| 1. |
- Anderson, Christopher D., et al.
(författare)
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Common Variants Within Oxidative Phosphorylation Genes Influence Risk of Ischemic Stroke and Intracerebral Hemorrhage
- 2013
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Ingår i: Stroke: a journal of cerebral circulation. - 1524-4628. ; 44:3, s. 612-619
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Tidskriftsartikel (refereegranskat)abstract
- Background and Purpose-Previous studies demonstrated association between mitochondrial DNA variants and ischemic stroke (IS). We investigated whether variants within a larger set of oxidative phosphorylation (OXPHOS) genes encoded by both autosomal and mitochondrial DNA were associated with risk of IS and, based on our results, extended our investigation to intracerebral hemorrhage (ICH). Methods-This association study used a discovery cohort of 1643 individuals, a validation cohort of 2432 individuals for IS, and an extension cohort of 1476 individuals for ICH. Gene-set enrichment analysis was performed on all structural OXPHOS genes, as well as genes contributing to individual respiratory complexes. Gene-sets passing gene-set enrichment analysis were tested by constructing genetic scores using common variants residing within each gene. Associations between each variant and IS that emerged in the discovery cohort were examined in validation and extension cohorts. Results-IS was associated with genetic risk scores in OXPHOS as a whole (odds ratio [OR], 1.17; P=0.008) and complex I (OR, 1.06; P=0.050). Among IS subtypes, small vessel stroke showed association with OXPHOS (OR, 1.16; P=0.007), complex I (OR, 1.13; P=0.027), and complex IV (OR, 1.14; P=0.018). To further explore this small vessel association, we extended our analysis to ICH, revealing association between deep hemispheric ICH and complex IV (OR, 1.08; P=0.008). Conclusions-This pathway analysis demonstrates association between common genetic variants within OXPHOS genes and stroke. The associations for small vessel stroke and deep ICH suggest that genetic variation in OXPHOS influences small vessel pathobiology. Further studies are needed to identify culprit genetic variants and assess their functional consequences. (Stroke. 2013;44:612-619.)
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| 2. |
- Anderson, Christopher D., et al.
(författare)
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Genetic variants in CETP increase risk of intracerebral hemorrhage
- 2016
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Ingår i: Annals of Neurology. - : Wiley. - 1531-8249 .- 0364-5134. ; 80:5, s. 730-740
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: In observational epidemiologic studies, higher plasma high-density lipoprotein cholesterol (HDL-C) has been associated with increased risk of intracerebral hemorrhage (ICH). DNA sequence variants that decrease cholesteryl ester transfer protein (CETP) gene activity increase plasma HDL-C; as such, medicines that inhibit CETP and raise HDL-C are in clinical development. Here, we test the hypothesis that CETP DNA sequence variants associated with higher HDL-C also increase risk for ICH.METHODS: We performed 2 candidate-gene analyses of CETP. First, we tested individual CETP variants in a discovery cohort of 1,149 ICH cases and 1,238 controls from 3 studies, followed by replication in 1,625 cases and 1,845 controls from 5 studies. Second, we constructed a genetic risk score comprised of 7 independent variants at the CETP locus and tested this score for association with HDL-C as well as ICH risk.RESULTS: Twelve variants within CETP demonstrated nominal association with ICH, with the strongest association at the rs173539 locus (odds ratio [OR] = 1.25, standard error [SE] = 0.06, p = 6.0 × 10(-4) ) with no heterogeneity across studies (I(2) = 0%). This association was replicated in patients of European ancestry (p = 0.03). A genetic score of CETP variants found to increase HDL-C by ∼2.85mg/dl in the Global Lipids Genetics Consortium was strongly associated with ICH risk (OR = 1.86, SE = 0.13, p = 1.39 × 10(-6) ).INTERPRETATION: Genetic variants in CETP associated with increased HDL-C raise the risk of ICH. Given ongoing therapeutic development in CETP inhibition and other HDL-raising strategies, further exploration of potential adverse cerebrovascular outcomes may be warranted. Ann Neurol 2016;80:730-740.
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| 3. |
- Ay, Hakan, et al.
(författare)
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Pathogenic Ischemic Stroke Phenotypes in the NINDS-Stroke Genetics Network
- 2014
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Ingår i: Stroke. - 0039-2499. ; 45:12, s. 3589-3596
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND AND PURPOSE: NINDS (National Institute of Neurological Disorders and Stroke)-SiGN (Stroke Genetics Network) is an international consortium of ischemic stroke studies that aims to generate high-quality phenotype data to identify the genetic basis of pathogenic stroke subtypes. This analysis characterizes the etiopathogenetic basis of ischemic stroke and reliability of stroke classification in the consortium. METHODS: Fifty-two trained and certified adjudicators determined both phenotypic (abnormal test findings categorized in major pathogenic groups without weighting toward the most likely cause) and causative ischemic stroke subtypes in 16954 subjects with imaging-confirmed ischemic stroke from 12 US studies and 11 studies from 8 European countries using the web-based Causative Classification of Stroke System. Classification reliability was assessed with blinded readjudication of 1509 randomly selected cases. RESULTS: The distribution of pathogenic categories varied by study, age, sex, and race (P<0.001 for each). Overall, only 40% to 54% of cases with a given major ischemic stroke pathogenesis (phenotypic subtype) were classified into the same final causative category with high confidence. There was good agreement for both causative (κ 0.72; 95% confidence interval, 0.69-0.75) and phenotypic classifications (κ 0.73; 95% confidence interval, 0.70-0.75). CONCLUSIONS: This study demonstrates that pathogenic subtypes can be determined with good reliability in studies that include investigators with different expertise and background, institutions with different stroke evaluation protocols and geographic location, and patient populations with different epidemiological characteristics. The discordance between phenotypic and causative stroke subtypes highlights the fact that the presence of an abnormality in a patient with stroke does not necessarily mean that it is the cause of stroke.
