Prevalence of Stroke and Vascular Risk Factors among First-Degree Relatives of Stroke Patients and Control Subjects

Gene panel for Mendelian strokes

BACKGROUND

Mendelian stroke causes nearly 7% of ischaemic strokes and is also an important aetiology of cryptogenic stroke. Identifying the genetic abnormalities in Mendelian strokes is important as it would facilitate therapeutic management and genetic counselling. Next-generation sequencing makes large-scale sequencing and genetic testing possible.

METHODS

A systematic literature search was conducted to identify causal genes of Mendelian strokes, which were used to construct a hybridization-based gene capture panel. Genetic variants for target genes were detected using Illumina HiSeq X10 and the Novaseq platform. The sensitivity and specificity were evaluated by comparing the results with Sanger sequencing.

RESULTS

53 suspected patients of Mendelian strokes were analysed using the panel of 181 causal genes. According to the American College of Medical Genetics and Genomics standard, 16 likely pathogenic/variants of uncertain significance genetic variants were identified. Diagnostic testing was conducted by comparing the consistency between the results of panel and Sanger sequencing. Both the sensitivity and specificity were 100% for the panel.

CONCLUSION

This panel provides an economical, time-saving and labour-saving method to detect causal mutations of Mendelian strokes.

Identification of novel biomarkers in ischemic stroke: a genome-wide integrated analysis

BACKGROUND

Ischemic Stroke (IS) is the most common neurological emergency disease and has become the second most frequent cause of death after coronary artery disease in 2015. Owing to its high fatality rate and narrow therapeutic time window, early identification and prevention of potential stroke is becoming increasingly important.

METHODS

We used meta-analysis and bioinformatics mining to explore disease-related pathways and regulatory networks after combining messengerRNA (mRNA) and miRNA expression analyses. The purpose of our study was to screen for candidate target genes and microRNA(miRNA) for early diagnosis of potential stroke.

RESULTS

Five datasets were collected from the Gene Expression Omnibus (GEO) database by systematical retrieval, which contained three mRNA datasets (102 peripheral blood samples in total) and two miRNA dataset (59 peripheral blood samples). Approximately 221 different expression(DE) mRNAs (155 upregulated and 66 downregulated mRNAs) and 185 DE miRNAs were obtained using the metaDE package and GEO2R tools. Further functional enrichments of DE-mRNA, DE-miRNA and protein-protein interaction (PPI) were performed and visualized using Cytoscape.

CONCLUSION

Our study identified six core mRNAs and two regulated miRNAs in the pathogenesis of stroke, and we elaborated the intrinsic role of systemic lupus erythematosus (SLE) and atypical infections in stroke, which may aid in the development of precision medicine for treating ischemic stroke. However, the role of these novel biomarkers and the underlying molecular mechanisms in IS require further fundamental experiments and further clinical evidence.

Whole-Exome Sequencing in 22 Young Ischemic Stroke Patients With Familial Clustering of Stroke

Backgrounds and Purpose- Although new methods for genetic analyses are rapidly evolving, there are currently knowledge gaps in how to detect Mendelian forms of stroke. Methods- We performed whole-exome sequencing in 22 probands, under 56 years at their first ischemic stroke episode, from multi-incident stroke families. With the use of a comprehensive stroke-gene panel, we searched for variants in stroke-related genes. The probands' clinical stroke subtype was related to clinical characteristics previously associated with pathogenic variants in these genes. Relatives were genotyped in 7 families to evaluate stroke-gene variants of unknown significance. In 2 larger families with embolic stroke of unknown source, whole-exome sequencing was performed in additional members to examine the possibility of identifying new stroke genes. Results- Six of 22 probands carried pathogenic or possibly pathogenic variants in genes reported to be associated with their stroke subtype. A known pathogenic variant in NOTCH3 and a possibly pathogenic variant in ACAD9 gene were identified. A novel JAK2:c.3188G>A (p.Arg1063His) mutation was seen in a proband with embolic stroke of undetermined source and prothrombotic status. However, penetrance in the family was incomplete. COL4A2:c.3368A>G (p.Glu1123Gly) was detected in 2 probands but did not cosegregate with the disease in their families. Whole-exome sequencing in multiple members of 2 pedigrees with embolic stroke of undetermined source revealed possibly pathogenic variants in genes not previously associated with stroke, GPR142:c.148C>G (p.Leu50Val), and PTPRN2:c.2416A>G (p.Ile806Val); LRRC1 c.808A>G (p.Ile270Val), SLC7A10c.1294dupG (p.Val432fs), IKBKB: c.1070C>T (p.Ala357Val), and OXGR1 c.392G>A (p.Arg131His), respectively. Conclusions- Screening with whole-exome sequencing using a comprehensive stroke-gene panel may identify rare monogenic forms of stroke, but careful evaluation of clinical characteristics and potential pathogenicity of novel variants remain important. In our study, the majority of individuals with familial aggregation of stroke lacked any identified genetic causes.

