Waist circumference has been shown to be a better predictor of cardiovascular risk than body mass index (BMI). Our case-control study aimed to evaluate the contribution of obesity and abdominal fat ...mass to the risk of stroke and transient ischemic attacks (TIA).
We recruited 1137 participants: 379 cases with stroke/TIA and 758 regional controls matched for age and sex. Associations between different markers of obesity (BMI, waist-to-hip ratio, waist circumference and waist-to-stature ratio) and risk of stroke/TIA were assessed by using conditional logistic regression adjusted for other risk factors.
BMI showed a positive association with cerebrovascular risk which became nonsignificant after adjustment for physical inactivity, smoking, hypertension, and diabetes (odds ratio 1.18; 95% CI, 0.77 to 1.79, top tertile versus bottom tertile). Markers of abdominal adiposity were strongly associated with the risk of stroke/TIA. For the waist-to-hip ratio, adjusted odds ratios for every successive tertile were greater than that of the previous one (2nd tertile: 2.78, 1.57 to 4.91; 3rd tertile: 7.69, 4.53 to 13.03). Significant associations with the risk of stroke/TIA were also found for waist circumference and waist-to-stature ratio (odds ratio 4.25, 2.65 to 6.84 and odds ratio 4.67, 2.82 to 7.73, top versus bottom tertile after risk adjustment, respectively).
Markers of abdominal adiposity showed a graded and significant association with risk of stroke/TIA, independent of other vascular risk factors. Waist circumference and related ratios can better predict cerebrovascular events than BMI.
Diffusion-weighted MRI (DWI) and perfusion MRI (PI) have been mainly applied in acute stroke, but may provide information in the peri-ictal phase in epilepsy patients. Both transient reductions of ...brain water diffusion, namely a low apparent diffusion coefficient (ADC), and signs of hyperperfusion have been reported in experimental and human epilepsy case studies. We studied 10 patients with complex partial status epilepticus (CPSE) with serial MRI including DWI and PI. All patients showed regional hyperintensity on DWI, and a reduction of the ADC in (i) the hippocampal formation and the pulvinar region of the thalamus (six out of 10 patients), (ii) the pulvinar and cortical regions (two out of 10), (iii) the hippocampal formation only (one out of 10), and (iv) the hippocampal formation, the pulvinar and the cortex (one out of 10). In all patients a close spatial correlation of focal hyperperfusion with areas of ADC/DWI change was present. In two patients hyperperfusion was confirmed in additional SPECT (single photon emission computed tomography) studies. All patients received follow-up MRI examinations showing partial or complete resolution of diffusion and perfusion abnormalities depending on the length of the follow-up interval. The clinical course, EEG and SPECT results all indicate that MRI detected changes related to prolonged epileptic activity. Combined PI and DWI can visualize haemodynamic and tissue changes after CPSE in the hippocampus, thalamus and affected cortical regions.
The costs of acute stroke care, length of hospital stay (LOS), and outcome in patients with cardioembolic stroke or cardioembolic transient ischemic attacks (TIA) were investigated with the aim of ...estimating the clinical and health-economic impacts of cerebral cardioembolism. The study population consisted of 511 consecutive patients with the diagnosis of ischemic stroke (
n
= 379) or TIA (
n
= 132) treated at the Department of Neurology, Philipps University, Marburg. Cerebral cardioembolism was defined according to the criteria of the Cerebral Embolism Task Force. Clinical status was assessed by means of Barthel index (BI) and modified Rankin Scale. Costs were calculated using a bottom-up approach. All costs (in Euros) were inflated to the 2008 level. Compared to non-cardioembolic stroke (
n
= 278) patients, patients who had suffered cardioembolic stroke (
n
= 101) had more severe clinical deficits on admission (BI 46.3 ± 27.0 vs. 59.3 ± 34.1;
P
< 0.01), worse recovery (BI on discharge 59.2 ± 28.9 vs. 73.1 ± 33.4;
P
< 0.01), and increased LOS (12.6 ± 5.7 vs. 10.0 ± 7.8 days;
P
< 0.01). The latter also required a relatively higher daily resource utilization due to increased expenses for personnel and diagnostics. Mean costs of acute care for patients with cardioembolic stroke € 4890 per patient (95% confidence interval 4460–5200) were significantly higher than those for patients with non-cardioembolic stroke € 3550 (95% confidence interval 3250–3850);
P
< 0.01. The clinical and health-economic impact of cardiogenic cerebral embolism on stroke care is considerable. Patients with cardioembolic stroke/TIA are more severely impaired, and they require longer hospital treatment and increased resource utilization. Costs of acute care of cardioembolic stroke/TIA patients may exceed those of non-cardioembolic stroke/TIA by up to 40%.