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| 4. |
- Biffi, Alessandro, et al.
(författare)
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APOE genotype and extent of bleeding and outcome in lobar intracerebral haemorrhage: a genetic association study
- 2011
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Ingår i: Lancet Neurology. - 1474-4465. ; 10:8, s. 702-709
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Tidskriftsartikel (refereegranskat)abstract
- Background Carriers of APOE epsilon 2 and epsilon 4 have an increased risk of intracerebral haemorrhage (ICH) in lobar regions, presumably because of the effects of these gene variants on risk of cerebral amyloid angiopathy. We aimed to assess whether these variants also associate with severity of ICH, in terms of haematoma volume at presentation and subsequent outcome. Methods We investigated the association of APOE epsilon 2 and epsilon 4 with ICH volume and outcomes in patients with primary ICH in three phases: a discovery phase of 865 individuals of European ancestry from the Genetics of Cerebral Hemorrhage on Anticoagulation study, and replication phases of 946 Europeans (replication 1) and 214 African-Americans (replication 2) from an additional six studies. We also assessed the association of APOE variants with ICH volume and outcomes in meta-analyses of results from all three phases, and the association of APOE epsilon 4 with mortality in a further meta-analysis including data from previous reports. Admission ICH volume was quantified on CT scan. We assessed functional outcome (modified Rankin scale score 3-6) and mortality at 90 days. We used linear regression to establish the effect of genotype on haematoma volume and logistic regression to assess the effect on outcome from ICH. Findings For patients with lobar ICH, carriers of the APOE epsilon 2 allele had larger ICH volumes than did non-carriers in the discovery phase (p=2. 5x10(-5)), in both replication phases (p=0.008 in Europeans and p=0.016 in African-Americans), and in the meta-analysis (p=3.2x10(-8)). In the meta-analysis, each copy of APOE epsilon 2 increased haematoma size by a mean of 5.3 mL (95% CI 4.7-5.9; p=0.004). Carriers of APOE epsilon 2 had increased mortality (odds ratio [OR] 1.50, 95% CI 1.23-1.82; p=2.45x10(-5)) and poorer functional outcomes (modified Rankin scale score 3-6; 1-52, 1.25-1.85; p=1.74x10(-5)) compared with non-carriers after lobar ICH. APOE epsilon 4 was not associated with lobar ICH volume, functional outcome, or mortality in the discovery phase, replication phases, or meta-analysis of these three phases; in our further meta-analysis of 2194 patients, this variant did not increase risk of mortality (1.08,0.86-1.36; p=0.52). APOE allele variants were not associated with deep ICH volume, functional outcome, or mortality. Interpretation Vasculopathic changes associated with the APOE epsilon 2 allele might have a role in the severity and clinical course of lobar ICH. Screening of patients who have ICH to identify the epsilon 2 variant might allow identification of those at increased risk of mortality and poor functional outcomes.
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| 5. |
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| 6. |
- Biffi, Alessandro, et al.
(författare)
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Variants at APOE Influence Risk of Deep and Lobar Intracerebral Hemorrhage
- 2010
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Ingår i: Annals of Neurology. - : Wiley. - 1531-8249 .- 0364-5134. ; 68:6, s. 934-943
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Tidskriftsartikel (refereegranskat)abstract
- Objective: Prior studies investigating the association between APOE alleles epsilon 2/epsilon 4 and risk of intracerebral hemorrhage (ICH) have been inconsistent and limited to small sample sizes, and did not account for confounding by population stratification or determine which genetic risk model was best applied. Methods: We performed a large-scale genetic association study of 2189 ICH cases and 4041 controls from 7 cohorts, which were analyzed using additive models for epsilon 2 and epsilon 4. Results were subsequently meta-analyzed using a random effects model. A proportion of the individuals (322 cases, 357 controls) had available genome-wide data to adjust for population stratification. Results: Alleles epsilon 2 and epsilon 4 were associated with lobar ICH at genome-wide significance levels (odds ratio [OR] = 1.82, 95% confidence interval [CI] = 1.50-2.23, p = 6.6 x 10(-10); and OR = 2.20, 95%CI = 1.85-2.63, p = 2.4 x 10(-11), respectively). Restriction of analysis to definite/probable cerebral amyloid angiopathy ICH uncovered a stronger effect. Allele epsilon 4 was also associated with increased risk for deep ICH (OR = 1.21, 95% CI = 1.08-1.36, p = 2.6 x 10(-4)). Risk prediction evaluation identified the additive model as best for describing the effect of APOE genotypes. Interpretation: APOE epsilon 2 and epsilon 4 are independent risk factors for lobar ICH, consistent with their known associations with amyloid biology. In addition, we present preliminary findings on a novel association between APOE epsilon 4 and deep ICH. Finally, we demonstrate that an additive model for these APOE variants is superior to other forms of genetic risk modeling previously applied. ANN NEUROL 2010;68:934-943
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| 7. |
- Bonkhoff, Anna K, et al.