Different Types of Family History of Stroke and Stroke Risk: Results Based on 655,552 Individuals

BACKGROUND

Many studies concentrated on the relationships between different types of family history and stroke, but they have not arrived at an unified conclusion. We conducted a comprehensive systematic review to further evaluate the associations.

METHODS

Different databases were searched for related studies published from 1990 to August 2017. The relative risk was considered as the common measure of association across different studies. Heterogeneity of effects across studies was quantified by I².

RESULTS

Sixteen published studies (total participants: 655,552) were eligible in this study. The pooled multifactorial adjusted relative risk (RR) (95% confidence interval [CI]) was 1.40 (1.18, 1.67) for individuals with paternal history, 1.36 (1.20, 1.53) for those with maternal history, and 1.44 (1.17, 1.77) for those with sibling history. Based on cohort studies, the pooled adjusted RRs (95%CIs) for paternal, maternal, and sibling history were 1.33 (1.11-1.59), 1.28 (1.14-1.45), and 1.24 (1.01-1.51), respectively, all of which were smaller than those based on case-control and cross-sectional studies. In studies with large sample size, the respective adjusted RR (95%CI) of stroke for paternal, maternal, and sibling history was 1.30 (1.09, 1.56), 1.30 (1.18, 1.44), and 1.26 (1.02, 1.56), which was lower than that in studies with small sample size.

CONCLUSIONS

Each type of family history of stroke was associated with an increased stroke risk. We could not find significant differences among stroke risks relating to different types of family history of stroke. Thus, paternal, maternal, and sibling history require our equal attention in the stroke prevention and control work.

A stroke gene panel for whole-exome sequencing

Extensive analyses of known monogenic causes of stroke by whole-exome/genome sequencing are technically possible today. We here aimed to compile a comprehensive panel of genes associated with monogenic causes of stroke for use in clinical and research situations. We systematically searched the publically available database Online Mendelian Inheritance in Man, and validated the entries against original peer-reviewed publications in PubMed. First, we selected known pathogenic or putatively pathogenic stroke genes reported in at least one person with stroke, and classified the stroke phenotype for each gene into eight subgroups: (1) large artery atherosclerotic, (2) large artery non-atherosclerotic (tortuosity, dolichoectasia, aneurysm, non-atherosclerotic dissection, occlusion), (3) cerebral small-vessel diseases, (4) cardioembolic (arrhythmia, heart defect, cardiomyopathy), (5) coagulation dysfunctions (venous thrombosis, arterial thrombosis, bleeding tendency), (6) intracerebral hemorrhage, (7) vascular malformations (cavernoma, arteriovenous malformations), and (8) metabolism disorders. Second, we selected other genes that may plausibly cause stroke through diseases related to stroke, but without any documented stroke patient description. A third section comprised SNPs associated with stroke in genome-wide association studies (GWAS). We identified in total 214 genes: 120 associated with stroke, 62 associated with diseases that may cause stroke, and 32 stroke-related genes from recent GWAS. We describe these 214 genes and the clinical stroke subtype(s) associated with each of them. The resulting gene panel can be used to interpret exome sequencing results regarding monogenic stroke. Based on the panel's clinical phenotype description, the pathogenicity of novel variants in these genes may be evaluated in specific situations.

