Genetic and Hemostatic Risk Factors for Stroke

Cardiovascular disorders are the main causes of death worldwide, with stroke accounting for 9-10% of all deaths1,2. Moreover, stroke is the most frequent cause of disability in the western world3. In the Netherlands alone, over 39,000 persons are admitted to hospitals with stroke each year4. There are two main types of stroke; ischemic stroke (occurring in about 80% of cases) and hemorrhagic stroke (20%). Hemorrhagic strokes can be further subdivided into intracerebral hemorrhage (15%) and subarachnoid hemorrhage (5%). In ischemic stroke, an artery or arteriole is blocked by thrombosis or an embolus, impeding blood flow to a part of the brain and causing tissue damage in the supplied territory. Intracerebral hemorrhage, on the other hand, results from rupture of a blood vessel, leading to the formation of a hematoma in the brain parenchyma. Although ischemic stroke and intracerebral hemorrhage are in a way opposite, they share several risk factors such as coagulation abnormalities, atherosclerosis and cardiac disorders. It is known that individuals with a positive family history for cardiovascular diseases have a higher risk of stroke. This may be explained by shared environmental risk factors and socioeconomic status, similar dietary habits (e.g. high cholesterol intake), but most obviously by common genetic material. The observation of increased risk of cerebrovascular disease in first degree relatives of stroke patients has fostered the notion of a genetic component of stroke. Until a few years ago, knowledge of the genetic background of stroke risk was limited, and mostly derived from small, family-based linkage studies5. Since the beginning of this millennium, however, advances in genomics have skyrocketed, paving the way for very large genetic studies6. New genetic risk factors are discovered continuously, rapidly increasing our knowledge on the genetics of complex diseases. Also in stroke, these studies are being undertaken to gain more insight in the role of genetic factors in stroke etiology

Variation in the C-reactive protein gene is associated with serum levels of CRP in patients with acute ischemic stroke

Background and Purpose: Elevated levels of C-reactive protein (CRP) are found in up to three quarters of patients with acute ischemic stroke and are associated with poor outcome. We investigated whether haplotypes representing common variations in the CRP gene are associated with levels of CRP in patients with acute ischemic stroke. Methods: We included 185 patients with ischemic stroke in whom CRP was measured within 24 h of symptom onset. Common haplotypes within the CRP gene were determined by 3 genotype-tagging single-nucleotide polymorphisms (SNPs). Results: Four haplotypes with frequencies >5% covered 99.2% of the genetic variation. Haplotype 4 (CCG, frequency 8.3%) was associated with a 20.6 mg/l (95% CI, 9.8-30.4) stronger increase in CRP level as compared with haplotype 1 (CTC, frequency 33.7%). Conclusion: Variation in the CRP gene is associated with levels of CRP in acute ischemic stroke. Copyrigh

γ/total fibrinogen ratio is associated with short-term outcome in ischaemic stroke

Fibrinogen γ' (γ') is a natural isoform of fibrinogen, and alters the rate of formation and the properties of clots. It could therefore affect outcome after ischaemic stroke. The prognostic significance of γ' fibrinogen levels is, however, still unclear. It was the objective of this study to assess levels of γ' in ischaemic stroke, and its association with short-term outcome. We included 200 ischaemic stroke patients and 156 control persons. Total fibrinogen and γ' levels were measured; outcome at discharge was assessed by means of the modified Rankin Scale score (defined as unfavourable when >2). We compared levels between patients and controls using multiple linear regression analysis, and logistic regression analysis was used to assess the relationship between levels and outcome. All analyses were adjusted for age and sex. Mean γ' levels were significantly higher in patients with ischaemic stroke than in controls (0.37 vs. 0.32 g/l, p<0.001), and patients also had a higher γ'/total fibrinogen ratio (0.102 vs. 0.096, p=0.19). The γ'/total fibrinogen ratio is associated with unfavourable outcome in patients with ischaemic stroke (odds ratio per unit increase of γ'/total fibrinogen ratio 1.27, 95% confidence interval 1.09-1.47). Our study shows that patients with ischaemic stroke have increased levels of fibrinogen γ' and suggests a trend towards an increased γ'/total fibrinogen ratio in ischaemic stroke. Increased fibrinogen γ' relative to total fibrinogen levels are associated with unfavourable outcome in the early phase after stroke

