A parsimonious score with a free web tool for predicting disability after an ischemic stroke: the Parsifal Score.

BACKGROUND: Most of the models to predict prognosis after an ischemic stroke include complex mathematical equations or too many variables, making them difficult to use in the daily clinic. We want to predict disability 3 months after an ischemic stroke in an independent patient not receiving recanalization treatment within the first 24 h, using a minimum set of variables and an easy tool to facilitate its implementation. As a secondary aim, we calculated the capacity of the score to predict an excellent/devastating outcome and mortality. METHODS: Eight hundred and forty-four patients were evaluated. A multivariable ordinal logistic regression was used to obtain the score. The Modified Rankin Scale (mRS) was used to estimate disability at the third month. The results were replicated in another independent cohort (378 patients). The "polr" function of R was used to perform the regression, stratifying the sample into seven groups with different cutoffs (from mRS 0 to 6). RESULTS: The Parsifal score was generated with: age, previous mRS, initial NIHSS, glycemia on admission, and dyslipidemia. This score predicts disability with an accuracy of 80-76% (discovery-replication cohorts). It has an AUC of 0.86 in the discovery and replication cohort. The specificity was 90-80% (discovery-replication cohorts); while, the sensitivity was 64-74% (discovery-replication cohorts). The prediction of an excellent or devastating outcome, as well as mortality, obtained good discrimination with AUC > 0.80. CONCLUSIONS: The Parsifal Score is a model that predicts disability at the third month, with only five variables, with good discrimination and calibration, and being replicated in an independent cohort.

The UCP2-866G/A Polymorphism Could be Considered as a Genetic Marker of Different Functional Prognosis in Ischemic Stroke After Recanalization.

Recent studies based on experimental animal models of stroke have suggested that uncoupling protein 2 (UCP2), an inner mitochondrial membrane protein that is thought to regulate energy metabolism and reduce reactive oxygen species generation, provides protection against reperfusion damage. We aimed to investigate whether -866G/A polymorphism in the promoter of the UCP2 gene, which enhances its transcriptional activity, is associated with functional prognosis in patients with embolic ischemic stroke after early recanalization. We investigate a hospital-based prospective cohort of patients with acute ischemic stroke due to occlusion of the middle cerebral artery diagnosed by transcranial Doppler who obtained a partial/complete recanalization 24 h after administration of intravenous thrombolysis. The main end point of the study was functional independence defined as modified Rankin Scale 0-2 on day 90. A total of 80 patients were enrolled. The UCP2-866G/A polymorphism was determined by polymerase chain reaction-restriction fragment length polymorphism technique (14 genotype A/A (18%), 45 genotype A/G (56%) and 21 genotype G/G (26%). The percentage of patients with good functional outcome at 3 months was significantly higher in patients harboring the A/A genotype than in those with A/G or G/G genotypes (85 vs 41%, p = 0.01). The A/A genotype was found to be an independent marker of good prognosis after adjustment for secondary variables (age, sex, glucose level, NIHSS score at baseline, complete recanalization and early neurological improvement) in a logistic regression analysis (OR 0.05, 95% CI 0.01-0.48, p = 0.01). Our results suggest that the AA genotype of UCP2-866 may predict a better functional outcome in ischemic stroke after recanalization of proximal MCA occlusion.

La resistencia en el tratamiento secundario del ictus isquémico, el componente genético en la respuesta a ácido acetilsalicílico y clopidogrel / Drug resistance and secondary treatment of ischaemic stroke: The genetic component of the response to acetylsalicylic acid and clopidogrel