Knowledge and practices related to stroke prevention among hypertensive and diabetic patients attending Specialist Hospital, Sokoto, Nigeria

INTRODUCTION

Stroke has become a problem of public health importance worldwide. Knowledge and practices related to stroke prevention among hypertensive and diabetic patients are important in the control of the disease. In Nigeria, recent reports indicate an emerging epidemic of stroke. This study aimed to determine the knowledge and practices related to stroke prevention among hypertensive and diabetic patients in Sokoto, Nigeria.

METHODS

This was a cross-sectional study among 248 patients attending hypertension and diabetes clinic of Specialist Hospital, Sokoto, Nigeria, selected by systematic sampling technique. A semi-structured questionnaire was used to collect data on the research variables. Data were analyzed using IBM SPSS version 20 statistical package.

RESULTS

The mean age of respondents was 48.21 ± 15.07 years and they were predominantly females (65.7%). The respondents had good knowledge of stroke (70.3%), organs or parts of body affected by stroke (89.1%), signs or symptoms of stroke (87.0%), stroke risk factors (86.6%) and stroke prevention (90.8%). Formal education was the sole predictor of good knowledge of signs or symptoms of stroke (aOR = 3.99, 95% CI = 1.58-10.13, p = 0.004), stroke risk factors (aOR = 4.24, 95% CI = 1.68-10.67, p = 0.002) and stroke prevention (aOR = 3.45, 95% CI = 1.09-10.93, p = 0.035). Stroke prevention practices were sub-optimal and significantly associated with formal education and being employed.

CONCLUSION

These findings suggest the need for all stakeholders to focus on both patients' education and empowerment in halting the rising burden of stroke across the globe.

Familial aggregation of stroke amongst young patients in Lund Stroke Register

BACKGROUND AND PURPOSE

The known monogenic forms of stroke are rare. The aim of this study was to analyze pedigrees of young stroke patients regarding possible monogenic cerebrovascular disease and to evaluate the possibility of genetic stroke in these families. This may contribute to a better understanding of disease mechanism in stroke.

METHODS

Lund Stroke Register includes consecutive patients with first-ever stroke from a defined geographical area in southern Sweden. Early-onset (≤55 years) stroke patients were systematically screened with regard to family history (FHx), and families with stroke aggregation were compiled. Participants provided information in a questionnaire on occurrence of stroke or transient ischaemic attack (TIA) in their families. Information on cardiovascular risk factors (VRFs) and clinical stroke subtype was collected. FHx for stroke was considered positive when the patient reported either ≥1 first-degree relative with stroke/TIA, or no first-degree relative but ≥3 second- or third-degree relatives with stroke/TIA in a distribution compatible with monogenic inheritance.

RESULTS

Of 4103 stroke patients registered, 426 (10%) had first-ever stroke at ≤55 years and 338 (79%) of these answered the questionnaire. Of them, 159 (47%) reported a positive FHx. Twenty-eight (18%) of the probands with positive FHx had no known VRFs. Thirty-two families with ≥4 members with stroke were identified. In all these larger families the affected individuals with stroke were present in more than one generation.

CONCLUSION

Aggregation of stroke in families of early-onset stroke patients is not uncommon. Genetic factors with impact on stroke risk, including monogenic causes, need to be evaluated in future stroke studies.

Stroke genetics: a review and update

Stroke genetics includes several topics of clinical interest, including (1) molecular genetic variations affecting risk of monogenic stroke syndromes; (2) molecular genetic variations affecting risk of common stroke syndromes, sometimes with specific effects on risk of specific main types of stroke or subtypes of ischemic and hemorrhagic stroke; (3) genetics of conditions associated with stroke risk e.g. white matter hyperintensities, atrial fibrillation and hypertension; (4) hereditary causes of familial aggregation of stroke; (5) epigenetic impact on protein expression during acute brain injury; (6) genetic influence on stroke recovery; and (7) pharmacogenetics. Genetic research methods include candidate gene studies; Genome Wide Association Studies; family studies; RNA and protein analyses; and advanced computer-aided analytical methods to detect statistically significant associations. Several methods that could improve our knowledge of stroke genetics are being developed e.g.: Exome content analysis; Next-generation sequencing; Whole genome sequencing; and Epigenetics. During 2012-2014, several Single Nucleotide Polymorphisms (SNPs) have been related to common ischemic stroke risk. Certain SNPs have been associated with risk of specific ischemic stroke subtypes such as large vessel disease and cardiac embolism, particular subtypes of intracerebral hemorrhage (ICH), especially lobar ICH, and with prognosis after ICH. Large international studies on stroke recovery and exome content are ongoing. Advanced mathematical models have been used to study how several SNPs can act together and increase stroke risk burden. Such efforts require large numbers of patients and controls, which is achieved by co-operation in large international consortia such as the International Stroke Genetics Consortium. This overview includes an introduction to genetics, stroke genetics in general, and different genetic variations that may influence stroke risk. It presents some of the latest reports on stroke genetics published in high impact journals. The role of pharmacogenetics, the current clinical situation, and future prospects will also be discussed.

