (SD) FSS score was 4.6 ± 1.4 and indicated elevated fatigue. There were statistically significant (p < .05) inverse correlations between cfPWV (r = -.32), cPP (r = -.37) and AP (r = -.32) with FSS scores, and the correlations remained significant even after controlling for disability, body mass index, age, and sex.

CONCLUSION: Our results indicate a consistent pattern of inverse relationships between arterial stiffness, pulsatility, and waveforms with fatigue independent of disability, body mass index, age, and sex in MS. This could be explained by lower sympathetic activation linking higher arterial stiffness, pulsatility and augmentation pressure with lower fatigue in persons with MS.