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Background and Purpose- Although exogenous hormone therapy (HT) use has been associated with increased risk of ischemic stroke in postmenopausal women, it remains unknown whether sex hormone levels contribute to ischemic stroke risk. We aimed to estimate associations between plasma sex hormone levels and ischemic stroke risk, by HT status, in a nested case-control study of postmenopausal women from the NHS (Nurses' Health Study). Methods- Women with confirmed incident ischemic stroke (n=419) were matched with controls (n=419) by age, HT use, and other factors. Plasma estradiol and testosterone levels were measured using liquid chromatography tandem mass spectrometry; SHBG (sex hormone-binding globulin) was assayed by electrochemiluminescence immunoassay. Associations of total and free estradiol and testosterone, the estradiol/testosterone ratio, and SHBG with ischemic stroke were estimated using conditional logistic regressions stratified by HT status with adjustment for matching and cardiovascular risk factors. Results- Current HT users had different hormone profiles from never/past users. No clear linear trends were observed between estradiol (total or free) levels or the estradiol/testosterone ratio and ischemic stroke risk among either current users ( P trend >0.6). For both current and never/past users, the associations between some of the sex hormones and ischemic stroke differed by body mass index categories ( P trend , a higher estradiol/testosterone ratio was associated with significantly elevated ischemic stroke risk among current users ( P =0.01), and higher levels of total and free estradiol were significantly associated with higher ischemic stroke risk among never/past users ( interaction ≤0.04). Testosterone and SHBG were not associated with ischemic stroke in either current or never/past users. Conclusions- Our findings do not support a role of sex hormone levels in mediating ischemic stroke risk among postmenopausal women. Replications in additional larger studies are required.2 , a higher estradiol/testosterone ratio was associated with significantly elevated ischemic stroke risk among current users ( P trend =0.01), and higher levels of total and free estradiol were significantly associated with higher ischemic stroke risk among never/past users ( P trend ≤0.04). Testosterone and SHBG were not associated with ischemic stroke in either current or never/past users. Conclusions- Our findings do not support a role of sex hormone levels in mediating ischemic stroke risk among postmenopausal women. Replications in additional larger studies are required.

Background and Purpose- In the United States, black Americans exhibit a greater risk of stroke and burden of stroke risk factors than whites; however, it is unclear whether these stroke risk factors influence stroke risk differently across racial groups. Methods- In total, 126 018 participants of the Women's Health Initiative (11 389 black and 114 629 white women), free of stroke and coronary heart disease at baseline (1994-1998), were followed through 2010. Participants completed baseline clinical exams with standardized measurements of blood pressure and anthropometrics, medication inventory and self-reported questionnaires on sociodemographics, behaviors/lifestyle, and medical history. Incident total, ischemic and hemorrhagic strokes were updated annually through questionnaires with medical record confirmation. Rate differences (per 100 000 person-years) and hazard ratios (HR) based on multivariable Cox models and were estimated. Results- Over a median of 13 years, 4344 stroke events were observed. Absolute incidence rates were higher in black than white women in each age group. In age-adjusted analyses, the risk of stroke was significantly higher among black compared with white women (HR=1.47, 95% CI, 1.33-1.63); adjustment for stroke risk factors, which may be on the causal pathway, attenuated the estimate. Racial disparities were greatest among women 50 to <60 years (HR=3.48; 95% CI, 2.31-5.26; rate difference =99) and diminished with increasing age (60 to <70 HR=1.80; 95% CI, 1.50-2.16; rate difference =107; ≥70 years: HR=1.26; 95% CI, 1.10-1.43; rate difference =87; P interaction <0.001). Black women 50 to <60 years remained at significantly higher risk than white women after adjustment for stroke risk factors (HR=1.76; 95% CI, 1.09-2.83). Conclusions- There was a moderately greater risk of total stroke among black compared with white women; however, racial disparities were greatest among women aged 50 to <60 years. Interventions targeted at younger black women may provide the greatest benefit in reducing disparities.

Biologic sex influences many variables that are important to brain health in general, and to stroke or cerebral ischemia in particular, such as general health status, cerebrovascular anatomy and function, unique risk factors such as pregnancy and preeclampsia, symptomatology, and therapeutic response. A more complete understanding of the scale and depth of sexual dimorphism in the brain and the role of more general sex-based factors is crucial to reducing the burden of stroke in women and men. This focused review highlights recent findings in stroke, including sex differences in epidemiology, risk factor reduction, comparative use of stroke therapeutics in both sexes, the importance of frailty in women, and the biologic basis for sex differences in stroke. Such findings show tremendous promise for the future of personalized medicine in stroke prevention and treatment.