In recent years, several studies have unequivocally shown the occurrence of cortical spreading depressions (CSDs) after stroke and traumatic brain injury (TBI) in humans. The fundamental question, ...however, is whether CSDs cause or result from secondary brain damage. The aim of the current study was, therefore, to investigate the role of CSDs for secondary brain damage in an experimental model of TBI. C57/BL6 mice were traumatized by controlled cortical impact. Immediately after trauma, each animal showed one heterogeneous direct current (DC) potential shift accompanied by a profound depression of electroencephalogram (EEG) amplitude, and a temporary decrease of ipsi- and contralateral regional cerebral blood flow (rCBF) suggesting bilateral CSDs. Within the next 3 h after TBI, CSDs occurred at a low frequency (0.38 CSD/h per animal, n = 7) and were accompanied by rCBF changes confined to the ipsilateral hemisphere. No significant relationship between the number of SDs and lesion size or intracranial pressure (ICP) could be detected. Even increasing the number of posttraumatic CSDs by application of KCl by more than six times did not increase ICP or contusion volume. We therefore conclude that CSDs may not contribute to posttraumatic secondary brain damage in the normally perfused and oxygenated brain.
In barbiturate-anesthetized rats, we induced 3 hours of permanent middle cerebral artery occlusion (MCAO) by an intraluminal thread (n = 6), or 1 hour MCAO followed by 2 hours of reperfusion (n = 6). ...Through a closed cranial window over the parietal cortex, the production of reactive oxygen species (ROS) was measured in the infarct border using online in vivo chemiluminescence (CL) while monitoring the appearance of peri-infarct depolarizations (PID). The borderzone localization of the ROS and direct current (DC) potential measurements was confirmed in additional experiments using laser-Doppler scanning, mapping regional CBF changes through the cranial window after permanent (n = 5) or reversible (n = 5) MCAO. CL measurements revealed a short period (10 to 30 minutes) of reduced ROS formation after vessel occlusion, followed by a significant increase (to 162 +/- 51%; baseline = 100%; P < .05) from 100 minutes of permanent MCAO onward. Reperfusion after a 1-hour period of MCAO led to a burst-like pattern of ROS production (peak: 489 +/- 330%; P < .05). When the experiments were terminated 3 hours after induction of MCAO, CL was still significantly increased above baseline after permanent and reversible MCAO (to 190 +/- 67% and 211 +/- 64%, respectively; P < .05). Simultaneous DC potential recordings detected 6.4 +/- 2.7 PID in the first, 4.7 +/- 2.3 in the second, and 2.8 +/- 2.0 in the third hour after permanent MCAO. In animals with reversible MCAO, PID were abolished from 15-minutes recirculation onward. There was no temporal relationship between ROS production and peri-infarct DC potential shifts. In conclusion, using a high temporal resolution ROS detection technique (CL), we found that permanent MCAO (after an initial decrease) was accompanied by a steady increase of ROS production during the 3-hour observation period, while reperfusion after 1 hour of MCAO produced a burst in ROS formation. Both patterns of ROS production were not related to the occurrence of PID.
