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Stroke is a leading cause of severe, long-term disability. Most stroke survivors are cared for in the home by a family caregiver. Caregiver stress is a leading cause of stroke survivor institutionalization, which results in significant costs to the healthcare system. Stroke family caregiver and dyad intervention studies have reported a variety of outcomes. A critical analysis of 17 caregiver intervention studies and 15 caregiver/stroke survivor dyad intervention studies was conducted to provide evidence-based recommendations for the implementation and future design of stroke family caregiver and dyad interventions., (© 2014 American Heart Association, Inc.)

Background and Purpose: Brain-derived neurotrophic factor (BDNF), a major neurotrophin and vascular endothelial growth factor (VEGF) have a documented role in neurogenesis, angiogenesis, and neuronal survival. In animal experiments, they impact infarct size and functional motor recovery after an ischemic brain lesion. We sought to examine the association of serum BDNF and VEGF with the risk of clinical stroke or subclinical vascular brain injury in a community-based sample., Methods: In 3440 Framingham Study participants (mean age, 65±11 years; 56% women) who were free of stroke/transient ischemic attack (TIA), we related baseline BDNF and logVEGF to risk of incident stroke/TIA. In a subsample with brain MRI and with neuropsychological tests available (n=1863 and 2104, respectively; mean age, 61±9 years, 55% women, in each), we related baseline BDNF and logVEGF to log-white matter hyperintensity volume on brain MRI, and to visuospatial memory and executive function tests., Results: During a median follow-up of 10 years, 193 participants experienced incident stroke/TIA. In multivariable analyses adjusted for age, sex, and traditional stroke risk factors, lower BDNF and higher logVEGF levels were associated with an increased risk of incident stroke/TIA (hazard ratio comparing BDNF Q1 versus Q2-Q4, 1.47; 95% confidence interval, 1.09-2.00; P=0.012 and hazard ratio/SD increase in logVEGF, 1.21; 95% confidence interval, 1.04-1.40; P=0.012). Persons with higher BDNF levels had less log-white matter hyperintensity volume (β±SE=-0.05±0.02; P=0.025), and better visual memory (β±SE=0.18±0.07; P=0.005)., Conclusions: Lower serum BDNF and higher VEGF concentrations were associated with increased risk of incident stroke/TIA. Higher levels of BDNF were also associated with less white matter hyperintensity and better visual memory. Our findings suggest that circulating BDNF and VEGF levels modify risk of clinical and subclinical vascular brain injury.

Background and Purpose: White matter hyperintensities and MRI-defined brain infarcts (BIs) have individually been related to stroke, dementia, and mortality in population-based studies, mainly in older people. Their significance in middle-aged community-dwelling persons and the relative importance of these associations remain unclear. We simultaneously assessed the relation of white matter hyperintensities and BI with incident stroke, mild cognitive impairment, dementia, and mortality in a middle-aged community-based cohort., Methods: A total of 2229 Framingham Offspring Study participants aged 62+/-9 years underwent volumetric brain MRI and neuropsychological testing (1999 to 2005). Incident stroke, dementia, and mortality were prospectively ascertained and for 1694 participants in whom a second neuropsychological assessment was performed (2005 to 2007), incident mild cognitive impairment was evaluated. All outcomes were related to white matter hyperintensities volume (WMHV), age-specific extensive WMHV and BI adjusting for age and gender., Results: Extensive WMHV and BI were associated with an increased risk of stroke (hazard ratio [HR]=2.28, 95% CI: 1.02 to 5.13; HR=2.84, 95% CI: 1.32 to 6.10). WMHV, extensive WMHV, and BI were associated with an increased risk of dementia (HR=2.22, 95% CI: 1.32 to 3.72; HR=3.97, 95% CI: 1.10 to 14.30; HR=6.12, 95% CI: 1.82 to 20.54) independently of vascular risk factors and interim stroke. WMHV and extensive WMHV were associated with incident amnestic mild cognitive impairment in participants aged > or = 60 years only (OR=2.47, 95% CI: 1.31 to 4.66 and OR=1.49, 95% CI: 1.14 to 1.97). WMHV and extensive WMHV were associated with an increased risk of death (HR=1.38, 95% CI: 1.13 to 1.69; HR=2.27, 95% CI: 1.41 to 3.65) independent of vascular risk factors and of interim stroke and dementia., Conclusions: In a large community-based sample of middle-aged adults, BI predicted an increased risk of stroke and dementia independent of vascular risk factors. White matter hyperintensities portended an increased risk of stroke, amnestic mild cognitive impairment, dementia, and death independent of vascular risk factors and interim vascular events.

