Leonid Churilov

The Florey Institute of Neuroscience and Mental Health, Melbourne, Victoria, Australia

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Publications (147)303.73 Total impact

  • International Journal of Stroke 01/2015; 10(1). · 4.03 Impact Factor
  • Cerebrovascular diseases (Basel, Switzerland). 11/2014; 38(5):393-394.
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    ABSTRACT: Background Large vessel occlusion (LVO) is associated with poor functional outcome in acute ischemic stroke. Given the uncertainty whether LVO has the same significance in mild and severe stroke, we compared functional outcomes after intravenous thrombolysis, based on severity and LVO. Methods Ischemic stroke patients were thrombolyzed in less than 4.5 hours after onset between 2007 and 2013. LVO was defined as occlusion of one of the following arteries: internal carotid, middle cerebral (M1/M2), anterior cerebral (A1), posterior cerebral (P1), basilar, or vertebral (V4) arteries on prethrombolysis computed tomography angiography. Mild stroke was defined as baseline National Institutes of Health Stroke Scale (NIHSS) score 0-6. Favorable outcome was defined as modified Rankin Scale (mRS) score 0-1 at 3 months or equal to the prestroke mRS. Results There were 175 acute stroke patients, median age 74 years (interquartile range [IQR], 64-83), median baseline NIHSS = 11 (IQR, 5-16), and 63 of 175 patients (36%) with mild stroke. LVO was associated with worse outcome in severe stroke (age-adjusted odds ratio [OR] of favorable outcome, .42; 95% confidence interval [CI], .19-.93; P = .033) and mortality (age-adjusted OR, 3.52; 95% CI, 1.08-11.48; P = .037). Although the difference in favorable outcome between mild stroke patients with and without LVO was not significant (55.6% vs. 74.1%, P = .262; age-adjusted OR of favorable outcome, .42; 95% CI, .1-1.84; P = .251), the similarity of effects across both subgroups cannot be excluded (LVO-by-stroke severity interaction test, P = .906). Conclusions LVO is associated with worse functional outcome and mortality in severe stroke after intravenous thrombolysis. Although significant association between LVO and outcome in mild stroke was not found, there were similar effects on outcome and a larger study might well confirm a relationship.
    Journal of Stroke and Cerebrovascular Diseases. 11/2014;
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    ABSTRACT: Advanced imaging may refine patient selection for ischemic stroke treatment but delays to acquire and process the imaging have limited implementation.
    International Journal of Stroke 10/2014; · 4.03 Impact Factor
  • Yuan Gao, Leonid Churilov, Sarah Teo, Bernard Yan
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    ABSTRACT: Remote intracerebral haemorrhage (rICH) is defined as intracerebral haemorrhage (ICH) post thrombolysis in brain regions without visible ischaemic changes. There is uncertainty that clinical outcomes and risk factors for rICH are different to those for local ICH. We investigated the morbidity, mortality and factors associated with rICH. We hypothesised that a previous history of cerebral ischaemic events is associated with increased risk of rICH. We included consecutive acute ischaemic stroke patients from 2003 to 2012 who were treated with intravenous thrombolysis. Clinical data included demographics, stroke classification, vascular risk factors and laboratory results. Clinical outcome was defined by modified Rankin Scale (mRS) score at 3 months. Baseline and follow-up CT scans were analysed for all ICH, and further dichotomised to rICH and local ICH. Clinical outcomes between rICH and local ICH were compared after adjustment for confounding factors. Four hundred and two patients were included in the study. The median age was 71 (interquartile range 60–79) years, and 54% were male. ICH (local ICH and rICH) was detected in 21.6% (87/402) of all patients post thrombolysis. The incidence of rICH was 2.2% (9/402). Most rICH were classified as haemorrhagic infarct category 2 (HI2) (p = 0.002). The proportion of patients with previous transient ischaemic attacks was significantly higher in the rICH group (33.33% versus 2.56%; odds ratio [OR] 18.75, 95% confidence interval [CI] 3.06–114.38; p = 0.007). The proportion of mRS scores 0–2 at 3 months was significantly higher in the rICH group (50% versus 28%; adjusted OR 10.469, 95%CI 1.474–74.338; p = 0.019). The 3 month mortality rate was 22.2% (2/9) in the rICH group and 36% (27/75) in the local ICH group (OR 0.53, 95%CI 0–2.51, p = 0.703). rICH was an infrequent complication after intravenous thrombolysis in our series. The clinical outcome of rICH was significantly better than local ICH. Of note, previous episodes of transient ischaemic attack were significantly higher in the rICH group, suggesting previous ischaemic injury as an underlying mechanism.