(författare)
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The relevance of rich club regions for functional outcome post-stroke is enhanced in women.
- 2023
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Ingår i: Human brain mapping. - : Wiley. - 1097-0193 .- 1065-9471. ; 44:4, s. 1579-1592
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Tidskriftsartikel (refereegranskat)abstract
- This study aimed to investigate the influence of stroke lesions in predefined highly interconnected (rich-club) brain regions on functional outcome post-stroke, determine their spatial specificity and explore the effects of biological sex on their relevance. We analyzed MRI data recorded at index stroke and ~3-months modified Rankin Scale (mRS) data from patients with acute ischemic stroke enrolled in the multisite MRI-GENIE study. Spatially normalized structural stroke lesions were parcellated into 108 atlas-defined bilateral (sub)cortical brain regions. Unfavorable outcome (mRS>2) was modeled in a Bayesian logistic regression framework. Effects of individual brain regions were captured as two compound effects for (i) six bilateral rich club and (ii) all further non-rich club regions. In spatial specificity analyses, we randomized the split into "rich club" and "non-rich club" regions and compared the effect of the actual rich club regions to the distribution of effects from 1000 combinations of six random regions. In sex-specific analyses, we introduced an additional hierarchical level in our model structure to compare male and female-specific rich club effects. A total of 822 patients (age: 64.7[15.0], 39% women) were analyzed. Rich club regions had substantial relevance in explaining unfavorable functional outcome (mean of posterior distribution: 0.08, area under the curve: 0.8). In particular, the rich club-combination had a higher relevance than 98.4% of random constellations. Rich club regions were substantially more important in explaining long-term outcome in women than in men. All in all, lesions in rich club regions were associated with increased odds of unfavorable outcome. These effects were spatially specific and more pronounced in women.
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| 8. |
- Bretzner, Martin, et al.
(författare)
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Radiomics-Derived Brain Age Predicts Functional Outcome After Acute Ischemic Stroke.
- 2023
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Ingår i: Neurology. - 1526-632X .- 0028-3878. ; 100:8
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Tidskriftsartikel (refereegranskat)abstract
- While chronological age is one of the most influential determinants of poststroke outcomes, little is known of the impact of neuroimaging-derived biological "brain age." We hypothesized that radiomics analyses of T2-FLAIR images texture would provide brain age estimates and that advanced brain age of patients with stroke will be associated with cardiovascular risk factors and worse functional outcomes.We extracted radiomics from T2-FLAIR images acquired during acute stroke clinical evaluation. Brain age was determined from brain parenchyma radiomics using an ElasticNet linear regression model. Subsequently, relative brain age (RBA), which expresses brain age in comparison with chronological age-matched peers, was estimated. Finally, we built a linear regression model of RBA using clinical cardiovascular characteristics as inputs and a logistic regression model of favorable functional outcomes taking RBA as input.We reviewed 4,163 patients from a large multisite ischemic stroke cohort (mean age = 62.8 years, 42.0% female patients). T2-FLAIR radiomics predicted chronological ages (mean absolute error = 6.9 years, r = 0.81). After adjustment for covariates, RBA was higher and therefore described older-appearing brains in patients with hypertension, diabetes mellitus, a history of smoking, and a history of a prior stroke. In multivariate analyses, age, RBA, NIHSS, and a history of prior stroke were all significantly associated with functional outcome (respective adjusted odds ratios: 0.58, 0.76, 0.48, 0.55; all p-values < 0.001). Moreover, the negative effect of RBA on outcome was especially pronounced in minor strokes.T2-FLAIR radiomics can be used to predict brain age and derive RBA. Older-appearing brains, characterized by a higher RBA, reflect cardiovascular risk factor accumulation and are linked to worse outcomes after stroke.
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| 9. |
- Carrera, Caty, et al.
(författare)
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Validation of a clinical-genetics score to predict hemorrhagic transformations after rtPA.