Introducción: Las enfermedades cerebrovasculares están entre las principales causas de mortalidad y discapacidad en los países desarrollados. El ácido acetilsalicílico (AAS) y el clopidogrel son los tratamientos antiagregantes plaquetarios más utilizados para la profilaxis de nuevos eventos tromboembólicos. Sin embargo, se han observado casos en los que el tratamiento antiagregante no inhibe la actividad plaquetaria, un fenómeno llamado resistencia y que posiblemente puede estar modulado a nivel genético. Desarrollo: Tras una búsqueda bibliográfica se realizó una revisión sobre el estado actual del tratamiento antiagregante plaquetario. Se tratan los diferentes tipos de resistencia a la terapia antiagregante, de qué manera se mide, la problemática y limitaciones actuales, así como los factores genéticos que se han asociado a esta resistencia. Principalmente se analizan los estudios genéticos realizados en el campo de la resistencia a AAS y clopidogrel mediante Genome Wide Association. Conclusiones: Parece existir una asociación entre diferentes factores genéticos y la resistencia a los fármacos antiagregantes medida mediante la actividad plaquetaria; no obstante, no hay una asociación evidente entre estos factores genéticos y el riesgo de nuevos eventos tromboembólicos

Introduction: Cerebrovascular diseases are among the leading causes of death and disability in developed countries. Acetylsalicylic acid (ASA) and clopidogrel are the most widely-used antiplatelet drugs for secondary prevention of recurrent thromboembolic events. However, there have been cases in which antiplatelet drugs did not inhibit platelet activity; this phenomenon is called resistance, and it may be modulated at the genetic level. Development: Following a literature search, we reviewed the current state of antiplatelet therapy and covered the different types of resistance to antiplatelet therapy, how it is measured, current problems and limitations, and any genetic factors that have been associated with resistance. We mainly used the Genome Wide Association Studies in the field of ASA and clopidogrel resistance. Conclusions: We observed an association between different genetic factors and antiplatelet drug resistance as measured by platelet activity. However, there is no evident association between these genetic factors and risk of new thromboembolic events

Candidate-gene association study searching for genetic factors involved in migraine chronification.

INTRODUCTION: Chronic migraine (CM) is at the severe end of the clinical migraine spectrum, but its genetic background is unknown. Our study searched for evidence that genetic factors are involved in the chronification process. METHODS: We initially selected 144 single-nucleotide polymorphisms (SNPs) from 48 candidate genes, which we tested for association in two stages: The first stage encompassed 262 CM patients, the second investigated 226 patients with high-frequency migraine (HFM). Subsequently, SNPs with p values < 0.05 were forwarded to the replication stage containing 531 patients with CM or HFM. RESULTS: Eight SNPs were significantly associated with CM and HFM in the two-stage phase. None survived replication in the third stage. DISCUSSION: We present the first comprehensive genetic association study for migraine chronification. There were no significant findings. Future studies may benefit from larger, genome-wide data sets or should use other genetic approaches to identify genetic factors involved in migraine chronification.

Drug resistance and secondary treatment of ischaemic stroke: The genetic component of the response to acetylsalicylic acid and clopidogrel.

INTRODUCTION: Cerebrovascular diseases are among the leading causes of death and disability in developed countries. Acetylsalicylic acid (ASA) and clopidogrel are the most widely-used antiplatelet drugs for secondary prevention of recurrent thromboembolic events. However, there have been cases in which antiplatelet drugs did not inhibit platelet activity; this phenomenon is called resistance, and it may be modulated at the genetic level. DEVELOPMENT: Following a literature search, we reviewed the current state of antiplatelet therapy and covered the different types of resistance to antiplatelet therapy, how it is measured, current problems and limitations, and any genetic factors that have been associated with resistance. We mainly used the Genome Wide Association Studies in the field of ASA and clopidogrel resistance. CONCLUSIONS: We observed an association between different genetic factors and antiplatelet drug resistance as measured by platelet activity. However, there is no evident association between these genetic factors and risk of new thromboembolic events.

