Medicine (RMH) - Research Publications

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    Classification of Different Degrees of Disability Following Intracerebral Hemorrhage: A Decision Tree Analysis from VISTA-ICH Collaboration.
    Phan, TG ; Chen, J ; Beare, R ; Ma, H ; Clissold, B ; Van Ly, J ; Srikanth, V ; VISTA-ICH Collaboration, (Frontiers Media SA, 2017)
    BACKGROUND AND PURPOSE: Prognostication following intracerebral hemorrhage (ICH) has focused on poor outcome at the expense of lumping together mild and moderate disability. We aimed to develop a novel approach at classifying a range of disability following ICH. METHODS: The Virtual International Stroke Trial Archive collaboration database was searched for patients with ICH and known volume of ICH on baseline CT scans. Disability was partitioned into mild [modified Rankin Scale (mRS) at 90 days of 0-2], moderate (mRS = 3-4), and severe disabilities (mRS = 5-6). We used binary and trichotomy decision tree methodology. The data were randomly divided into training (2/3 of data) and validation (1/3 data) datasets. The area under the receiver operating characteristic curve (AUC) was used to calculate the accuracy of the decision tree model. RESULTS: We identified 957 patients, age 65.9 ± 12.3 years, 63.7% males, and ICH volume 22.6 ± 22.1 ml. The binary tree showed that lower ICH volume (<13.7 ml), age (<66.5 years), serum glucose (<8.95 mmol/l), and systolic blood pressure (<170 mm Hg) discriminate between mild versus moderate-to-severe disabilities with AUC of 0.79 (95% CI 0.73-0.85). Large ICH volume (>27.9 ml), older age (>69.5 years), and low Glasgow Coma Scale (<15) classify severe disability with AUC of 0.80 (95% CI 0.75-0.86). The trichotomy tree showed that ICH volume, age, and serum glucose can separate mild, moderate, and severe disability groups with AUC 0.79 (95% CI 0.71-0.87). CONCLUSION: Both the binary and trichotomy methods provide equivalent discrimination of disability outcome after ICH. The trichotomy method can classify three categories at once, whereas this action was not possible with the binary method. The trichotomy method may be of use to clinicians and trialists for classifying a range of disability in ICH.
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    Cerebral small vessel disease, medial temporal lobe atrophy and cognitive status in patients with ischaemic stroke and transient ischaemic attack
    Arba, F ; Quinn, T ; Hankey, GJ ; Ali, M ; Lees, KR ; Inzitari, D (WILEY, 2017-02)
    BACKGROUND AND PURPOSE: Small vessel disease (SVD) and Alzheimer's disease (AD) are two common causes of cognitive impairment and dementia, traditionally considered as distinct processes. The relationship between radiological features suggestive of AD and SVD was explored, and the association of each of these features with cognitive status at 1 year was investigated in patients with stroke or transient ischaemic attack. METHODS: Anonymized data were accessed from the Virtual International Stroke Trials Archive (VISTA). Medial temporal lobe atrophy (MTA; a marker of AD) and markers of SVD were rated using validated ordinal visual scales. Cognitive status was evaluated with the Mini Mental State Examination (MMSE) 1 year after the index stroke. Logistic regression models were used to investigate independent associations between (i) baseline SVD features and MTA and (ii) all baseline neuroimaging features and cognitive status 1 year post-stroke. RESULTS: In all, 234 patients were included, mean (±SD) age 65.7 ± 13.1 years, 145 (62%) male. Moderate to severe MTA was present in 104 (44%) patients. SVD features were independently associated with MTA (P < 0.001). After adjusting for age, sex, disability after stroke, hypertension and diabetes mellitus, MTA was the only radiological feature independently associated with cognitive impairment, defined using thresholds of MMSE ≤ 26 (odds ratio 1.94; 95% confidence interval 1.28-2.94) and MMSE ≤ 23 (odds ratio 2.31; 95% confidence interval 1.48-3.62). CONCLUSION: In patients with ischaemic cerebrovascular disease, SVD features are associated with MTA, which is a common finding in stroke survivors. SVD and AD type neurodegeneration coexist, but the AD marker MTA, rather than SVD markers, is associated with post-stroke cognitive impairment.