- 2019
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Ingår i: Neurology. - 1526-632X. ; 93:9
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Tidskriftsartikel (refereegranskat)abstract
- To validate the Genot-PA score, a clinical-genetic logistic regression score that stratifies the thrombolytic therapy safety, in a new cohort of patients with stroke.We enrolled 1,482 recombinant tissue plasminogen activator (rtPA)-treated patients with stroke in Spain and Finland from 2003 to 2016. Cohorts were analyzed on the basis of ethnicity and therapy: Spanish patients treated with IV rtPA within 4.5 hours of onset (cohort A and B) or rtPA in combination with mechanical thrombectomy within 6 hours of onset (cohort C) and Finnish participants treated with IV rtPA within 4.5 hours of onset (cohort D). The Genot-PA score was calculated, and hemorrhagic transformation (HT) and parenchymal hematoma (PH) risks were determined for each score stratum.Genot-PA score was tested in 1,324 (cohort A, n = 726; B, n = 334; C, n = 54; and D, n = 210) patients who had enough information to complete the score. Of these, 213 (16.1%) participants developed HT and 85 (6.4%) developed PH. In cohorts A, B, and D, HT occurrence was predicted by the score (p = 2.02 × 10-6, p = 0.023, p = 0.033); PH prediction was associated in cohorts A through C (p = 0.012, p = 0.034, p = 5.32 × 10-4). Increased frequency of PH events from the lowest to the highest risk group was found (cohort A 4%-15.7%, cohort B 1.5%-18.2%, cohort C 0%-100%). The best odds ratio for PH prediction in the highest-risk group was obtained in cohort A (odds ratio 5.16, 95% confidence interval 1.46-18.08, p = 0.009).The Genot-PA score predicts HT in patients with stroke treated with IV rtPA. Moreover, in an exploratory study, the score was associated with PH risk in mechanical thrombectomy-treated patients.
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| 10. |
- Chung, Jaeyoon, et al.
(författare)
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Genome-wide association study of cerebral small vessel disease reveals established and novel loci
- 2019
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Ingår i: Brain : a journal of neurology. - : Oxford University Press (OUP). - 1460-2156. ; 142:10, s. 3176-3189
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Tidskriftsartikel (refereegranskat)abstract
- Intracerebral haemorrhage and small vessel ischaemic stroke (SVS) are the most acute manifestations of cerebral small vessel disease, with no established preventive approaches beyond hypertension management. Combined genome-wide association study (GWAS) of these two correlated diseases may improve statistical power to detect novel genetic factors for cerebral small vessel disease, elucidating underlying disease mechanisms that may form the basis for future treatments. Because intracerebral haemorrhage location is an adequate surrogate for distinct histopathological variants of cerebral small vessel disease (lobar for cerebral amyloid angiopathy and non-lobar for arteriolosclerosis), we performed GWAS of intracerebral haemorrhage by location in 1813 subjects (755 lobar and 1005 non-lobar) and 1711 stroke-free control subjects. Intracerebral haemorrhage GWAS results by location were meta-analysed with GWAS results for SVS from MEGASTROKE, using 'Multi-Trait Analysis of GWAS' (MTAG) to integrate summary data across traits and generate combined effect estimates. After combining intracerebral haemorrhage and SVS datasets, our sample size included 241 024 participants (6255 intracerebral haemorrhage or SVS cases and 233 058 control subjects). Genome-wide significant associations were observed for non-lobar intracerebral haemorrhage enhanced by SVS with rs2758605 [MTAG P-value (P) = 2.6 × 10-8] at 1q22; rs72932727 (P = 1.7 × 10-8) at 2q33; and rs9515201 (P = 5.3 × 10-10) at 13q34. In the GTEx gene expression library, rs2758605 (1q22), rs72932727 (2q33) and rs9515201 (13q34) are significant cis-eQTLs for PMF1 (P = 1 × 10-4 in tibial nerve), NBEAL1, FAM117B and CARF (P < 2.1 × 10-7 in arteries) and COL4A2 and COL4A1 (P < 0.01 in brain putamen), respectively. Leveraging S-PrediXcan for gene-based association testing with the predicted expression models in tissues related with nerve, artery, and non-lobar brain, we found that experiment-wide significant (P < 8.5 × 10-7) associations at three genes at 2q33 including NBEAL1, FAM117B and WDR12 and genome-wide significant associations at two genes including ICA1L at 2q33 and ZCCHC14 at 16q24. Brain cell-type specific expression profiling libraries reveal that SEMA4A, SLC25A44 and PMF1 at 1q22 and COL4A1 and COL4A2 at 13q34 were mainly expressed in endothelial cells, while the genes at 2q33 (FAM117B, CARF and NBEAL1) were expressed in various cell types including astrocytes, oligodendrocytes and neurons. Our cross-phenotype genetic study of intracerebral haemorrhage and SVS demonstrates novel genome-wide associations for non-lobar intracerebral haemorrhage at 2q33 and 13q34. Our replication of the 1q22 locus previous seen in traditional GWAS of intracerebral haemorrhage, as well as the rediscovery of 13q34, which had previously been reported in candidate gene studies with other cerebral small vessel disease-related traits strengthens the credibility of applying this novel genome-wide approach across intracerebral haemorrhage and SVS.
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| 11. |
- Devan, William J., et al.
