Diagnostic yield of emergency MRI in non-traumatic headache

Purpose Non-traumatic headache is one of the most common neurological complaints in emergency departments. A relatively low diagnostic yield of magnetic resonance imaging (MRI) among outpatients has been previously reported, but studies of emergency patients are lacking. We sought to determine the diagnostic yield of emergency MRI among outpatients presenting to the emergency department with non-traumatic headache. Methods In this retrospective cohort study, we analyzed emergency MRI referrals in a tertiary hospital for non-traumatic headache over a five-year period. We recorded patient characteristics, relevant clinical information from the referrals, and imaging outcomes. Results In total, 696 emergency patients with non-traumatic headache underwent MRI, most within 24 h of presentation. Significant findings related to headache were found in 136 (20%) patients, and incidental findings in 22% of patients. In a multivariate model, the predisposing factors of the significant findings were age, smoking, nausea, and signs/symptoms of infection. The protective factors were numbness and history of migraine. A predictive clinical score reached only moderate performance. Conclusion Although emergency MRI shows headache-related findings in one in five patients, accurate prediction modeling remains a challenge, even with statistically significant predictors and a large sample size.</p

Diagnostic yield of emergency MRI in non-traumatic headache

Purpose: Non-traumatic headache is one of the most common neurological complaints in emergency departments. A relatively low diagnostic yield of magnetic resonance imaging (MRI) among outpatients has been previously reported, but studies of emergency patients are lacking. We sought to determine the diagnostic yield of emergency MRI among outpatients presenting to the emergency department with non-traumatic headache. Methods: In this retrospective cohort study, we analyzed emergency MRI referrals in a tertiary hospital for non-traumatic headache over a five-year period. We recorded patient characteristics, relevant clinical information from the referrals, and imaging outcomes. Results: In total, 696 emergency patients with non-traumatic headache underwent MRI, most within 24 h of presentation. Significant findings related to headache were found in 136 (20%) patients, and incidental findings in 22% of patients. In a multivariate model, the predisposing factors of the significant findings were age, smoking, nausea, and signs/symptoms of infection. The protective factors were numbness and history of migraine. A predictive clinical score reached only moderate performance. Conclusion: Although emergency MRI shows headache-related findings in one in five patients, accurate prediction modeling remains a challenge, even with statistically significant predictors and a large sample size.publishedVersionPeer reviewe

Genetic risk factors in Finnish patients with Parkinson's disease

Introduction Variation contributing to the risk of Parkinson's disease (PD) has been identified in several genes and at several loci including GBA, SMPD1, LRRK2, POLG1, CHCHD10 and MAPT, but the frequencies of risk variants seem to vary according to ethnic background. Our aim was to analyze how variation in these genes contributes to PD in the Finnish population. Methods The subjects consisted of 527 Finnish patients with early-onset PD, 325 patients with late-onset PD and 403 population controls. We screened for known genetic risk variants in GBA, SMPD1, LRRK2, POLG1, CHCHD10 and MAPT. In addition, DNA from 225 patients with early-onset Parkinson's disease was subjected to whole exome sequencing (WES). Results We detected a significant difference in the length variation of the CAG repeat in POLG1 between patients with early-onset PD compared to controls. The p.N370S and p.L444P variants in GBA contributed to a relative risk of 3.8 in early-onset PD and 2.5 in late-onset PD. WES revealed five variants in LRRK2 and SMPD1 that were found in the patients but not in the Finnish ExAC sequences. These are possible risk variants that require further confirmation. The p.G2019S variant in LRRK2, common in North African Arabs and Ashkenazi Jews, was not detected in any of the 849 PD patients. Conclusions The POLG1 CAG repeat length variation and the GBA p.L444P variant are associated with PD in the Finnish population.Peer reviewe

Finnish Parkinson's disease study integrating protein-protein interaction network data with exome sequencing analysis

Variants associated with Parkinson's disease (PD) have generally a small effect size and, therefore, large sample sizes or targeted analyses are required to detect significant associations in a whole exome sequencing (WES) study. Here, we used protein-protein interaction (PPI) information on 36 genes with established or suggested associations with PD to target the analysis of the WES data. We performed an association analysis on WES data from 439 Finnish PD subjects and 855 controls, and included a Finnish population cohort as the replication dataset with 60 PD subjects and 8214 controls. Single variant association (SVA) test in the discovery dataset yielded 11 candidate variants in seven genes, but the associations were not significant in the replication cohort after correction for multiple testing. Polygenic risk score using variants rs2230288 and rs2291312, however, was associated to PD with odds ratio of 2.7 (95% confidence interval 1.4-5.2; p < 2.56e-03). Furthermore, an analysis of the PPI network revealed enriched clusters of biological processes among established and candidate genes, and these functional networks were visualized in the study. We identified novel candidate variants for PD using a gene prioritization based on PPI information, and described why these variants may be involved in the pathogenesis of PD

