EAN/ERS/ESO/ESRS statement on the impact of sleep disorders on risk and outcome of stroke.

BACKGROUND: Sleep disorders are highly prevalent in the general population and may be linked in a bidirectional fashion to stroke, which is one of the leading causes of morbidity and mortality. AIM: Four major scientific societies established a task force of experts in neurology, stroke, respiratory medicine, sleep medicine and methodology to critically evaluate the evidence regarding potential links and the impact of therapy. MATERIALS AND METHODS: Thirteen research questions were evaluated in a systematic literature search using a stepwise hierarchical approach: first, systematic reviews and meta-analyses; second, primary studies post-dating the systematic reviews/meta-analyses. A total of 445 studies were evaluated and 88 were included. Statements were generated regarding current evidence and clinical practice. RESULTS: Severe obstructive sleep apnoea (OSA) doubles the risk for incident stroke, especially in young to middle-aged patients. Continuous positive airway pressure (CPAP) may reduce stroke risk, especially in treatment-compliant patients. The prevalence of OSA is high in stroke patients and can be assessed by polygraphy. Severe OSA is a risk factor for recurrence of stroke and may be associated with stroke mortality, whilst CPAP may improve stroke outcome. It is not clear if insomnia increases stroke risk, whilst the pharmacotherapy of insomnia may increase it. Periodic limb movements in sleep (PLMS), but not restless limb syndrome (RLS), may be associated with an increased risk of stroke. Preliminary data suggest a high frequency of post-stroke insomnia and RLS and their association with a less favourable stroke outcome, whilst treatment data are scarce. DISCUSSION/CONCLUSION: Overall, the evidence base is best for OSA relationship with stroke and supports active diagnosis and therapy. Research gaps remain especially regarding insomnia and RLS/PLMS relationships with stroke.

[Frequency and risk factors associated with post-stroke dementia-an observational study on stroke patients without premorbid cognitive impairment]. / Häufigkeit und Risikofaktoren der Post-Stroke-Demenz ­ eine Beobachtungsstudie zu Schlaganfallpatienten ohne vorbestehende kognitive Defizite.

BACKGROUND: Longitudinal studies on cognitive outcomes after stroke revealed heterogeneous results and the underlying pathology and risk factors for so-called post-stroke dementia are unclear. OBJECTIVE: To assess long-term cognitive performance changes in patients after the first ischemic stroke and to evaluate possible risk factors for post-stroke dementia. MATERIAL AND METHODS: In this study 66 clinically mildly affected patients aged 54-87 years without a history of dementia underwent extensive neuropsychological assessment after first ever ischemic stroke and again 6 months after the event (follow-up assessment). Demographic, clinical and paraclinical parameters were assessed as potential predictors for long-term cognitive outcome. RESULTS: At the group level significant performance improvements were found for most of the neurocognitive domains at the follow-up assessment. The greatest cognitive improvement was found in visuospatial processing. Immediately after stroke 54.5% of patients were considered cognitively impaired (z-scores < -2 in at least 2 neurocognitive domains). At follow-up only 16.7% were considered cognitively impaired according to this criterion and among these only 2 patients (3%) had developed a new, clinically relevant cognitive impairment (i.e. post-stroke dementia). Patients with inferior cognitive performance improvements at follow-up had on average larger brain lesions caused by the stroke as well as a prediabetic metabolic status. DISCUSSION: The probability of developing a post-stroke dementia syndrome is lower than previously assumed in patients with first ever stroke, with only mild clinical disability and without premorbid cognitive impairment. Long-term cognitive impairment could primarily be determined by the size of the lesioned brain area as well as the premorbid (pre)diabetic status.

Immunophenotyping of cerebrospinal fluid cells in ischaemic stroke.

BACKGROUND AND PURPOSE: Post-ischaemic immune cell invasion into the brain is well characterized in animal stroke models and contributes to neuronal damage. Therefore, it represents a promising therapeutic target. Cerebrospinal fluid (CSF) is easily accessible and may reflect cellular events within the parenchyma. However, comprehensive studies on CSF immune cells in patients with stroke are lacking. METHODS: In a retrospective cohort study, we performed extensive immune-cell profiling in CSF and peripheral blood of patients with acute ischaemic stroke and healthy controls. In patients with stroke, infarct size was quantified on follow-up imaging. RESULTS: Overall, 90 patients with ischaemic stroke and 22 controls were included in our study. After stroke, the total protein was increased (537.3 vs. 353.2 mg/L, P = 0.008) and the mean total white cell count was slightly but non-significantly elevated (1.76 vs. 0.50 cells/µL, P = 0.059). Proportions of CSF lymphocytes, monocytes and granulocytes and their respective subsets did not differ between patients with stroke and controls. In addition, there were no associations between proportions of major leukocyte subsets in CSF and the time from symptom onset to CSF sampling, infarct size or infarct localization. CONCLUSIONS: Ischaemic stroke induces only a very slight increase of CSF immune cells without changes in the composition of immune cell subsets, thus indicating that parenchymal inflammation is not sufficiently reflected in the CSF. Our findings suggest that CSF is not a major invasion route for immune cells and that CSF cell analyses are not suitable as biomarkers to guide future immune therapies for stroke.