(författare)
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Heritability Estimates Identify a Substantial Genetic Contribution to Risk and Outcome of Intracerebral Hemorrhage
- 2013
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Ingår i: Stroke: a journal of cerebral circulation. - 1524-4628. ; 44:6, s. 1578-1583
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Tidskriftsartikel (refereegranskat)abstract
- Background and Purpose-Previous studies suggest that genetic variation plays a substantial role in occurrence and evolution of intracerebral hemorrhage (ICH). Genetic contribution to disease can be determined by calculating heritability using family-based data, but such an approach is impractical for ICH because of lack of large pedigree-based studies. However, a novel analytic tool based on genome-wide data allows heritability estimation from unrelated subjects. We sought to apply this method to provide heritability estimates for ICH risk, severity, and outcome. Methods-We analyzed genome-wide genotype data for 791 ICH cases and 876 controls, and determined heritability as the proportion of variation in phenotype attributable to captured genetic variants. Contribution to heritability was separately estimated for the APOE (encoding apolipoprotein E) gene, an established genetic risk factor, and for the rest of the genome. Analyzed phenotypes included ICH risk, admission hematoma volume, and 90-day mortality. Results-ICH risk heritability was estimated at 29% (SE, 11%) for non-APOE loci and at 15% (SE, 10%) for APOE. Heritability for 90-day ICH mortality was 41% for non-APOE loci and 10% (SE, 9%) for APOE. Genetic influence on hematoma volume was also substantial: admission volume heritability was estimated at 60% (SE, 70%) for non-APOE loci and at 12% (SE, 4%) for APOE. Conclusions-Genetic variation plays a substantial role in ICH risk, outcome, and hematoma volume. Previously reported risk variants account for only a portion of inherited genetic influence on ICH pathophysiology, pointing to additional loci yet to be identified.
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| 12. |
- Falcone, Guido J., et al.
(författare)
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Burden of Risk Alleles for Hypertension Increases Risk of Intracerebral Hemorrhage
- 2012
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Ingår i: Stroke: a journal of cerebral circulation. - 1524-4628. ; 43:11, s. 2877-2883
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Tidskriftsartikel (refereegranskat)abstract
- Background and Purpose-Genetic variation influences risk of intracerebral hemorrhage (ICH). Hypertension (HTN) is a potent risk factor for ICH and several common genetic variants (single nucleotide polymorphisms [SNPs]) associated with blood pressure levels have been identified. We sought to determine whether the cumulative burden of blood pressure-related SNPs is associated with risk of ICH and pre-ICH diagnosis of HTN. Methods-We conducted a prospective multicenter case-control study in 2272 subjects of European ancestry (1025 cases and 1247 control subjects). Thirty-nine SNPs reported to be associated with blood pressure levels were identified from the National Human Genome Research Institute genomewide association study catalog. Single-SNP association analyses were performed for the outcomes ICH and pre-ICH HTN. Subsequently, weighted and unweighted genetic risk scores were constructed using these SNPs and entered as the independent variable in logistic regression models with ICH and pre-ICH HTN as the dependent variables. Results-No single SNP was associated with either ICH or pre-ICH HTN. The blood pressure-based unweighted genetic risk score was associated with risk of ICH (OR, 1.11; 95% CI, 1.02-1.21; P=0.01) and the subset of ICH in deep regions (OR, 1.18; 95% CI, 1.07-1.30; P=0.001), but not with the subset of lobar ICH. The score was associated with a history of HTN among control subjects (OR, 1.17; 95% CI, 1.04-1.31; P=0.009) and ICH cases (OR, 1.15; 95% CI, 1.01-1.31; P=0.04). Similar results were obtained when using a weighted score. Conclusion-Increasing numbers of high blood pressure-related alleles are associated with increased risk of deep ICH as well as with clinically identified HTN. (Stroke. 2012; 43: 2877-2883.)
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| 13. |
- Giese, Anne Katrin, et al.
(författare)
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Design and rationale for examining neuroimaging genetics in ischemic stroke : The MRI-GENIE study
- 2017
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Ingår i: Neurology: Genetics. - 2376-7839. ; 3:5
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Tidskriftsartikel (refereegranskat)abstract
- Objective: To describe the design and rationale for the genetic analysis of acute and chronic cerebrovascular neuroimaging phenotypes detected on clinical MRI in patients with acute ischemic stroke (AIS) within the scope of the MRI-GENetics Interface Exploration (MRI-GENIE) study. Methods: MRI-GENIE capitalizes on the existing infrastructure of the Stroke Genetics Network (SiGN). In total, 12 international SiGN sites contributedMRIs of 3,301 patients with AIS. Detailed clinical phenotyping with the web-based Causative Classification of Stroke (CCS) system and genome-wide genotyping data were available for all participants. Neuroimaging analyses include themanual and automated assessments of established MRI markers. A high-throughputMRI analysis pipeline for the automated assessment of cerebrovascular lesions on clinical scans will be developed in a subset of scans for both acute and chronic lesions, validated against gold standard, and applied to all available scans. The extracted neuroimaging phenotypes will improve characterization of acute and chronic cerebrovascular lesions in ischemic stroke, including CCS subtypes, and their effect on functional outcomes after stroke. Moreover, genetic testing will uncover variants associated with acute and chronic MRI manifestations of cerebrovascular disease.Conclusions: The MRI-GENIE study aims to develop, validate, and distribute the MRI analysis platform for scans acquired as part of clinical care for patients with AIS, which will lead to (1) novel genetic discoveries in ischemic stroke, (2) strategies for personalized stroke risk assessment, and (3) personalized stroke outcome assessment.
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| 14. |
- Jiménez-Balado, Joan, et al.