Background and Purpose: Previous studies examining genetic associations with MRI-defined brain infarct have yielded inconsistent findings. We investigated genetic variation underlying covert MRI infarct in persons without histories of transient ischemic attack or stroke. We performed meta-analysis of genome-wide association studies of white participants in 6 studies comprising the Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE) consortium., Methods: Using 2.2 million genotyped and imputed single nucleotide polymorphisms, each study performed cross-sectional genome-wide association analysis of MRI infarct using age- and sex-adjusted logistic regression models. Study-specific findings were combined in an inverse-variance-weighted meta-analysis, including 9401 participants with mean age 69.7 (19.4% of whom had >or=1 MRI infarct)., Results: The most significant association was found with rs2208454 (minor allele frequency, 20%), located in intron 3 of MACRO domain containing 2 gene and in the downstream region of fibronectin leucine-rich transmembrane protein 3 gene. Each copy of the minor allele was associated with lower risk of MRI infarcts (odds ratio, 0.76; 95% confidence interval, 0.68-0.84; P=4.64x10(-7)). Highly suggestive associations (P<1.0x10(-5)) were also found for 22 other single nucleotide polymorphisms in linkage disequilibrium (r(2)>0.64) with rs2208454. The association with rs2208454 did not replicate in independent samples of 1822 white and 644 black participants, although 4 single nucleotide polymorphisms within 200 kb from rs2208454 were associated with MRI infarcts in the black population sample., Conclusions: This first community-based, genome-wide association study on covert MRI infarcts uncovered novel associations. Although replication of the association with top single nucleotide polymorphisms failed, possibly because of insufficient power, results in the black population sample are encouraging, and further efforts at replication are needed.

Background and Purpose: Asymmetrical dimethylarginine (ADMA), an inhibitor of endothelial nitric oxide synthase, is a marker of endothelial dysfunction. Elevated circulating ADMA concentrations have been associated with systemic and carotid atherosclerosis, an elevated risk of developing stroke, and magnetic resonance imaging white-matter hyperintensities (WMHs). The relation of plasma ADMA to subclinical vascular brain injury has not been previously studied in a middle-aged, community-based sample., Methods: In 2013 stroke-free Framingham offspring (mean+/-SD age, 58+/-9.5 years; 53% women), we related baseline plasma ADMA levels (1995-1998) to subsequent brain magnetic resonance imaging measures (1999-2004) of subclinical vascular injury: presence of silent brain infarcts (SBIs) and large white-matter hyperintensity volumes (LWMHs; defined as >1 SD above the age-specific mean)., Results: Prevalences of SBIs and LWMHs were 10.7% and 12.6%, respectively. In multivariable analyses adjusting for age, sex and traditional stroke risk factors, higher ADMA levels were associated with an increased risk of prevalent SBIs (odds ratio [OR] per 1-SD increase in ADMA=1.16; 95% CI, 1.01 to 1.33; P=0.04). We observed that participants in the upper 3 age-specific quartiles (Qs) of plasma ADMA values had an increased prevalence of SBIs (OR for Q2-Q4 vs Q1=1.43; 95% CI, 1.00 to 2.04; P<0.05). The prevalence of SBIs in Q1and Q2-Q4 was 8.3% and 11.6%, respectively. The prevalence of LWMHs did not differ according to ADMA concentrations., Conclusions: Higher plasma ADMA values were associated with an increased prevalence of SBIs, after adjustment for traditional stroke risk factors. Thus, ADMA may be a potentially useful new biomarker of subclinical vascular brain injury, which is an important correlate of vascular cognitive impairment and risk of stroke.

Background and Purpose: Stroke is emerging as a major public health problem for women, as it is for men. Controversy persists regarding gender differences in stroke incidence, severity, and poststroke disability., Methods: Participants in the Framingham Original (n=5119; 2829 women) and Offspring (n=4957, 2565 women) cohorts who were 45 years and stroke-free were followed to first incident stroke. Gender-specific outcome measures were adjusted for the Framingham Stroke Risk Profile components., Results: We observed 1136 incident strokes (638 in women) over 56 years of follow-up. Women were significantly (P<0.001) older (75.1 versus 71.1 years for men) at their first-ever stroke, had a higher stroke incidence above 85 years of age, lower at all other ages, and a higher lifetime risk of stroke at all ages. There was no significant difference in stroke subtype, stroke severity, and case fatality rates between genders. Women were significantly (P<0.01) more disabled before stroke and in the acute phase of stroke in dressing (59% versus 37%), grooming (57% versus 34%), and transfer from bed to chair (59% versus 35%). At 3 to 6 months poststroke women were more disabled, more likely to be single, and 3.5 times more likely to be institutionalized (P<0.01)., Conclusions: These results from the Framingham Heart Study (FHS) support the existence of gender-differences in stroke incidence, lifetime risk (LTR) of stroke, age at first stroke, poststroke disability, and institutionalization rates. Prestroke disability and sociodemographic factors may contribute to the high rate of institutionalization and poorer outcome observed in women.

