Differential Impact of Index Stroke on Dementia Risk in African-Americans Compared to Whites.

OBJECTIVE: To compare whites and African-Americans in terms of dementia risk following index stroke. METHODS: The data consisted of billing and International Classification of Diseases, Ninth Revision diagnosis codes from the South Carolina Revenue and Fiscal Affairs office on all hospital discharges within the state between 2000 and 2012. The sample consisted of 68,758 individuals with a diagnosis of ischemic stroke prior to 2010 (49,262 white [71.65%] and 19,496 African-Americans [28.35%]). We identified individuals in the dataset who were subsequently diagnosed with any of 5 categories of dementia and evaluated time to dementia diagnosis in Cox Proportional Hazards models. We plotted cumulative hazard curves to illustrate the effect of race on dementia risk after controlling for age, sex, and occurrence of intervening stroke. RESULTS: Age at index stroke was significantly different between the 2 groups, with African-Americans being younger on average (70.0 [SD 12.5] in whites versus 64.5 [SD 14.1] in African-Americans, P < .0001). Adjusted hazard ratios revealed that African-American race increased risk for all 5 categories of dementia following incident stroke, ranging from 1.37 for AD to 1.95 for vascular dementia. Age, female sex, and intervening stroke likewise increased risk for dementia. CONCLUSIONS: African-Americans are at higher risk for dementia than whites within 5 years of ischemic stroke, regardless of dementia subtype. Incident strokes may have a greater likelihood of precipitating dementia in African-Americans due to higher prevalence of nonstroke cerebrovascular disease or other metabolic or vascular factors that contribute to cognitive impairment.

Role of mHealth in overcoming the occurrence of post-stroke depression.

Depression associated with stroke affects roughly one-third of stroke survivors. Post-stroke depression (PSD) is thought to adversely influence functional outcome by limiting participation in rehabilitation, decreasing physical, social, and cognitive function, and affecting neuroplasticity thereby placing stroke survivors at high risk for future vascular events. PSD has also been associated with higher mortality rates after stroke. In Peru, a country where there is no national stroke program and mental health disorders are largely underdiagnosed and untreated, people with PSD are likely to be further challenged by dependency and impoverished conditions that will limit their use of ambulatory services, leading to inadequate clinical follow-up. In this scenario, mobile health (mHealth) technology offers a promising approach to extend access to high-quality and culturally tailored evidence-based psychological care to address PSD given that cell phone use, Internet connectivity, and digital health technology have met a rapid growth in the last years and thus contribute to the attainment of broader Sustainable Development Goals (SDGs). The limited evidence of the effectiveness of mHealth for PSD calls for researchers to fill a knowledge gap where Peru poses as an ideal setting because rapid expansion of digital technology and current mental healthcare reform could be leveraged to enhance post-stroke outcomes. This article proposes the rationale for a suitable evidence-driven, mHealth-based, PSD self-management intervention called iMOODS-Investigating the role of mHealth in overcoming occurrence of depression after stroke-that could be tested among recent stroke patients with PSD in resource constrained settings.

APOL1, CDKN2A/CDKN2B, and HDAC9 polymorphisms and small vessel ischemic stroke.

OBJECTIVE: Worldwide, the highest frequencies of APOL1-associated kidney variants are found in indigenous West Africans among whom small vessel disease (SVD) ischemic stroke is the most common stroke phenotype. The objective of this study was to investigate the association and effect sizes of 23 selected SNPs in 14 genes of relevance, including the APOL1 G1 variants, with the occurrence of SVD ischemic stroke among indigenous West African participants in the Stroke Investigative Research and Education Network (SIREN) Study. MATERIALS AND METHODS: Cases were consecutively recruited consenting adults (aged 18 years or older) with neuroimaging-confirmed first clinical stroke. Stroke-free controls were ascertained using a locally validated version of the Questionnaire for Verifying Stroke-Free Status (QVSFS). Logistic regression models adjusting for known vascular risk factors were fitted to assess the associations of the 23 SNPs in rigorously phenotyped cases (N = 154) of SVD ischemic stroke and stroke-free (N = 483) controls. RESULTS: Apolipoprotein L1 (APOL1) rs73885319 (OR = 1.52; CI: 1.09-2.13, P-value = .013), rs2383207 in CDKN2A/CDKN2B (OR = 3.08; CI: 1.15-8.26, P -value = .026) and rs2107595 (OR = 1.70; CI: 1.12-2.60, P-value = .014) and rs28688791 (OR = 1.52; CI: 1.03-2.26, P-value = .036) in HDAC9 gene were associated with SVD stroke at 0.05 significance level. Polymorphisms in other genes did not show significant associations. CONCLUSION: This is the first report of a specific association of APOL1 with a stroke subtype. Further research is needed to confirm these initial findings and deepen understanding of the genetics of stroke in people of African ancestry with possible implications for other ancestries as all humans originated from Africa.