Aproximación al conocimiento de las bases genéticas del ictus. Consorcio español de genética del ictus / Exploring the genetic basis of stroke. Spanish stroke genetics consortium

El presente artículo revisa la evolución de los estudios en genética del ictus desde la aproximación por gen candidato hasta los recientes estudios de genome wide association. Se destaca la complejidad de esta afección por sus muy variados mecanismos etiopatogénicos, las dificultades que comporta el estudio de su componente genético y las soluciones que se han aportado. Se subraya en especial el valor de las colaboraciones entre distintos centros, ya sea de manera puntual o sobre todo a través de la creación de consorcios estables. Esta estrategia actualmente se hace imprescindible a la hora de realizar estudios de alta calidad científica que permitan seguir avanzando en el conocimiento de las bases genéticas del ictus tanto en etiología, como en tratamiento y prevención

This article provides an overview of stroke genetics studies ranging from the candidate gene approach to more recent studies by the genome wide association. It highlights the complexity of stroke owing to its different aetiopathogenic mechanisms, the difficulties in studying its genetic component, and the solutions provided to date. The study emphasises the importance of cooperation between the different centres, whether this takes places occasionally or through the creation of lasting consortiums. This strategy is currently essential to the completion of high-quality scientific studies that allow researchers to gain a better knowledge of the genetic component of stroke as it relates to aetiology, treatment, and prevention

Exploring the genetic basis of stroke. Spanish stroke genetics consortium.

This article provides an overview of stroke genetics studies ranging from the candidate gene approach to more recent studies by the genome wide association. It highlights the complexity of stroke owing to its different aetiopathogenic mechanisms, the difficulties in studying its genetic component, and the solutions provided to date. The study emphasises the importance of cooperation between the different centres, whether this takes places occasionally or through the creation of lasting consortiums. This strategy is currently essential to the completion of high-quality scientific studies that allow researchers to gain a better knowledge of the genetic component of stroke as it relates to aetiology, treatment, and prevention.

Update on the Serum Biomarkers and Genetic Factors Associated with Safety and Efficacy of rt-PA Treatment in Acute Stroke Patients.

An accurate understanding of the mechanisms underlying an individual's response to rt-PA treatment is critical to improve stroke patients' management. We thus reviewed the literature in order to identify biochemical and genetic factors that have been associated with safety and efficacy of rt-PA administration after stroke.

No evidence of APP point mutation and locus duplication in individuals with cerebral amyloid angiopathy.

BACKGROUND: Cerebral amyloid angiopathy (CAA) is a well-established cause of lobar intracerebral hemorrhage (ICH). Familial forms of CAA are because of mutations in the gene encoding the beta-amyloid precursor protein (APP) and duplications of this gene can cause early-onset Alzheimer's disease associated with CAA. However, the contribution of APP genetic variants in the development of sporadic CAA remains unknown. METHODS: The presence of genetic variants in the APP was examined in 78 patients with CAA-related ICH by sequencing exons 16 and 17 coding the ß-amyloid protein and analyzing the presence of possible duplications of APP by microsatellite analysis and quantitative PCR. RESULTS: We did not identify any pathogenic mutation or chromosomal duplication of APP. CONCLUSIONS: Our results suggest that APP genetic variants, point mutations and locus duplication, are not a common cause of CAA-related ICH in the Spanish population.

A panel of biomarkers including caspase-3 and D-dimer may differentiate acute stroke from stroke-mimicking conditions in the emergency department.

BACKGROUND AND AIMS: At present, a rapid and widely available diagnostic test for stroke remains elusive. The aim of this study was to examine the predictive value of a panel of blood-borne biochemical markers for stroke diagnosis. DESIGN: Consecutive patients with strokes or stroke-mimicking conditions (mimics) were evaluated within 24 h from symptom onset (915 strokes and 90 mimics). Blood samples were analysed by enzyme-linked immunosorbent assay for C-reactive protein, d-dimer, soluble receptor for advanced glycation end products (sRAGE), metalloproteinase 9 (MMP-9), S100B, brain natriuretic peptide, caspase-3, neurotrophin-3, chimerin and secretagogin. RESULTS: The main independent predictors of stroke versus mimics were caspase-3 >1.96 ng mL(-1) [odds ratio (OR) = 3.32; 95% confidence interval (CI) 1.88-5.88, P < 0.0001], d-dimer >0.27 µg mL(-1) (OR = 2.97; 95% CI 1.72-5.16, P = 0.0001), sRAGE >0.91 ng mL(-1) (OR = 2.19; 95% CI 1.26-3.83, P = 0.006), chimerin <1.11 ng mL(-1) (OR = 0.4; 95% CI 0.19-0.81, P = 0.011), secretagogin <0.24 ng mL(-1) (OR = 0.51; 95% CI 0.27-0.97, P = 0.041) and MMP-9 > 199 ng mL(-1) (OR = 1.66; 95% CI 1.01-2.73, P = 0.046). The model's predictive probability of stroke when the six biomarkers are above/below these cut-off levels was 99.01%. The best combination of biomarkers in the model was caspase-3 and d-dimer. Moreover, a model developed for samples obtained within the first 3 h showed high sensitivity (Se) and specificity (Sp) (threshold at 25th percentile: Se 0.87, Sp 0.55; threshold at 75th percentile: Se 0.28, Sp 0.99). CONCLUSIONS: A combination of biomarkers including caspase-3 and d-dimer appears to be the most promising to achieve a rapid biochemical diagnosis of stroke. If replicated, this approach could be used as a tool for urgent referral of stroke patients to hospitals in which acute treatments are available.

