Difficulties in the prehospital assessment of patients with TIA/stroke

BACKGROUND

In patients with TIA/stroke, early assessment is critical.

AIM

To describe patients who were not directly transported to hospital by ambulance after prehospital assessment.

METHODS

Patients hospitalized with TIA/stroke in Gothenburg, Data were obtained from the EMS and hospital case record system.

RESULTS

There were 7,812 patients with TIA/stroke, of which 4,853 (62%) were candidates for EMS transport. Among them, 176 (3.6%) were not directly transported to hospital by ambulance. In 45% of them, delay from symptom onset to calling for EMS was ≤24 hours. On EMS arrival, common symptom was dizziness (28%), followed by weakness in arm or leg (21%), loss of sensibility (13%), speech disturbances (7%), and facial numbness (4%). The modified National Institute of Health Stroke Score (mNIHSS) was 0 in 80% and >1 in two per cent. The NIHSS at the emergency department was 1-4 in 39% and 5-15 in six per cent. The EMS clinician made the decision not to transport the patient to hospital by the EMS in 84%, the dispatcher in 12% and the patient or relatives in four per cent. Patients were involved in the decision in 51%. Final diagnosis was stroke in 74% and the proportion who were independent in normal daily activities at hospital discharge decreased by 15% compared with before event.

CONCLUSION

About 3%-4% of patients with TIA/stroke were not directly transported to hospital by EMS after prehospital assessment. The most common symptom was dizziness. Decision-support tools for EMS to identify time-sensitive conditions are required.

Do patients with large vessel occlusion ischemic stroke harboring prestroke disability benefit from thrombectomy?

OBJECTIVES

Evidence of endovascular treatment (EVT) for acute large vessel occlusion (LVO) ischemic stroke in patients harboring substantial prestroke disability is lacking due to their exclusion from randomized trials. Here, we used routine care observational data to compare outcomes in patients with and without prestroke disability receiving EVT for LVO ischemic stroke.

METHODS

Consecutive patients undergoing EVT for acute LVO ischemic stroke at the Sahlgrenska University Hospital from January 1st, 2015 to March 31st, 2018 were registered in the Sahlgrenska Stroke Recanalization Registry. Pre- and poststroke functional levels were assessed by the modified Rankin Scale (mRS). Outcomes were recanalization rate (mTICI = 2b/3), symptomatic intracranial hemorrhage [sICH], complications during hospital stay, and return to prestroke functional level and mortality at 3 months.

RESULTS

Among 591 patients, 90 had prestroke disability (mRS ≥ 3). The latter group were older, more often female, had more comorbidities and higher NIHSS scores before intervention compared to patients without prestroke disability. Recanalization rates (80.0% vs 85.0%, p = 0.211), sICH (2.2% vs 6.3% p = 0.086) and the proportion of patients returning to prestroke functional level (22.7% vs 14.8% p = 0.062) did not significantly differ between those with and without prestroke disability. Patients with prestroke disability had higher complication rates during hospital stay (55.2% vs 40.1% p < 0.01) and mortality at 3 months (48.9% vs 24.3% p < 0.001).

CONCLUSION

One of five with prestroke disability treated with thrombectomy for a LVO ischemic stroke returned to their prestroke functional level. However, compared to patients without prestroke disability, mortality at 3 months was higher.

Acute symptomatic seizures and epilepsy after mechanical thrombectomy

PURPOSE

The purpose of this study was to assess the incidence of acute symptomatic seizures and poststroke epilepsy (PSE) in a well-characterized cohort of patients treated with mechanical thrombectomy. In addition, we aimed to describe the dynamics of blood markers of brain injury in patients that developed PSE.

METHODS

Participants of the prospective AnStroke Trial of anesthesia method during mechanical thrombectomy were included and acute symptomatic seizures and PSE ascertained by medical records review. Blood markers neurofilament light (NFL), tau, glial fibrillary acidic protein (GFAP), S100 calcium-binding protein B (S100B), and neuron-specific enolase (NSE) were assessed.

RESULTS

A total of 90 patients with acute anterior ischemic stroke were included. Median National Institutes of Health Stroke Scale (NIHSS) at admission to hospital was 18 (IQR 15-22). Recanalization was achieved in 90%. No patients had epilepsy prior to the ischemic stroke. Four patients (4.4%) had acute symptomatic seizures and four patients (4.4%) developed PSE during the follow-up time (to death or last medical records review) of 0-4.5 years (median follow-up 1070 days IQR 777-1306), resulting in a two-year estimated PSE risk of 5.3% (95%CI: 0.2-10.4%). Blood markers of brain injury (NFL, tau, GFAP, S100B, and NSE) were generally above the cohort median in patients that developed PSE.

CONCLUSIONS

The incidence of PSE after mechanical thrombectomy was low in our cohort. All blood biomarkers displayed interesting sensitivity and specificity. However, the number of PSE cases was small and more studies are needed on risk factors for PSE after mechanical thrombectomy. The potential of blood markers of brain injury markers to contribute to assessment of PSE risk should be explored further. This article is part of the Special Issue "Seizures & Stroke".

Cerebrospinal fluid biomarkers in patients with neurological symptoms but without neurological diseases

BACKGROUND

Elevated levels of the cerebrospinal fluid (CSF) neuronal injury markers (neurofilament light chain [NF-L] and total tau protein [t-tau]) and of the astroglial marker glial fibrillary acidic protein (GFAP) are found in etiologically different neurological disorders affecting the peripheral and the central nervous system.

AIMS

To explore the role of CSF biomarkers in the clinical management of patients admitted for alarming neurological symptoms, but in whom neurological disorders could be excluded.

METHODS

Study participants were patients seeking medical attention for neurological symptoms primarily considered to be caused by a neurological diagnosis and investigated according to clinical routine. Demographic, clinical, and CSF data were extracted retrospectively from medical records. Patients with a final neurological diagnosis were excluded.

RESULTS

Out of 990 patients, 900 with a neurological diagnosis were excluded leaving 90 patients without a final neurological diagnosis. Sixty-eight (75.6%) were females. Median (range) age at lumbar puncture was 34.7 (16.9-65.1) years. Age-adjusted CSF-NF-L, CSF-t-tau, and CSF-GFAP concentrations were normal in 89 (98.9%), 86 (95.6%), and 87 (96.7%) patients, respectively.

CONCLUSION

In patients with significant neurological symptoms but in whom a neurological diagnosis could not be made, the CSF markers NF-L, t-tau, and GFAP did not indicate signs of neuronal or astroglial cell damage close to symptom onset. Consequently, increased levels of CSF markers are not expected in this patient group and, if present, should raise suspicion of underlying neurological disorders and motivate further investigations.

Circulating neurofilament light in ischemic stroke: temporal profile and outcome prediction

Background and purpose

Neurofilament light chain (NfL) is a marker of neuroaxonal damage. We aimed to study associations between serum NfL (sNfL) concentrations at different time points after ischemic stroke and outcomes.

Methods

We prospectively included ischemic stroke cases (n = 595, mean age 59 years, 64% males) and assessed outcomes by both the modified Rankin Scale (mRS) and the NIH stroke scale (NIHSS) at 3 months and by mRS at 2 years. In a subsample, long-term (7-year) outcomes were also assessed by both mRS and NIHSS. We used the ultrasensitive single-molecule array assay to measure sNfL in the acute phase (range 1–14, median 4 days), after 3 months and 7 years in cases and once in controls (n = 595).

