Browsing by Author "Howard, George"

Now showing 1 - 7 of 7
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    Association of Prediabetes and Diabetes With Stroke Symptoms The REasons for Geographic And Racial Differences in Stroke (REGARDS) Study
    (2012-09) Carson, April P; Muntner, Paul; Kissella, Brett M; Kleindorfer, Dawn O.; Howard, Virginia J; Meschia, James F; Williams, Linda S.; Prineas, Ronald J; Howard, George; Safford, Monika M
    OBJECTIVE Stroke symptoms among individuals reporting no physician diagnosis of stroke are associated with an increased risk of future stroke. Few studies have assessed whether individuals with diabetes or prediabetes, but no physician diagnosis of stroke, have an increased prevalence of stroke symptoms. RESEARCH DESIGN AND METHODS This study included 25,696 individuals aged ≥45 years from the REasons for Geographic And Racial Differences in Stroke (REGARDS) study who reported no history of stroke or transient ischemic attack at baseline (2003–2007). Glucose measurements, medication use, and self-reported physician diagnosis were used to categorize participants into diabetes, prediabetes, or normal glycemia groups. The presence of six stroke symptoms was assessed using a validated questionnaire. RESULTS The prevalence of any stroke symptom was higher among participants with diabetes (22.7%) compared with those with prediabetes (15.6%) or normal glycemia (14.9%). In multivariable models, diabetes was associated with any stroke symptom (prevalence odds ratio [POR] 1.28 [95% CI 1.18–1.39]) and two or more stroke symptoms (1.26 [1.12–1.43]) compared with normal glycemia. In analyses of individual stroke symptoms, diabetes was associated with numbness (1.15 [1.03–1.29]), vision loss (1.52 [1.31–1.76]), half-vision loss (1.54 [1.30–1.84]), and lost ability to understand people (1.34 [1.12–1.61]) after multivariable adjustment. No association was present between prediabetes and stroke symptoms. CONCLUSIONS In this population-based study, almost one in four individuals with diabetes reported stroke symptoms, which suggests that screening for stroke symptoms in diabetes may be warranted.
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    Performance of the NINDS-CSN 5-Minute Protocol in a National Population-Based Sample
    (Cambridge University Press, 2014-09) Kennedy, Richard E.; Wadley, Virginia G.; McClure, Leslie A.; Letter, Abraham J.; Unverzagt, Frederick W.; Crowe, Michael; Nyenhius, David; Kelley, Brendan J.; Kana, Bhumika; Marceaux, Janice; Tamura, Manjula Kurella; Howard, Virginia; Howard, George; Department of Psychiatry, IU School of Medicine
    Background In 2006, the National Institute of Neurological Disorders and Stroke-Canadian Stroke Network (NINDS-CSN) Vascular Cognitive Impairment Harmonization Standards recommended a 5-Minute Protocol as a brief screening instrument for vascular cognitive impairment (VCI). We report demographically adjusted norms for the 5-Minute Protocol and its relation to other measures of cognitive function and cerebrovascular risk factors. Methods Cross-sectional analysis of 7,199 stroke-free adults in the REasons for Geographic And Racial Differences in Stroke (REGARDS) study on the NINDS-CSN 5-Minute Protocol score. Results Total scores on the 5-Minute Protocol were inversely correlated with age and positively correlated with years of education, and performance on the Six-Item Screener, Word List Learning, and Animal Fluency (all p-values<0.001). Higher cerebrovascular risk on the Framingham Stroke Risk Profile (FSRP) was associated with lower total 5-Minute Protocol scores (p<0.001). The 5-Minute Protocol also differentiated between participants with and without confirmed stroke and with and without stroke symptom histories (p<0.001). Conclusions The NINDS-CSN 5-Minute Protocol is a brief, easily administered screening measure that is sensitive to cerebrovascular risk and offers a valid method of screening for cognitive impairment in populations at risk for VCI.