Documentation of atrial fibrillation prior to first-ever ischemic stroke

OBJECTIVES

We assessed the prevalence of atrial fibrillation (AF) prior to first-ever ischemic stroke by examining a comprehensive electronic ECG archive.

METHODS

The study sample comprised 336 consecutive stroke patients (median age 76 (IQ16) y, 200 men) enrolled in Lund Stroke Register from March 2001 to February 2002 and 336 age- and gender-matched controls without stroke history. AF prior to admission was studied using the regional electronic ECG database and record linkage with the National Swedish Hospital Discharge Register (SHDR). Medical records were reviewed for AF documentation and CHA2 DS2-VASc risk score.

RESULTS

Atrial fibrillation before or at stroke onset was detected in 109 (32.4%) stroke patients and 44 (13.1%) controls, P<0.001. Twenty-five of 109 stroke patients had AF detected only on previous ECG (n=14) or through the SHDR (n=11). The most prevalent type of AF in stroke group was non-permanent AF (59.6%). AF prevalence among patients admitted with sinus rhythm at hospital admission (n=266) was higher in those with CHA2 DS2 -VASc score≥6 (28.6%) than with CHA2 DS2-VASc score<6 (13.0%), P=0.043.

CONCLUSION

Comprehensive approach for AF screening allows detecting AF in one-third of patients admitted with first-ever ischemic stroke. Patients with high cardiovascular risk are more likely to have non-permanent AF.

Effect of an intervention to improve the cardiovascular health of family members of patients with coronary artery disease: a randomized trial

BACKGROUND

Family members of patients with coronary artery disease (CAD) have higher risk of vascular events. We conducted a trial to determine if a family heart-health intervention could reduce their risk of CAD.

METHODS

We assessed coronary risk factors and randomized 426 family members of patients with CAD to a family heart-health intervention (n = 211) or control (n = 215). The intervention included feedback about risk factors, assistance with goal setting and counselling from health educators for 12 months. Reports were sent to the primary care physicians of patients whose lipid levels and blood pressure exceeded threshold values. All participants received printed materials about smoking cessation, healthy eating, weight management and physical activity; the control group received only these materials. The main outcomes (ratio of total cholesterol to high-density lipoprotein [HDL] cholesterol; physical activity; fruit and vegetable consumption) were assessed at 3 and 12 months. We examined group and time effects using mixed models analyses with the baseline values as covariates. The secondary outcomes were plasma lipid levels (total cholesterol, low-density lipoprotein cholesterol, HDL cholesterol and triglycerides); glucose level; blood pressure; smoking status; waist circumference; body mass index; and the use of blood pressure, lipid-lowering and smoking cessation medications.

RESULTS

We found no effect of the intervention on the ratio of total cholesterol to HDL cholesterol. However, participants in the intervention group reported consuming more fruit and vegetables (1.2 servings per day more after 3 mo and 0.8 servings at 12 mo; p < 0.001). There was a significant group by time interaction for physical activity (p = 0.03). At 3 months, those in the intervention group reported 65.8 more minutes of physical activity per week (95% confidence interval [CI] 47.0-84.7 min). At 12 months, participants in the intervention group reported 23.9 more minutes each week (95% CI 3.9-44.0 min).