    Journal of Clinical Neuroscience. 10/2014;
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    ABSTRACT: Background: Early decompressive hemicraniectomy following malignant middle cerebral artery (MCA) infarction reduces mortality and improves clinical outcome. Imaging predictors of malignant infarction may serve as 'red flags', prompting intensive neurological monitoring and timely intervention. Our objective is to investigate whether lower ASPECTS (Alberta Stroke Program Early CT Score) is associated with malignant MCA infarction. Methods: A retrospective cohort study of all patients with MCA territory ischemic strokes who were admitted to the Royal Melbourne Hospital (RMH) between 1 January 2009 and 31 December 2009 (226 patients included). The main outcome measures were ASPECTS on admission for each patient and the development of malignant MCA infarction. Results: One-hundred-and-eight patients out of 226 (48%) developed malignant MCA infarction. Good (>0.8) inter-rater agreement between observers scoring ASPECTS was observed using weighted kappa, intra-class correlation coefficient and Lin's concordance coefficients. Using receiver operating characteristic (ROC) curve analysis, we validated that ASPECTS 7 was the optimal cut-off score to determine progression to malignant infarction, providing 50% sensitivity and 86% specificity. One hundred and fifty six patients had ASPECTS >7 (69%) and 70 patients had ASPECTS ≤7 (31%). Patients with ASPECTS ≤7 were significantly younger than those with ASPECTS >7, with the median age of each group being 72.5 and 78 respectively (p = 0.02); otherwise the groups were well-matched. With ASPECTS ≤7, 54 out of 70 patients (77%) developed malignant MCA infarction, compared with 54 out of 156 patients (35%) with ASPECTS >7 (age-adjusted OR = 0.12, 95% CI: 0.06, 0.25; p < 0.0001). If ASPECTS ≤7 is a positive result, then the positive predictive value is 77% and the negative predictive value is 65%. The median ASPECTS for developing malignant MCA infarction was 7.5 (IQR: 5 to 10), while the median ASPECTS for not developing MCA infarction was 10 (IQR: 8 to 10), resulting in a significant age-adjusted median difference of 2 (95% CI: 0.8, 3.2; p < 0.0001). We also found that coma on admission is associated with the development of malignant MCA infarction (OR = 22.63, 95% CI: 1.3, 393.7; p = 0.0323) and that a history of hypertension is not associated with the development of malignant MCA infarction (OR = 0.9707, 95% CI: 0.54, 1.75; p = 0.9213). Conclusions: ASPECTS ≤7 on initial brain CT in a patient with MCA infarction is associated with the development of malignant MCA infarction. We recommend close monitoring of, and early consideration of decompressive hemicraniectomy for, acute stroke patients with ASPECTS ≤7. © 2014 S. Karger AG, Basel.
    Cerebrovascular diseases (Basel, Switzerland). 09/2014; 38(1):39-45.