We investigated the combined effect of increased brain topical K+ concentration and reduction of the nitric oxide (NO.) level caused by nitric oxide scavenging or nitric oxide synthase (NOS) ...inhibition on regional cerebral blood flow and subarachnoid direct current (DC) potential. Using thiopental-anesthetized male Wistar rats with a closed cranial window preparation, brain topical superfusion of a combination of the NO. scavenger hemoglobin (Hb; 2 mmol/L) and increased K+ concentration in the artificial cerebrospinal fluid (K+ACSF) at 35 mmol/L led to sudden spontaneous transient ischemic events with a decrease of CBF to 14+/-7% (n=4) compared with the baseline (100%). The ischemic events lasted for 53+/-17 minutes and were associated with a negative subarachnoid DC shift of -7.3+/-0.6 mV of 49+/-12 minutes' duration. The combination of the NOS inhibitor N-nitro-L-arginine (L-NA, 1 mmol/L) with K+ACSF at 35 mmol/L caused similar spontaneous transient ischemic events in 13 rats. When cortical spreading depression was induced by KCl at a 5-mm distance, a typical cortical spreading hyperemia (CSH) and negative DC shift were measured at the closed cranial window during brain topical superfusion with either physiologic artificial CSF (n=5), or artificial CSF containing increased K+ACSF at 20 mmol/L (n=4), K+ACSF at 3 mmol/L combined with L-NA (n=10), K+ACSF at 10 mmol/L combined with L-NA (five of six animals) or K+ACSF at 3 mmol/L combined with Hb (three of four animals). Cortical spreading depression induced longlasting transient ischemia instead of CSH, when brain was superfused with either K+ACSF at 20 mmol/L combined with Hb (CBF decrease to 20+/-20% duration 25+/-21 minutes, n=4), or K+ACSF at 20 mmol/L combined with L-NA (n=19). Transient ischemia induced by NOS inhibition and K,ACSF at 20 mmol/L propagated at a speed of 3.4+/-0.6 mm/min, indicating cortical spreading ischemia (CSI). Although CSH did not change oxygen free radical production, as measured on-line by in vivo lucigenin-enhanced chemiluminescence, CSI resulted in the typical radical production pattern of ischemia and reperfusion suggestive of brain damage (n=4). Nimodipine (2 microg/kg body weight/min intravenously) transformed CSI back to CSH (n=4). Vehicle had no effect on CSI (n=4). Our data suggest that the combination of decreased NO. levels and increased subarachnoid K+ levels induces spreading depression with acute ischemic CBF response. Thus, a disturbed coupling of metabolism and CBF can cause ischemia. We speculate that CSI may be related to delayed ischemic deficits after subarachnoid hemorrhage, a clinical condition in which the release of Hb and K+ from erythrocytes creates a microenvironment similar to the one investigated here.
Lyme borreliosis-associated diseases belong to the most frequent disorders in Europe that are transmitted by tick bites (ixodes ricinus). In addition to local inflammatory reactions, B. burgdorferi ...infections can also affect the central nervous system and cause strokes by neuroborreliosis-associated cerebral vasculitis. Criteria for the diagnosis are discussed and clinical cases are presented. Very likely, this disorder remains undetected in many cases because lumbar puncture is needed for diagnosis. With rapid antibiotic treatment vasculitic changes can be reversed and outcome is commonly good. However, if the basilar artery is affected by the vasculitis, outcome may be poor. In young patients presenting with repetitive ischemic episodes of the vertebrobasilar circulation and lacking vascular risk factors, Lyme neuroborreliosis-associated vasculitis should be ruled out.