Osteopontin predicts long-term functional outcome among ischemic stroke patients.

Osteopontin (OPN) is a multifunctional protein which has shown neuroprotective properties in animal models of cerebral ischemia. Nevertheless, its role in acute human stroke has not yet been established. Therefore, we aimed to determine human serum OPN level during acute ischemic stroke and its relationship with patient outcome. We measured OPN levels in 178 consecutive patients with a middle cerebral artery (MCA) occlusion who received fibrinolytic therapy and in 40 control subjects. OPN level was determined by an enzyme-linked immunosorbent assay (ELISA). Bad functional outcome was defined by modified Rankin Scale (mRS) score >2 at 3 months after stroke onset. A logistic regression analysis was performed to determine factors that could be independently associated with poor prognosis. OPN levels among stroke patients did not differ from the controls' OPN levels (16.65 vs. 17.83 ng/mL, p = 0.404). Interestingly, OPN level was increased among those patients who showed worse prognosis at 3 months (19.96 vs. 15.48 ng/mL, p = 0.040). In a logistic regression model, an OPN level >27.22 ng/mL was found to be an independent factor for a bad outcome (OR 5.01, 95% CI 1.60-15.72, p = 0.006) after adjusting for potential confounders. Those patients showing higher OPN levels before tPA administration displayed a worse prognosis compared to those with lower OPN levels. Further research is necessary to elucidate the role of OPN in ischemic stroke pathophysiology and validate OPN as a useful tool to predict long-term stroke outcome.

Leukoaraiosis is associated with genes regulating blood-brain barrier homeostasis in ischaemic stroke patients.

BACKGROUND: The biologic agents causing leukoaraiosis are unknown. Our aim was to study the genetic basis of leukoaraiosis. METHODS: We analyzed 212 single nucleotide polymorphisms (SNPs) in 142 patients with ischaemic stroke, generating a total of 30,104 genotypes. Seventy-nine subjects (55.6%) presented leukoaraiosis measured by the Fazekas scale and 69 (48.6%) by ARWMC scale. We analyzed the presence of synergic associations between SNPs using the hfcc software. Finally, functional studies were performed in 56 subjects. The Ingenuity Pathways software (ipa) was used to examine the role of the identified genes. RESULTS: Six SNPs were associated with leukoaraiosis using both measuring scales. After logistic regression adjusted for leukoaraiosis risk factors, the rs2252070 of MMP13 (OR = 4.9, 95%CI: 1.34-17.9, P = 0.016), rs662 of PON1 (OR = 0.37, 95%CI: 0.15-0.87, P = 0.024) and rs1800779 of NOS3 (OR = 3.9, 95%CI: 1.38-11.38, P = 0.01) were independently associated with leukoaraiosis under a dominant/recessive model and the rs2290608 of IL5RA (OR = 0.46, 95%CI: 0.25-0.85, P = 0.013) and rs669 of A2M (OR = 2.5, 95%CI: 1.36-4.83, P = 0.004) under an additive model. Computational analysis showed a synergic association of rs10497212-AA of ITGB6 and rs2290608-GG of IL5RA with leukoaraiosis using both scales. (i) ARWMC (P = 1.3 × 10(-4) ) and (ii) Fazekas (P = 4.5 × 10(-5) ). Functional studies showed that the rs669 SNP was associated with plasma levels of A2M (P = 0.012) and A2M levels with leukoaraiosis in Fazekas scale (P = 0.02). ipa analysis revealed that the genes associated with leukoaraiosis were involved in blood-brain barrier (BBB) homeostasis. CONCLUSIONS: Amongst patients with ischaemic stroke, several genes associated with BBB homeostasis could be involved with a higher risk of leukoaraiosis.