Results

Acute-phase sNfL increased by the time to blood-draw and highest concentrations were observed at 3 months post-stroke. High sNfL associated to stroke severity and poor outcomes, and both associations were strongest for 3-month sNfL. After adjusting for age, previous stroke, stroke severity, and day of blood draw, 3-month sNfL was significantly associated to both outcomes at all time points (p < 0.01 throughout). For all main etiological subtypes, both acute phase and 3-month sNfL were significantly higher than in controls, but the dynamics of sNfL differed by stroke subtype.

Conclusions

The results from this study inform on sNfL in ischemic stroke and subtypes over time, and show that sNfL predicts short- and long-term neurological and functional outcomes. Our findings suggest a potential utility of sNfL in ischemic stroke outcome prediction.

Electronic supplementary material

The online version of this article (10.1007/s00415-019-09477-9) contains supplementary material, which is available to authorized users.

Cerebrospinal fluid neurofilament light and tau protein as mortality biomarkers in parkinsonism

BACKGROUND

Mortality is increased in parkinsonian disorders, moderately in Parkinson's disease (PD) but markedly in atypical parkinsonian disorders (APD), including multiple system atrophy (MSA), progressive supranuclear palsy (PSP), and corticobasal degeneration (CBD). Still, there are no reliable quantitative biomarkers for mortality. The cerebrospinal fluid (CSF) neurodegeneration biomarkers such as neurofilament light chain (NF-L), total tau (t-tau), and the tau pathology marker phosphorylated tau (p-tau) are related to mortality in other neurological disorders (eg, amyotrophic lateral sclerosis, Alzheimer's disease), but have not been investigated in this respect in parkinsonian disorders.

AIMS

To investigate the CSF biomarkers' (NF-L, t-tau, and p-tau) relationship to mortality in parkinsonian disorders.

METHODS

Demographic, mortality, and CSF data were collected from 68 PD and 83 APD patients. Survival analysis was conducted using Cox regression, with age at lumbar puncture, gender, diagnosis, and levels of CSF biomarkers as predictors.

RESULTS

NF-L in CSF was associated with increased mortality in synucleinopathies (PD, MSA; HR 3.698 [2.196-6.228, 95% confidence interval (CI)], P < 0.001), in PSP (HR 2.767 [1.126-6.802 95% CI], P = 0.027), and in the entire cohort (HR 1.661 [1.082-2.55, 95% CI], P = 0.02). t-Tau in CSF was associated with increased mortality in PSP (HR 9.587 [1.143-80.418], P = 0.037). p-Tau in CSF was associated with decreased mortality in synucleinopathies (HR 0.196 [0.041-0.929, 95% CI], P = 0.040). Atypical parkinsonian disorders and tauopathies were associated with higher mortality (HR 8.798 [4.516-17.14, 95% CI] and HR 3.040 [1.904-4.854], respectively, P < 0.001).

CONCLUSION

NF-L and tau protein in CSF might be useful for mortality prognosis in patients with parkinsonian disorders and should be investigated in larger studies.

Interrupted transport by the emergency medical service in stroke/transitory ischemic attack: A consequence of changed treatment routines in prehospital emergency care

BACKGROUND

The discovery that not all patients who call for the emergency medical service (EMS) require transport to hospital has changed the structure of prehospital emergency care. Today, the EMS clinician at the scene already distinguishes patients with a time-critical condition such as stroke/transitory ischemic attack (TIA) from patients without. This highlights the importance of the early identification of stroke/TIA.

AIM

To describe patients with a final diagnosis of stroke/TIA whose transport to hospital was interrupted either due to a lack of suspicion of the disease by the EMS crew or due to refusal by the patient or a relative/friend.

METHODS

Data were obtained from a register in Gothenburg, covering patients hospitalised due to a final diagnosis of stroke/TIA. The inclusion criterion was that patients were assessed by the EMS but were not directly transported to hospital by the EMS.

RESULTS

Among all the patients who were assessed by the EMS nurse and subsequently diagnosed with stroke or TIA in 2015, the transport of 34 of 1,310 patients (2.6%) was interrupted. Twenty-five of these patients, of whom 20 had a stroke and five had a TIA, are described in terms of initial symptoms and outcome. The majority had residual symptoms at discharge from hospital. Initial symptoms were vertigo/disturbed balance in 11 of 25 cases. Another three had symptoms perceived as a change in personality and three had a headache.

CONCLUSION

From this pilot study, we hypothesise that a fraction of patients with stroke/TIA who call for the EMS have their direct transport to hospital interrupted due to a lack of suspicion of the disease by the EMS nurse at the scene. These patients appear to have more vague symptoms including vertigo and disturbed balance. Instruments to identify these patients at the scene are warranted.

Evaluation of the Swedish National Stroke Campaign: A population-based time-series study

BACKGROUND

Time delay from stroke onset to hospital arrival is an important obstacle to recanalization therapy. To increase knowledge about stroke symptoms and potentially reduce delayed hospital arrival, a 27-month national public information campaign was conducted in Sweden.

AIM

To assess the effects of a national stroke campaign in Sweden.

METHODS

This nationwide study included 97,840 patients with acute stroke, admitted to hospital and registered in the Swedish Stroke Register from 1 October 2010 to 31 December 2014 (one year before the campaign started to one year after the campaign ended). End points were (1) proportion of patients arriving at hospital within 3 h of stroke onset and (2) the proportion < 80 years of age receiving recanalization therapy.

RESULTS

During the campaign, both the proportion of patients arriving at hospital within 3 h (p < 0.05) and the proportion receiving recanalization therapy (p < 0.001) increased. These proportions remained stable the year after the campaign, and no significant improvements with respect to the two end points were observed during the year preceding the campaign. In a multivariable logistic regression model comparing the last year of the campaign with the year preceding the campaign, the odds ratio of arriving at hospital within 3 h was 1.05 (95% confidence interval (CI): 1.00-1.09) and that of receiving recanalization was 1.34 (95% CI: 1.24-1.46).

CONCLUSION

The Swedish National Stroke Campaign was associated with a sustained increase in the proportion of patients receiving recanalization therapy and a small but significant improvement in the proportion arriving at hospital within 3 h.

Off-hour admission and impact on neurological outcome in endovascular treatment for acute ischemic stroke

BACKGROUND AND PURPOSE

In the new era of endovascular treatment for acute ischemic stroke, one of the main predictors of good neurological outcome is a short time interval from stroke onset to recanalization of the occluded vessel. In this study, we examined the effect of on-hour vs off-hour admittance on the time intervals from stroke onset to recanalization in patients with acute ischemic stroke (AIS) undergoing endovascular treatment (EVT).

METHODS

One-hundred-ninety-eight patients receiving EVT for anterior AIS between 2007 and 2016 were included. Time of day and weekday for stroke admittance were recorded as well as several time intervals. Age, sex, co-morbidities, admission National Institutes of Health Stroke Scale (NIHSS), intraprocedural blood pressure, blood glucose, modified Thrombolysis in Cerebral Ischemia score (mTICI) and neurological outcome at 3 months, measured as modified Rankin Scale (mRS), were registered. On-hour was defined as 8 am-4 pm weekdays, and off-hour as weekdays outside these hours and weekends.

RESULTS

The time interval from CT (computed tomography) to recanalization was longer during off-hours, while no difference was seen in the time interval from stroke onset to CT. No statistically significant difference was seen in neurological outcome between the on- and off-hour groups in a univariate analysis.