Association of biallelic RFC1 expansion with early-onset Parkinson's disease

Background and Purpose: The biallelic repeat expansion (AAGGG)exp in the replication factor C subunit 1 gene (RFC1) is a frequent cause of cerebellar ataxia, neuropathy and vestibular areflexia syndrome (CANVAS) as well as late-onset ataxia. The clinical spectrum of RFC1 disease has expanded since the first identification of biallelic (AAGGG)exp and includes now various nonclassical phenotypes. Biallelic (AAGGG)exp in RFC1 in patients with clinically confirmed Parkinson's disease (PD) has recently been found. Methods: A nationwide cohort of 273 Finnish patients with early-onset PD was examined for the biallelic intronic expansion in RFC1. The expansion (AAGGG)exp was first screened using extra long polymerase chain reactions (Extra Large-PCRs) and flanking multiplex PCR. The presence of biallelic (AAGGG)exp was then confirmed by repeat-primed PCR and, finally, the repeat length was determined by long-read sequencing. Results: Three patients were found with the biallelic (AAGGG)exp in RFC1 giving a frequency of 1.10% (0.23%–3.18%; 95% confidence interval). The three patients fulfilled the diagnostic criteria of PD, none of them had ataxia or neuropathy, and only one patient had a mild vestibular dysfunction. The age at onset of PD symptoms was 40–48 years and their disease course had been unremarkable apart from the early onset. Conclusions: Our results suggest that (AAGGG)exp in RFC1 is a rare cause of early-onset PD. Other populations should be examined in order to determine whether our findings are specific to the Finnish population.publishedVersionPeer reviewe

Searching for Explanations for Cryptogenic Stroke in the Young: Revealing the Triggers, Causes, and Outcome (SECRETO): Rationale and design

Background: Worldwide, about 1.3 million annual ischaemic strokes (IS) occur in adults aged <50 years. Of these early-onset strokes, up to 50% can be regarded as cryptogenic or associated with conditions with poorly documented causality like patent foramen ovale and coagulopathies. Key hypotheses/aims: (1) Investigate transient triggers and clinical/sub-clinical chronic risk factors associated with cryptogenic IS in the young; (2) use cardiac imaging methods exceeding state-of-the-art to reveal novel sources for embolism; (3) search for covert thrombosis and haemostasis abnormalities; (4) discover new disease pathways using next-generation sequencing and RNA gene expression studies; (5) determine patient prognosis by use of phenotypic and genetic data; and (6) adapt systems medicine approach to investigate complex risk-factor interactions. Design: Searching for Explanations for Cryptogenic Stroke in the Young: Revealing the Etiology, Triggers, and Outcome (SECRETO; NCT01934725) is a prospective multi-centre case–control study enrolling patients aged 18–49 years hospitalised due to first-ever imaging-proven IS of undetermined etiology. Patients are examined according to a standardised protocol and followed up for 10 years. Patients are 1:1 age- and sex-matched to stroke-free controls. Key study elements include centralised reading of echocardiography, electrocardiography, and neurovascular imaging, as well as blood samples for genetic, gene-expression, thrombosis and haemostasis and biomarker analysis. We aim to have 600 patient– control pairs enrolled by the end of 2018. Summary: SECRETO is aiming to establish novel mechanisms and prognosis of cryptogenic IS in the young and will provide new directions for therapy development for these patients. First results are anticipated in 2019

Obesity and the Risk of Cryptogenic Ischemic Stroke in Young Adults

Objectives: We examined the association between obesity and early-onset cryptogenic ischemic stroke (CIS) and whether fat distribution or sex altered this association. Materials and Methods: This prospective, multi-center, case-control study included 345 patients, aged 18-49 years, with first-ever, acute CIS. The control group included 345 age-and sex-matched stroke-free individuals. We measured height, weight, waist circumference, and hip circumference. Obesity metrics analyzed included body mass index (BMI), waist-to-hip ratio (WHR), waist-to-stature ratio (WSR), and a body shape index (ABSI). Models were adjusted for age, level of education, vascular risk factors, and migraine with aura. Results: After adjusting for demographics, vascular risk factors, and migraine with aura, the highest tertile of WHR was associated with CIS (OR for highest versus lowest WHR tertile 2.81, 95%CI 1.43-5.51; P=0.003). In sex-specific analyses, WHR tertiles were not associated with CIS. However, using WHO WHR cutoff values (>0.85 for women, >0.90 for men), abdominally obese women were at increased risk of CIS (OR 2.09, 95%CI 1.02-4.27; P=0.045). After adjusting for confounders, WC, BMI, WSR, or ABSI were not associated with CIS. Conclusions: Abdominal obesity measured with WHR was an independent risk factor for CIS in young adults after rigorous adjustment for concomitant risk factors.Peer reviewe