Stroke Investigative Research and Education Network: Public Outreach and Engagement.

Stroke is becoming a leading cause of disability and death, and a major public health concern in Sub-Saharan Africa (SSA). The Stroke Investigative Research and Education Network (SIREN) seeks to comprehensively characterize the genomic, sociocultural, economic, and behavioral risk factors for stroke and to build effective teams for research to address and decrease the burden of stroke and other non-communicable diseases in SSA. One of the first steps to address this goal was to effectively engage the communities that suffer high burdens of disease in SSA. This paper describes the process of SIREN project's community engagement activities in Ghana and Nigeria. The aims of community engagement (CE) within SIREN are to: i) elucidate information about knowledge, attitudes, beliefs, and practices (KABP) about stroke and its risk factors from individuals of African ancestry in SSA; ii) educate the community about stroke and ways to decrease disabilities and deaths from stroke; and iii) recruit 3000 control research subjects to participate in a case-control stroke study. CE focused on three-pronged activities-constitution and interaction with Community Advisory Board (CABs), Focus Group Discussions (n=27) and community education and outreach programs (n=88). FGDs and outreach programs indicate that knowledge of stroke, as well as risk factors and follow-up evidence-based care is limited and often late. Almost all indicated that genetic testing could help health provider's better treat stroke and help scientists better understand the causes of stroke. Over 7000 individuals have received education on cardiovascular risk factors and about 5,000 have been screened for cardiovascular risk factors during the outreaches. The CE core within SIREN is a first of its kind public outreach engagement initiative to evaluate and address perceptions about stroke and genomics by patients, caregivers, and local leaders in SSA and has implications as a model for assessment in other high stroke risk populations.

Post-stroke diastolic blood pressure and risk of recurrent vascular events.

BACKGROUND AND PURPOSE: Recent clinical trials and expert consensus guidelines have typically focused on the issue of systolic blood pressure (SBP) targets for reducing vascular risk. However, little is known about the relationship of the diastolic BP (DBP) level with vascular outcomes after a stroke. METHODS: A multicenter trial dataset involving 3680 recent (<4 months) non-cardioembolic stroke patients followed for 2 years was analyzed. Subjects were categorized per mean DBP level (mmHg) during follow-up: low-normal (<70), normal (70 to <80), high-normal (80-89) and high (≥90). Pulse pressure (PP) was prespecified by three categories of <60, 60 to <70, and ≥70 mmHg. Independent associations of mean DBP level with major vascular events (MVEs) and ischaemic stroke were assessed. RESULTS: Major vascular events occurred in 20.7% of the low-normal, 15.1% of the normal, 16.9% of the high-normal and 19.2% of the high DBP groups, whilst stroke occurred in 9.9%, 6.8%, 8.5% and 10.8%, respectively. Compared with the normal DBP group, risk of MVEs was higher in the low-normal DBP group (adjusted hazard ratio 1.33; 95% confidence interval 1.04-1.71). Amongst those with SBP 120 to <140 mmHg, risk of MVEs (1.89; 1.13-3.15) and stroke (2.87; 1.48-5.53) was higher in subjects with PP ≥70 (mean DBP 62.4 ± 3.8) than those with the lowest PP (mean DBP 78.0 ± 5.9) whilst, amongst those with SBP <120 mmHg, PP 60 to <70 (mean DBP 52.7 ± 2.5) was associated with increased risk of stroke (5.85; 1.25-27.5). CONCLUSION: Diastolic BP levels in the low-normal range, particularly accompanied by an increased PP of >60, confer increased risk of MVEs and stroke amongst patients after recent non-cardioembolic stroke.

Prevalence and predictors of anxiety in an African sample of recent stroke survivors.