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    Racial differences in recurrent ischemic stroke risk and recurrent stroke case fatality
    (Wolters Kluwer, 2018) Albright, Karen C.; Huang, Lei; Blackburn, Justin; Howard, George; Mullen, Michael; Bittner, Vera; Muntner, Paul; Howard, Virginia; Health Policy and Management, School of Public Health
    Objective: To determine black-white differences in 1-year recurrent stroke and 30-day case fatality after a recurrent stroke in older US adults. Methods: We conducted a retrospective cohort study using a 5% random sample of Medicare beneficiaries with fee-for-service health insurance coverage who were hospitalized for ischemic stroke between 1999 and 2013. Hazard ratios for recurrent ischemic stroke and risk ratios for 30-day case fatality comparing blacks to whites were calculated with adjustment for demographics, risk factors, and competing risk of death when appropriate. Results: Among 128,789 Medicare beneficiaries having an ischemic stroke (mean age 80 years [SD 8 years], 60.4% male), 11.1% were black. The incidence rate of recurrent ischemic stroke per 1,000 person-years for whites and blacks was 108 (95% confidence interval [CI], 106-111) and 154 (95% CI 147-162) , respectively. The multivariable-adjusted hazard ratio for recurrent stroke among blacks compared with whites was 1.36 (95% CI 1.29-1.44). The case fatality after recurrent stroke for blacks and whites was 21% (95% CI 21%-22%) and 16% (95% CI 15%-18%), respectively. The multivariable-adjusted relative risk for mortality within 30 days of a recurrent stroke among blacks compared with whites was 0.82 (95% CI 0.73-0.93). Conclusion: The risk of stroke recurrence among older Americans hospitalized for ischemic stroke is higher for blacks compared to whites, while 30-day case fatality after recurrent stroke remains lower for blacks.
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    Relation of Atrial Fibrillation to Cognitive Decline (from the REasons for Geographic and Racial Differences in Stroke [REGARDS] Study)
    (Elsevier, 2021) Bailey, Margie J.; Soliman, Elsayed Z.; McClure, Leslie A.; Howard, George; Howard, Virginia J.; Judd, Suzanne E.; Unverzagt, Fred; Wadley, Virginia; Sachs, Bonnie C.; Hughes, Timothy M.; Psychiatry, School of Medicine
    The association of atrial fibrillation (AF) with cognitive function remains unclear, especially among racially/geographically diverse populations. This analysis included 25,980 black and white adults, aged 48+, from the national REasons for Geographic and Racial Differences in Stroke (REGARDS) cohort, free from cognitive impairment and stroke at baseline. Baseline AF was identified by self-reported medical history or electrocardiogram (ECG). Cognitive testing was conducted yearly with the Six Item Screener (SIS) to define impairment and at 2-year intervals to assess decline on: animal naming and letter fluency, Montreal Cognitive Assessment (MoCA), Word List Learning (WLL) and Delayed Recall tasks (WLD). Multivariable regression models estimated the relationships between AF and baseline impairment and time to cognitive impairment. Models were adjusted sequentially for age, sex, race, geographic region, and education, then cardiovascular risk factors and finally incident stroke. AF was present in 2,168 (8.3%) participants at baseline. AF was associated with poorer baseline performance on measures of: semantic fluency (p<0.01); global cognitive performance (MoCA, p<0.01); and WLD (p<0.01). During a mean follow-up of 8.06 years, steeper declines in list learning were observed among participants with AF (p<0.03) which remained significant after adjusting for cardiovascular risk factors (p<0.04) and incident stroke (p<0.03). Effect modification by race, sex and incident stroke on AF and cognitive decline were also detected. In conclusion, AF was associated with poorer baseline cognitive performance across multiple domains and incident cognitive impairment in this bi-racial cohort. Additional adjustment for cardiovascular risk factors attenuated these relations with the exception of learning.