(författare)
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DNA methylation and stroke prognosis : an epigenome-wide association study
- 2024
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Ingår i: Clinical Epigenetics. - : BioMed Central (BMC). - 1868-7083. ; 16:1
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Tidskriftsartikel (refereegranskat)abstract
- Background and aimsStroke is the leading cause of adult-onset disability. Although clinical factors influence stroke outcome, there is a significant variability among individuals that may be attributed to genetics and epigenetics, including DNA methylation (DNAm). We aimed to study the association between DNAm and stroke prognosis.Methods and resultsTo that aim, we conducted a two-phase study (discovery-replication and meta-analysis) in Caucasian patients with ischemic stroke from two independent centers (BasicMar [discovery, N = 316] and St. Pau [replication, N = 92]). Functional outcome was assessed using the modified Rankin Scale (mRS) at three months after stroke, being poor outcome defined as mRS > 2. DNAm was determined using the 450K and EPIC BeadChips in whole-blood samples collected within the first 24 h. We searched for differentially methylated positions (DMPs) in 370,344 CpGs, and candidates below p-value < 10–5 were subsequently tested in the replication cohort. We then meta-analyzed DMP results from both cohorts and used them to identify differentially methylated regions (DMRs).After doing the epigenome-wide association study, we found 29 DMPs at p-value < 10–5 and one of them was replicated: cg24391982, annotated to thrombospondin-2 (THBS2) gene (p-valuediscovery = 1.54·10–6; p-valuereplication = 9.17·10–4; p-valuemeta-analysis = 6.39·10–9). Besides, four DMRs were identified in patients with poor outcome annotated to zinc finger protein 57 homolog (ZFP57), Arachidonate 12-Lipoxygenase 12S Type (ALOX12), ABI Family Member 3 (ABI3) and Allantoicase (ALLC) genes (p-value < 1·10–9 in all cases).DiscussionPatients with poor outcome showed a DMP at THBS2 and four DMRs annotated to ZFP57, ALOX12, ABI3 and ALLC genes. This suggests an association between stroke outcome and DNAm, which may help identify new stroke recovery mechanisms.
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| 15. |
- Johansson, Elias, et al.
(författare)
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Recurrent stroke in symptomatic carotid stenosis awaiting revascularization : A pooled analysis
- 2016
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Ingår i: Neurology. - : Wolters Kluwer. - 0028-3878 .- 1526-632X. ; 86:6, s. 498-504
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Tidskriftsartikel (refereegranskat)abstract
- Objective: We aimed to quantify the risk and predictors of ipsilateral ischemic stroke in patients with symptomatic carotid stenosis awaiting revascularization (carotid endarterectomy [CEA] or carotid artery stenting) by pooling individual patient data from recent prospective studies with high rates of treatment with modern stroke prevention medications.Methods: Data were included from 2 prospective hospital-based registries (Umea, Barcelona) and one prospective population-based study (Dublin). Patients with symptomatic 50%-99% carotid stenosis eligible for carotid revascularization were included and followed for early recurrent ipsilateral stroke or retinal artery occlusion (RAO).Results: Of 607 patients with symptomatic 50%-99% carotid stenosis, 377 met prespecified inclusion criteria. Ipsilateral recurrent ischemic stroke/RAO risk pre-revascularization was 2.7% (1 day), 5.3% (3 days), 11.5% (14 days), and 18.8% (90 days). On bivariate analysis, presentation with a cerebral vs ocular event was associated with higher recurrent stroke risk (log-rank p = 0.04). On multivariable Cox regression, recurrence was associated with older age (adjusted hazard ratio [HR] per 10-year increase 1.5, p = 0.02) with a strong trend for association with cerebral (stroke/TIA) vs ocular symptoms (adjusted HR 2.7, p = 0.06), but not degree of stenosis, smoking, vascular risk factors, or medications.Conclusions: We found high risk of recurrent ipsilateral ischemic events within the 14-day time period currently recommended for CEA. Randomized trials are needed to determine the benefits and safety of urgent vs subacute carotid revascularization within 14 days after symptom onset.
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| 16. |
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| 17. |
- Marini, Sandro, et al.
(författare)
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17p12 Influences Hematoma Volume and Outcome in Spontaneous Intracerebral Hemorrhage
- 2018
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Ingår i: Stroke. - 0039-2499. ; 49:7, s. 1618-1625
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Tidskriftsartikel (refereegranskat)abstract
- Background and Purpose-Hematoma volume is an important determinant of clinical outcome in spontaneous intracerebral hemorrhage (ICH). We performed a genome-wide association study (GWAS) of hematoma volume with the aim of identifying novel biological pathways involved in the pathophysiology of primary brain injury in ICH. Methods-We conducted a 2-stage (discovery and replication) case-only genome-wide association study in patients with ICH of European ancestry. We utilized the admission head computed tomography to calculate hematoma volume via semiautomated computer-Assisted technique. After quality control and imputation, 7 million genetic variants were available for association testing with ICH volume, which was performed separately in lobar and nonlobar ICH cases using linear regression. Signals with P<5×10- 8 were pursued in replication and tested for association with admission Glasgow coma scale and 3-month post-ICH dichotomized (0-2 versus 3-6) modified Rankin Scale using ordinal and logistic regression, respectively. Results-The discovery phase included 394 ICH cases (228 lobar and 166 nonlobar) and identified 2 susceptibility loci: A genomic region on 22q13 encompassing PARVB (top single-nucleotide polymorphism rs9614326: β, 1.84; SE, 0.32; P=4.4×10-8) for lobar ICH volume and an intergenic region overlying numerous copy number variants on 17p12 (top single-nucleotide polymorphism rs11655160: β, 0.95; SE, 0.17; P=4.3×10-8) for nonlobar ICH volume. The replication included 240 ICH cases (71 lobar and 169 nonlobar) and corroborated the association for 17p12 (P=0.04; meta-Analysis P=2.5×10-9; heterogeneity, P=0.16) but not for 22q13 (P=0.49). In multivariable analysis, rs11655160 was also associated with lower admission Glasgow coma scale (odds ratio, 0.17; P=0.004) and increased risk of poor 3-month modified Rankin Scale (odds ratio, 1.94; P=0.045). Conclusions-We identified 17p12 as a novel susceptibility risk locus for hematoma volume, clinical severity, and functional outcome in nonlobar ICH. Replication in other ethnicities and follow-up translational studies are needed to elucidate the mechanism mediating the observed association.