OBJECTIVES: Studies considering emotional disturbances in the setting of stroke have primarily focused on depression and been conducted in high-income countries. Anxiety in stroke survivors, which may be associated with its own unique sets of risk factors and clinical parameters, has been rarely investigated in sub-Saharan Africa (SSA). We assess the characteristics of anxiety and anxiety-depression comorbidity in a SSA sample of recent stroke survivors. MATERIALS AND METHODS: We assessed baseline data being collected as part of an intervention to improve one-year blood pressure control among recent (≤1 month) stroke survivors in SSA. Anxiety in this patient population was measured using the Hospital Anxiety and Depression Scale (HADS), while the community screening instrument for dementia was used to evaluate cognitive functioning. Independent associations were assessed using logistic regression analysis. RESULTS: Among 391 participants, clinically significant anxiety (HADS anxiety score≥11) was found in 77 (19.7%). Anxiety was comorbid with depression in 55 (14.1%). Female stroke survivors were more likely than males to have anxiety (OR=2.4, 95% CI=1.5-4.0). Anxiety was significantly associated with the presence of cognitive impairment after adjusting for age, gender and education (OR=6.8, 95% CI=2.6-18.0). CONCLUSIONS: One in five recent stroke survivors in SSA has clinically significant anxiety, and well over 70% of those with anxiety also have depression. Future studies will need to determine what specific impact post-stroke anxiety may have on post-stroke clinical processes and outcomes.

Relationship of functional disability after a recent stroke with recurrent stroke risk.

BACKGROUND AND PURPOSE: Post-stroke disability status is primarily focused on recovery prognostication but the influence of post-stroke disability on future vascular risk is unknown. The relationship between functional disability after an index stroke and risk of recurrent vascular events was examined. METHODS: A cohort analysis of 3680 recent non-cardioembolic, non-to-moderate disabled [modified Rankin Scale (mRS) ≤3] stroke patients aged ≥35 years and followed for 2 years was reviewed. The mRS measured at a median of 35 days after the index stroke was analyzed as a dichotomous variable (mRS 3 vs. ≤2) and in a stepwise manner. Independent associations of post-stroke disability by mRS score with ischaemic stroke (primary outcome), stroke/coronary heart disease/vascular death as major vascular events (secondary outcome) and all-cause death (tertiary outcome) were analyzed. RESULTS: Amongst study participants, 435 (11.8%) had an mRS of 3. Compared with mRS ≤2 as no/slight disability, mRS 3 as moderate disability was associated with a higher risk of stroke (adjusted hazard ratio 1.45, 95% confidence interval 1.06-1.99). Compared with mRS 0, there was a progressively higher independent risk for each of the study outcomes: stroke, mRS 1 (1.42, 0.97-2.08), mRS 2 (1.46, 0.97-2.20), mRS 3 (1.89, 1.20-2.97); major vascular events, mRS 1 (1.31, 1.01-1.70), mRS 2 (1.31, 0.99-1.74), mRS 3 (1.46, 1.06-2.01); and all-cause death, mRS 1 (1.75, 1.03-2.98), mRS 2 (2.49, 1.44-4.31), mRS 3 (2.72, 1.43-5.19). CONCLUSION: Compared with no/slight disability, moderate disability after a recent stroke is linked to a higher risk of recurrent stroke.

Stroke genomics in people of African ancestry: charting new paths.

One in six people worldwide will experience a stroke in his/her lifetime. While people in Africa carry a disproportionately higher burden of poor stroke outcomes, compared to the rest of the world, the exact contribution of genomic factors to this disparity is unknown. Despite noteworthy research into stroke genomics, studies exploring the genetic contribution to stroke among populations of African ancestry in the United States are few. Furthermore, genomics data in populations living in Africa are lacking. The wide genomic variation of African populations offers a unique opportunity to identify genomic variants with causal relationships to stroke across different ethnic groups. The Stroke Investigative Research and Educational Network (SIREN), a component of the Human Health and Heredity in Africa (H3Africa) Consortium, aims to explore genomic and environmental risk factors for stroke in populations of African ancestry in West Africa and the United States. In this article, we review the literature on the genomics of stroke with particular emphasis on populations of African origin.

Contribution and additional impact of imaging to the SPAN-100 score.