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    Risk Factors for Poststroke Cognitive Decline: The REGARDS Study (Reasons for Geographic and Racial Differences in Stroke)
    (American Heart Association, 2018-04) Levine, Deborah A.; Wadley, Virginia G.; Langa, Kenneth M.; Unverzagt, Frederick W.; Kabeto, Mohammed U.; Giordani, Bruno; Howard, George; Howard, Virginia J.; Cushman, Mary; Judd, Suzanne; Galecki, Andrzej T.; Psychiatry, School of Medicine
    Background and Purpose Poststroke cognitive decline (PSCD) causes disability. Risk factors for PSCD independent of survivors’ prestroke cognitive trajectories are uncertain. Methods Among 22,875 participants age ≥45 without baseline cognitive impairment from the Reasons for Geographic and Racial Differences in Stroke (REGARDS) cohort, enrolled 2003–2007 and followed through September 2015, we measured the effect of incident stroke (n=694) on changes in cognitive functions and cognitive impairment (Six-Item Screener score <5) and tested whether patient factors modified the effect. Median follow-up was 8.2 years. Results Incident stroke was associated with acute declines in global cognition, new learning, verbal memory, and executive function. Acute declines in global cognition after stroke were greater in survivors who were black (P=0.04), male (P=0.04), had cardioembolic (P=0.001) or large artery stroke (P=0.001). Acute declines in executive function after stroke were greater in survivors who had
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    Vascular-brain Injury Progression after Stroke (VIPS) Study: concept for understanding racial and geographic determinants of cognitive decline after stroke
    (Elsevier, 2020) Sarfo, Fred Stephen; Akinyemi, Rufus; Howard, George; Howard, Virginia J.; Wahab, Kolawole; Cushman, Mary; Levine, Deborah A.; Ogunniyi, Adesola; Unverzagt, Fred; Owolabi, Mayowa; Ovbiagele, Bruce; Psychiatry, School of Medicine
    Cognitive impairment and dementia (CID) are major public health problems with substantial personal, social, and financial burdens. African Americans are at a heightened risk for Vascular Cognitive Impairment (VCI) compared to European Americans. Recent lines of evidence also suggest a high burden of Post-stroke VCI among indigenous Africans. A better understanding of the cause(s) of the racial disparity in CID, specifically VCI, is needed in order to develop strategies to reduce it. We propose and discuss the conceptual framework for a unique tri-population, trans-continental study titled The Vascular brain Injury Progression after Stroke (VIPS) study. The overarching objective of the VIPS Study will be to explore the interplay of multiple factors (racial, geographical, vascular, lifestyle, nutritional, psychosocial and inflammatory) influencing the level and trajectory of post-stroke cognitive outcomes and examine whether differences between indigenous Africans, African Americans and European Americans exist. We hypothesize that differences which might be due to racial factors will be observed in African Americans versus European Americans as well as Indigenous Africans versus European Americans but not in African Americans versus Indigenous Americans; differences due to geographical factors will be observed in Indigenous Americans versus African Americans and Indigenous Africans versus European Americans but not in African Americans versus European Americans. This overarching objective could be accomplished by building upon existing National Institutes of Health investments in the REasons for Geographical And Racial Differences in Stroke (REGARDS) study (based in the United States of America) and the Stroke Investigative Research and educational Network (SIREN) study (based in Sub-Saharan Africa).
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    Verbal Fluency in a National Sample: Telephone Administration Methods
    (Wiley, 2019-01-18) Marceaux, Janice C.; Prosje, Michelle A.; McClure, Leslie A.; Kana, Bhumika; Crowe, Michael; Kissela, Brett; Manly, Jennifer; Howard, George; Tam, Joyce W.; Unverzagt, Frederick W.; Wadley, Virginia G.; Psychiatry, School of Medicine
    Objectives: Describe novel methods for ascertaining verbal fluency in a large national sample of adults, examine demographic factors influencing performance, and compare scores to studies using in-person assessment. Methods/Design: Participants were from the REasons for Geographic and Racial Differences in Stroke (REGARDS) study, a national, population-based, longitudinal study of stroke in adults aged 45 years an older. Letter and semantic fluency were gathered, using Letter “F” and Animal Naming, via a telephone-based assessment with computer-assisted scoring of digital recordings. Results: Initial letter and semantic fluency scores were obtained on 18,505 and 18,072 participants, respectively. For both fluency tests, scores were normally distributed. Younger age and more years of education were associated with better performances (p<0.0001). The mean and standard deviation for matched subgroups, based on age, gender, and education, were quite comparable to scores reported out of samples using an in-person administration format. Telephone-based assessment also allowed for a level of quality control not available via in-person measurement. Conclusions: Telephone-based assessment of verbal fluency and computer-assisted scoring programs designed for this study facilitated large scale data acquisition, storage, and scoring of protocols. The resulting scores have similar characteristics to those obtained by traditional methods. These findings extend validation of cognitive assessment methods, using survey research staff and computer-assisted technology for test administration.