scholarly journals Dynamic functional connectivity analysis reveals transiently increased segregation in patients with severe stroke

2020 ◽  
Author(s):  
Anna K. Bonkhoff ◽  
Markus D. Schirmer ◽  
Martin Bretzner ◽  
Mark Etherton ◽  
Kathleen Donahue ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Acute Stroke ◽  
Acute Ischemic Stroke ◽  
Network Connectivity ◽  
Functional Network ◽  
Angular Gyrus ◽  
Stroke Severity ◽  
Functional Network Connectivity ◽  
Dynamic Connectivity ◽  
Dynamic Functional Network Connectivity

AbstractBackground and PurposeTo explore the whole-brain dynamic functional network connectivity patterns in acute ischemic stroke (AIS) patients and their relation to stroke severity in the short and long term.MethodsWe investigated large-scale dynamic functional network connectivity of 41 AIS patients two to five days after symptom onset. Re-occurring dynamic connectivity configurations were obtained using a sliding window approach and k-means clustering. We evaluated differences in dynamic patterns between three NIHSS-stroke severity defined groups (mildly, moderately, and severely affected patients). Furthermore, we established correlation analyses between dynamic connectivity estimates and AIS severity as well as neurological recovery within the first 90 days after stroke (DNIHSS). Finally, we built Bayesian hierarchical models to predict acute ischemic stroke severity and examine the inter-relation of dynamic connectivity and clinical measures, with an emphasis on white matter hyperintensity lesion load.ResultsWe identified three distinct dynamic connectivity configurations in the early post-acute stroke phase. More severely affected patients (NIHSS 10–21) spent significantly more time in a highly segregated dynamic connectivity configuration that was characterized by particularly strong connectivity (three-level ANOVA: p<0.05, post hoc t-tests: p<0.05, FDR-corrected for multiple comparisons). Recovery, as indexed by the realized change of the NIHSS over time, was significantly linked to the acute dynamic connectivity between bilateral intraparietal lobule and left angular gyrus (Pearson’s r = –0.68, p<0.05, FDR-corrected). Increasing dwell times, particularly those in a very segregated connectivity configuration, predicted higher acute stroke severity in our Bayesian modelling framework.ConclusionsOur findings demonstrate transiently increased segregation between multiple functional domains in case of severe AIS. Dynamic connectivity involving default mode network components significantly correlated with recovery in the first three months post-stroke.

scholarly journals Elevation of troponin I in acute ischemic stroke

PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e1866 ◽  
Author(s):  
Yu-Chin Su ◽  
Kuo-Feng Huang ◽  
Fu-Yi Yang ◽  
Shinn-Kuang Lin
Keyword(s):  
Ischemic Stroke ◽  
Hospital Mortality ◽  
Acute Stroke ◽  
Acute Ischemic Stroke ◽  
Barthel Index ◽  
Troponin I ◽  
Clinical Deterioration ◽  
Stroke Severity ◽  
Nihss Score ◽  
Poor Outcome

Background. Cardiac morbidities account for 20% of deaths after ischemic stroke and is the second commonest cause of death in acute stroke population. Elevation of cardiac troponin has been regarded as a prognostic biomarker of poor outcome in patients with acute stroke.Methods. This retrospective study enrolled 871 patients with acute ischemic stroke from August 2010 to March 2015. Data included vital signs, laboratory parameters collected in the emergency department, and clinical features during hospitalization. National Institutes of Health Stroke Scale (NIHSS), Barthel index, and modified Rankin Scale (mRS) were used to assess stroke severity and outcome.Results.Elevated troponin I (TnI) > 0.01 µg/L was observed in 146 (16.8%) patients. Comparing to patients with normal TnI, patients with elevated TnI were older (median age 77.6 years vs. 73.8 years), had higher median heart rates (80 bpm vs. 78 bpm), higher median white blood cells (8.40 vs. 7.50 1,000/m3) and creatinine levels (1.40 mg/dL vs. 1.10 mg/dL), lower median hemoglobin (13.0 g/dL vs. 13.7 g/dL) and hematocrit (39% vs. 40%) levels, higher median NIHSS scores on admission (11 vs. 4) and at discharge (8 vs. 3), higher median mRS scores (4 vs3) but lower Barthel index scores (20 vs. 75) at discharge (p< 0.001). Multivariate analysis revealed that age ≥ 76 years (OR 2.25, CI [1.59–3.18]), heart rate ≥ 82 bpm (OR 1.47, CI [1.05–2.05]), evidence of clinical deterioration (OR 9.45, CI [4.27–20.94]), NIHSS score ≥ 12 on admission (OR 19.52, CI [9.59–39.73]), and abnormal TnI (OR 1.98, CI [1.18–3.33]) were associated with poor outcome. Significant factors for in-hospital mortality included male gender (OR 3.69, CI [1.45–9.44]), evidence of clinical deterioration (OR 10.78, CI [4.59–25.33]), NIHSS score ≥ 12 on admission (OR 8.08, CI [3.04–21.48]), and elevated TnI level (OR 5.59, CI [2.36–13.27]).C-statistics revealed that abnormal TnI improved the predictive power of both poor outcome and in-hospital mortality. Addition of TnI > 0.01 ug/L or TnI > 0.1 ug/L to the model-fitting significantly improvedc-statistics for in-hospital mortality from 0.887 to 0.926 (p= 0.019) and 0.927 (p= 0.028), respectively.Discussion.Elevation of TnI during acute stroke is a strong independent predictor for both poor outcome and in-hospital mortality. Careful investigation of possible concomitant cardiac disorders is warranted for patients with abnormal troponin levels.

scholarly journals Evaluating the Role of Oxidative Stress in Acute Ischemic Stroke

2020 ◽  
Vol 11 (01) ◽  
pp. 156-159
Author(s):  
Bindu Menon ◽  
Krishnan Ramalingam ◽  
Rajeev Kumar
Keyword(s):  
Oxidative Stress ◽  
Ischemic Stroke ◽  
Acute Stroke ◽  
Acute Ischemic Stroke ◽  
Lipid Membranes ◽  
Demographic Data ◽  
Stroke Severity ◽  
Stroke Patients ◽  
Antioxidant Power

Abstract Background The role of oxidative stress in neuronal injury due to ischemic stroke has been an interesting topic in stroke research. Malondialdehyde (MDA) has emerged as a sensitive oxidative stress biomarker owing to its ability to react with the lipid membranes. Total antioxidant power (TAP) is another biomarker to estimate the total oxidative stress in stroke patients. We aimed to determine the oxidative stress in acute stroke patients by measuring MDA and TAP. Materials and Methods MDA and TAP were determined in 100 patients with ischemic stroke and compared with that in 100 age- and sex-matched healthy adults. Demographic data, stroke severity measured by the National Institutes of Health Stroke Scale (NIHSS), and disability measured by the Barthel index (BI) were recorded. The association of MDA and TAP with other variables was analyzed by paired t-test. Results Of the whole sample, 74% represented males. The mean NIHSS score was 13.11 and BI was 38.87. MDA was significantly higher in stroke patients (7.11 ± 1.67) than in controls (1.64 ± 0.82; p = 0.00). TAP was significantly lower in stroke patients (5.72 ± 1.41) than in controls (8.53 ± 2.4; p = 0.00). The lipid profile and blood sugar levels were also significantly higher in stroke patients. There was no association of MDA and TAP with other variables. Conclusion We found that oxidative stress was associated with acute ischemic stroke. However, we could not establish an association between oxidative stress and the severity of acute stroke.

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