INTERPRETATION

A health educator-led heart-health intervention did not improve the ratio of total cholesterol to HDL cholesterol but did increase reported physical activity and fruit and vegetable consumption among family members of patients with CAD. Hospitalization of a spouse, sibling or parent is an opportunity to improve cardiovascular health among other family members.

TRIAL REGISTRATION

clinicaltrials.gov, no NCT00552591.

The relationship of a family history for hypertension, myocardial infarction, or stroke with cardiovascular physiology in young women

Cardiovascular disease (CVD) and preeclampsia share several pathophysiologic risk factors. We examined family history (FH) and physiologic status in 60 healthy, nulliparous women to determine the relationship between FH and known risk factors for CVD. Data are presented as mean ± standard error (SE). Decreased uterine blood flow was observed in women with FH of hypertension (+FH: 21.5 ± 1.7, no FH: 33.3 ± 9.0 mL/min; P = .04). Women reporting an FH of stroke showed increased alpha- and beta-adrenergic response, as measured by Valsalva maneuver (α: FH: 24.7 ± 1.9, -FH: 18.9 ± 1.1 mm Hg, P = .02; β: FH: 22.0 ± 2.1, -FH: 16.9 ± 1.4 mm Hg; P = .04), and increased cardiac output (4.83 ± 0.22 vs 4.31 ± 0.12 L/min; P = .01). We identified no significant physiologic associations linked to an FH of myocardial infarction. Our observations show significant differences in physiologic characteristics in women with specific CVD family histories. These data, coupled with known heritable contributions to CVD and preeclampsia, suggest a distinct physiologic phenotype that may link preeclampsia risk with FH of CVD, independent of pregnancy.

Estimating the magnitude of genetic factors by calculating the genetic relative risk of stroke in first-ever lacunar stroke patients

BACKGROUND

Positive family history of stroke is an independent risk factor for lacunar stroke. However, the magnitude of familial aggregation of a certain disease is better evaluated by the genetic relative risk. This is calculated by dividing the prevalence of specific disease in family members of patients by the prevalence of this disease in the general population. In a cohort of lacunar stroke patients, who were subtyped clinically and radiologically, we determined the genetic relative risk of stroke.

METHODS

By questionnaire and additional interview, we obtained a complete first-degree family history of stroke. The prevalence of stroke in first-degree relatives of these lacunar stroke patients was compared to the self-reported prevalence of stroke in a Dutch community based cohort of elderly volunteers. Secondly, the influence of proband characteristics and family composition on parental and sibling history of stroke were evaluated.

PRINCIPAL FINDINGS

We collected data of 1066 first-degree relatives of 195 lacunar stroke patients. Strokes occurred in 13.5% of first-degree relatives. The genetic relative risk was 2.94 (95%CI 2.45-3.53) for overall first-degree relatives, 4.52 (95%CI 3.61-5.65) for patients' parents and 2.10 (95%CI 1.63-2.69) for patients' siblings. Age of proband and proband status for hypertension influenced the chance of having a parent with a history of stroke whereas the likelihood of having a concordant sibling increased with sibship size.

CONCLUSIONS

We found an increased genetic relative risk of stroke in first-degree relatives of patients with lacunar stroke. Our data warrant further genomic research in this well-defined high risk population for stroke.

Family history of stroke is an independent risk factor for lacunar stroke subtype with asymptomatic lacunar infarcts at younger ages

BACKGROUND AND PURPOSE

Results from case-control and case-case studies indicate that a positive family history of stroke (FHstroke) is an independent risk factor for lacunar stroke. Different lacunar stroke phenotypes can be distinguished on the basis of the presence of asymptomatic lacunar infarcts (aLACs), ischemic white-matter lesions, or brain microbleeds. The aim of the present study was to determine whether familial aggregation of stroke was different for lacunar stroke phenotypes.

METHODS

In 157 patients with a first-ever lacunar stroke, a complete first-degree FHstroke was obtained by a standardized questionnaire and additional interview. Lacunar stroke patients were categorized successively into groups, depending on the presence of aLACs, ischemic white-matter lesions, and brain microbleeds on magnetic resonance imaging.