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    ABSTRACT: BackgroundA key treatment for acute ischaemic stroke is thrombolysis (rtPA). However, treatment is not devoid of side effects and patients are carefully selected. AVERT (A Very Early Rehabilitation Trial), a large, ongoing international phase III trial, tests whether starting out of bed activity within 24 hours of stroke onset improves outcome. Patients treated with rtPA can be recruited if the physician allows (447 included to date). This study aimed to identify factors that might influence the inclusion of rtPA treated patients in AVERT.Methods Data from all patients thrombolysed at Austin Health, Australia, between September 2007 and December 2011 were retrospectively extracted from medical records. Factors of interest included: demographic and stroke characteristics, 24 hour clinical response to rtPA treatment, cerebral imaging and process factors (day and time of admission).Results211 patients received rtPA at Austin Health and 50 (24%) were recruited to AVERT (AVERT). Of the 161 patients not recruited, 105 (65%) were eligible, and could potentially have been included (pot-AVERT). There were no significant differences in demographics, Oxfordshire classification or stroke severity (NIHSS) on admission between groups. Size and localization of stroke on imaging and symptomatic intracerebral heamorrhage rate did not differ. Patients included in AVERT showed less change in NIHSS 24 hours post rtPA (median change = 1, IQR (¿1,4)) than those in the pot-AVERT group (median change = 3, IQR (0,6)) by the median difference of 2 points (95%CI:0.3; p = 0.03). A higher proportion of rtPA treated AVERT patients were admitted on weekdays (p = 0.04).Conclusion Excluding a possible clinical instability, no significant clinical differences were identified between thrombolysed patients included in AVERT and those who were not. Over 500 AVERT patients will be treated with rtPA at trial end. These results suggest we may be able to generalize findings to other rtPA treated patients beyond the trial population.
    BMC Neurology 08/2014; 14(1):163. · 2.56 Impact Factor
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    ABSTRACT: Early neurological recovery after intravenous thrombolysis (IVT) is associated with favorable outcome after acute ischemic stroke. Leukoaraiosis, a marker of chronic ischemia, is a possible negative predictive factor of early recovery. However, its negative attenuating effects remain inadequately studied, leading to uncertainty in the prediction of outcomes after IVT. We aim to determine the influence of leukoaraiosis on early neurologic recovery.
    Journal of stroke and cerebrovascular diseases: the official journal of National Stroke Association 08/2014;
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    ABSTRACT: Background and Purpose: Developing improved methods for analysis of the modified Rankin Scale (mRS) remains a critical issue for the stroke research community. A recently proposed permutation-based approach is assumption-free and easily interpretable but computationally intensive and does not provide confidence intervals to quantify the precision of the effect size estimate. We aimed to develop a method to over-come these limitations. Methods: We propose a procedure using generalized odds ratios to estimate the odds that a patient who received the investigational treatment will have a better outcome than a patient receiving standard treatment. This approach was vali-dated against the permutation method using hypothetical clinical trial scenarios of neuroprotective effect, early recanali-zation effect, late recanalization effect, and random benefit. Results: The generalized odds ratio approach had strong agreement with the permutation approach provided sample size was >15 patients per treatment arm. Simulation estab-lished that the confidence intervals generated were accurate. Ignoring patient pairs with tied mRS scores overestimates the treatment effect compared with splitting tied mRS scores. Conclusions: In addition to all the advantages of the recently proposed permutation-based approach, our method generates confidence intervals without the need for intensive computa-tional power. The resulting generalized odds ratios are particu-larly suitable for inclusion in meta-analyses and have a simple and intuitive connection with the number-needed-to-treat measure.