Competing Interests: The American Heart Association makes every effort to avoid any actual or potential conflicts of interest that may arise as a result of an outside relationship or a personal, professional, or business interest of a member of the writing panel. Specifically, all members of the writing group are required to complete and submit a Disclosure Questionnaire showing all such relationships that might be perceived as real or potential conflicts of interest.

Background: Plasma retinol-binding protein 4 (RBP4) levels have been associated with cardiovascular risk factors and risk of coronary heart disease, but little is known about the association between RBP4 and the risk of ischemic stroke. We hypothesized that elevated RBP4 levels would be associated with an increased risk of ischemic stroke among women., Methods: We performed a nested case-control study among women enrolled in the Nurses' Health Study who provided blood samples between 1989 and 1990 and were free of prior stroke and cancer. We measured prediagnostic RBP4 levels in 471 ischemic stroke cases who were confirmed by medical record review and in 471 controls who were matched 1:1 to the cases on age, race, blood collection date, menopausal status, postmenopausal hormone use, and smoking status. We analyzed the association between RBP4 levels and ischemic stroke using multivariable conditional logistic regression conditional on the matching factors and adjusted for physical activity, body mass index, aspirin use, alcohol consumption, diet, history of diabetes, high cholesterol, high blood pressure, or heart disease, and cholesterol and hemoglobin A1C levels., Results: Median levels of RBP4 were similar in cases (31.1 µg/mL) and controls (31.0 µg/mL; P value from the Wilcoxon rank-sum test = .82). Quartiles of RBP4 were not associated with an increased risk of ischemic stroke (highest quartile compared to lowest quartile: multivariate-adjusted odds ratio, .75; 95% confidence interval, .48, 1.17). We also did not observe associations between RBP4 and ischemic stroke of thrombotic or embolic origin., Conclusions: Elevated levels of RBP4 were not associated with an increased risk of ischemic stroke., (Copyright © 2018 National Stroke Association. Published by Elsevier Inc. All rights reserved.)

Objective: To determine whether elevated β 2 -microglobulin (B2M) levels were associated with an increased risk of incident ischemic stroke events among women., Methods: We performed a nested case-control study among women enrolled in the Nurses' Health Study who provided blood samples between 1989 and 1990 and were free of prior stroke and cancer. We measured B2M levels in 473 ischemic strokes cases confirmed by medical record review and in 473 controls matched 1:1 to the cases on age, race, date of blood collection, menopausal status, postmenopausal hormone use, and smoking status. We analyzed the association between B2M and ischemic stroke using multivariable conditional logistic regression to adjust for traditional stroke risk factors., Results: Median levels of B2M were higher among cases (1.86 mg/L) than controls (1.80 mg/L, p = 0.009, Wilcoxon rank-sum test). Women in the highest B2M quartile had a multivariable-adjusted increased risk of ischemic stroke compared to those in the lowest quartile (odds ratio [OR] 1.56, 95% confidence interval [CI] 1.02-2.39). Results were similar when restricted to those without evidence of chronic kidney disease (estimated glomerular filtration rate ≥60 mL·min -1 ·1.73 m -2 ) (OR 1.49, 95% CI 1.08-2.06). In an exploratory analysis, the association between B2M and thrombotic stroke was similar to the overall ischemic stroke results, but no association was observed for embolic stroke risk., Conclusion: High levels of B2M were associated with an increased risk of ischemic stroke among women., (© 2017 American Academy of Neurology.)