Background and Purpose: Women have increased lifetime stroke risk and more disabling strokes compared with men. Insights into the association between menopause and stroke could lead to new prevention strategies for women. The objective of this study was to examine the association of age at natural menopause with ischemic stroke risk in the Framingham Heart Study., Methods: Participants included women who survived stroke-free until age 60, experienced natural menopause, did not use estrogen before menopause, and who had complete data (n=1430). Participants were followed until first ischemic stroke, death, or end of follow-up (2006). Age at natural menopause was self-reported. Cox proportional hazards models were used to examine the association between age at natural menopause (<42, 42 to 54, >or=55) and ischemic stroke risk adjusted for age, systolic blood pressure, atrial fibrillation, diabetes, current smoking, cardiovascular disease and estrogen use., Results: There were 234 ischemic strokes identified. Average age at menopause was 49 years (SD=4). Women with menopause at ages 42 to 54 (hazard ratio=0.50; 95% CI: 0.29 to 0.89) and at ages >or=55 (hazard ratio=0.31; 95% CI: 0.13 to 0.76) had lower stroke risk compared with those with menopause <42 years adjusted for covariates. Women with menopause before age 42 had twice the stroke risk compared to all other women (hazard ratio=2.03; 95% CI: 1.16 to 3.56)., Conclusions: In this prospective study, age at natural menopause before age 42 was associated with increased ischemic stroke risk. Future stroke studies with measures of endogenous hormones are needed to inform the underlying mechanisms so that novel prevention strategies for midlife women can be considered.

Background and Purpose: Previous estimates of the prevalence of silent cerebral infarction (SCI) on MRI in community-based samples have varied between 5.8% and 17.7% depending on age, ethnicity, presence of comorbidities, and imaging techniques. We document the prevalence and risk factors associated with SCI at midlife in the community-based Framingham sample., Methods: Our study sample comprised 2040 Framingham Offspring (53% female; mean age, 62+/-9 years) who attended the sixth examination (1996-1998), underwent volumetric brain MRI (1999-2005,) and were free of clinical stroke at MRI. We examined the age- and sex-specific prevalences and the clinical correlates of SCI using multivariable logistic regression models., Results: At least 1 SCI was present in 10.7% of participants; 84% had a single lesion. SCI was largely located in the basal ganglia (52%), other subcortical (35%) areas, and cortical areas (11%). Prevalent SCI was associated with the Framingham Stroke Risk Profile score (OR, 1.27; 95% CI, 1.10-1.46); stage I hypertension was determined by JNC-7 criteria (OR,1.56; CI,1.15-2.11), an elevated plasma homocysteine in the highest quartile (OR, 2.23; CI, 1.42-3.51), atrial fibrillation (OR, 2.16; CI, 1.07-4.40), carotid stenosis >25% (OR, 1.62; 1.13-2.34), and increased carotid intimal-medial thickness above the lowest quintile (OR, 1.65; CI, 1.22-2.24)., Conclusions: The prevalence and distribution of SCI in the Framingham Offspring are comparable to previous estimates. Risk factors previously associated with clinical stroke were also found to be associated with midlife SCI. Our results support current guidelines emphasizing early detection and treatment of stroke risk factors.