Prevalence of Bladder and Bowel Dysfunction in Duchenne Muscular Dystrophy Using the Childhood Bladder and Bowel Dysfunction Questionnaire

Introduction: Lower urinary tract symptoms (LUTS) and gastrointestinal (GI) problems are common in Duchenne muscular dystrophy (DMD), but not systematically assessed in regular care. We aimed to determine the prevalence of bladder and bowel dysfunction (BBD) in DMD patients compared with healthy controls (HC). Methods: The Childhood Bladder and Bowel Dysfunction Questionnaire (CBBDQ) based on the International Rome III criteria and the International Children's Continence Society was filled out by 57 DMD patients and 56 HC. Additionally, possible associations of BBD with, for example, medication use or quality of life were evaluated in an additional questionnaire developed by experts. Results: In 74% of patients versus 56% of HC >= 1 LUTS (n.s.) were reported, 68% of patients versus 39% of HC reported >= 1 bowel symptom (p = 0.002) and 53% of patients versus 30% of HC reported combined LUTS and bowel symptoms (p = 0.019). A negative impact of BBD on daily life functioning was reported by 42% of patients. Conclusions: These data underscore that standard screening for BBD is needed and that the CBBDQ could be of added value to optimize DMD care.Neurological Motor Disorder

Prevalence of bladder and bowel dysfunction in duchenne muscular dystrophy using the childhood bladder and bowel dysfunction questionnaire

Introduction: Lower urinary tract symptoms (LUTS) and gastrointestinal (GI) problems are common in Duchenne muscular dystrophy (DMD), but not systematically assessed in regular care. We aimed to determine the prevalence of bladder and bowel dysfunction (BBD) in DMD patients compared with healthy controls (HC). Methods: The Childhood Bladder and Bowel Dysfunction Questionnaire (CBBDQ) based on the International Rome III criteria and the International Children’s Continence Society was filled out by 57 DMD patients and 56 HC. Additionally, possible associations of BBD with, for example, medication use or quality of life were evaluated in an additional questionnaire developed by experts. Results: In 74% of patients versus 56% of HC ≥1 LUTS (n.s.) were reported, 68% of patients versus 39% of HC reported ≥1 bowel symptom (p = 0.002) and 53% of patients versus 30% of HC reported combined LUTS and bowel symptoms (p = 0.019). A negative impact of BBD on daily life functioning was reported by 42% of patients. Conclusions: These data underscore that standard screening for BBD is needed and that the CBBDQ could be of added value to optimize DMD care.</p

Common variation in PHACTR1 is associated with susceptibility to cervical artery dissection.

Cervical artery dissection (CeAD), a mural hematoma in a carotid or vertebral artery, is a major cause of ischemic stroke in young adults although relatively uncommon in the general population (incidence of 2.6/100,000 per year). Minor cervical traumas, infection, migraine and hypertension are putative risk factors, and inverse associations with obesity and hypercholesterolemia are described. No confirmed genetic susceptibility factors have been identified using candidate gene approaches. We performed genome-wide association studies (GWAS) in 1,393 CeAD cases and 14,416 controls. The rs9349379[G] allele (PHACTR1) was associated with lower CeAD risk (odds ratio (OR) = 0.75, 95% confidence interval (CI) = 0.69-0.82; P = 4.46 × 10(-10)), with confirmation in independent follow-up samples (659 CeAD cases and 2,648 controls; P = 3.91 × 10(-3); combined P = 1.00 × 10(-11)). The rs9349379[G] allele was previously shown to be associated with lower risk of migraine and increased risk of myocardial infarction. Deciphering the mechanisms underlying this pleiotropy might provide important information on the biological underpinnings of these disabling conditions