CONCLUSIONS

Stroke admittance during off-hours is associated with longer time interval from CT examination to vessel recanalization. The study highlights the need of logistic improvement and probably more resources off-hour in order to deliver an effective stroke care around the clock.

Transient increase in CSF GAP-43 concentration after ischemic stroke

BACKGROUND

Cerebrospinal fluid (CSF) biomarkers reflect ongoing processes in the brain. Growth-associated protein 43 (GAP-43) is highly upregulated in brain tissue shortly after experimental ischemia suggesting the CSF GAP-43 concentration may be altered in ischemic brain disorders. CSF GAP-43 concentration is elevated in Alzheimer's disease patients; however, patients suffering from stroke have not been studied previously.

METHODS

The concentration of GAP-43 was measured in longitudinal CSF samples from 28 stroke patients prospectively collected on days 0-1, 2-4, 7-9, 3 weeks, and 3-5 months after ischemia and cross-sectionally in 19 controls. The stroke patients were clinically evaluated using a stroke severity score system. The extent of the brain lesion, including injury size and degrees of white matter lesions and atrophy were evaluated by CT and magnetic resonance imaging.

RESULTS

Increased GAP-43 concentration was detected from day 7-9 to 3 weeks after stroke, compared to day 1-4 and to levels in the control group (P = 0.02 and P = 0.007). At 3-5 months after stroke GAP-43 returned to admission levels. The initial increase in GAP-43 during the nine first days was associated to stroke severity, the degree of white matter lesions and atrophy and correlated positively with infarct size (r_s = 0.65, P = 0.001).

CONCLUSIONS

The transient increase of CSF GAP-43 is important to take into account when used as a biomarker for other neurodegenerative diseases such as Alzheimer's disease. Furthermore, GAP-43 may be a marker of neuronal responses after stroke and additional studies confirming the potential of CSF GAP-43 to reflect severity and outcome of stroke in larger cohorts are warranted.

Midlife Stress in Relation to Late-Life Cerebrospinal Fluid Biomarkers of Alzheimer's Disease: A 25-Year Follow-Up Study

BACKGROUND/AIMS

Psychological stress has previously been associated with higher risk of developing late-life dementia, especially Alzheimer's disease (AD). This study tested whether longstanding midlife stress is related to cerebrospinal fluid (CSF) biomarkers of late-life AD, such as tau protein and amyloid beta (Aβ).

METHODS

The study included 79 nondemented females from the Prospective Population Study of Women in Gothenburg, Sweden, who responded to a standardized stress question at baseline (mean age 49 years) and underwent a lumbar puncture at follow-up 25 years later. Multiple linear regression models analyzed the relationships between midlife psychological stress and late-life CSF measures of total tau (t-tau), phosphorylated tau (p-tau), Aβ40, and Aβ42.

RESULTS

Longstanding stress in midlife was associated with higher levels of CSF t-tau (β = 0.64, p = 0.01) and Aβ40 (β = 0.60, p = 0.02) in late life. No associations were found between midlife stress and levels of p-tau or Aβ42.

CONCLUSION

The findings suggest that longstanding stress stimulates unspecific neurodegenerative processes, but not the core processes of AD, at least not in the early phase of the disease. The association with higher concentration of CSF t-tau may reflect neural degeneration and the association with higher Aβ40 may be an early sign of Aβ overproduction or cerebrovascular processes in the brain.

Cerebrospinal fluid protein markers in PD patients after DBS-STN surgery-A retrospective analysis of patients that underwent surgery between 1993 and 2001

OBJECTIVE

Cerebrospinal fluid (CSF) markers of neurodegeneration [neurofilament light chain (NFL), total Tau (T-Tau)], tau pathology [phosphorylated tau (p-Tau)], glial cell damage or activation [glial fibrillary acidic protein (GFAP)], and brain amyloidosis [β-amyloid 1-42 (Aβ42)] are useful for diagnosis and prognosis in several neurodegenerative disorders. In this paper we investigate these markers and their relationship to key clinical milestones in patients with advanced Parkinson´s disease (PD) operated at our center with subthalamic nucleus deep brain stimulation (STN-DBS) for at least 15 years ago.

PATIENTS AND METHODS

Retrospective analysis of available cerebrospinal fluid and clinical data in PD-patients, 15 years or more after they underwent STN-DBS surgery. All PD-patients implanted with STN-DBS at Sahlgrenska University Hospital before January 1, 2001, were regularly assessed until January 10, 2018, or until death, or until lost to follow-up.

RESULTS

Twenty three PD patients were operated with STN-DBS. Sixteen of these (six females and ten males) underwent at least one lumbar puncture (LP) immediately prior to or after STN-DBS. Their age at the latest available LP was 64 (55-75) years [median (range)], PD duration 20 (11-33) years, and Hoehn & Yahr (H&Y) stage 3 (2-4). Time between DBS operation and the last LP was 4.5 (0.3-10.8) years. Time from the last LP to the last follow up was 6 (0.1-18) years, and for the entire cohort 115 person-years. On January 10, 2018, four PD-patients (25%) were still alive. All preoperative CSF marker levels were normal. Between two days and six months after DBS, NFL and GFAP levels increased sharply but they normalized thereafter in most patients, and were normal up to almost 11 years after neurosurgery. Over time, all patients deteriorated slowly. At the last follow up, H&Y was 5 (3-5) and 12/16 were demented. There was no significant correlation between postoperative (> 6 months) CSF NFL, GFAP, T-Tau, p-Tau, β-amyloid levels and the presence of dementia, psychosis, inability to walk or need for nursing home at the time for LP, nor for presence of dementia at the last follow up or for death as of January 10, 2018.

CONCLUSION

CSF protein biomarkers remain normal despite long PD duration, severe disability, and chronic STN-DBS. They cannot be used for PD staging or prognostication but may indicate brain damage caused by other pathological factors.

Endovascular treatment of acute ischemic stroke in the posterior circulation

Background and purpose Recent randomized clinical trials have proved the efficacy of endovascular treatment of acute ischemic stroke in the anterior circulation. However, the benefit of endovascular treatment of ischemic stroke in the posterior circulation remains to be proven since it was excluded from these trials. We evaluate the benefit of endovascular treatment in posterior circulation strokes. Methods A total of 110 consecutive patients with posterior circulation stroke who underwent endovascular treatment in our institute in the period 1991-2015 were included. Recanalization rate according to modified Treatment in Cerebral Ischemia score and neurological outcome at three months according to modified Rankin Scale were the main outcomes. Collateral circulation, procedural complications and radiological outcome were evaluated in the radiological examinations. Results The median National Institutes of Health Stroke Scale was 31 (IQR: 13-31) and median time from symptom onset to groin puncture was 300 (IQR: 175-463) minutes. Successful recanalization was seen in 80 of 110 patients (73%). Favorable outcome (modified Rankin Scale ≤2) was seen in 38 patients (35%) while moderate favorable outcome (≤3) was seen in 48 patients (44%). Symptomatic intracerebral hemorrhage occurred in 10 patients (9%). An association between collateral circulation, recanalization rate and outcome was seen. Conclusion Endovascular treatment for posterior circulation stroke in this single-center cohort is relatively safe and effective with decreased mortality and increased favorable outcome compared to natural history.

