Browsing by Subject "Ischemic stroke"

Now showing 1 - 7 of 7
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    Association between admission haematocrit and mortality among men with acute ischaemic stroke
    (BMJ, 2018-04-24) Sico, Jason J.; Myers, Laura J.; Fenton, Brenda; Concato, John; Williams, Linda S.; Bravata, Dawn M.; Neurology, School of Medicine
    Objective: Anaemia is associated with higher mortality among patients with non-stroke cardiovascular conditions; less is known regarding the relationship between anaemia and mortality among patients with acute ischaemic stroke. Methods: Medical records were abstracted for n=3965 veterans from 131 Veterans Health Administration facilities who were admitted with ischaemic stroke in fiscal year 2007. Haematocrit values within 24 hours of admission were classified as ≤27%, 28%-32%, 33%-37%, 38%-42%, 43%-47% or ≥48%. Multivariate logistic regression was used to examine the relationship between anaemia and in-hospital, 30-day, 6-month and 1-year mortality, adjusting for age, medical comorbidities, modified Acute Physiology and Chronic Health Evaluation-III and stroke severity. Impact factors were calculated to standardise comparisons between haematocrit tier and other covariates. Results: Among n=3750 patients included in the analysis, the haematocrit values were ≤27% in 2.1% (n=78), 28%-32% in 6.2% (n=234), 33%-37% in 17.9% (n=670), 38%-42% in 36.4% (n=1366), 43%-47% in 28.2% (n=1059) and ≥48% in 9.1% (n=343). Patients with haematocrit ≤27%, compared with patients in the 38%-42% range, were more likely to have died across all follow-up intervals, with statistically significant adjusted ORs (aORs) ranging from 2.5 to 3.5. Patients with polycythaemia (ie, haematocrit ≥48%) were at increased risk of in-hospital mortality (aOR=2.9; 95% CI 1.4 to 6.0), compared with patients with mid-range admission haematocrits. Pronounced differences between patients receiving and not receiving blood transfusion limited our ability to perform a propensity analysis. Impact factors in the 1-year mortality model were 0.46 (severe anaemia), 0.06 (cancer) and 0.018 (heart disease). Conclusions: Anaemia is independently associated with an increased risk of death throughout the first year post stroke; high haematocrit is associated with early poststroke mortality. Severe anaemia is associated with 1-year mortality to a greater degree than cancer or heart disease. These data cannot address the question of whether interventions targeting anaemia might improve patient outcomes.
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    Development, Validation, and Assessment of an Ischemic Stroke or Transient Ischemic Attack-Specific Prediction Tool for Obstructive Sleep Apnea
    (Elsevier, 2017-08) Sico, Jason J.; Yaggi, H. Klar; Ofner, Susan; Concato, John; Austin, Charles; Ferguson, Jared; Qin, Li; Tobias, Lauren; Taylor, Stanley; Vaz Fragoso, Carlos A.; McLain, Vincent; Williams, Linda S.; Bravata, Dawn M.; Biostatistics, School of Public Health
    BACKGROUND: Screening instruments for obstructive sleep apnea (OSA), as used routinely to guide clinicians regarding patient referral for polysomnography (PSG), rely heavily on symptomatology. We sought to develop and validate a cerebrovascular disease-specific OSA prediction model less reliant on symptomatology, and to compare its performance with commonly used screening instruments within a population with ischemic stroke or transient ischemic attack (TIA). METHODS: Using data on demographic factors, anthropometric measurements, medical history, stroke severity, sleep questionnaires, and PSG from 2 independently derived, multisite, randomized trials that enrolled patients with stroke or TIA, we developed and validated a model to predict the presence of OSA (i.e., Apnea-Hypopnea Index ≥5 events per hour). Model performance was compared with that of the Berlin Questionnaire, Epworth Sleepiness Scale (ESS), the Snoring, Tiredness, Observed apnea, high blood Pressure, Body mass index, Age, Neck circumference, and Gender instrument, and the Sleep Apnea Clinical Score. RESULTS: The new SLEEP Inventory (Sex, Left heart failure, ESS, Enlarged neck, weight [in Pounds], Insulin resistance/diabetes, and National Institutes of Health Stroke Scale) performed modestly better than other instruments in identifying patients with OSA, showing reasonable discrimination in the development (c-statistic .732) and validation (c-statistic .731) study populations, and having the highest negative predictive value of all in struments. CONCLUSIONS: Clinicians should be aware of these limitations in OSA screening instruments when making decisions about referral for PSG. The high negative predictive value of the SLEEP INventory may be useful in determining and prioritizing patients with stroke or TIA least in need of overnight PSG.