Background: Markers of systemic inflammation (high-sensitivity C-reactive protein [hsCRP], soluble intercellular adhesion molecule 1 [sICAM-1], and fibrinogen) have been associated with a greater risk of total and ischemic stroke, in addition to elevated blood pressure. However, the role of these inflammatory markers on stroke pathophysiology by hypertension status is uncertain., Methods: Blood samples were collected and assayed for hsCRP, sICAM-1, and fibrinogen among 27,330 initially healthy women from the Women's Health Study, and women were followed up from 1992 to 2013. Prior to randomization, the baseline questionnaire collected self-reported hypertension status, cardiovascular risk factors, and lifestyle factors. New cases of total, ischemic, and hemorrhagic stroke were updated annually through questionnaires and confirmed by medical records according to the National Survey of Stroke criteria. Multivariable Cox models estimated overall associations between each inflammatory marker and stroke and separately stratified by hypertension status., Results: We observed 629 incident total strokes over 477,278 person-years. In adjusted analyses, extreme quartiles of hsCRP and sICAM-1 were each associated with a significantly greater risk of total stroke (hsCRP: hazard ratios [HR] = 1.77, 95% confidence interval [CI]: 1.39-2.26; sICAM-1: HR = 1.28, 95% CI: 1.00-1.63). Fibrinogen was not associated with a significantly greater stroke risk. In analyses stratified by hypertension status, elevated hsCRP was associated with a nonstatistically significant greater risk of total stroke among prehypertensive and hypertensive women., Conclusions: These data indicate that hsCRP and sICAM-1 are associated with hypertension status and stroke risk among women. Further work should examine the role of inflammatory markers on ischemic stroke subtypes and clarify mechanisms., (© American Journal of Hypertension, Ltd 2016. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Background: High-sensitivity C-reactive protein (hsCRP), a marker of systemic inflammation, may promote atherosclerosis, particularly among adults with elevated blood pressure; however, data are sparse. We examined the association between hsCRP concentrations and risk of total stroke by hypertension status (normotension, prehypertension, and hypertension) among men in the Physicians' Health Study (PHS)., Methods and Results: Blood samples were collected (1996-1997) and assayed for hsCRP among 10 456 initially healthy men from PHS I and PHS II and followed from 1997 to 2012. Self-reported hypertension status, cardiovascular risk factors, lifestyle, and alcohol consumption were obtained from the baseline questionnaire prior to randomization in PHS II. Strokes were updated approximately annually and confirmed by medical records according to the National Survey of Stroke criteria. Multivariable Cox models were used. We observed 395 incident total strokes over 115 791 person-years. In analyses adjusted for potential confounders and stroke risk factors, clinically elevated hsCRP (>3 mg/L) was associated with a 40% significantly greater hazard of total stroke compared with hsCRP <1 mg/L (hazard ratio 1.40, 95% CI 1.06 to 1.87; Ptrend=0.01). Additional adjustment for blood pressure and biomarkers associated with cardiovascular risk marginally attenuated the estimates. Results were similar by hypertension status, although not statistically significant among normotensive and prehypertensive participants due to limited events., Conclusions: Elevated hsCRP levels were associated with a greater risk of total stroke, even after adjustment for potential confounders and cardiovascular risk factors. Risk of total stroke was significantly higher among hypertensive men with elevated hsCRP compared with normotensive men with low hsCRP., (© 2015 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.)

Background and Purpose: Lower plasma magnesium levels may be associated with higher blood pressure and endothelial dysfunction, but sparse prospective data are available for stroke., Methods: Among 32,826 participants in the Nurses' Health Study who provided blood samples in 1989 to 1990, incident ischemic strokes were identified and confirmed by medical records through 2006. We conducted a nested case-control analysis of 459 cases, matched 1:1 to controls on age, race/ethnicity, smoking status, date of blood draw, fasting status, menopausal status, and hormone use. We used conditional logistic regression models to estimate the multivariable adjusted association of plasma magnesium and the risk of ischemic stroke and ischemic stroke subtypes., Results: Median magnesium levels did not differ between ischemic stroke cases and controls (median, 0.86 mmol/L for both; P=0.14). Conditional on matching factors, women in the lowest magnesium quintile had a relative risk of 1.34 (95% confidence interval, 0.86-2.10; P trend=0.13) for total ischemic stroke compared with women in the highest quintile. Additional adjustment for risk factors and confounders did not substantially alter the risk estimates for total ischemic stroke. Women with magnesium levels<0.82 mmol/L had significantly greater risk of total ischemic stroke (multivariable relative risk, 1.57; 95% confidence interval, 1.09-2.27; P=0.01) and thrombotic stroke (multivariable relative risk, 1.66; 95% confidence interval, 1.03-2.65; P=0.03) compared with women with magnesium levels≥0.82 mmol/L. No significant effect modification was observed by age, body mass index, hypertension, or diabetes mellitus., Conclusions: Lower plasma magnesium levels may contribute to higher risk of ischemic stroke among women., (© 2014 American Heart Association, Inc.)