Background and Purpose: Emerging evidence raises the possibility of an association between depression and stroke risk. This study sought to examine whether depressive symptoms are associated with an increased risk of cerebrovascular events in a community-based sample., Methods: A prospective study was conducted on 4120 Framingham Heart Study participants aged 29 to 100 years with up to 8 years of follow-up. The Center for Epidemiologic Studies Depression Scale was used to measure depressive symptoms. Incident stroke and transient ischemic attack (TIA) events were assessed by uniform diagnostic criteria. The association between depressive symptoms and risk of stroke/TIA was analyzed with Cox proportional-hazards models, after adjusting for traditional stroke risk factors., Results: In participants <65 years, the risk of developing stroke/TIA was 4.21 times greater (P= <0.001) in those with symptoms of depression. After adjusting for components of the Framingham Stroke Risk Profile (hazard ratio=3.43, 95% CI=1.60 to 7.36, P=0.002) and education (hazard ratio=4.89, 95% CI=2.19 to 10.95), similar results were obtained. In subjects aged 65 and older, depressive symptoms were not associated with an increased risk of stroke/TIA. Taking antidepressant medications did not alter the risk associated with depressive symptoms., Conclusions: In this community-based study, depressive symptoms were an independent risk factor for incident stroke/TIA in individuals <65 years. These data suggest that identification of depressive symptoms at younger ages may have an impact on the primary prevention of stroke.

Background and Purpose: This guideline provides an overview of the evidence on various established and potential stroke risk factors and provides recommendations for the reduction of stroke risk., Methods: Writing group members were nominated by the committee chair on the basis of each writer's previous work in relevant topic areas and were approved by the American Heart Association Stroke Council's Scientific Statement Oversight Committee. The writers used systematic literature reviews (covering the time period since the last review published in 2001 up to January 2005), reference to previously published guidelines, personal files, and expert opinion to summarize existing evidence, indicate gaps in current knowledge, and when appropriate, formulate recommendations based on standard American Heart Association criteria. All members of the writing group had numerous opportunities to comment in writing on the recommendations and approved the final version of this document. The guideline underwent extensive peer review before consideration and approval by the AHA Science Advisory and Coordinating Committee., Results: Schemes for assessing a person's risk of a first stroke were evaluated. Risk factors or risk markers for a first stroke were classified according to their potential for modification (nonmodifiable, modifiable, or potentially modifiable) and strength of evidence (well documented or less well documented). Nonmodifiable risk factors include age, sex, low birth weight, race/ethnicity, and genetic factors. Well-documented and modifiable risk factors include hypertension, exposure to cigarette smoke, diabetes, atrial fibrillation and certain other cardiac conditions, dyslipidemia, carotid artery stenosis, sickle cell disease, postmenopausal hormone therapy, poor diet, physical inactivity, and obesity and body fat distribution. Less well-documented or potentially modifiable risk factors include the metabolic syndrome, alcohol abuse, drug abuse, oral contraceptive use, sleep-disordered breathing, migraine headache, hyperhomocysteinemia, elevated lipoprotein(a), elevated lipoprotein-associated phospholipase, hypercoagulability, inflammation, and infection. Data on the use of aspirin for primary stroke prevention are reviewed., Conclusions: Extensive evidence is available identifying a variety of specific factors that increase the risk of a first stroke and providing strategies for reducing that risk.

Background and Purpose: The lifetime risk (LTR) of stroke has not been reported for the United States population; such data would assist public education and health planning., Methods: Framingham Original cohort participants (n=4897) who were stroke- and dementia-free at 55 years of age were followed biennially for up to 51 years (115 146 person years). We estimated the sex-specific 10-, 20-, and 30-year risks and LTR of developing a stroke by baseline age and blood pressure (BP) and compared it with the risk of developing Alzheimer disease (AD)., Results: A total of 875 participants (522 women) developed a first-ever stroke; 749 (448 women) had an ischemic stroke. LTR of stroke was high and remained similar at ages 55, 65, and 75 years, approximating 1 in 5 for women and 1 in 6 for men. Participants with a normal BP (<120/80 mm Hg) had approximately half the LTR of stroke compared with those with high BP (> or =140/90 mm Hg). The LTR of AD at age 65 (292 participants; 211 women) approximated 1 in 5 for women and 1 in 10 for men. The LTR of developing either stroke or dementia approximated 1 in 3 in both sexes., Conclusions: The LTR of stroke in middle-aged adults is 1 in 6 or more, which is equal to or greater than the LTR of AD. Women had a higher risk because of longer life expectancy. BP is a significant determinant of the LTR of stroke, and promotion of normal BP levels in the community might be expected to substantially reduce this risk.