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| 18. |
- Ntaios, George, et al.
(författare)
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A tool to identify patients with embolic stroke of undetermined source at high recurrence risk.
- 2019
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Ingår i: Neurology. - 1526-632X. ; 93:23
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Tidskriftsartikel (refereegranskat)abstract
- A tool to stratify the risk of stroke recurrence in patients with embolic stroke of undetermined source (ESUS) could be useful in research and clinical practice. We aimed to determine whether a score can be developed and externally validated for the identification of patients with ESUS at high risk for stroke recurrence.We pooled the data of all consecutive patients with ESUS from 11 prospective stroke registries. We performed multivariable Cox regression analysis to identify predictors of stroke recurrence. Based on the coefficient of each covariate of the fitted multivariable model, we generated an integer-based point scoring system. We validated the score externally assessing its discrimination and calibration.In 3 registries (884 patients) that were used as the derivation cohort, age, leukoaraiosis, and multiterritorial infarct were identified as independent predictors of stroke recurrence and were included in the final score, which assigns 1 point per every decade after 35 years of age, 2 points for leukoaraiosis, and 3 points for multiterritorial infarcts (acute or old nonlacunar). The rate of stroke recurrence was 2.1 per 100 patient-years (95% confidence interval [CI] 1.44-3.06) in patients with a score of 0-4 (low risk), 3.74 (95% CI 2.77-5.04) in patients with a score of 5-6 (intermediate risk), and 8.23 (95% CI 5.99-11.3) in patients with a score of 7-12 (high risk). Compared to low-risk patients, the risk of stroke recurrence was significantly higher in intermediate-risk (hazard ratio [HR] 1.78, 95% CI 1.1-2.88) and high-risk patients (HR 4.67, 95% CI 2.83-7.7). The score was well-calibrated in both derivation and external validation cohorts (8 registries, 820 patients) (Hosmer-Lemeshow test χ2: 12.1 [p = 0.357] and χ2: 21.7 [p = 0.753], respectively). The area under the curve of the score was 0.63 (95% CI 0.58-0.68) and 0.60 (95% CI 0.54-0.66), respectively.The proposed score can assist in the identification of patients with ESUS at high risk for stroke recurrence.
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| 19. |
- Phuah, Chia-Ling, et al.
(författare)
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Genetic variants influencing elevated myeloperoxidase levels increase risk of stroke
- 2017
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Ingår i: Brain. - : Oxford University Press (OUP). - 0006-8950 .- 1460-2156. ; 140:10, s. 2663-2672
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Tidskriftsartikel (refereegranskat)abstract
- Primary intracerebral haemorrhage and lacunar ischaemic stroke are acute manifestations of progressive cerebral microvascular disease. Current paradigms suggest atherosclerosis is a chronic, dynamic, inflammatory condition precipitated in response to endothelial injury from various environmental challenges. Myeloperoxidase plays a central role in initiation and progression of vascular inflammation, but prior studies linking myeloperoxidase with stroke risk have been inconclusive. We hypothesized that genetic determinants of myeloperoxidase levels influence the development of vascular instability, leading to increased primary intracerebral haemorrhage and lacunar stroke risk. We used a discovery cohort of 1409 primary intracerebral haemorrhage cases and 1624 controls from three studies, an extension cohort of 12 577 ischaemic stroke cases and 25 643 controls from NINDSSiGN, and a validation cohort of 10 307 ischaemic stroke cases and 29 326 controls from METASTROKE Consortium with genome-wide genotyping to test this hypothesis. A genetic risk score reflecting elevated myeloperoxidase levels was constructed from 15 common single nucleotide polymorphisms identified from prior genome-wide studies of circulating myeloperoxidase levels (P55 - 10 6). This genetic risk score was used as the independent variable in multivariable regression models for association with primary intracerebral haemorrhage and ischaemic stroke subtypes. We used fixed effects meta-analyses to pool estimates across studies. We also used Cox regression models in a prospective cohort of 174 primary intracerebral haemorrhage survivors for association with intracerebral haemorrhage recurrence. We present effects of myeloperoxidase elevating single nucleotide polymorphisms on stroke risk per risk allele, corresponding to a one allele increase in the myeloperoxidase increasing genetic risk score. Genetic determinants of elevated circulating myeloperoxidase levels were associated with both primary intracerebral haemorrhage risk (odds ratio, 1.07, P = 0.04) and recurrent intracerebral haemorrhage risk (hazards ratio, 1.45, P = 0.006). In analysis of ischaemic stroke subtypes, the myeloperoxidase increasing genetic risk score was strongly associated with lacunar subtype only (odds ratio, 1.05, P = 0.0012). These results, demonstrating that common genetic variants that increase myeloperoxidase levels increase risk of primary intracerebral haemorrhage and lacunar stroke, directly implicate the myeloperoxidase pathway in the pathogenesis of cerebral small vessel disease. Because genetic variants are not influenced by environmental exposures, these results provide new support for a causal rather than bystander role for myeloperoxidase in the progression of cerebrovascular disease. Furthermore, these results support a rationale for chronic inflammation as a potential modifiable stroke risk mechanism, and suggest that immune-targeted therapies could be useful for treatment and prevention of cerebrovascular disease.