This study was undertaken to test whether transient depolarizations occurring in periinfarct regions are important in contributing to infarct spread and maturation. Following middle cerebral artery ...(MCA) occlusion we stimulated the ischemic penumbra with recurrent waves of spreading depression (SD) and correlated the histopathological changes with the electrophysiological recordings. Halothane-anesthetized, artificially ventilated Sprague-Dawley rats underwent repetitive stimulation of SD in intact brain (Group 1; n = 8) or photothrombotic MCA occlusion coupled with ipsilateral common carotid artery occlusion (Groups 2 and 3, n = 9 each). The electroencephalogram and direct current (DC) potential were recorded for 3 h in the parietal cortex, which represented the periinffarct border zone in ischemic rats. In Group 2, only spontaneously occurring negative DC shifts occurred; in Group 3, the (nonischemic) frontal pole of the ischemic hemisphere was electrically stimulated to increase the frequency of periinfarct DC shifts. Animals underwent perfusion-fixation 24 h later, and volumes of complete infarction and scattered neuronal injury ("incomplete infarction") were assessed on stained coronal sections by quantitative planimetry. Electrical induction of SD in Group 1 did not cause morphological injury. During the initial 3 h following MCA occlusion, the number of spontaneous periinfarct depolarization in Group 2 (7.0 +/- 1.5 DC shifts) was doubled in Group 3 by frontal current application (13.4 +/- 2.7 DC shifts; p < 0.001). The duration as well as the integrated negative amplitude of DC shifts over time were significantly greater in Group 3 than in Group 2 rats (duration, 5.7 +/- 3.8 vs. 4.1 +/- 2.5 min; p < 0.05). Histopathological examination disclosed well-defined areas of pannecrosis surrounded by a cortical rim exhibiting selectively damaged acidophilic neurons and astrocytic swelling in otherwise normal-appearing brain. Induction of SD in the ischemic hemisphere led to a significant increase in the volume of incomplete infarction (19.0 +/- 6.1 mm3 in Group 3 vs. 10.3 +/- 5.1 mm3 in Group 2; p < 0.01) and of total ischemic injury (100.7 +/- 41.0 mm3 in Group 3 vs. 66.5 +/- 24.7 mm3 in Group 2; p < 0.05). The integrated magnitude of DC negativity per experiment correlated significantly with the volume of total ischemic injury (r = 0.780, p < 0.0001). Thus, induction of SD in the ischemic hemisphere accentuated the development of scattered neuronal injury and increased the volume of total ischemic injury. This observation may be explained by the fact that with limited perfusion reserve, periinfarct depolarization are associated with episodic energy failure in the acute ischemic penumbra.
Glial fibrillary acidic protein (GFAP) is a biomarker candidate indicative of intracerebral hemorrhage (ICH) in patients with symptoms of acute stroke. GFAP is released rapidly in the presence of ...expanding intracerebral bleeding, whereas a more gradual release occurs in ischemic stroke. In this study the diagnostic accuracy of plasma GFAP was determined in a prospective multicenter approach.
Within a 1-year recruitment period, patients suspected of having acute (symptom onset<4.5 h before admission) hemispheric stroke were prospectively included into the study in 14 stroke centers in Germany and Switzerland. A blood sample was collected at admission, and plasma GFAP was measured by use of an electrochemiluminometric immunoassay. The final diagnosis, established at hospital discharge, was classified as ICH, ischemic stroke, or stroke mimic.
The study included 205 patients (39 ICH, 163 ischemic stroke, 3 stroke mimic). GFAP concentrations were increased in patients with ICH compared with patients with ischemic stroke median (interquartile range) 1.91 μg/L (0.41-17.66) vs 0.08 μg/L (0.02-0.14), P<0.001. Diagnostic accuracy of GFAP for differentiating ICH from ischemic stroke and stroke mimic was high area under the curve 0.915 (95% CI 0.847-0.982), P<0.001. A GFAP cutoff of 0.29 μg/L provided diagnostic sensitivity of 84.2% and diagnostic specificity of 96.3% for differentiating ICH from ischemic stroke and stroke mimic.
Plasma GFAP analysis performed within 4.5 h of symptom onset can differentiate ICH and ischemic stroke. Studies are needed to evaluate a GFAP point-of-care system that may help optimize the prehospital triage and management of patients with symptoms of acute stroke.
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