Impact of the Swedish National Stroke Campaign on stroke awareness

BACKGROUND

Time delay from stroke onset to arrival in hospital is an important obstacle to widespread reperfusion therapy. To increase knowledge about stroke, and potentially decrease this delay, a 27-month national public information campaign was carried out in Sweden.

AIMS

To assess the effects of a national stroke campaign in Sweden.

METHODS

The variables used to measure campaign effects were knowledge of the AKUT test [a Swedish equivalent of the FAST (Face-Arm-Speech-Time)] test and intent to call 112 (emergency telephone number) . Telephone interviews were carried out with 1500 randomly selected people in Sweden at eight points in time: before, three times during, immediately after, and nine, 13 and 21 months after the campaign.

RESULTS

Before the campaign, 4% could recall the meaning of some or all keywords in the AKUT test, compared with 23% during and directly after the campaign, and 14% 21 months later. Corresponding figures were 15%, 51%, and 50% for those remembering the term AKUT and 65%, 76%, and 73% for intent to call 112 when observing or experiencing stroke symptoms. During the course of the campaign, improvement of stroke knowledge was similar among men and women, but the absolute level of knowledge for both items was higher for women at all time points.

CONCLUSION

The nationwide campaign substantially increased knowledge about the AKUT test and intention to call 112 when experiencing or observing stroke symptoms, but knowledge declined post-intervention. Repeated public information therefore appears essential to sustain knowledge gains.

Editor's Choice - Very Urgent Carotid Endarterectomy is Associated with an Increased Procedural Risk: The Carotid Alarm Study

OBJECTIVE/BACKGROUND

The aim of the Carotid Alarm Study was to compare the procedural risk of carotid endarterectomy (CEA) performed within 48 hours with that after 48 hours to 14 days following an ipsilateral cerebrovascular ischaemic event.

METHODS

Consecutive patients with symptomatic carotid stenosis undergoing CEA were prospectively recruited. Time to surgery was calculated as time from the most recent ischaemic event preceding surgery. A neurologist examined patients before and, after CEA. The primary endpoint was the composite endpoint of death and/or any stroke within 30 days of the surgical procedure. The study was designed to include 600 patients, with 150 operated on within 48 hours.

RESULTS

From October 2010 to December 2015, 418 patients were included, of whom 75 were operated within 48 hours of an ischaemic event. The study was prematurely terminated owing to the slow recruitment rate in the group operated on within 48 hours. Patients undergoing CEA within 48 hours had a higher risk of reaching the primary endpoint than those operated on later (8.0% vs. 2.9%). Multivariate logistic regression analyses showed that CEA performed within 48 h (odds ratio [OR] 3.07; 95% confidence interval [CI] 1.04-9.09), CEA performed out of office hours (OR 3.65; 95% CI 1.14-11.67), and use of shunt (OR 4.02; 95% CI 1.36-11.93) were all independently associated with an increased risk of reaching the primary endpoint.

CONCLUSION

CEA performed within 48 hours was associated with a higher risk of complications compared with surgery performed 48 hours-14 days after the most recent ischaemic event.

General Anesthesia Versus Conscious Sedation for Endovascular Treatment of Acute Ischemic Stroke

Background and Purpose—

Retrospective studies have found that patients receiving general anesthesia for endovascular treatment in acute ischemic stroke have worse neurological outcome compared with patients receiving conscious sedation. In this prospective randomized single-center study, we investigated the impact of anesthesia technique on neurological outcome in acute ischemic stroke patients.

Methods—

Ninety patients receiving endovascular treatment for acute ischemic stroke in 2013 to 2016 were included and randomized to general anesthesia or conscious sedation. Difference in neurological outcome at 3 months, measured as modified Rankin Scale score, was analyzed (primary outcome) and early neurological improvement of National Institutes of Health Stroke Scale and cerebral infarction volume. Age, sex, comorbidities, admission National Institutes of Health Stroke Scale score, intraprocedural blood pressure, blood glucose, Paco 2 and Pco 2 modified Thrombolysis in Cerebral Ischemia score, and relevant time intervals were recorded.

Results—

In the general anesthesia group 19 of 45 patients (42.2%) and in the conscious sedation group 18 of 45 patients (40.0%) achieved a modified Rankin Scale score ≤2 ( P =1.00) at 3 months, with no differences in intraoperative blood pressure decline from baseline ( P =0.57); blood glucose ( P =0.94); PaCO2 ( P =0.68); time intervals ( P =0.78); degree of successful recanalization, 91.1% versus 88.9% ( P =1.00); National Institutes of Health Stroke Scale score at 24 hours 8 (3–5) versus 9 (2–15; P =0.60); infarction volume, 20 (10–100) versus 20(10–54) mL ( P =0.53); and hospital mortality (13.3% in both groups; P =1.00).

Conclusions—

In endovascular treatment for acute ischemic stroke, no difference was found between general anesthesia and conscious sedation in neurological outcome 3 months after stroke.

Clinical Trial Registration—

URL: https://www.clinicaltrials.gov . Unique identifier: NCT01872884.

Cerebrospinal fluid markers of neuronal and glial cell damage in patients with autoimmune neurologic syndromes with and without underlying malignancies

Autoimmune neurologic syndromes can be paraneoplastic (associated with malignancies and/or onconeural antibodies), or non-paraneoplastic. Their clinical presentation is often similar. As prognosis is related to malignancy treatment, better biomarkers are needed to identify patients with malignancy. We investigated cerebrospinal fluid (CSF) markers of neuronal (neurofilament light chain, NFL and total tau protein, T-tau) and glial (glial fibrillary acidic protein) damage. CSF-NFL and T-tau were increased in both paraneoplastic and non-paraneoplastic autoimmune syndromes. Patients with manifest malignancies were older, had less epilepsy, more focal central and peripheral neurological signs and symptoms, and worse long-term outcome, than those without malignancy. CSF-NFL-levels predicted long-term outcome but were not diagnostic for malignancy, after age adjustment.

Cerebrospinal fluid markers of neuronal and glial cell damage to monitor disease activity and predict long-term outcome in patients with autoimmune encephalitis

BACKGROUND AND PURPOSE

Clinical symptoms and long-term outcome of autoimmune encephalitis are variable. Diagnosis requires multiple investigations, and treatment strategies must be individually tailored. Better biomarkers are needed for diagnosis, to monitor disease activity and to predict long-term outcome. The value of cerebrospinal fluid (CSF) markers of neuronal [neurofilament light chain protein (NFL), and total tau protein (T-tau)] and glial cell [glial fibrillary acidic protein (GFAP)] damage in patients with autoimmune encephalitis was investigated.

METHODS

Demographic, clinical, magnetic resonance imaging, CSF and antibody-related data of 25 patients hospitalized for autoimmune encephalitis and followed for 1 year were retrospectively collected. Correlations between these data and consecutive CSF levels of NFL, T-tau and GFAP were investigated. Disability, assessed by the modified Rankin scale, was used for evaluation of disease activity and long-term outcome.

RESULTS

The acute stage of autoimmune encephalitis was accompanied by high CSF levels of NFL and T-tau, whereas normal or significantly lower levels were observed after clinical improvement 1 year later. NFL and T-tau reacted in a similar way but at different speeds, with T-tau reacting faster. CSF levels of GFAP were initially moderately increased but did not change significantly later on. Final outcome (disability at 1 year) directly correlated with CSF-NFL and CSF-GFAP levels at all time-points and with CSF-T-tau at 3 ± 1 months. This correlation remained significant after age adjustment for CSF-NFL and T-tau but not for GFAP.