    International Journal of Stroke 07/2014; · 4.03 Impact Factor
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    ABSTRACT: Objective Thyroid-peroxidase antibodies (TPOAb) and thyroglobulin antibodies (TGAb) are frequently measured to investigate thyroid dysfunction in pregnancy. Despite the recognized fall of these autoantibodies in pregnancy, there is limited guidance on the timing of such testing. We assessed optimal test timing of TPOAb/TGAb for detection of Hashimoto's thyroiditis and postpartum thyroid dysfunction (PPTD).DesignProspective longitudinal study with recruitment in Trimester-1.PatientsHealthy women ≤13weeks gestation from Mercy Hospital for Women, a tertiary obstetric hospital in Melbourne.MeasurementsSerum TPOAb, TGAb, TSH and fT4 were measured at Trimester-1(T1), Trimester-2(T2), Trimester-3(T3), and postpartum(PP) in each participant. Postpartum thyroid dysfunction (PPTD) was defined if TSH deviated from the assay's non-pregnant reference interval. Longitudinal random-effect logistic regression was used to investigate the association between time and positive/negative thyroid autoantibody status.ResultsSamples from 140 women at T1(12.0:10.3-13.0) (median:IQR weeks gestation); 95 at T2(24.3:23.0-25.9), 79 at T3(35.9:34.8-36.7) and 83 at PP(12.4:10.8-14.6 weeks postpartum) were attained. At T1, 13(9%) and 15(11%) women had positive TPOAb and TGAb, respectively. The odds of having a positive TPOAb was 96% lower at T2(OR=0.04 (95%CI:0.02-0.8;p=0.03)) and 97% lower at T3(OR=0.03(95%CI:0.001-0.6;p=0.02)) than at T1. Similarly, the odds of having a positive TGAb was 99.4% lower (OR=0.006(95%CI:0-0.3;p=0.01)) at T2, and 99.5% lower (OR=0.005(95%CI:0-0.4;p=0.02)) at T3 than at T1. The ROC analysis diagnostic ORs for a positive TPOAb and/or TGAb to predict PPTD were 7.8(95%CI:2.2-27.6), 1.2(95%CI:0-8.9), 2.0(95%CI:0-16.8), and 12.2(95%CI:3.3-44.9) at T1, T2, T3 and postpartum, respectively.ConclusionsA significant proportion of pregnant women lose their thyroid autoantibody positivity after T1. The gestation dependent loss of TPOAb/TGAb positivity and reduction in diagnostic accuracy for predicting PPTD limits the value of testing at T2 and T3.This article is protected by copyright. All rights reserved.
    Clinical Endocrinology 07/2014; · 3.40 Impact Factor
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    ABSTRACT: In acute stroke management, time efficiency in the continuum of patient management is critical. We aimed to determine if implementation of system improvements at our institution translated to reduced picture-to-puncture (P2P) times over a 6-year period.
    Journal of Neurointerventional Surgery 06/2014; · 2.50 Impact Factor
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    ABSTRACT: Background: Clinical deterioration in the acute stage of ischemic stroke powerfully predicts outcome and may serve as a marker for urgent intervention. However, accurate monitoring of acute stroke patients is hampered by the lack of validated continuous monitoring devices. We sought to assess the use of wireless accelerometry in this setting, hypothesizing that stroke patients would have a greater difference in movement between upper limbs than controls and that the magnitude of correlation between upper limb movements would be negatively associated with the National Institutes of Health Stroke Scale (NIHSS) score. Methods: In this pilot study, 20 patients with acute ischemic stroke and unilateral upper limb weakness and 10 controls were recruited from a comprehensive stroke centre. All subjects were fitted with two 3-axis accelerometers and underwent 24 h of continuous accelerometry recording of upper limb movements and repeat NIHSS assessments. The intra-class correlation coefficient (ICC), assessing the similarity (or otherwise) of spontaneous movements in each arm was calculated. The association between NIHSS (total and motor subset scores) and the magnitude of ICC was estimated by Spearman's rank correlation, receiver-operating characteristic curve analysis was performed and the optimal diagnostic threshold value of ICC was calculated. Results: The magnitude of the ICC was significantly associated with the baseline NIHSS score (p = 0.02) and non-significantly associated with the baseline NIHSS motor score (p = 0.08). At the optimal diagnostic threshold of ICC magnitude = 0.7, wireless accelerometry distinguished patients from controls with a sensitivity of 0.95, a specificity of 0.6 and a diagnostic odds ratio of 28.5. Conclusions: The wireless accelerometry system successfully detects a motor deficit in the setting of acute ischemic stroke, accurately differentiating patients from controls, and correlates well with the baseline NIHSS score. Its use is feasible in the acute stroke setting. Overall, it shows promise as a diagnostic tool to continuously monitor acute stroke patients but requires validation in a larger trial. © 2014 S. Karger AG, Basel.
