Higher NIHSS scores in ischemic stroke patients significantly correlated with progressive loss of autonomic modulation and baroreflex sensitivity (Spearman-Rho 0.29 to 0.47).
Observational (n=82)
Does stroke severity assessed by NIHSS correlate with autonomic dysfunction in ischemic stroke patients?
Increasing stroke severity (higher NIHSS) is associated with progressive loss of overall autonomic modulation, parasympathetic decline, and sympathetic dominance, suggesting NIHSS can predict risk of autonomic dysregulation.
Estimación del efecto: Spearman-Rho 0.29 to 0.47
BACKGROUND AND PURPOSE: Stroke is frequently associated with autonomic dysfunction, which causes secondary cardiovascular complications. Early diagnosis of autonomic imbalance prevents complications, but it is only available at specialized centers. Widely available surrogate markers are needed. This study tested whether stroke severity, as assessed by National Institutes of Health Stroke Scale (NIHSS) scores, correlates with autonomic dysfunction and thus predicts risk of autonomic complications. METHODS: In 50 ischemic stroke patients, we assessed NIHSS scores and parameters of autonomic cardiovascular modulation within 24 hours after stroke onset and compared data with that of 32 healthy controls. We correlated NIHSS scores with parameters of total autonomic modulation (total powers of R-R interval RRI modulation; RRI standard deviation RRI-SD, RRI coefficient of variation), parasympathetic modulation (square root of the mean squared differences of successive RRIs, RRI-high-frequency-powers), sympathetic modulation (normalized RRI-low-frequency-powers, blood pressure-low-frequency-powers), the index of sympatho-vagal balance (RRI-LF/HF-ratios), and baroreflex sensitivity. RESULTS: Patients had significantly higher blood pressure and respiration, but lower RRIs, RRI-SDs, RRI coefficient of variation, square root of the mean squared differences of successive RRIs, RRI-low-frequency-powers, RRI-high-frequency-powers, RRI-total powers, and baroreflex sensitivity than did controls. NIHSS scores correlated significantly with normalized RRI-low-frequency-powers and RRI-LF/HF-ratios, and indirectly with RRIs, RRI-SDs, square root of the mean squared differences of successive RRIs, RRI-high-frequency-powers, normalized RRI-high-frequency-powers, RRI-total-powers, and baroreflex sensitivity. Spearman-Rho values ranged from 0.29 to 0.47. CONCLUSIONS: Increasing stroke severity was associated with progressive loss of overall autonomic modulation, decline in parasympathetic tone, and baroreflex sensitivity, as well as progressive shift toward sympathetic dominance. All autonomic changes put patients with more severe stroke at increasing risk of cardiovascular complications and poor outcome. NIHSS scores are suited to predict risk of autonomic dysregulation and can be used as premonitory signs of autonomic failure.
Hilz et al. (Fri,) conducted a observational in Ischemic stroke (n=82). National Institutes of Health Stroke Scale (NIHSS) score vs. Healthy controls was evaluated on Correlation between NIHSS scores and parameters of autonomic cardiovascular modulation (Spearman-Rho 0.29 to 0.47). Higher NIHSS scores in ischemic stroke patients significantly correlated with progressive loss of autonomic modulation and baroreflex sensitivity (Spearman-Rho 0.29 to 0.47).