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    In-hospital outcomes and 30-day readmission rates among ischemic and hemorrhagic stroke patients with delirium
    (PLOS, 2019-11-14) Vahidy, Farhaan S.; Bambhroliya, Arvind B.; Meeks, Jennifer R.; Rahman, Omar; Ely, E. Wesley; Slooter, Arjen J. C.; Tyson, Jon E.; Miller, Charles C.; McCullough, Louise D.; Savitz, Sean I.; Khan, Babar; Medicine, School of Medicine
    OBJECTIVE: Delirium is associated with poor outcomes among critically ill patients. However, it is not well characterized among patients with ischemic or hemorrhagic stroke (IS and HS). We provide the population-level frequency of in-hospital delirium and assess its association with in-hospital outcomes and with 30-day readmission among IS and HS patients. METHODS: We analyzed Nationwide in-hospital and readmission data for years 2010-2015 and identified stroke patients using ICD-9 codes. Delirium was identified using validated algorithms. Outcomes were in-hospital mortality, length of stay, unfavorable discharge disposition, and 30-day readmission. We used survey design logistic regression methods to provide national estimates of proportions and 95% confidence intervals (CI) for delirium, and odds ratios (OR) for association between delirium and poor outcomes. RESULTS: We identified 3,107,437 stroke discharges of whom 7.45% were coded to have delirium. This proportion significantly increased between 2010 (6.3%) and 2015 (8.7%) (aOR, 95% CI: 1.04, 1.03-1.05). Delirium proportion was higher among HS patients (ICH: 10.0%, SAH: 9.8%) as compared to IS patients (7.0%). Delirious stroke patients had higher in-hospital mortality (12.3% vs. 7.8%), longer in-hospital stay (11.6 days vs. 7.3 days) and a significantly greater adjusted risk of 30-day-readmission (16.7%) as compared to those without delirium (12.2%) (aRR, 95% CI: 1.13, 1.11-1.15). Upon readmission, patients with delirium at initial admission continued to have a longer length of stay (7.7 days vs. 6.6 days) and a higher in-hospital mortality (9.3% vs. 6.4%). CONCLUSION: Delirium identified through claims data in stroke patients is independently associated with poor in-hospital outcomes both at index admission and readmission. Identification and management of delirium among stroke patients provides an opportunity to improve outcomes.
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    Interferon-b Modulates Inflammatory Response in Cerebral Ischemia
    (American Heart Association, 2016-01-08) Kuo, Ping-Chang; Scofield, Barbara A.; Yu, I-Chen; Chang, Fen-Lei; Ganea, Doina; Yen, Jui-Hung; Department of Microbiology & Immunology, IU School of Medicine
    BACKGROUND: Stroke is a leading cause of death in the world. In >80% of strokes, the initial acute phase of ischemic injury is due to the occlusion of a blood vessel resulting in severe focal hypoperfusion, excitotoxicity, and oxidative damage. Interferon-β (IFNβ), a cytokine with immunomodulatory properties, was approved by the US Food and Drug Administration for the treatment of relapsing-remitting multiple sclerosis for more than a decade. Its anti-inflammatory properties and well-characterized safety profile suggest that IFNβ has therapeutic potential for the treatment of ischemic stroke. METHODS AND RESULTS: We investigated the therapeutic effect of IFNβ in the mouse model of transient middle cerebral artery occlusion/reperfusion. We found that IFNβ not only reduced infarct size in ischemic brains but also lessened neurological deficits in ischemic stroke animals. Further, multiple molecular mechanisms by which IFNβ modulates ischemic brain inflammation were identified. IFNβ reduced central nervous system infiltration of monocytes/macrophages, neutrophils, CD4(+) T cells, and γδ T cells; inhibited the production of inflammatory mediators; suppressed the expression of adhesion molecules on brain endothelial cells; and repressed microglia activation in the ischemic brain. CONCLUSIONS: Our results demonstrate that IFNβ exerts a protective effect against ischemic stroke through its anti-inflammatory properties and suggest that IFNβ is a potential therapeutic agent, targeting the reperfusion damage subsequent to the treatment with tissue plasminogen activator.
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    Nanotransfection-based vasculogenic cell reprogramming drives functional recovery in a mouse model of ischemic stroke
    (American Association for the Advancement of Science, 2021-03-19) Lemmerman, Luke R.; Balch, Maria H.H.; Moore, Jordan T.; Alzate-Correa, Diego; Rincon-Benavides, Maria A.; Salazar-Puerta, Ana; Gnyawali, Surya; Harris, Hallie N.; Lawrence, William; Ortega-Pineda, Lilibeth; Wilch, Lauren; Risser, Ian B.; Maxwell, Aidan J.; Duarte-Sanmiguel, Silvia; Dodd, Daniel; Guio-Vega, Gina P.; McTigue, Dana M.; Arnold, W. David; Nimjee, Shahid M.; Sen, Chandan K.; Khanna, Savita; Rink, Cameron; Higuita-Castro, Natalia; Gallego-Perez, Daniel; Surgery, School of Medicine
    Ischemic stroke causes vascular and neuronal tissue deficiencies that could lead to substantial functional impairment and/or death. Although progenitor-based vasculogenic cell therapies have shown promise as a potential rescue strategy following ischemic stroke, current approaches face major hurdles. Here, we used fibroblasts nanotransfected with Etv2, Foxc2, and Fli1 (EFF) to drive reprogramming-based vasculogenesis, intracranially, as a potential therapy for ischemic stroke. Perfusion analyses suggest that intracranial delivery of EFF-nanotransfected fibroblasts led to a dose-dependent increase in perfusion 14 days after injection. MRI and behavioral tests revealed ~70% infarct resolution and up to ~90% motor recovery for mice treated with EFF-nanotransfected fibroblasts. Immunohistological analysis confirmed increases in vascularity and neuronal cellularity, as well as reduced glial scar formation in response to treatment with EFF-nanotransfected fibroblasts. Together, our results suggest that vasculogenic cell therapies based on nanotransfection-driven (i.e., nonviral) cellular reprogramming represent a promising strategy for the treatment of ischemic stroke.
