Abstract
Objectives: To describe the characteristics of cardiovascular autonomic neuropathy utilizing the Ewing test battery and to analyze its cross-sectional association with neurogenic orthostatic hypotension in patients with multiple system atrophy (MSA). Methods: A cross-sectional descriptive study was conducted on 40 MSA patients (mean age 61.28 ± 9.80) at Tam Anh General Hospital from January 2024 to May 2026. All subjects underwent a standardized battery of five Ewing tests (including the Valsalva maneuver, deep breathing test, orthostatic challenge, isometric handgrip test, and orthostatic blood pressure measurement) in accordance with the 2022 Movement Disorder Society (MDS) consensus criteria. Results: The mean Ewing score was 3.05 ± 1.02. The prevalence of neurogenic orthostatic hypotension was 55%, demonstrating a statistically significant positive correlation with vasomotor sympathetic failure assessed via the isometric handgrip test (p < 0.001) and baroreflex impairment evaluated via the Valsalva maneuver (p = 0.004). Notably, the concurrent manifestation of multiple autonomic failures (defined as ≥ 3 abnormal autonomic tests) was significantly associated with a 4.19-fold higher likelihood of neurogenic orthostatic hypotension (OR = 4.19; 95% CI: 1.10-15.90; p = 0.031). Conclusions: The presence of ≥ 3 abnormal Ewing tests serves as a critical indicator strongly associated with neurogenic orthostatic hypotension, reflecting widespread pre-ganglionic neuronal degeneration in MSA. Quantifying the severity of autonomic impairment through the Ewing test battery, coupled with orthostatic hypotension assessment, provides a highly valuable clinical tool for cardiovascular risk stratification and the establishment of early medical management strategies to optimize patient quality of life.