CONCLUSION

In autoimmune encephalitis, CSF levels of neuronal and glial cell damage markers appear to reflect disease activity and long-term disability.

Hypotension During Endovascular Treatment of Ischemic Stroke Is a Risk Factor for Poor Neurological Outcome

Background and Purpose—

In retrospective studies, patients receiving general anesthesia for endovascular treatment for acute ischemic stroke have worse neurological outcome compared with patients receiving conscious sedation. It has been suggested that this is caused by general anesthesia–associated hypotension. We investigated the effect of intraprocedural hypotension on neurological outcome.

Methods—

One hundred eight patients with acute ischemic stroke, who underwent endovascular treatment in general anesthesia between 2007 and 2012, were included. Analyzed predictors of neurological outcome were age, sex, comorbidities, baseline National Institutes of Health Stroke Scale, intraprocedural relative changes in mean arterial blood pressure from baseline, blood glucose, modified Thrombolysis in Cerebral Infarction score, and elapsed time from stroke to computed tomography, groin puncture, and recanalization/end of procedure.

Results—

A fall in mean arterial blood pressure of >40% was an independent predictor for poor neurological outcome ( P =0.032), as were higher admission National Institutes of Health Stroke Scale score ( P =0.008) and lack of recanalization ( P =0.003).

Conclusions—

Profound intraprocedural hypotension is an independent predictor for poor neurological outcome in patients with acute ischemic stroke undergoing endovascular therapy in general anesthesia.

Psychometric properties of the Satisfaction With Life Scale in Parkinson's disease

OBJECTIVE

The Satisfaction With Life Scale (SWLS) is a global measure of life satisfaction (LS). The objective of this study was to evaluate the psychometric properties (data completeness, scaling assumptions, targeting and reliability) of the SWLS in a sample of people with Parkinson's disease (PD).

MATERIALS AND METHODS

A postal survey including a Swedish version of the SWLS and demographic information was administered to 174 persons with PD; 97 responded and received a second survey after 2 weeks.

RESULTS

The mean (SD) age and PD duration of the 97 responders were 73 (8) and 7 (6) years, respectively. Data completeness was 92% to 97% for the five items in the SWLS and 92% for the total score (5-35 points). The mean score of the SWLS was 24.2 points (7.7), indicating that this group had an average LS. The items' means and SDs were roughly parallel and the score distribution was even. The internal consistency reliability (Cronbach's alpha) was 0.90. The test-retest reliability, assessed by the intraclass correlation coefficient, was 0.78. The scale showed no systematic difference between the first and second response. The standard error of measurement was 3.6 points, and the smallest detectable difference was 10.0 points.

CONCLUSIONS

This evaluation of the psychometric properties of the SWLS shows that the scale has good data completeness, scaling assumptions and targeting and that the internal consistency reliability and the test-retest reliability are acceptable. Thus, the SWLS is a psychometrically sound and suitable tool to asses LS in people with PD.

Public stroke awareness and intent to call 112 in Sweden

BACKGROUND AND AIMS

Recognition of stroke symptoms and activation of emergency services are essential in minimizing delay for acute stroke treatments. In this study, we assessed public stroke awareness in Sweden.

METHODS

One thousand and five hundred residents aged 18-79 years participated in a telephone survey. Open-ended questions were used to assess knowledge of stroke symptoms, risk factors, and action if witnessing or experiencing a potential stroke.

RESULTS

Seventy-two percentage could report at least one stroke symptom and 86% at least one risk factor. Only 13% could report three or more stroke symptoms. Female sex (OR, 1.79; 95% CI, 1.30-2.45) and high education (OR, 2.30; 95% CI, 1.38-3.80) were associated with knowledge of stroke symptoms. Sixty-five percentage indicated they would call the emergency number 112 if witnessing or experiencing a potential stroke. Female sex (OR, 1.48; 95% CI, 1.18-1.85) and high education (OR, 1.40; 95% CI, 1.01-1.93) were positively associated, while increasing age (OR, 0.99; 95% CI, 0.98-0.99) was negatively associated with intent to call 112.

CONCLUSION

We confirm a rather low public awareness of stroke in Sweden, poorer among males and those with low education. With increasing age, a lower proportion indicated intent to call 112 for stroke symptoms.

Higher CSF interleukin-6 and CSF interleukin-8 in current depression in older women. Results from a population-based sample

OBJECTIVE

The literature regarding cerebrospinal fluid (CSF) cytokines in geriatric depression is sparse. The aim of this study was to examine associations between CSF interleukin-6 (IL-6), interleukin-8 (IL-8) and depression in a population-based sample of older women who were followed for 17 years.

METHODS

86 dementia-free women aged 70-84 years who participated in the Prospective Population Study of Women in Gothenburg, Sweden took part in a lumbar puncture in 1992-3. CSF IL-6 and CSF IL-8 were measured. Psychiatric symptoms were rated with the Comprehensive Psychopathological Rating Scale at baseline and at three subsequent face-to-face examinations. Depression (major or minor) was diagnosed in accordance with DSM-IV/DSM-IV research criteria.

RESULTS

At baseline, women with ongoing major (n=10) or minor depression (n=9) had higher levels of CSF IL-6 (p=0.008) and CSF IL-8 (p=0.007) compared with those without depression (n=67). Higher CSF IL-8 was related to higher MADRS score (p=0.003). New cases of depression were observed in 9 women during follow-ups. No associations between CSF cytokine levels and future depression could be shown in women without depression at baseline.

CONCLUSION

Higher levels of CSF IL-6 and IL-8 were associated with current depression in this population-based sample. CSF IL-6 and CSF IL-8 may play a role in depression in late life.

Biomarker evidence of axonal injury in neuroasymptomatic HIV-1 patients

BACKGROUND

Prevalence of neurocognitive impairment in HIV-1 infected patients is reported to be high. Whether this is a result of active HIV-related neurodegeneration is unclear. We examined axonal injury in HIV-1 patients by measuring the light subunit of neurofilament protein (NFL) in CSF with a novel, sensitive method.

METHODS

With a cross-sectional design, CSF concentrations of neurofilament protein light (NFL) (marker of neuronal injury), neopterin (intrathecal immunoactivation) and CSF/Plasma albumin ratio (blood-brain barrier integrity) were analyzed on CSF from 252 HIV-infected patients, subdivided into untreated neuroasymptomatics (n = 200), HIV-associated dementia (HAD) (n = 14) and on combinations antiretroviral treatment (cART) (n = 85), and healthy controls (n = 204). 46 HIV-infected patients were included in both treated and untreated groups, but sampled at different timepoints. Furthermore, 78 neuroasymptomatic patients were analyzed before and after treatment initiation.

RESULTS

While HAD patients had the highest NFL concentrations, elevated CSF NFL was also found in 33% of untreated neuroasymptomatic patients, mainly in those with blood CD4+ cell counts below 250 cells/μL. CSF NFL concentrations in the untreated neuroasymptomatics and treated groups were equivalent to controls 18.5 and 3.9 years older, respectively. Neopterin correlated with NFL levels in untreated groups while the albumin ratio correlated with NFL in both untreated and treated groups.

CONCLUSIONS

Increased CSF NFL indicates ongoing axonal injury in many neuroasymptomatic patients. Treatment decreases NFL, but treated patients retain higher levels than controls, indicating either continued virus-related injury or an aging-like effect of HIV infection. NFL correlates with neopterin and albumin ratio, suggesting an association between axonal injury, neuroinflammation and blood-brain barrier permeability. NFL appears to be a sensitive biomarker of subclinical and clinical brain injury in HIV and warrants further assessment for broader clinical use.