RESULTS

Fifty-two percent of patients reported a positive FHstroke in at least one of their first-degree relatives. In younger (<65 years) probands, a high frequency of parental FHstroke (59% versus 20%, P<0.01) in those with aLACs compared with probands without aLACs was found. In multivariate analysis, the strongest associations were found for parental FHstroke (odds ratio=6.46; 95% CI=1.96 to 21.33), maternal FHstroke (odds ratio=4.00; 95% CI=1.18 to 13.56), and paternal FHstroke (odds ratio=5.40; 95% CI=1.14 to 25.61).

CONCLUSIONS

A family history of stroke might be an independent risk factor for the lacunar stroke phenotype with aLACs at younger ages, suggesting a role for genetic factors in this phenotype caused by diffuse vasculopathy.

The stroke offspring study: is parental stroke history of value in targeted risk factor screening?

AIM

This study aimed to compare the prevalence of stroke risk factors among people with a parental history of stroke to those in a control group of individuals, of similar age, gender and social class, with no parental stroke history.

BACKGROUND

Parental stroke increases an individual's risk of stroke, but little is known of the potential value of using this information in targeted screening for primary prevention in general practice.

METHOD

We sent questionnaires to 300 randomly selected individuals aged 40-65 years, in each of 11 different general practices in Northern Ireland. Among 1061 responses received within six weeks, 332 reported a parental history of stroke (31.3%). We matched respondents with (cases) and without (controls) a parental history of stroke on characteristics of age, gender and socioeconomic status. Matched pairs were invited to attend a consultation at which their diet and exercise habits were assessed using validated questionnaires and height, weight, blood pressure and serum lipids and glucose were measured.

FINDINGS

Matched data were available for 199 case-control pairs (398 individuals). Mean systolic and diastolic blood pressures were significantly higher in cases than in paired controls (systolic 146.3 versus 140.6 mmHg (P < 0.01); diastolic 87.7 versus 85.0 mmHg (P = 0.014)). Cases consumed more alcohol than their paired controls (13.8 versus 10.1 U/week (P < 0.01)), but their measures of body mass index, lipids, diabetes, diet and exercise did not differ significantly. The results of this study suggest that screening offspring of patients with stroke in respect of blood pressure has potential value in identifying people likely to benefit from primary prevention, but do not support the adoption of a targeted screening strategy for other commonly cited stroke risk factors.

Genetic variant on chromosome 12p13 does not show association to ischemic stroke in 3 Swedish case-control studies

BACKGROUND AND PURPOSE

in a genome-wide association study and subsequent case-control studies, the single-nucleotide polymorphism rs12425791 on chromosome 12p13 was reported to be associated with ischemic stroke, but this could not be validated in a recent well-powered study. We therefore investigated whether an association between ischemic stroke and rs12425791 could be detected in 3 different case-control studies from the southwest of Sweden.

METHODS

we examined 3606 patients with ischemic stroke and 2528 controls from 3 independent case-controls studies.

RESULTS

no significant association between ischemic stroke and the single-nucleotide polymorphism rs12425791 was detected in any of the 3 case-control samples or in the samples combined. The odds ratio for ischemic stroke for the minor allele in the combined sample was 1.02 (95% CI, 0.93 to 1.13).

CONCLUSIONS

the single-nucleotide polymorphism rs12425791 does not confer a substantial risk for ischemic stroke in our population. Our results support a recent large study including other European populations.

Parental occurrence of stroke and risk of stroke in their children: the Framingham study

BACKGROUND

Data relating parental history of stroke to stroke risk in offspring remain surprisingly inconsistent, largely because of heterogeneity of study design and the absence of verified, as opposed to historical, data on parental stroke status.