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    Audit of CT reporting standards in cases of intracerebral haemorrhage at a comprehensive stroke centre in Australia
    Barras, CD ; Asadi, H ; Phal, PM ; Tress, BM ; Davis, SM ; Desmond, PM (WILEY-BLACKWELL, 2016-12)
    INTRODUCTION: Multiple CT-derived biomarkers that are predictive of intracerebral haemorrhage (ICH) growth and outcome have been described in the literature, but the extent to which these appear in imaging reports of ICH is unknown. The aim of this retrospective process audit was to determine which of the known predictors of ICH outcome was recorded in reports of the disease, with a view to providing reporting recommendations, as appropriate. METHOD: We examined the initial CT report of patients diagnosed with ICH presenting to a metropolitan comprehensive stroke centre and meeting inclusion criteria during the audit period between 1 March 2013 and 28 February 2014. Each report was assessed for the inclusion of the following ICH characteristics: the number of measurement dimensions; volume; location; hydrocephalus; shape; density; 'CTA spot sign' (where CTA was performed). RESULTS: A total of 100 patients met audit inclusion criteria. At least one ICH dimension was recorded in 90% of reports; however, 39% did not include the measurements in three dimensions and volume was reported in just 6%. No ICH dimension was recorded in 10% of reports. With the exception of density and shape, reporting of other CT features exceeded 95%. Where CTA was performed (58%), 14 (24%) of 58 reported the 'CTA spot sign' status. CONCLUSION: In this audit, volume was the most under-reported of the established ICH characteristics predictive of ICH outcome. Readily calculated from multiplanar reformats using the ABC/2 technique, the routine reporting of ICH volume is recommended. More reporting attention to ICH density heterogeneity and shape irregularity is encouraged, given their emerging importance. Where acute CTA is performed, the presence of any dynamic haemorrhage (CTA spot sign) should be reported.
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    Impact of heart rate on admission on mortality and morbidity in acute ischaemic stroke patients - results from VISTA
    Nolte, CH ; Erdur, H ; Grittner, U ; Schneider, A ; Piper, SK ; Scheitz, JF ; Wellwood, I ; Bath, PMW ; Diener, H-C ; Lees, KR ; Endres, M (WILEY-BLACKWELL, 2016-12)
    BACKGROUND AND PURPOSE: Elevated heart rate (HR) is associated with worse outcomes in patients with cardiovascular disease. Its predictive value in acute stroke patients is less well established. We investigated the effects of HR on admission in acute ischaemic stroke patients. METHODS: Using the Virtual International Stroke Trials Archive (VISTA) database, the association between HR in acute stroke patients without atrial fibrillation and the pre-defined composite end-point of (recurrent) ischaemic stroke, transient ischaemic attack (TIA), myocardial infarction (MI) and vascular death within 90 days was analysed. Pre-defined secondary outcomes were the composite end-point components and any death, decompensated heart failure and degree of functional dependence according to the modified Rankin Scale after 90 days. HR was analysed as a categorical variable (quartiles). RESULTS: In all, 5606 patients were available for analysis (mean National Institutes of Health Stroke Scale 13; mean age 67 years; mean HR 77 bpm; 44% female) amongst whom the composite end-point occurred in 620 patients (11.1%). Higher HR was not associated with the composite end-point. The frequencies of secondary outcomes were 3.2% recurrent stroke (n = 179), 0.6% TIA (n = 35), 1.8% MI (n = 100), 6.8% vascular death (n = 384), 15.0% any death (n = 841) and 2.2% decompensated heart failure (n = 124). Patients in the highest quartile (HR> 86 bpm) were at increased risk for any death [adjusted hazard ratio (95% confidence interval) 1.40 (1.11-1.75)], decompensated heart failure [adjusted hazard ratio 2.20 (1.11-4.37)] and worse modified Rankin Scale [adjusted odds ratio 1.29 (1.14-1.52)]. CONCLUSIONS: In acute stroke patients, higher HR (>86 bpm) is linked to mortality, heart failure and higher degree of dependence after 90 days but not to recurrent stroke, TIA or MI.
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    Longitudinal Ultrasound Curriculum Incorporation at West Virginia University School of Medicine: A Description and Graduating Students' Perceptions.