Obesity and the Risk of Cryptogenic Ischemic Stroke in Young Adults

ObjectivesWe examined the association between obesity and early-onset cryptogenic ischemic stroke (CIS) and whether fat distribution or sex altered this association.Materials and MethodsThis prospective, multi-center, case-control study included 345 patients, aged 18-49 years, with first-ever, acute CIS. The control group included 345 age- and sex-matched stroke-free individuals. We measured height, weight, waist circumference, and hip circumference. Obesity metrics analyzed included body mass index (BMI), waist-to-hip ratio (WHR), waist-to-stature ratio (WSR), and a body shape index (ABSI). Models were adjusted for age, level of education, vascular risk factors, and migraine with aura.ResultsAfter adjusting for demographics, vascular risk factors, and migraine with aura, the highest tertile of WHR was associated with CIS (OR for highest versus lowest WHR tertile 2.81, 95%CI 1.43-5.51; P=0.003). In sex-specific analyses, WHR tertiles were not associated with CIS. However, using WHO WHR cutoff values (>0.85 for women, >0.90 for men), abdominally obese women were at increased risk of CIS (OR 2.09, 95%CI 1.02-4.27; P=0.045). After adjusting for confounders, WC, BMI, WSR, or ABSI were not associated with CIS.ConclusionsAbdominal obesity measured with WHR was an independent risk factor for CIS in young adults after rigorous adjustment for concomitant risk factors.</p

Identification of novel risk loci, causal insights, and heritable risk for Parkinson's disease: a meta-analysis of genome-wide association studies

Background Genome-wide association studies (GWAS) in Parkinson's disease have increased the scope of biological knowledge about the disease over the past decade. We aimed to use the largest aggregate of GWAS data to identify novel risk loci and gain further insight into the causes of Parkinson's disease. Methods We did a meta-analysis of 17 datasets from Parkinson's disease GWAS available from European ancestry samples to nominate novel loci for disease risk. These datasets incorporated all available data. We then used these data to estimate heritable risk and develop predictive models of this heritability. We also used large gene expression and methylation resources to examine possible functional consequences as well as tissue, cell type, and biological pathway enrichments for the identified risk factors. Additionally, we examined shared genetic risk between Parkinson's disease and other phenotypes of interest via genetic correlations followed by Mendelian randomisation. Findings Between Oct 1, 2017, and Aug 9, 2018, we analysed 7·8 million single nucleotide polymorphisms in 37 688 cases, 18 618 UK Biobank proxy-cases (ie, individuals who do not have Parkinson's disease but have a first degree relative that does), and 1·4 million controls. We identified 90 independent genome-wide significant risk signals across 78 genomic regions, including 38 novel independent risk signals in 37 loci. These 90 variants explained 16–36% of the heritable risk of Parkinson's disease depending on prevalence. Integrating methylation and expression data within a Mendelian randomisation framework identified putatively associated genes at 70 risk signals underlying GWAS loci for follow-up functional studies. Tissue-specific expression enrichment analyses suggested Parkinson's disease loci were heavily brain-enriched, with specific neuronal cell types being implicated from single cell data. We found significant genetic correlations with brain volumes (false discovery rate-adjusted p=0·0035 for intracranial volume, p=0·024 for putamen volume), smoking status (p=0·024), and educational attainment (p=0·038). Mendelian randomisation between cognitive performance and Parkinson's disease risk showed a robust association (p=8·00 × 10−7). Interpretation These data provide the most comprehensive survey of genetic risk within Parkinson's disease to date, to the best of our knowledge, by revealing many additional Parkinson's disease risk loci, providing a biological context for these risk factors, and showing that a considerable genetic component of this disease remains unidentified. These associations derived from European ancestry datasets will need to be followed-up with more diverse data. Funding The National Institute on Aging at the National Institutes of Health (USA), The Michael J Fox Foundation, and The Parkinson's Foundation (see appendix for full list of funding sources)

Leaving a legacy of stroke in Europe: A community of dedicated professionals is changing the face of stroke in Europe

Time is of the essence in the treatment of acute stroke; however, there are wide variations, across and within countries, in the ability to hospitalize, scan, diagnose, and treat acute stroke patients rapidly within the accepted time window of 4.5 hours. Door-to-needle (DTN) time is an important performance indicator that illustrates the speed and operational efficiency of stoke units. Significant progress is being made; DTNs often exceeded an hour only a few years ago, but can now be achieved in under seven minutes in leading stroke units. This symposium examined the strategies and contributory factors that result in reduced DTN times, and how these strategies can be more widely implemented. The Quality in Acute Stroke Care (QASC) programme in Australia has shown the incorporation of standardized nurse-led treatment protocols for the management of fever, hyperglycaemia, and dysphagia (FeSS protocols) significantly improve outcomes for stroke patients. European evaluation of these protocols, in collaboration with ESO and the ANGELS initiative, and potentially leading to their adoption in European acute stroke treatment practice is discussed