Cerebrospinal fluid neurofilament light chain protein levels in subtypes of frontotemporal dementia

Background

Frontotemporal dementia (FTD) is recognised as a clinically and morphologically heterogeneous group of interrelated neurodegenerative conditions. One of the subtypes within this disease spectrum is the behavioural variant FTD (bvFTD). This is known to be a varied disorder with a mixture of tau-positive and tau-negative underlying pathologies. The other subtypes include semantic dementia (SD), which generally exhibits tau-negative pathology, and progressive non-fluent aphasia (PNFA), which is usually tau-positive. As the clinical presentation of these subtypes may overlap, a specific diagnosis can be difficult to attain and today no specific biomarker can predict the underlying pathology. Neurofilament light chain protein (NFL), a cytoskeletal constituent of intermediate filaments, is thought to reflect neuronal and axonal death when appearing in the cerebrospinal fluid (CSF). NFL has been shown to be elevated in CSF in patients with FTD compared with AD and controls. Our hypothesis was that the levels of NFL also differ between the subtypes of FTD and may indicate the underlying pathological subtype.

Methods

We retrospectively analysed data from previous CSF analyses in 34 FTD cases (23 bvFTD, seven SD, four PNFA), 20 AD cases, and 26 healthy controls. A separate group of 10 neuropathologically verified and subtyped FTD cases (seven tau-negative, three tau-positive) were also analysed.

Result

NFL levels were significantly higher in FTD compared with both AD (p<0.001) and controls (p<0.001). The NFL levels of SD and bvFTD were significantly higher (p<0.001) compared with AD. The biomarker profiles of PNFA and AD were similar. In the neuropathologically verified FTD cases, NFL was higher in the tau-negative than in the tau-positive cases (exact p=0.017).

Conclusions

The marked NFL elevation in some but not all FTD cases is likely to reflect the different underlying pathologies. The highest NFL values found in the SD group as well as in the neuropathologically verified tau-negative cases may be of subtype diagnostic value, if corroborated in larger patient cohorts. In bvFTD, a mixture of tau-positive and tau-negative underlying pathologies could possibly explain the intermediate NFL values.

Novel cerebrospinal fluid biomarkers of axonal degeneration in frontotemporal dementia

Frontotemporal dementia (FTD) is a heterogeneous disease with substantial interpersonal variance in aggressiveness. Novel biomarkers for rapidly progressive FTD could improve diagnosis and provide clues regarding its pathogenesis. In this study, surface-enhanced laser desorption/ionization time-of-flight (SELDI-TOF) mass spectrometry (MS) was used to analyze peptide profiles in cerebrospinal fluid (CSF) from 24 FTD patients. Thirteen patients had rapidly progressive FTD with distinct pathology in a brain MRI after less than 3 years of disease duration. Eleven patients had slowly progressive FTD with a normal brain MRI, but had abnormal findings in SPECT/PET after more than 5 years of disease duration. The axonal damage marker CSF neurofilament light-chain (NF-L) was measured in all subjects to evaluate the amount of axonal degeneration. A CSF NF-L level of 150 ng/l was used as a cut-off point for high NF-L expression. SELDI-TOF analysis of peptides in the range of 2000-20000 m/z revealed one peak with m/z of 6378 that was expressed at a significantly different level (p<0.01) when rapidly versus slowly progressive cases of FTD were compared. Eleven peaks were expressed at different levels when high versus low CSF NF-L were compared. Using chromatographic purification followed by tandem mass spectrometric analysis, five of these peaks were identified as follows: C-terminal fragment of neuroendocrine protein 7B2 (3512.84 Da), C-terminal fragment of osteopontin (7658.19 Da) as well as its mono- and diphosphorylated forms (7738.16 Da and 7818.13 Da, respectively) and pancreatic ribonuclease (14566.33 Da). The peak intensity of pancreatic ribonuclease was higher in patients with low NF-L expression, while the other peptides had a lower peak intensity in this group. Altered levels of these peptides have also been described in other neurodegenerative diseases. Taken together, these data suggest that differentially-expressed peptides are general markers of axonal degeneration. Further studies are needed to verify their prognostic value in FTD.

Light subunit of neurofilament triplet protein in the cerebrospinal fluid after subthalamic nucleus stimulation for Parkinson's disease

OBJECTIVES

Cerebrospinal fluid (CSF) levels of neurofilament triplet protein (NFL), a non-specific marker of neuronal damage, are normal in Parkinson's disease (PD) but increased after brain trauma and in several neurological disorders. Using longitudinal CSF-NFL measurements as an indicator of neuronal damage, this study investigated the impact of deep brain stimulation (DBS) of the subthalamic nucleus (STN) on the brain, directly following the surgical intervention and in chronically treated patients with PD.

MATERIALS AND METHODS

CSF-NFL levels were measured consecutively in eight patients with PD before and after STN-DBS treatment.

RESULTS

CSF-NFL levels were normal prior to STN-DBS and increased sharply during the first 2 weeks post-operatively, but normalized after 12 months or more.

CONCLUSION

The STN-DBS procedure leads to an acute but limited neuronal damage, as expected. However, normal CSF-NFL levels at 12 months post-operatively and beyond suggest the absence of any long-term neuronal damage caused by long-term STN-DBS stimulation.

No neurochemical evidence of brain injury after blast overpressure by repeated explosions or firing heavy weapons

BACKGROUND

Psychiatric and neurological symptoms are common among soldiers exposed to blast without suffering a direct head injury. It is not known whether such symptoms are direct consequences of blast overpressure.

OBJECTIVE

To examine if repeated detonating explosions or firing if of heavy weapons is associated with neurochemical evidence of brain damage.

MATERIALS AND METHODS

Three controlled experimental studies. In the first, army officers were exposed to repeated firing of a FH77B howitzer or a bazooka. Cerebrospinal fluid (CSF) was taken post-exposure to measure biomarkers for brain damage. In the second, officers were exposed for up to 150 blasts by firing a bazooka, and in the third to 100 charges of detonating explosives of 180 dB. Serial serum samples were taken after exposure. Results were compared with a control group consisting of 19 unexposed age-matched healthy volunteers.

RESULTS

The CSF biomarkers for neuronal/axonal damage (tau and neurofilament protein), glial cell injury (GFAP and S-100b), blood-brain barrier damage (CSF/serum albumin ratio) and hemorrhages (hemoglobin and bilirubin) and the serum GFAP and S-100b showed normal and stable levels in all exposed officers.

DISCUSSION

Repeated exposure to high-impact blast does not result in any neurochemical evidence of brain damage. These findings are of importance for soldiers regularly exposed to high-impact blast when firing artillery shells or other types of heavy weapons.

Axonal damage in relapsing multiple sclerosis is markedly reduced by natalizumab

OBJECTIVE

The impact of present disease-modifying treatments (DMTs) in multiple sclerosis (MS) on nerve injury and reactive astrogliosis is still unclear. Therefore, we studied the effect of natalizumab treatment on the release of 2 brain-specific tissue damage markers into cerebrospinal fluid (CSF) in MS patients.