BACKGROUND AND PURPOSE: Stroke Prognostication by Using Age and NIHSS score (SPAN-100 index) facilitates stroke outcomes. We assessed imaging markers associated with the SPAN-100 index and their additional impact on outcome determination. MATERIALS AND METHODS: Of 273 consecutive patients with acute ischemic stroke (<4.5 hours), 55 were characterized as SPAN-100-positive (age +NIHSS score ≥ 100). A comprehensive imaging review evaluated differences, using the presence of the hyperattenuated vessel sign, ASPECTS, clot burden score, collateral score, CBV, CBF, and MTT. The primary outcome assessed was favorable outcome (mRS ≤ 2). Secondary outcomes included recanalization, lack of neurologic improvement, and hemorrhagic transformation. Uni- and multivariate analyses assessed factors associated with favorable outcome. Area under the curve evaluated predictors of favorable clinical outcome. RESULTS: Compared with the SPAN-100-negative group, the SPAN-100-positive group (55/273; 20%) demonstrated larger CBVs (<0.001), poorer collaterals (P < .001), and increased hemorrhagic transformation rates (56.0% versus 36%, P = .02) despite earlier time to rtPA (P = .03). Favorable outcome was less common among patients with SPAN-100-positive compared with SPAN-100-negative (10.9% versus 42.2%; P < .001). Multivariate regression revealed poorer outcome for SPAN-100-positive (OR = 0.17; 95% CI, 0.06-0.38; P = .001), clot burden score (OR = 1.14; 95% CI, 1.05-1.25; P < .001), and CBV (OR = 0.58; 95% CI, 0.46-0.72; P = .001). The addition of the clot burden score and CBV improved the predictive value of SPAN-100 alone for favorable outcome from 60% to 68% and 74%, respectively. CONCLUSIONS: SPAN-100-positivity predicts a lower likelihood of favorable outcome and increased hemorrhagic transformation. CBV and clot burden score contribute to poorer outcomes among high-risk patients and improve stroke-outcome prediction.

Association of intracranial atherosclerotic stenosis with severity of white matter hyperintensities.

BACKGROUND AND PURPOSE: White matter hyperintensities (WMHs) on magnetic resonance imaging (MRI) have been linked to small-vessel disease, but the precise pathogenesis underlying WMHs remains unclear. Studies about an association of WMHs with extracranial atherosclerotic stenosis (ECAS) showed conflicting results and the relationship of WMHs with intracranial atherosclerotic stenosis (ICAS) is uncertain. METHODS: A cross-sectional study of 679 consecutive Korean patients with acute ischaemic stroke (mean age 67.8 ± 12.6; 395 males) who underwent brain MRI/MR angiography was conducted. Severity of deep WMHs (d-WMHs, n = 560) and periventricular WMHs (p-WMHs, n = 590) was rated separately and compared across three groups: ICAS (n = 318), ECAS (n = 71) and no cerebral atherosclerotic stenosis (NCAS) (n = 290). RESULTS: The ICAS group showed a higher d-WMH/p-WMH score (1.62 ± 0.85/1.65 ± 0.79) than both the ECAS (1.25 ± 0.87/1.23 ± 0.78) and NCAS (1.19 ± 0.92/1.24 ± 0.81) groups (P < 0.001 for all). Patients with a greater number of ICAS were more likely to have higher scores of d-WMH/p-WMH (P < 0.001 for all). Patients with higher scores of d-WMH/p-WMH had a higher incidence of ICAS (P < 0.001 for all), but not of ECAS or NCAS. In multivariable analysis, a dose-response relationship was observed between the extent of ICAS versus WMHs. Compared with one ICAS lesion, for d-WMHs the odds ratio (OR) = 2.61 [95% confidence interval (CI) 0.95-7.20] for two ICAS lesions and OR = 3.37 (1.10-10.32) for ≥3 ICAS lesions; whilst for p-WMHs (score ≥2) OR = 1.70 (95% CI 0.96-2.98) for two ICAS lesions and OR = 2.02 (1.15-3.55) for ≥3 ICAS lesions. CONCLUSION: ICAS is independently associated with progressively greater WMH burden. The association of ICAS with WMH severity appears to be stronger than that of ECAS/NCAS in the Korean (Asian) stroke population.

Secondary preventive medication persistence and adherence 1 year after stroke.