    Minardi, J ; Ressetar, H ; Foreman, T ; Craig, K ; Sharon, M ; Bassler, J ; Davis, S ; Machi, A ; Cottrell, S ; Denne, N ; Ferrari, N ; Landreth, K ; Palmer, B ; Schaefer, G ; Tallaksen, R ; Wilks, D ; Williams, D (Wiley, 2019-01)
    OBJECTIVES: Sonography is a clinical tool being incorporated in multiple medical specialties with evidence of improved patient care and cost. Some schools have begun implementing ultrasound curricula. We hope to build upon that foundation and provide another potential framework of incorporation. There are several barriers, including curricular space, equipment and physical space, adequate faculty, and performing assessment. METHODS: At West Virginia University, we began a longitudinal ultrasound curriculum in 2012 with incorporation of didactic and practical sessions into gross anatomy, our systems-based second-year curriculum, physical diagnosis course, and clinical rotations. We included both written and practical assessment from the onset. After the initial 4 years, the first graduates were surveyed on their perceptions of the curriculum. Responses were correlated with specialty choice and clinical campus site. RESULTS: Based on our survey (90% response rate), students felt sonography was useful for anatomical understanding and patient care. Overall, 93% of our respondents reviewed the curriculum favorably. Qualitative feedback was very positive, with students desiring more ultrasound education and more required components, specifically in clinical rotations. CONCLUSIONS: Based on these results, some changes have already been implemented, including decreased student-to-instructor ratios, more open scan time, and more required components. The breadth of formal assessment has increased. Multiple pilot programs for clinical rotations are being developed. There is an ongoing need for faculty development and continued assessment of ultrasound competency.
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    White Matter Degeneration after Ischemic Stroke: A Longitudinal Diffusion Tensor Imaging Study
    Visser, MM ; Yassi, N ; Campbell, BCV ; Desmond, PM ; Davis, SM ; Spratt, N ; Parsons, M ; Bivard, A (WILEY, 2019-01)
    BACKGROUND AND PURPOSE: Degeneration of gray matter and subcortical structures after ischemic stroke has been well described. However, little is known about white matter degeneration after stroke. It is unclear whether white matter degeneration occurs throughout the whole brain, or whether patterns of degeneration occur more in specific brain areas. METHODS: We prospectively collected National Institutes of Health Stroke Scale (NIHSS) scores and diffusion tensor imaging (DTI) in patients with acute ischemic stroke within the first week after onset (baseline), and at 1 and 3 months. DTI was processed to produce maps of fractional anisotropy, apparent diffusion coefficients, and axial and radial diffusivity. DTI parameters in specified regions-of-interest corresponding to items on the NIHSS were calculated and changes over time were assessed using linear mixed-effect modeling. RESULTS: Seventeen patients were included in the study. Mean age (SD) was 71 (11.7) years, and median (IQR) baseline NIHSS 9 (5-13.3). Changes over time were observed in both visual cortices, contralesional primary motor cortex, premotor cortex, and superior temporal gyrus (P < .05). Changes in the ipsilesional motor cortex and inferior parietal lobule were only seen in patients with scores on the respective NIHSS-items (P < .05). No significant changes in global white matter diffusivity parameters were identified (P > .05). CONCLUSION: White matter changes after stroke may be localized rather than a global phenomenon.
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    Comparative Analysis of Markers of Mass Effect after Ischemic Stroke
    Ostwaldt, A-C ; Battey, TWK ; Irvine, HJ ; Campbell, BCV ; Davis, SM ; Donnan, GA ; Kimberly, WT (WILEY, 2018-09)
    BACKGROUND AND PURPOSE: Midline shift determined on magnetic resonance imaging (MRI) or computed tomography (CT) images is a well-validated marker of mass effect after large hemispheric infarction and associated with mortality. In this study, we targeted a population with moderately sized strokes. We compared midline shift to other imaging markers and determined their ability to predict long-term outcome. METHODS: MRI scans were studied from the Echoplanar Imaging Thrombolysis Evaluation Trial (EPITHET) cohort. Midline shift, acute stroke lesion volume, lesional swelling volume, change in ipsilateral hemisphere volume, the ratio of ipsilateral to contralateral hemisphere volume, and the reduction in lateral ventricle volume were measured. The relationships of these markers with poor outcome (modified Rankin scale score 3-6 at day 90) were assessed. Receiver-operating characteristic (ROC) curves were generated to compare the performance of each metric. RESULTS: Of the 71 included patients, 59.2% had a poor outcome that was associated with significantly larger values for midline shift, lesional swelling volume, and ratio of hemisphere volumes. Lesional swelling volume, change in hemisphere volume, ratio of hemisphere volumes, and lateral ventricle displacement were each correlated with midline shift (Spearman r = .60, .49, .61, and -.56, respectively; all P < .0001). ROC curve analysis showed that lesional swelling volume (area under the curve [AUC] = .791) predicted poor outcome better than midline shift (AUC = .682). For predicting mortality, ROC curve analysis showed that these three markers were equivalent. CONCLUSION: The ratio of ipsilateral to contralateral hemisphere volume, baseline lesion volume and lesional swelling volume best predicted poor outcome across a spectrum of stroke sizes.
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    Exploring Health Insurance Status and Emergency Department Utilization.