METHODS

CSF samples from 92 patients with relapsing forms of MS were collected in a prospective manner prior to natalizumab treatment and after 6 or 12 months. In 86 cases, natalizumab was used as second-line DMT due to breakthrough of disease activity. The levels of neurofilament light (NFL) and glial fibrillary acidic protein (GFAP) were determined using highly sensitive in-house developed enzyme-linked immunosorbent assays.

RESULTS

Natalizumab treatment led to a 3-fold reduction of NFL levels, from a mean value of 1,300 (standard deviation [SD], 2,200) to 400 (SD, 270) ng/l (p < 0.001). The later value was not significantly different from that found in healthy control subjects (350 ng/l; SD, 170; n = 28). Subgroup analysis revealed a consistent effect on NFL release, regardless of previous DMT or whether patients had relapses or were in remission within 3 months prior to natalizumab treatment. No differences between pre- and post-treatment levels of GFAP were detected.

INTERPRETATION

Our data demonstrate that natalizumab treatment reduces the accumulation of nerve injury in relapsing forms of MS. It is anticipated that highly effective anti-inflammatory treatment can reduce axonal loss, thereby preventing development of permanent neurological disability.

Effects of cerebrovascular disease on amyloid precursor protein metabolites in cerebrospinal fluid

Background

Alzheimer's disease (AD) and cerebrovascular disease (CVD) including chronic small vessel disease of the brain (SVD) are the most frequent causes of dementia. AD is associated with metabolism of amyloid precursor protein (APP) and low levels of amyloid-β peptide (Aβ) X-42 in the cerebrospinal fluid (CSF). CVD and SVD are established risk factors for AD, brain white matter lesions (WML) are established surrogate markers for SVD and are also associated with reduced CSF AβX-42.

A cohort survey was performed to examine whether SVD or acute CVD affects APP metabolism and to explore a potential association between WML and APP metabolism in two groups; cognitively impaired patients, subjective and mild (SCI and MCI) and stroke patients. Through measurements of CSF APP metabolite levels in patients with a wide range of WML volumes, this study aimed to determine how SVD influences APP metabolism.

Methods

Sixty-three patients were included: 37 with subjective cognitive impairment (SCI) or mild cognitive impairment (MCI) without stroke, and 26 after acute stroke. Chronic and acute WML volume and infarct volume were determined by magnetic resonance imaging (MRI) post-scan processing, and CSF levels of α- and β-cleaved soluble APP (sAPP-α and sAPP-β, AβX-38, AβX-40 and AβX-42) were determined. The Mann-Whitney test was used to compare the patient groups. Chronic and acute WML volumes, infarct volume, age, and sex were used as predictors for CSF biomarker levels in linear regression analysis.

Results

CSF levels of sAPP-α and sAPP-β were strongly correlated (r = 0.95, p < 0.001) and lower levels of these biomarkers were found in the stroke group than in the SCI/MCI group; median sAPP-α 499.5 vs. 698.0 ng/mL (p < 0.001), sAPP-β 258.0 vs. 329.0 ng/mL (p < 0.005). CSF levels of sAPP-α, sAPP-β, AβX-38, AβX-40 and AβX-42 were inversely correlated with chronic WML volume (p ≤ 0.005; p ≤ 0.01; p ≤ 0.01; p ≤ 0.05; p ≤ 0.05 respectively), but not with acute WML or infarct volumes.

Conclusions

Lower CSF levels of sAPP-α and sAPP-β in the stroke group than in the SCI/MCI group and an inverse correlation with chronic WML indicate that ischemia lowers the levels of CSF sAPP metabolites and suggests that APP axonal transport or metabolism may be affected in SVD of the brain.

Is there a CSF biomarker profile related to depression in elderly women?

In light of our previous observation of higher levels of cerebrospinal fluid (CSF) amyloid beta-42 (Abeta42) and CSF/serum albumin ratio in major depressive disorder (MDD), we analyzed two additional CSF biomarkers reflecting neurodegeneration-neurofilament protein light (NFL) and glial fibrillary acidic protein (GFAp)-in relationship to prevalent geriatric depression. Neuropsychiatric, physical, and lumbar puncture examinations, with DSM-III-R-based depression diagnoses and measurement of CSF levels of NFL and GFAp, were evaluated among a population-based sample of 78 elderly women (mean age, 73.9+/-3.2 years) without dementia for at least 10 years after CSF collection. Eleven (13.1%) women had MDD, and higher levels of NFL compared with women without depression. A multivariate model including age, NFL, Abeta42 and the CSF/serum albumin ratio showed that each biomarker was independently and positively associated with MDD, and that this biomarker profile explained more variation in the model compared with single or combined biomarkers. A CSF profile with higher levels of NFL, Abeta42, and CSF/serum albumin ratio may indicate neuropathological and vascular events in depression etiology. This contrasts with the well-characterized pattern of low Abeta42, higher CSF/serum albumin ratio, and higher NFL in Alzheimer's disease.

Amyloid and tau cerebrospinal fluid biomarkers in HIV infection

Background

Because of the emerging intersections of HIV infection and Alzheimer's disease, we examined cerebrospinal fluid (CSF) biomarkers related of amyloid and tau metabolism in HIV-infected patients.

Methods

In this cross-sectional study we measured soluble amyloid precursor proteins alpha and beta (sAPPα and sAPPβ), amyloid beta fragment 1-42 (Aβ_1-42), and total and hyperphosphorylated tau (t-tau and p-tau) in CSF of 86 HIV-infected (HIV+) subjects, including 21 with AIDS dementia complex (ADC), 25 with central nervous system (CNS) opportunistic infections and 40 without neurological symptoms and signs. We also measured these CSF biomarkers in 64 uninfected (HIV-) subjects, including 21 with Alzheimer's disease, and both younger and older controls without neurological disease.

Results

CSF sAPPα and sAPPβ concentrations were highly correlated and reduced in patients with ADC and opportunistic infections compared to the other groups. The opportunistic infection group but not the ADC patients had lower CSF Aβ_1-42 in comparison to the other HIV+ subjects. CSF t-tau levels were high in some ADC patients, but did not differ significantly from the HIV+ neuroasymptomatic group, while CSF p-tau was not increased in any of the HIV+ groups. Together, CSF amyloid and tau markers segregated the ADC patients from both HIV+ and HIV- neuroasymptomatics and from Alzheimer's disease patients, but not from those with opportunistic infections.

Conclusions

Parallel reductions of CSF sAPPα and sAPPβ in ADC and CNS opportunistic infections suggest an effect of CNS immune activation or inflammation on neuronal amyloid synthesis or processing. Elevation of CSF t-tau in some ADC and CNS infection patients without concomitant increase in p-tau indicates neural injury without preferential accumulation of hyperphosphorylated tau as found in Alzheimer's disease. These biomarker changes define pathogenetic pathways to brain injury in ADC that differ from those of Alzheimer's disease.

Biomarkers in the cerebrospinal fluid and neurodegeneration in Langerhans cell histiocytosis

BACKGROUND

Progressive neurodegeneration may result in potentially severe cognitive and motor dysfunctions as a complication of Langerhans cell histiocytosis (LCH), a suggested IL-17A-associated inflammatory condition. To detect this complication (CNS-LCH) early and to evaluate the potential efficacy of therapeutic interventions, biomarkers detecting and measuring ongoing neurodegeneration would be valuable. We evaluated cerebrospinal fluid (CSF) biomarkers of ongoing neurodegeneration in CNS-LCH patients.