OBJECTIVE: Data on long-term use of secondary prevention medications following stroke are limited. The Adherence eValuation After Ischemic stroke-Longitudinal (AVAIL) Registry assessed patient, provider, and system-level factors influencing continuation of prevention medications for 1 year following stroke hospitalization discharge. METHODS: Patients with ischemic stroke or TIA discharged from 106 hospitals participating in the American Heart Association Get With The Guidelines-Stroke program were surveyed to determine their use of warfarin, antiplatelet, antihypertensive, lipid-lowering, and diabetes medications from discharge to 12 months. Reasons for stopping medications were ascertained. Persistence was defined as continuation of all secondary preventive medications prescribed at hospital discharge, and adherence as continuation of prescribed medications except those stopped according to health care provider instructions. RESULTS: Of the 2,880 patients enrolled in AVAIL, 88.4% (2,457 patients) completed 1-year interviews. Of these, 65.9% were regimen persistent and 86.6% were regimen adherent. Independent predictors of 1-year medication persistence included fewer medications prescribed at discharge, having an adequate income, having an appointment with a primary care provider, and greater understanding of why medications were prescribed and their side effects. Independent predictors of adherence were similar to those for persistence. CONCLUSIONS: Although up to one-third of stroke patients discontinued one or more secondary prevention medications within 1 year of hospital discharge, self-discontinuation of these medications is uncommon. Several potentially modifiable patient, provider, and system-level factors associated with persistence and adherence may be targets for future interventions.

Presence of baseline prehypertension and risk of incident stroke: a meta-analysis.

OBJECTIVE: To qualitatively and quantitatively assess the association of prehypertension with incident stroke through a meta-analysis of prospective cohort studies. METHODS: We searched Medline, Embase, the Cochrane Library, and bibliographies of retrieved articles. Prospective cohort studies were included if they reported multivariate-adjusted relative risks (RRs) and corresponding 95%confidence intervals (CI) of stroke with respect to baseline prehypertension. RESULTS: Twelve studies with 518,520 participants were included. Prehypertension was associated with risk of stroke (RR 1.55, 95% CI 1.35-1.79; p < 0.001). Seven studies further distinguished a low prehypertensive population (systolic blood pressure [SBP] 120-129 mm Hg or diastolic blood pressure [DBP] 80-84 mm Hg) and a high prehypertensive population (SBP 130-139 mm Hg or DBP 85-89 mm Hg). Among persons with lower-range prehypertension, stroke risk was not significantly increased (RR 1.22, 0.95-1.57). However, for persons with higher values within the prehypertensive range, stroke risk was substantially increased (RR 1.79, 95% CI 1.49-2.16). CONCLUSIONS: Prehypertension is associated with a higher risk of incident stroke. This risk is largely driven by higher values within the prehypertensive range and is especially relevant in nonelderly persons. Randomized trials to evaluate the efficacy of blood pressure reduction in persons with this designation are warranted.

Angiography reveals that fluid-attenuated inversion recovery vascular hyperintensities are due to slow flow, not thrombus.

BACKGROUND AND PURPOSE: Fluid-attenuated inversion recovery (FLAIR) vascular hyperintensities (FVH) are commonly encountered on MR imaging studies performed shortly after the onset of acute ischemic stroke. Prior reports have speculated regarding the pathogenesis of this finding, yet definitive correlative angiographic studies have not been performed. We studied the pathophysiologic and hemodynamic correlates of FVH on conventional angiography and concurrent MR imaging sequences. MATERIALS AND METHODS: Retrospective review of FLAIR and gradient-refocused echo MR imaging sequences acquired immediately before conventional angiography for acute stroke was conducted in a blinded fashion. The presence, location, and morphology of FVH were noted and correlated with markers of thrombotic occlusion and collateral flow on angiography. Angiographic collaterals were graded on a 5-point scale incorporating extent and hemodynamic aspects. RESULTS: A prospective ischemic stroke registry of 632 patients was searched to identify 74 patients (mean age, 63.4 +/- 20 years; 48% women) having undergone FLAIR sequences immediately before angiography. Median time from FLAIR to angiography was 2.9 hours (interquartile range, 1.1-4.7 hours). FVH were present in 53/74 (72%) of all acute stroke cases with subsequent angiography. FVH distal to an arterial occlusion were associated with a high grade of leptomeningeal collateral blood flow. CONCLUSIONS: FVH are observed in areas of blood flow proximal and distal to stenosis or occlusion and are noted with more extensive collateral circulation.

Determinants of the distribution and severity of hypoperfusion in patients with ischemic stroke.