The I/D polymorphism of the ACE1 gene is not associated with ischaemic stroke in Spanish individuals.

BACKGROUND: The angiotensin-converting enzyme 1 (ACE1) gene has been extensively studied in stroke, yet generating conflicting results. The goal of our study was thus to clarify the influence of the ACE1 on the risk of suffering an ischaemic stroke (IS). METHODS: We genotyped the rs4341 (in linkage disequilibrium with the I/D polymorphism) of the ACE1 gene in 531 patients with IS and 549 healthy controls, and the rs1799752 (I/D polymorphism) in a subset of 68 patients with IS and 27 controls. We also performed functional studies by measuring serum ACE protein levels and enzymatic activity in 27 controls, 68 patients with IS at baseline and 35 patients with IS 24 h after onset of stroke symptoms. RESULTS: There was no association of the ACE1 variant with IS, although it affected ACE protein levels (P = 0.001). Indeed, patients with IS showed lower ACE levels than controls in the acute phase (115.9 } 38.9 vs. 174.1 } 56.1 ng/ml, P < 0.001), but not in the chronic phase (168.2 } 51.2, P = 0.673), and ACE protein levels did not differ between IS etiologies. Similar results were found for ACE activity. CONCLUSIONS: The D allele of the ACE1 I/D and ACE protein levels was not associated with a higher risk of IS in Spanish individuals.

PAI-1 4G/5G polymorphism is associated with brain vessel reocclusion after successful fibrinolytic therapy in ischemic stroke patients.

BACKGROUND: Despite t-PA proven benefits related to vessel reopening, up to 13% of stroke patients suffer reocclusions after t-PA. We aimed to analyze whether a functional polymorphism in a fibrinolysis inhibitor gene [plasminogen activator inhibitor-1 (PAI-1)] might be associated with reocclusion rates after stroke thrombolytic therapy. METHODS: 165 patients with ischemic stroke who received t-PA < 3 h were studied. Reocclusion and recanalization was diagnosed by transcranial Doppler. PAI-1 4G/5G polymorphism determination was performed by sequencing. PAI-1 mRNA was studied by real-time PCR analysis. National institutes of health stroke scale (NIHSS) was serially measured since patients arrival to assess the neurological outcome, and modified ranking scale (mRS) at 3rd month was used to evaluate functional outcome following stroke. RESULTS: PAI-1 4G/4G patients had higher reocclusion rates (4G/4G = 12.5% versus other genotypes = 2.7%, p = 0.025). . In a logistic regression, the 4G/4G genotype was the only factor associated with reocclusion (OR = 15.16 95%, CI = 1.4-163.4, p = 0.025). 4G/4G genotype was also associated with poor functional outcome at 3rd month (4G/4G = 4 versus others genotypes = 3, p = 0.017) and with mRNA levels at 12 h post stroke symptoms onset (4G/4G patients = 2.01% versus other genotypes = 0.68%, p = 0.034). CONCLUSIONS: PAI-1 4G/4G genotype is associated with reocclusion rates and poor functional outcome among stroke patients treated with t-PA.

Caspase-3 is related to infarct growth after human ischemic stroke.