Thrombectomy in posterior circulation stroke: differences in procedures and outcome compared to anterior circulation stroke in the prospective multicentre REVASK registry.

BACKGROUND AND PURPOSE: In contrast to anterior circulation stroke (ACS), there is no evidence from randomized trials that mechanical thrombectomy (MT) with modern stent retrievers or thromboaspiration is safe and effective in posterior circulation stroke (PCS). METHODS: The present analysis was based on the prospective multicentre Registry on Revascularization in Ischemic Stroke Patients (REVASK) in Germany. Demographic data, periprocedural times and complications, recanalization rates, and functional outcome at discharge and after 3 months were compared between 139 consecutive patients with PCS (84.9% basilar artery, 16.5% vertebral artery and 4.3% posterior cerebral artery occlusion) and 961 patients with ACS treated with MT. RESULTS: Compared to ACS, PCS patients were significantly younger (65 vs. 69 years, P = 0.021) and had a lower median National Institutes of Health Stroke Scale (NIHSS) score at baseline (12 vs. 15, P = 0.024). Patients with PCS had a significantly longer time delay between symptom onset and both start and end of the MT procedure. Successful recanalization and thrombectomy passes did not significantly differ between the two groups. No symptomatic intracranial haemorrhage occurred in PCS compared to 3% in ACS (P = 0.010). The median NIHSS score at discharge was 3 in PCS and 4 in ACS. Favourable functional outcome at 3 months (modified Rankin Scale 0-2 38.0% vs. 42.6%, P = 0.392) and mortality (33.7% vs. 30.8%, P = 0.539) did not differ significantly between PCS and ACS. CONCLUSIONS: The study suggests that MT in PCS shows a lower risk of symptomatic intracranial haemorrhage and similar effectiveness compared to ACS. PCS patients also seem to benefit from MT started beyond 6 h after symptom onset.

Refinement of detecting atrial fibrillation in stroke patients: results from the TRACK-AF Study.

BACKGROUND AND PURPOSE: Detection of occult atrial fibrillation (AF) is crucial for optimal secondary prevention in stroke patients. The AF detection rate was determined by implantable cardiac monitor (ICM) and compared to the prediction rate of the probability of incident AF by software based analysis of a continuously monitored electrocardiogram at follow-up (stroke risk analysis, SRA); an optimized AF detection algorithm is proposed by combining both tools. METHODS: In a monocentric prospective study 105 out of 389 patients with cryptogenic stroke despite extensive diagnostic workup were investigated with two additional cardiac monitoring tools: (a) 20 months' monitoring by ICM and (b) SRA during hospitalization at the stroke unit. RESULTS: The detection rate of occult AF was 18% by ICM (n = 19) (range 6-575 days) and 62% (n = 65) had an increased risk for AF predicted by SRA. When comparing the predictive accuracy of SRA to ICM, the sensitivity was 95%, specificity 35%, positive predictive value 27% and negative predictive value 96%. In 18 patients with AF detected by ICM, SRA also showed a medium risk for AF. Only one patient with a very low risk predicted by SRA developed AF revealed by ICM after 417 days. CONCLUSIONS: A combination of SRA and ICM is a promising strategy to detect occult AF. SRA is reliable in predicting incident AF with a high negative predictive value. Thus, SRA may serve as a cost-effective pre-selection tool identifying patients at risk for AF who may benefit from further cardiac monitoring by ICM.

Impact of the Implementation of Thrombectomy with Stent Retrievers on the Frequency of Hemicraniectomy in Patients with Acute Ischemic Stroke.

