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- 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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| 2. |
- Rannikmäe, Kristiina, et al.
(författare)
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COL4A2 is associated with lacunar ischemic stroke and deep ICH: Meta-analyses among 21,500 cases and 40,600 controls.
- 2017
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Ingår i: Neurology. - 1526-632X .- 0028-3878. ; 89:17, s. 1829-1839
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Tidskriftsartikel (refereegranskat)abstract
- To determine whether common variants in familial cerebral small vessel disease (SVD) genes confer risk of sporadic cerebral SVD.We meta-analyzed genotype data from individuals of European ancestry to determine associations of common single nucleotide polymorphisms (SNPs) in 6 familial cerebral SVD genes (COL4A1, COL4A2, NOTCH3, HTRA1, TREX1, and CECR1) with intracerebral hemorrhage (ICH) (deep, lobar, all; 1,878 cases, 2,830 controls) and ischemic stroke (IS) (lacunar, cardioembolic, large vessel disease, all; 19,569 cases, 37,853 controls). We applied data quality filters and set statistical significance thresholds accounting for linkage disequilibrium and multiple testing.A locus in COL4A2 was associated (significance threshold p < 3.5 × 10-4) with both lacunar IS (lead SNP rs9515201: odds ratio [OR] 1.17, 95% confidence interval [CI] 1.11-1.24, p = 6.62 × 10-8) and deep ICH (lead SNP rs4771674: OR 1.28, 95% CI 1.13-1.44, p = 5.76 × 10-5). A SNP in HTRA1 was associated (significance threshold p < 5.5 × 10-4) with lacunar IS (rs79043147: OR 1.23, 95% CI 1.10-1.37, p = 1.90 × 10-4) and less robustly with deep ICH. There was no clear evidence for association of common variants in either COL4A2 or HTRA1 with non-SVD strokes or in any of the other genes with any stroke phenotype.These results provide evidence of shared genetic determinants and suggest common pathophysiologic mechanisms of distinct ischemic and hemorrhagic cerebral SVD stroke phenotypes, offering new insights into the causal mechanisms of cerebral SVD.
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