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| 20. |
- Woo, Daniel, et al.
(författare)
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Meta-Analysis of Genome-Wide Association Studies Identifies 1q22 as a Susceptibility Locus for Intracerebral Hemorrhage.
- 2014
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Ingår i: American Journal of Human Genetics. - : Elsevier BV. - 0002-9297. ; 94:4, s. 511-521
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Tidskriftsartikel (refereegranskat)abstract
- Intracerebral hemorrhage (ICH) is the stroke subtype with the worst prognosis and has no established acute treatment. ICH is classified as lobar or nonlobar based on the location of ruptured blood vessels within the brain. These different locations also signal different underlying vascular pathologies. Heritability estimates indicate a substantial genetic contribution to risk of ICH in both locations. We report a genome-wide association study of this condition that meta-analyzed data from six studies that enrolled individuals of European ancestry. Case subjects were ascertained by neurologists blinded to genotype data and classified as lobar or nonlobar based on brain computed tomography. ICH-free control subjects were sampled from ambulatory clinics or random digit dialing. Replication of signals identified in the discovery cohort with p < 1 × 10(-6) was pursued in an independent multiethnic sample utilizing both direct and genome-wide genotyping. The discovery phase included a case cohort of 1,545 individuals (664 lobar and 881 nonlobar cases) and a control cohort of 1,481 individuals and identified two susceptibility loci: for lobar ICH, chromosomal region 12q21.1 (rs11179580, odds ratio [OR] = 1.56, p = 7.0 × 10(-8)); and for nonlobar ICH, chromosomal region 1q22 (rs2984613, OR = 1.44, p = 1.6 × 10(-8)). The replication included a case cohort of 1,681 individuals (484 lobar and 1,194 nonlobar cases) and a control cohort of 2,261 individuals and corroborated the association for 1q22 (p = 6.5 × 10(-4); meta-analysis p = 2.2 × 10(-10)) but not for 12q21.1 (p = 0.55; meta-analysis p = 2.6 × 10(-5)). These results demonstrate biological heterogeneity across ICH subtypes and highlight the importance of ascertaining ICH cases accordingly.
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| 21. |
- Wu, Ona, et al.
(författare)
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Big Data Approaches to Phenotyping Acute Ischemic Stroke Using Automated Lesion Segmentation of Multi-Center Magnetic Resonance Imaging Data
- 2019
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Ingår i: Stroke. - 1524-4628. ; 50:7, s. 1734-1741
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Tidskriftsartikel (refereegranskat)abstract
- Background and Purpose- We evaluated deep learning algorithms' segmentation of acute ischemic lesions on heterogeneous multi-center clinical diffusion-weighted magnetic resonance imaging (MRI) data sets and explored the potential role of this tool for phenotyping acute ischemic stroke. Methods- Ischemic stroke data sets from the MRI-GENIE (MRI-Genetics Interface Exploration) repository consisting of 12 international genetic research centers were retrospectively analyzed using an automated deep learning segmentation algorithm consisting of an ensemble of 3-dimensional convolutional neural networks. Three ensembles were trained using data from the following: (1) 267 patients from an independent single-center cohort, (2) 267 patients from MRI-GENIE, and (3) mixture of (1) and (2). The algorithms' performances were compared against manual outlines from a separate 383 patient subset from MRI-GENIE. Univariable and multivariable logistic regression with respect to demographics, stroke subtypes, and vascular risk factors were performed to identify phenotypes associated with large acute diffusion-weighted MRI volumes and greater stroke severity in 2770 MRI-GENIE patients. Stroke topography was investigated. Results- The ensemble consisting of a mixture of MRI-GENIE and single-center convolutional neural networks performed best. Subset analysis comparing automated and manual lesion volumes in 383 patients found excellent correlation (ρ=0.92; P<0.0001). Median (interquartile range) diffusion-weighted MRI lesion volumes from 2770 patients were 3.7 cm3 (0.9-16.6 cm3). Patients with small artery occlusion stroke subtype had smaller lesion volumes ( P<0.0001) and different topography compared with other stroke subtypes. Conclusions- Automated accurate clinical diffusion-weighted MRI lesion segmentation using deep learning algorithms trained with multi-center and diverse data is feasible. Both lesion volume and topography can provide insight into stroke subtypes with sufficient sample size from big heterogeneous multi-center clinical imaging phenotype data sets.
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