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    Serum mercury concentration and the risk of ischemic stroke: The REasons for Geographic and Racial Differences in Stroke Trace Element Study
    (Elsevier, 2018-08) Chen, Cheng; Xun, Pengcheng; McClure, Leslie A.; Brockman, John; MacDonald, Leslie; Cushman, Mary; Cai, Jianwen; Kamendulis, Lisa; Mackey, Jason; He, Ka; Neurology, School of Medicine
    BACKGROUND: Although biologically plausible, epidemiological evidence linking exposure to methylmercury with increased risk of ischemic stroke is limited. The effects of methylmercury may be modified by selenium, which is an anti-oxidant that often co-exists with mercury in fish. OBJECTIVES: To examine the association between serum mercury levels with the incidence of ischemic stroke and to explore the possible effect modifications by serum selenium levels and demographic and geographic factors. METHODS: A case-cohort study was designed nested in the REasons for Geographic and Racial Differences in Stroke cohort, including 662 adjudicated incident cases of ischemic stroke and 2494 participants in a randomly selected sub-cohort. Serum mercury was measured using samples collected at recruitment. Multivariable-adjusted hazard ratios (HRs) and the corresponding 95% confidence intervals (CIs) were estimated using the Barlow-weighting method for the Cox proportional hazards regression model. RESULTS: No statistically significant association was observed between serum mercury concentration and the incidence of ischemic stroke (the highest vs. lowest quintile of mercury levels: HR = 0.82; 95% CI = 0.55-1.22; P for linear trend = 0.42). Sex (P for interaction = 0.06), but not serum selenium levels, modified the association; a more evident trend toward lower incidence of ischemic stroke with higher mercury levels was observed among women. CONCLUSION: This study does not support an association between mercury and the incidence of ischemic stroke within a population with low-to-moderate level of exposure. Further studies are needed to explore the possibility of mercury-induced ischemic stroke toxicity in other populations at higher exposure levels.
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    Temporal Trends in Stroke Incidence over Time by Sex and Age in the Greater Cincinnati Northern Kentucky Stroke Study
    (American Heart Association, 2020-04) Madsen, Tracy E.; Khoury, Jane C.; Leppert, Michelle; Alwell, Kathleen; Moomaw, Charles J.; Sucharew, Heidi; Woo, Daniel; Ferioli, Simona; Martini, Sharyl; Adeoye, Opeolu; Khatri, Pooja; Flaherty, Matthew; De Los Rios La Rosa, Felipe; Mackey, Jason; Mistry, Eva; Demel, Stacie L.; Coleman, Elisheva; Jasne, Adam; Slavin, Sabreena J.; Walsh, Kyle; Star, Michael; Broderick, Joseph P.; Kissela, Brett M.; Kleindorfer, Dawn O.; Neurology, School of Medicine
    Background and Purpose- Sex differences in stroke incidence over time were previously reported from the GCNKSS (Greater Cincinnati/Northern Kentucky Stroke Study). We aimed to determine whether these differences continued through 2015 and whether they were driven by particular age groups. Methods- Within the GCNKSS population of 1.3 million, incident (first ever) strokes among residents ≥20 years of age were ascertained at all local hospitals during 5 periods: July 1993 to June 1994 and calendar years 1999, 2005, 2010, and 2015. Out-of-hospital cases were sampled. Sex-specific incidence rates per 100 000 were adjusted for age and race and standardized to the 2010 US Census. Trends over time by sex were compared (overall and age stratified). Sex-specific case fatality rates were also reported. Bonferroni corrections were applied for multiple comparisons. Results- Over the 5 study periods, there were 9733 incident strokes (56.3% women). For women, there were 229 (95% CI, 215-242) per 100 000 incident strokes in 1993/1994 and 174 (95% CI, 163-185) in 2015 (P<0.05), compared with 282 (95% CI, 263-301) in 1993/1994 to 211 (95% CI, 198-225) in 2015 (P<0.05) in men. Incidence rates decreased between the first and last study periods in both sexes for IS but not for intracerebral hemorrhage or subarachnoid hemorrhage. Significant decreases in stroke incidence occurred between the first and last study periods for both sexes in the 65- to 84-year age group and men only in the ≥85-year age group; stroke incidence increased for men only in the 20- to 44-year age group. Conclusions- Overall stroke incidence decreased from the early 1990s to 2015 for both sexes. Future studies should continue close surveillance of sex differences in the 20- to 44-year and ≥85-year age groups, and future stroke prevention strategies should target strokes in the young- and middle-age groups, as well as intracerebral hemorrhage.