BACKGROUND: In acute cerebral ischemia, two variables characterize the extent of hypoperfusion: the volume of hypoperfused tissue and the intensity of hypoperfusion within these regions. We evaluated the determinants of the intensity of hypoperfusion within oligemic regions among patients who were eligible for recanalization therapy for acute ischemic stroke. METHODS: We analyzed data, including pretreatment diffusion-weighted imaging (DWI) and perfusion-weighted imaging, on 119 patients with acute middle cerebral artery infarctions. The intensity of hypoperfusion within oligemic regions was characterized by the hypoperfusion intensity ratio (HIR), defined as the volume of tissue with severe hypoperfusion (Tmax > or = 8 seconds) divided by the volume of tissue with any hypoperfusion (Tmax > or = 2 seconds). Based on the DWI data, we divided the patients into four stroke phenotypes: large cortical, small (< 1 cm diameter) cortical, border-zone, and deep pattern. RESULTS: The mean (SD) volume of severe hypoperfusion was 54.6 (52.5) mL, and that of any hypoperfusion was 140.8 (81.3) mL. The HIR ranged widely, from 0.002 to 0.974, with a median of 0.35 (interquartile range 0.13-0.60). The volume of any hypoperfusion did not predict the intensity of hypoperfusion within the affected region (r = 0.10, p = 0.284). Angiographic collateral flow grade was associated with HIRs (p value for trend = 0.019) and differed among DWI lesion patterns. In multivariate analysis, diastolic pressure on admission (odds ratio 0.959, 95% CI 0.922-0.998) and DWI pattern of deep infarcts (odds ratio 18.004 compared with large cortical pattern, 95% CI 1.855-173.807) were independently associated with a low HIR. CONCLUSIONS: The intensity of hypoperfusion within an oligemic field is largely independent of the size of the oligemia region. Predictors of lesser intensity of hypoperfusion are lower diastolic blood pressure and presence of a deep diffusion-weighted imaging lesion pattern.

Association of serum lipid indices with large artery atherosclerotic stroke.

BACKGROUND: Low-density lipoprotein cholesterol (LDL) is the primary lipid target for vascular risk reduction in stroke patients, but emerging data suggest that other lipid indices may better predict vascular hazard. We evaluated the relationship between several measures of the classically obtained serum lipid panel and the occurrence of large artery atherosclerotic stroke. METHODS: Data prospectively collected over a 4-year period on subjects admitted with ischemic stroke or TIA to a university medical center were analyzed. Independent associations of fasting serum lipid indices with large artery atherosclerotic (LAA) stroke mechanism were evaluated. RESULTS: Of 1,049 patients, 247 (23.5%) were classified with LAA, 224 (21.4%) were classified with small vessel disease (SVD), and 578 (55%) were non-LAA, non-SVD subtype. Lipid levels were similar between LAA and SVD patients. Total cholesterol, triglycerides, LDL, non-high-density lipoprotein cholesterol (HDL), and triglyceride:HDL ratio were significantly higher in LAA vs non-LAA, non-SVD patients. After adjustment for age, hypertension, diabetes, smoking, body mass index, and premorbid statin use, significant odds ratios (ORs) for LAA compared with all other ischemic stroke subtypes for patients in the uppermost lipid quartiles (vs lowest) were triglycerides (OR 2.69, 95% CI 1.44 to 5.02) and non-HDL (OR 2.39, 95% CI 1.40 to 4.11). LDL was not associated with LAA. CONCLUSIONS: Compared with all other ischemic stroke subtypes, elevated levels of serum triglycerides and non-high-density lipoprotein, but not low-density lipoprotein (LDL), are associated with large artery atherosclerotic stroke. These non-LDL lipid measures may have utility in delineating atherosclerotic stroke risk.

Impact of collateral flow on tissue fate in acute ischaemic stroke.