Our aim was to investigate caspase-3 plasma levels after stroke, its correlation with infarct expansion and neurological outcome. Caspase-3 plasma levels were determined by ELISA at different time points after stroke in 116 t-PA-treated patients and a control group of 40 healthy controls. Neurological status was evaluated by NIHSS scores and functional outcome by modified Rankin Scale. To assess brain infarct growth, serial brain magnetic resonance imaging scans including diffusion- (DWI) and perfusion-weighted (PWI) images were performed in a subgroup of 58 patients. Plasma caspase-3 levels were higher in stroke patients versus the control group throughout the acute phase of stroke. Furthermore, caspase-3 level at 24h was associated with poorer short- and long-term neurological outcome and positively correlated with infarct growth assessed by diffusion-weighted images. Our data suggest that caspase-3 could be involved in recruitment of ischemic brain tissue being a marker of infarct growth.

[Private mutations in the myophosphorylase gene: the first case in a patient of Latin American descent]. / Mutaciones privadas en el gen de la miofosforilasa: primer caso en un paciente de origen latinoamericano.

INTRODUCTION: McArdle's disease (glycogenoses type V) is a common metabolic myopathy caused by deficient myophosphorylase activity. The disease is due to mutations in the myophosphorylase (PYGM) gene and is present in a large number of countries. CASE REPORT: A 13-year-old male who suffered an episode of muscle pain and offered increased levels of creatinkinase in plasma, myoglobinuria and mild weakness of the proximal muscles, after short but vigorous exercise. The patient was born in Ecuador and was adopted by a Spanish family. The myophosphorylase gene was analysed completely and the patient was found to be a carrier of a missense mutation, a homozygous change where a G is replaced by an A in exon 11, changing a valine for a methionine in codon 456 (V456M). The mutation described above affects an amino acid that is conserved in the enzyme and which was not present in the control population that was studied. CONCLUSIONS: These findings show the presence of McArdle's disease in several ethnic groups and confirm that the ethnic origin of the patient is important when it comes to deciding what mutations should be analysed first in molecular diagnosis studies.

Mutaciones privadas en el gen de la miofosforilasa: primer caso en un paciente de origen latinoamericano / Private mutations in the myophosphorylase gene: The first case in a patient of latin american descent

La enfermedad de McArdle (glicogenosis tipo V) es una miopatía metabólica común causada por unadeficiencia de la actividad de la miofosforilasa. La enfermedad se debe a mutaciones en el gen de la miofosforilasa (PYGM) y está presente en un gran número de países. Caso clínico. Varón de 13 años de edad que sufrió un episodio de dolor muscular y presentó unos niveles elevados de creatincinasa en plasma, mioglobinuria y debilidad de la musculatura proximal moderada, después de un corto pero vigoroso ejercicio. El paciente nació en Ecuador y fue adoptado por una familia española.Se analizó completamente el gen de la miofosforilasa y se encontró que el paciente era portador de una mutación consistente en pérdida de sentido, un cambio homocigótico de una G por una A en el exón 11, cambiando una valina por una metionina en el codón 456 (V456M). La mutación previamente descrita afecta a un aminoácido conservado en la enzima y no estaba presenteen la población control estudiada. Conclusiones. Estos hallazgos demuestran la presencia de la enfermedad de McArdle en varios grupos étnicos y sugiere que el origen étnico del paciente es importante para decidir qué mutaciones deberían analizarse primero en los estudios diagnósticos moleculares (AU)

McArdle's disease (glycogenoses type V) is a common metabolic myopathy caused by deficientmyophosphorylase activity. The disease is due to mutations in the myophosphorylase (PYGM) gene and is present in a large number of countries. Case report. A 13-year-old male who suffered an episode of muscle pain and offered increased levels of creatinkinase in plasma, myoglobinuria and mild weakness of the proximal muscles, after short but vigorous exercise. The patient was born in Ecuador and was adopted by a Spanish family. The myophosphorylase gene was analysed completely andthe patient was found to be a carrier of a missense mutation, a homozygous change where a G is replaced by an A in exon 11, changing a valine for a methionine in codon 456 (V456M). The mutation described above affects an amino acid that is conserved in the enzyme and which was not present in the control population that was studied. Conclusions. These findings show thepresence of McArdle’s disease in several ethnic groups and confirm that the ethnic origin of the patient is important when it comes to deciding what mutations should be analysed first in molecular diagnosis studies (AU)