Background: Fetuin-A, a protein secreted primarily by the liver, has been associated with nonalcoholic fatty liver disease and insulin resistance. In a recent study, higher circulating fetuin-A was associated with cardiovascular events, particularly ischemic stroke. However, these data have not been replicated., Methods: A nested case control design was used to examine the relationship between fetuin-A and ischemic stroke among female participants of the Nurses' Health Study. Fetuin-A was measured in blood samples collected and stored between 1989 and 1990. A total of 459 incident cases of ischemic stroke were identified and confirmed by medical records according to the National Survey of Stroke criteria between 1990 and 2006 and matched to 459 controls by age, race/ethnicity, date of sample collection, menopausal status, postmenopausal hormone use, and smoking status. The association between fetuin-A and ischemic stroke was modeled using conditional logistic regression., Results: Circulating fetuin-A was higher in women (P < 0.01) who reported increased body mass index (BMI) of ≥25 kg/m(2), total cholesterol ≥200 mg/dL, high-sensitivity C-reactive protein ≥3 mg/L, and current hormone use at baseline. Significant partial Spearman correlations (P < 0.001), adjusted for matching factors, were found between measured concentrations of fetuin-A and triglycerides (r = 0.20), C-reactive protein (r = 0.14), and BMI (r = 0.15). Fetuin-A quartiles were not significantly associated with increased risk of incident ischemic stroke when adjusted for matching factors (relative risk, 1.03; 95% CI, 0.69-1.54, extreme quartiles); additional adjustment for lifestyle factors or cardiovascular disease risk factors and biomarkers did not alter results., Conclusions: In this sample of women, fetuin-A was not significantly associated with risk of ischemic stroke. Further research is needed to explore this association.

Background and Purpose: Previous research suggests greater risk of coronary heart disease with lower levels of the adrenal steroid dehydroepiandrosterone sulfate (DHEAS). No studies have examined the association between DHEAS and risk of ischemic stroke. DHEAS may influence ischemic stroke risk through atherosclerotic-related mechanisms (endothelial function and smooth muscle cell proliferation) or insulin resistance., Methods: Between 1989 and 1990, 32 826 women without prior stroke in the Nurses' Health Study, an observational cohort, provided blood samples and were followed up for cardiovascular events. Among this sample, using a nested case-control design, 461 ischemic strokes were confirmed by medical records by 2006. Cases were matched to controls free of stroke at the time of the index case and by age, race, menopausal status, postmenopausal hormone use, smoking status, and date of sample collection. Multivariable conditional logistic regression was used., Results: Median DHEAS levels did not differ between cases (median=58.7) and controls (median=66.0; P=0.10). Conditional on matching factors, the lowest DHEAS quartile exhibited a relative risk of 1.30 for ischemic stroke (95% confidence interval, 0.88-1.94), compared with the highest quartile and marginally unchanged when adjusted for confounders (relative risk=1.33; 95% confidence interval, 0.87-2.02). When modeled as a binary variable dichotomized at the lowest quartile, women with low DHEAS (≤the lowest quartile) had a significantly increased multivariable adjusted risk of ischemic stroke compared with those with higher levels (relative risk=1.41; 95% confidence interval, 1.03-1.92)., Conclusions: Lower DHEAS levels were associated with a greater risk of ischemic stroke, even after adjustment for potential confounders. These novel observations warrant confirmation in other populations.

Each year, the American Heart Association (AHA), in conjunction with the Centers for Disease Control and Prevention, the National Institutes of Health, and other government agencies, brings together in a single document the most up-to-date statistics related to heart disease, stroke, and the factors in the AHA's Life's Simple 7 (Figure1), which include core health behaviors (smoking, physical activity [PA], diet, and weight) and health factors (cholesterol, blood pressure [BP], and glucose control) that contribute to cardiovascular health. The Statistical Update represents a critical resource for the lay public, policy makers, media professionals, clinicians, healthcare administrators, researchers, health advocates, and others seeking the best available data on these factors and conditions. Cardiovascular disease (CVD) and stroke produce immense health and economic burdens in the United States and globally. The Update also presents the latest data on a range of major clinical heart and circulatory disease conditions (including stroke, congenital heart disease, rhythm disorders, subclinical atherosclerosis, coronary heart disease, heart failure (HF), valvular disease, venous disease, and peripheral arterial disease) and the associated outcomes (including quality of care, procedures, and economic costs). Since 2006, the annual versions of the Statistical Update have been cited >20 000 times in the literature. In 2015 alone, the various Statistical Updates were cited ≈4000 times. Each annual version of the Statistical Update undergoes revisions to include the newest nationally representative data, add additional relevant published scientific findings, remove older information, add new sections or chapters, and increase the number of ways to access and use the assembled information. This year-long process, which begins as soon as the previous Statistical Update is published, is performed by the AHA Statistics Committee faculty volunteers and staff and government agency partners. This year's edition includes new data on the monitoring and benefits of cardiovascular health in the population, new metrics to assess and monitor healthy diets, a new chapter on venous disease and pulmonary hypertension (PH), new information on stroke in young adults, an enhanced focus on underserved and minority populations, a substantively expanded focus and chapter on the global burden of CVD, and further evidence-based approaches to changing behaviors, implementation strategies, and implications of the AHA's 2020 Impact Goals. Below are a few highlights from this year's Update. [ABSTRACT FROM AUTHOR]