The aim of this new statement is to provide comprehensive and timely evidence-based recommendations on the prevention of ischemic stroke among survivors of ischemic stroke or transient ischemic attack. Evidence-based recommendations are included for the control of risk factors, interventional approaches for atherosclerotic disease, antithrombotic treatments for cardioembolism, and the use of antiplatelet agents for noncardioembolic stroke. Further recommendations are provided for the prevention of recurrent stroke in a variety of other specific circumstances, including arterial dissections; patent foramen ovale; hyperhomocysteinemia; hypercoagulable states; sickle cell disease; cerebral venous sinus thrombosis; stroke among women, particularly with regard to pregnancy and the use of postmenopausal hormones; the use of anticoagulation after cerebral hemorrhage; and special approaches for the implementation of guidelines and their use in high-risk populations.

Background and Purpose: Identification of risk factors for dementia after stroke is best performed in comparison with stroke-free controls, because older subjects at high risk for stroke also have a substantial risk of dementia in the absence of stroke. Previous case-control studies were hospital-based. We used a nested case-control design to prospectively evaluate these risk factors in the community-based Framingham Study cohort., Methods: We compared 212 subjects who were free of dementia in January 1982 and sustained a first stroke after this date, with 1060 age- and sex-matched, stroke- and dementia-free controls. We calculated 10-year risks of dementia (by Diagnostic and Statistical Manual of Mental Disorders, Volume IV criteria) developing in cases and controls and also estimated the hazard ratios within subgroups defined by exposure to various demographic factors (age, gender, education), stroke-related features (right or left hemisphere, stroke type, second stroke), stroke risk factors (hypertension, diabetes, atrial fibrillation, smoking) and apolipoprotein E genotype., Results: Dementia developed in 19.3% of cases and 11.0% of controls. Baseline stroke doubled the risk of dementia (hazard ratio [HR]: 2.0; 95% confidence interval [CI]: 1.5 to 3.1) and adjustment for age, sex, education, and exposure to individual stroke risk factors did not diminish the risk (HR: 2.4; 95% CI: 1.6 to 3.7). The HR was higher in younger subjects (age younger than 80 years [HR: 2.6; 95% CI: 1.5 to 4.5]), apolipoprotein E 3/3 homozygotes (HR: 3.4; 95% CI: 2.0 to 5.8), and high school graduates (HR: 2.4; 95% CI: 1.5 to 3.9)., Conclusions: Stroke increases a subject's risk of dementia as compared with age- and sex-matched controls. Primary and secondary prevention of stroke should significantly decrease the risk of all dementia.

Background and Purpose: The American Stroke Association (ASA) assembled a multidisciplinary group of experts to develop recommendations regarding the potential effectiveness of establishing an identification program for stroke centers and systems. "Identification" refers to the full spectrum of models for assessing and recognizing standards of quality care (self-assessment, verification, certification, and accreditation). A primary consideration is whether stroke center identification might improve patient outcomes., Methods: In February 2001, ASA, with the support of the Stroke Council's Executive Committee, decided to embark on an evaluation of the potential impact of stroke center identification. HealthPolicy R&D was selected to prepare a comprehensive report. The investigators reported on models outside the area of stroke, ongoing initiatives within the stroke community (such as Operation Stroke), and state and federal activities designed to improve care for stroke patients. The investigators also conducted interviews with thought leaders in the stroke community, representing a diverse sampling of specialties and affiliations. In October 2001, the Advisory Working Group on Stroke Center Identification developed its consensus recommendations. This group included recognized experts in neurology, emergency medicine, emergency medical services, neurological surgery, neurointensive care, vascular disease, and stroke program planning., Results: There are a variety of existing identification programs, generally falling within 1 of 4 categories (self-assessment, verification, certification, and accreditation) along a continuum with respect to intensity and scope of review and consumption of resources. Ten programs were evaluated, including Peer Review Organizations, trauma centers, and new efforts by the National Committee on Quality Assurance and the Joint Commission on the Accreditation of Healthcare Organizations to identify providers and disease management programs. The largest body of literature on clinical outcomes associated with identification programs involves trauma centers. Most studies support that trauma centers and systems lead to improved mortality rates and patient outcomes. The Advisory Working Group felt that comparison to the trauma model was most relevant given the need for urgent evaluation and treatment of stroke. The literature in other areas generally supports the positive impact of identification programs, although patient outcomes data have less often been published. In the leadership interviews, participants generally expressed strong support for pursuing some form of voluntary identification program, although concerns were raised that this effort could meet with some resistance., Conclusions: Identification of stroke centers and stroke systems competencies is in the best interest of stroke patients in the United States, and ASA should support the development and implementation of such processes. The purpose of a stroke center/systems identification program is to increase the capacity for all hospitals to treat stroke patients according to standards of care, recognizing that levels of involvement will vary according to the resources of hospitals and systems.