METHODS AND RESULTS

We determined whether prospectively verified parental occurrence of stroke increased incident stroke risk among offspring in a community-based sample by studying 3443 stroke-free Framingham offspring (53% female; mean age, 48+/-14 years) with verified parental stroke status (by 65 years of age) who attended the first, third, fifth, and/or seventh offspring examinations and were followed up for up to 8 years after each baseline examination. Over up to 11,029 such person-observation periods (77,534 person-years), we documented 106 parental strokes by 65 years of age and 128 offspring strokes (74 parental and 106 offspring strokes were ischemic). Using multivariable Cox models adjusted for age, sex, sibship, and baseline stroke risk factors, we observed that parental stroke, both all stroke generally and ischemic stroke specifically, was associated with an increased risk of incident stroke of the same type in the offspring (hazard ratio, 2.79; 95% confidence interval, 1.68 to 4.66; P<0.001 for all stroke; and hazard ratio, 3.15; 95% confidence interval, 1.69 to 5.88; P<0.001 for ischemic stroke). This was true for both maternal and paternal stroke.

CONCLUSIONS

Documented parental stroke by 65 years of age was associated with a 3-fold increase in risk of offspring stroke. This increased risk persisted after adjustment for conventional stroke risk factors. Thus, verified parental stroke may serve as a clinically useful risk marker of an individual's propensity to stroke.

Sex Differences in Heritability of Ischemic Stroke

Background and Purpose— Using data from Oxfordshire, UK, we recently showed that women are more likely than men to have a family history of stroke in female versus male first degree relatives. To test the generalizability of this finding, we did a comprehensive systematic review of all available published and unpublished data.

Methods— Studies were included in the present review if they reported the frequency of family history of stroke in relation to sex of parent or proband. Where necessary, we contacted authors of studies to obtain unpublished data. Data from the Oxford Vascular Study (OXVASC) and 3 other Oxford cohorts (1925 patients) were secondarily pooled with the data from other studies.

Results— We obtained data from 18 studies (7941 patients), including unpublished data from 7 studies. Female probands were slightly more likely to have a parental history of stroke than male probands (pooled OR=1.15; 95% CI: 1.03 to 1.29; P (sig) =0.028; P (het) =0.45). Maternal history of stroke was more common than paternal history (pooled OR=1.25; 1.15 to 1.37; P (sig) <0.00001; P (het) =0.12). However, the maternal excess was only present in female probands (pooled OR=1.47; 1.27 to 1.70; P (sig) <0.00001; P (het) =0.11). In contrast, male probands were no more likely to have maternal than paternal history of stroke (pooled OR=1.02; 0.88 to 1.17, P (sig) =0.43; P (het) =0.09).

Conclusions— Women with stroke are more likely than men to have a parental history of stroke, which is accounted for by an excess maternal history of stroke. This finding could be explained by sex-specific genetic, epigenetic, or nongenetic mechanisms.

Polymorphism of apolipoprotein E (APOE) and lipoprotein lipase (LPL) genes and ischaemic stroke in individuals of Yakut ethnicity

There is evidence that most forms of ischaemic stroke (IS) result from synergistic effects of the modifiable predisposing factors and multiple genes. In the present work, we report results of case-control study of IS association with apolipoprotein E gene (APOE) (promoter and coding polymorphisms) and lipoprotein lipase gene (LPL) (presence/absence of a HindIII cutting site). We studied 107 unrelated patients of Yakut ethnicity (69 men and 38 women, mean age 58.4+/-11.5 years) with first-ever IS in carotid/middle cerebral artery regions. The control group included 101 subjects of the same ethnicity (61 men and 40 women, mean age 57.6+/-11.6 years) free of clinically detectable cerebrovascular disease, and without any history of stroke. A positive association of IS with APOE -427T allele (p=0.0012, OR=3.99) and -427T/T genotype (p=0.0005, OR=4.96) and a negative association with -427C allele (p=0.0012, OR=0.25), -427T/C genotype (p=0.0003, OR=0.18), epsilon2 allele (p=0.018, OR=0.35), epsilon2/3 genotype (p=0.017, OR=0.28) and -491A/-427C/epsilon2 haplotype (p=0.0026, OR=0.18) were observed. For atherothrombotic subgroup the same allele and genotype associations were found plus association with APOE -491A allele (p=0.026, OR=3.98). No reliable IS associations were found with LPL T+495G (HindIII) polymorphism. An association of APOE promoter polymorphisms (A-491T, T-427C) with an IS is shown in our study for the first time. Our study provides evidence for the role of APOE gene as a prognostic genetic marker for IS, especially for its atherothrombotic subtype.