BACKGROUND: The increasing use of endovascular treatments has led to higher recanalization rates and better clinical outcomes compared with intravenous thrombolysis alone. Stent retrievers represent the latest development for recanalization of large vessel occlusions. Decompressive hemicraniectomy has proved beneficial in patients suffering from rising intracranial pressure after malignant stroke. AIMS AND/OR HYPOTHESIS: We investigated the effect of the implementation of stent retriever treatment on the frequency of hemicraniectomy as a surrogate marker for infarct size and thus for poor neurological outcome. METHODS: Patients with acute ischemic stroke were retrospectively studied. We compared the frequency of hemicraniectomy following proximal artery occlusion of the internal carotid artery and middle cerebral artery main stem in the years before (2009 and 2010) and after (2012 and 2013) introducing stent retrievers. RESULTS: Overall, 497 patients with proximal arterial occlusion were included in the study. Of 253 patients admitted in the years 2009 and 2010 44 (17.4 %) and of 244 patients admitted in 2012 and 2013, 20 (8.2 %) received a hemicraniectomy. This decrease in the proportion of hemicraniectomies was statistically significant (p < 0.01). CONCLUSIONS: The findings in this study illustrate a significantly reduced rate of hemicraniectomies in patients with proximal artery occlusions after implementation of thrombectomy with stent retriever. Hereby, we could show a significant reduction of malignant infarctions after thrombectomy with stent retriever.

Effects of emergency medical service transport on acute stroke care.

BACKGROUND AND PURPOSE: Since early treatment of acute stroke is associated with an improved outcome, emergency medical service (EMS) transport of stroke patients is recommended. It remains unclear, however, whether EMS transport leads to faster treatment. The impact of the transport mode on pre- and in-hospital processes of care was therefore investigated. METHODS: The present study was based on a prospective database of 158 hospitals of the Stroke Register of Northwestern Germany, which included 162,511 stroke patients admitted between January 2010 and December 2011. Main outcome measures were the baseline characteristics associated with EMS transport and process-of-care indicators according to the transport mode. RESULTS: Overall, 101,850 (72.0%) patients were transported by EMS and 39,324 (28.0%) by self-transport. The baseline characteristics showing the strongest associations with EMS use were the care situation [institutional care, adjusted odds ratio (OR) 7.81; 95% CI 6.86-8.90], a disturbed level of consciousness (adjusted OR 3.00; 95% CI 2.59-3.48) and having a subarachnoid (adjusted OR 2.79; 95% CI 2.24-3.49) or intracerebral hemorrhage (adjusted OR 2.26; 95% CI 1.92-2.67). For self-transport patients the probability of being in a higher onset-to-door time category was 4.36 (95% CI 4.26-4.47) and the probability of being in a higher door-to-imaging time category was 1.32 (95% CI 1.28-1.36). Compared with self-transport, EMS transport was independently associated with thrombolysis (adjusted OR 1.95, 95% CI 1.77-2.15). CONCLUSIONS: Patient transport with EMS was independently associated with faster hospital arrival and shorter time periods from hospital admission to brain imaging and to the frequency of thrombolysis.

Serum C-reactive protein is linked to cerebral microstructural integrity and cognitive function.

OBJECTIVE: C-reactive protein is a marker of inflammation and vascular disease. It also seems to be associated with an increased risk of dementia. To better understand potential underlying mechanisms, we assessed microstructural brain integrity and cognitive performance relative to serum levels of high-sensitivity C-reactive protein (hs-CRP). METHODS: We cross-sectionally examined 447 community-dwelling and stroke-free individuals from the Systematic Evaluation and Alteration of Risk Factors for Cognitive Health (SEARCH) Health Study (mean age 63 years, 248 female). High-field MRI was performed in 321 of these subjects. Imaging measures included fluid-attenuated inversion recovery sequences for assessment of white matter hyperintensities, automated quantification of brain parenchyma volumes, and diffusion tensor imaging for calculation of global and regional white matter integrity, quantified by fractional anisotropy (FA). Psychometric analyses covered verbal memory, word fluency, and executive functions. RESULTS: Higher levels of hs-CRP were associated with worse performance in executive function after adjustment for age, gender, education, and cardiovascular risk factors in multiple regression analysis (beta = -0.095, p = 0.02). Moreover, higher hs-CRP was related to reduced global fractional anisotropy (beta = -0.237, p < 0.001), as well as regional FA scores of the frontal lobes (beta = -0.246, p < 0.001), the corona radiata (beta = -0.222, p < 0.001), and the corpus callosum (beta = -0.141, p = 0.016), in particular the genu (beta = -0.174, p = 0.004). We did not observe a significant association of hs-CRP with measures of white matter hyperintensities or brain atrophy. CONCLUSION: These data suggest that low-grade inflammation as assessed by high-sensitivity C-reactive protein is associated with cerebral microstructural disintegration that predominantly affects frontal pathways and corresponding executive function.