PROCEDURE

Nine patients with endocrine, neuromotor, cognitive or/and behavioral abnormalities as well as neuroradiological evidence of CNS-LCH were evaluated 4-12 years after LCH diagnosis for CSF levels of neurofilament protein light chain (NF-L), glial fibrillary acid protein (GFAp), and total tau protein (TAU). Two patients were analyzed longitudinally. One hundred ten children with newly diagnosed acute lymphoblastic leukemia (ALL) served as controls.

RESULTS

NF-L, TAU, and GFAp levels were elevated in four, six, and eight of nine patients studied, respectively. NF-L (P < 0.001) and GFAp (P < 0.001) were higher in patients than in controls (TAU not analyzed in controls). The patient with most severe clinical and neuroradiological CNS-LCH displayed the highest levels of NF-L and GFAp whereas three patients without signs of systemic disease had low TAU levels and normal/slightly elevated NF-L. NF-L tended to be higher at radiological progression of neurodegeneration than at status quo (P = 0.07). Notably, we experienced frequent lumbar puncture complications in these patients.

CONCLUSIONS

CSF levels of NF-L, TAU, and GFAp appear to be elevated in CNS-LCH. It would be valuable if these markers were validated in order to serve as markers for early CNS-LCH, to monitor disease progression and to evaluate various treatment attempts for CNS-LCH.

Differences in lesion severity and cellular composition between in vivo assessed upstream and downstream sides of human symptomatic carotid atherosclerotic plaques

BACKGROUND

The heterogeneous structure of carotid atherosclerotic plaques may be better understood if it is related to blood flow variations, influencing gene expression and cellular functions. Upstream of the maximum stenosis there is laminar blood flow and high shear stress, downstream there is turbulence and low shear stress. We studied if these variations were associated with differences in plaque morphology and composition between sites located up- and downstream of the maximum stenosis in symptomatic carotid plaques.

METHODS

Patients with symptomatic carotid stenosis were examined with magnetic resonance angiography to localize the maximum stenosis in-vivo, prior to endarterectomy. In 41 endarterectomized specimens, transverse tissue sections prepared up- and downstream of the maximum stenosis were compared using histopathology and immunohistochemistry.

RESULTS

The location of maximum stenosis relative the carotid bifurcation varied considerably between plaques. Compared with the downstream side, the upstream side of the stenosis had higher incidence of severe lesions with cap rupture and intraplaque hemorrhage, more macrophages, less smooth muscle cells and more collagen.

CONCLUSIONS

The up- and downstream sides of symptomatic carotid plaques differed in plaque morphology and composition. This implies that the intraplaque location of sampling sites may be a confounding factor in studies of atherosclerotic plaques.

Neurofilament ELISA validation

BACKGROUND

Neurofilament proteins (Nf) are highly specific biomarkers for neuronal death and axonal degeneration. As these markers become more widely used, an inter-laboratory validation study is required to identify assay criteria for high quality performance.

METHODS

The UmanDiagnostics NF-light (R)enzyme-linked immunoabsorbent assays (ELISA) for the neurofilament light chain (NfL, 68kDa) was used to test the intra-assay and inter-laboratory coefficient of variation (CV) between 35 laboratories worldwide on 15 cerebrospinal fluid (CSF) samples. Critical factors, such as sample transport and storage, analytical delays, reaction temperature and time, the laboratories' accuracy and preparation of standards were documented and used for the statistical analyses.

RESULTS

The intra-laboratory CV averaged 3.3% and the inter-laboratory CV 59%. The results from the test laboratories correlated with those from the reference laboratory (R=0.60, p<0.0001). Correcting for critical factors improved the strength of the correlation. Differences in the accuracy of standard preparation were identified as the most critical factor. Correcting for the error introduced by variation in the protein standards improved the correlation to R=0.98, p<0.0001 with an averaged inter-laboratory CV of 14%. The corrected overall inter-rater agreement was subtantial (0.6) according to Fleiss' multi-rater kappa and Gwet's AC1 statistics.

CONCLUSION

This multi-center validation study identified the lack of preparation of accurate and consistent protein standards as the main reason for a poor inter-laboratory CV. This issue is also relevant to other protein biomarkers based on this type of assay and will need to be solved in order to achieve an acceptable level of analytical accuracy. The raw data of this study is available online.

Elevated cerebrospinal fluid levels of prostaglandin E2 and 15-(S)-hydroxyeicosatetraenoic acid in multiple sclerosis

OBJECTIVE

To test the hypothesis that the arachodinic acid metabolites prostaglandin E2 (PGE2) and 15-(S)-hydroxyeicosatetraenoic acid (15(S)-HETE) in cerebrospinal fluid (CSF) are elevated and reflect neuroinflammation and degenerative changes in multiple sclerosis (MS).

PATIENTS AND METHODS

We measured PGE2 and 15(S)-HETE concentrations, as well as markers of axonal and astroglial injury in CSF from 46 MS patients, 46 healthy siblings and 50 controls.

RESULTS

We found elevated levels of both PGE2 and 15(S)-HETE in MS compared with the control and sibling groups. Siblings had lower PGE2 levels and higher 15(S)-HETE levels than controls. There were no correlations between either PGE2 or 15(S)-HETE and clinical scores of MS severity or biochemical markers of axonal or astroglial injury.

CONCLUSION

These data suggest no direct involvement of PGE2 and 15(S)-HETE in the MS disease process. Rather, the elevated levels reflect a general up-regulation of arachidonic acid metabolism and neuroinflammation.

Apolipoprotein E polymorphism and gender difference in outcome after severe traumatic brain injury

BACKGROUND

Traumatic brain injury (TBI) is one of the most common causes of death and dismal outcome among children and young adults. The morbidity and mortality differ but more aggressive monitoring and more designated neuro intensive care units have improved the results. Studies have demonstrated a connection between apolipoprotein E (APOE) genotype and outcome after TBI, but few are prospective and none is from northern Europe. APOE has three alleles: epsilon2, epsilon3 and epsilon4.

METHODS

A total of 96 patients with Glasgow coma score (GCS) < or =8 were prospectively and consecutively included. APOE genotypes were all analyzed at the same laboratory from blood samples by polymerase chain reaction-restriction fragment length polymorphism.

RESULTS

All patients were assessed at 1 year with Glasgow outcome scale extended (GOSE), National Institute of Health Stroke Scale (NIHSS) and the Barthel daily living index. The genotype was available in all patients. Twenty-six patients expressed APOE epsilon4 while 70 patients did not. Outcome demonstrated that patients with APOE epsilon4 had worse outcome vs. those lacking this allele. When subdividing patients into gender, males with APOE epsilon4 did worse, a difference not detected among female patients.

CONCLUSIONS

APOE epsilon4 correlated to worse outcome in TBI patients. We also found that males with APOE epsilon4 had poor outcome while females did not. Thus, the results indicate that genetic polymorphism may influence outcome after TBI.

Association of APOE with age at onset of sporadic amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative syndrome with familial and sporadic forms. We conducted a study including 60 sporadic and 19 familial ALS patients, 206 reference patients with other neurological disorders and 1265 neurologically healthy controls to assess the Alzheimer-associated apolipoprotein E (APOE) epsilon4 gene variant as a possible risk factor for ALS. While no major influence of APOE epsilon4 on disease risk was detected, a gene dose-dependent effect with lower age at onset of sporadic ALS in epsilon4 carriers was found (p=0.027). These data support APOE epsilon4 as a subordinate contributing factor in ALS.