BACKGROUND: Collaterals may sustain penumbra prior to recanalisation yet the influence of baseline collateral flow on infarct growth following endovascular therapy remains unknown. METHODS: Consecutive patients underwent serial diffusion and perfusion MRI before and after endovascular therapy for acute cerebral ischaemia. We assessed the relationship between MRI diffusion and perfusion lesion indices, angiographic collateral grade and infarct growth. Tmax perfusion lesion maps were generated and diffusion-perfusion mismatch regions were divided into Tmax >or=4 s (severe delay) and Tmax >or=2 but <4 s (mild delay). RESULTS: Among 44 patients, collateral grade was poor in 7 (15.9%), intermediate in 20 (45.5%) and good in 17 (38.6%) patients. Although diffusion-perfusion mismatch volume was not different depending on the collateral grade, patients with good collaterals had larger areas of milder perfusion delay than those with poor collaterals (p = 0.005). Among 32 patients who underwent day 3-5 post-treatment MRIs, the degree of pretreatment collateral circulation (r = -0.476, p = 0.006) and volume of diffusion-perfusion mismatch (r = 0.371, p = 0.037) were correlated with infarct growth. Greatest infarct growth occurred in patients with both non-recanalisation and poor collaterals. Multiple regression analysis revealed that pretreatment collateral grade was independently associated with infarct growth. CONCLUSION: Our data suggest that angiographic collateral grade and penumbral volume interactively shape tissue fate in patients undergoing endovascular recanalisation therapy. These angiographic and MRI parameters provide complementary information about residual blood flow that may help guide treatment decision making in acute cerebral ischaemia.

Current strategies for ischemic stroke prevention: role of multimodal combination therapies.

Stroke remains a global leading cause of death and long-term disability, highlighting the need for more effective treatment approaches. The majority of strokes are of ischemic origin, often caused by large- or small-artery atherothrombosis, or cardioembolism. Considering the systemic nature of the atherothrombotic disease process, stroke patients are at increased risk for ischemic events in several vascular territories: cerebral, coronary and peripheral. Due to the limited options for acute stroke therapies, stroke prevention is an important therapeutic approach. In addition to the management of modifiable risk factors such as hypertension, dyslipidemia and smoking through pharmacotherapy or lifestyle adjustments, anticoagulants, surgical and perhaps endovascular approaches are indicated in certain patients. Antiplatelet therapies using various agents are a cornerstone of secondary stroke prevention. To ensure the appropriate continuum of care after hospitalization for ischemic stroke, some interventions for the prevention of recurrent ischemic stroke should be initiated during the acute hospitalization setting and maintained in the out-patient setting.

Statin enhancement of collateralization in acute stroke.

Collateral circulation influences cerebral infarction occurrence and size. Statins may improve ischemic stroke outcomes. We evaluated the relationship between prestroke statin use and pretreatment angiographic collateral grade among acute ischemic stroke patients presenting with occlusion of a major cerebral artery. After adjusting for covariates, the statin-treated group had significantly higher collateral scores than non-statin users, suggesting an association between statin use and better collateralization during acute stroke.

Adiponectin levels in patients with intracranial atherosclerosis.

BACKGROUND: Adiponectin is a protein secreted by adipose cells that improves insulin sensitivity and possesses antiatherogenic properties. In this study, we investigated the relationship between adiponectin levels and ischemic stroke subtype. METHODS: Using clinical, imaging, and laboratory data, 231 consecutive patients admitted to a university medical center over a 2-year period with acute cerebral infarcts were categorized into four subtypes: intracranial atherosclerosis (n = 67), extracranial atherosclerosis (n = 61), small arterial occlusion (n = 63), and cardioembolic (n = 40). Clinical features, risk factors including the presence of metabolic syndrome, and levels of s-adiponectin were compared between groups. RESULTS: Patients with more severe metabolic abnormalities were more likely to have lower s-adiponectin levels (p = 0.002). S-adiponectin levels differed by stroke subtype: highest in the cardioembolic group and lowest in the intracranial atherosclerosis group (8.42 +/- 5.07 vs 5.60 +/- 2.79 microg/mL, p = 0.01). Extracranial atherosclerosis (6.45 +/- 4.10 microg/mL) and small arterial occlusion (6.07 +/- 3.44 microg/mL) groups were intermediate. Patients with advanced intracranial atherosclerosis (> or =1 additional lesion outside the symptomatic arterial territory) had lower s-adiponectin levels than those with isolated intracranial atherosclerosis (4.95 +/- 2.63 vs 6.13 +/- 2.84 microg/mL, p = 0.003). In multiple regression analysis, s-adiponectin levels, but not metabolic syndrome, were independently associated with intracranial atherosclerosis. CONCLUSIONS: Symptomatic intracranial atherosclerosis is associated with lower s-adiponectin levels vs other ischemic stroke subtypes.