Parasympathetic activity correlates with early outcome in patients with large artery atherosclerotic stroke

To evaluate the associations between autonomic function and early stroke outcome in different subtypes of cerebral infarct, 24 patients with acute large artery atherosclerotic infarction (LAA), 26 patients with acute lacunar infarction (LAC), and 19 control subjects were prospectively recruited. Stroke outcome by the National Institute of Health Stroke Score (NIHSS) and heart rate variability (HRV) by power spectral analysis were recorded. The LAA group had lower high-frequency power (HF, P = 0.017), lower normalized HF (P = 0.002), higher normalized low-frequency power (LF%, P = 0.016), and higher ratio of LF to HF (P = 0.003) than both the LAC and control groups. Multivariate regression analysis in the LAA group showed that HF significantly correlated with early outcome (standardized coefficient = - 0.486, P = 0.016), and HF less than 3.9 [ln(ms 2)] was an independent risk factor for NIHSS ≥ 4 at seventh day after admission (odd ratio = 6.00, 95% confidence interval 1.02-35.37, P = 0.048). There was no significant correlation between any HRV parameter and early stroke outcome in the LAC group. There were different autonomic function properties between LAA and LAC groups, and depressed parasympathetic modulation was associated with worse early outcome in patients with LAA.