    Agarwal, P ; Bias, TK ; Vasile, E ; Moore, L ; Davis, S ; Davidov, D (SAGE Publications, 2015)
    Emergency department (ED) use, by both insured and uninsured, leads to significant health care costs in the United States. While frequent ED use is often attributed to the uninsured, there is some evidence that insured populations also report utilizing the ED when otherwise preventable or nonurgent. We conducted in-person surveys of patients visiting the ED at a large research hospital and examined the differences in their characteristics based on the health insurance status. While less than the uninsured, insured individuals still report barriers to access to care outside the ED that include lack of access to another health care facility and unavailability of a doctor's office or clinic.
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    Introducing Medical Students into the Emergency Department: The Impact upon Patient Satisfaction.
    Kiefer, C ; Turner, JS ; Layman, SM ; Davis, SM ; Besinger, BR ; Humbert, A (Western Journal of Emergency Medicine, 2015-11)
    INTRODUCTION: Performance on patient satisfaction surveys is becoming increasingly important for practicing emergency physicians and the introduction of learners into a new clinical environment may impact such scores. This study aimed to quantify the impact of introducing fourth-year medical students on patient satisfaction in two university-affiliated community emergency departments (EDs). METHODS: Two community-based EDs in the Indiana University Health (IUH) system began hosting medical students in March 2011 and October 2013, respectively. We analyzed responses from patient satisfaction surveys at each site for seven months before and after the introduction of students. Two components of the survey, "Would you recommend this ED to your friends and family?" and "How would you rate this facility overall?" were selected for analysis, as they represent the primary questions reviewed by the Center for Medicare Services (CMS) as part of value-based purchasing. We evaluated the percentage of positive responses for adult, pediatric, and all patients combined. RESULTS: Analysis did not reveal a statistically significant difference in the percentage of positive response for the "would you recommend" question at both clinical sites with regards to the adult and pediatric subgroups, as well as the all-patient group. At one of the sites, there was significant improvement in the percentage of positive response to the "overall rating" question following the introduction of medical students when all patients were analyzed (60.3% to 68.2%, p=0.038). However, there was no statistically significant difference in the "overall rating" when the pediatric or adult subgroups were analyzed at this site and no significant difference was observed in any group at the second site. CONCLUSION: The introduction of medical students in two community-based EDs is not associated with a statistically significant difference in overall patient satisfaction, but was associated with a significant positive effect on the overall rating of the ED at one of the two clinical sites studied. Further study is needed to evaluate the effect of medical student learners upon patient satisfaction in settings outside of a single health system.
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    Needle exchange programs for the prevention of hepatitis C virus infection in people who inject drugs: a systematic review with meta-analysis.
    Davis, SM ; Daily, S ; Kristjansson, AL ; Kelley, GA ; Zullig, K ; Baus, A ; Davidov, D ; Fisher, M (Springer Science and Business Media LLC, 2017-05-17)
    BACKGROUND: Previous research on the effectiveness of needle exchange programs (NEP) in preventing hepatitis C virus (HCV) in people who inject drugs (PWID) has shown mixed findings. The purpose of this study was to use the meta-analytic approach to examine the association between NEP use and HCV prevention in PWIDs. METHODS: Study inclusion criteria were (1) observational studies, (2) PWIDs, (3) NEP use, (4) HCV status ascertained by serological testing, (5) studies published in any language since January 1, 1989, and (6) data available for measures of association. Studies were located by searching four electronic databases and cross-referencing. Study quality was assessed using the Newcastle Ottawa (NOS) scale. A ratio measure of association was calculated for each result from cohort or case-control studies and pooled using a random effects model. Odds ratio (OR) and hazard ratio (HR) models were analyzed separately. Results were considered statistically significant if the 95% confidence interval (CI) did not cross 1. Heterogeneity was estimated using Q and I 2 with alpha values for Q ≤ 0.10 considered statistically significant. RESULTS: Of the 555 citations reviewed, 6 studies containing 2437 participants were included. Studies had an average NOS score of 7 out of 9 (77.8%) stars. Concerns over participant representativeness, unclear adjustments for confounders, and bias from participant nonresponse and loss to follow-up were noted. Results were mixed with the odds ratio model indicating no consistent association (OR, 0.51, 95% CI, 0.05-5.15), and the hazard ratio model indicating a harmful effect (HR, 2.05, 95% CI, 1.39-3.03). Substantial heterogeneity (p ≤ 0.10) and moderate to large inconsistency (I 2  ≥ 66%) were observed for both models. CONCLUSIONS: The impact of NEPs on HCV prevention in PWIDs remains unclear. There is a need for well-designed research studies employing standardized criteria and measurements to clarify this issue. TRIAL REGISTRATION: PROSPERO CRD42016035315.