    Cerebrovascular diseases (Basel, Switzerland). 06/2014; 37(5):336-341.
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    ABSTRACT: Background and PurposeIn acute ischemic stroke perfusion/diffusion-weighted image, mismatch using magnetic resonance imaging approximates the ischemic penumbra. For early time windows, mismatch salvage improves clinical outcomes, but uncertainty exists at later time epochs. We hypothesized that (a) mismatch may exist up to 48 h; (b) the proportion of mismatch salvage is time independent; and (c) when salvaged, it improves clinical outcomes. Methods Magnetic resonance imaging was performed within 48 h of ischemic stroke. Perfusion-weighted image was defined by relative Tmax two-second delay. Perfusion/diffusion-weighted image mismatch was the perfusion-weighted image not overlapped by the diffusion-weighted image when coregistered. Infarct volume and disability (modified Rankin Score) were assessed at three-months. Mismatch salvage was the region not overlapped by final infarction. Favorable outcome was defined as modified Rankin Score 0–1. ResultsSixty-six patients were studied [mean age 69·9 years (standard deviation 13·1), initial median National Institute of Health Stroke Scale 9·0 (interquartile range 6·0, 18·3)]. There was no relationship between time of stroke onset and the proportion of mismatch salvaged (P = 0·73). Age (adjusted odds ratio = 0·92, 95% confidence interval 0·86–0·98, P = 0·01), initial National Institute of Health Stroke Scale (adjusted odds ratio = 0·80, 95% confidence interval 0·70–0·92, P < 0·01), mismatch volume (adjusted odds ratio = 0·98, 95% confidence interval 0·968–0·1, P = 0·05), and percentage of mismatch salvage (adjusted odds ratio = 1·04, 95% confidence interval 0·99–1·07, P = 0·05) were independently associated with favorable outcome. Conclusion Using coregistered perfusion/diffusion-weighted image criteria, mismatch persists up to 48 h post stroke. For the whole group, the proportion of mismatch salvage remains independent of time and, although the effect is small, its salvage is independently associated with improved clinical outcomes at three-months. Larger sample sizes are needed to determine the time limit for mismatch salvage.
    International Journal of Stroke 04/2014; · 4.03 Impact Factor
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    ABSTRACT: To determine symptoms, signs, and etiology of brain attacks in children presenting to the emergency department (ED) as a first step for developing a pediatric brain attack pathway. Prospective observational study of children aged 1 month to 18 years with brain attacks (defined as apparently abrupt-onset focal brain dysfunction) and ongoing symptoms or signs on arrival to the ED. Exclusion criteria included epilepsy, hydrocephalus, head trauma, and isolated headache. Etiology was determined after review of clinical data, neuroimaging, and other investigations. A random-effects meta-analysis of similar adult studies was compared with the current study. There were 287 children (46% male) with 301 presentations over 17 months. Thirty-five percent arrived by ambulance. Median symptom duration before arrival was 6 hours (interquartile range 2-28 hours). Median time from triage to medical assessment was 22 minutes (interquartile range 6-55 minutes). Common symptoms included headache (56%), vomiting (36%), focal weakness (35%), numbness (24%), visual disturbance (23%), seizures (21%), and altered consciousness (21%). Common signs included focal weakness (31%), numbness (13%), ataxia (10%), or speech disturbance (8%). Neuroimaging included CT imaging (30%), which was abnormal in 27%, and MRI (31%), which was abnormal in 62%. The most common diagnoses included migraine (28%), seizures (15%), Bell palsy (10%), stroke (7%), and conversion disorders (6%). Relative proportions of conditions in children significantly differed from adults for stroke, migraine, seizures, and conversion disorders. Brain attack etiologies differ from adults, with stroke being the fourth most common diagnosis. These findings will inform development of ED clinical pathways for pediatric brain attacks.
    Neurology 03/2014; · 8.30 Impact Factor
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    ABSTRACT: Stroke thrombolysis is highly time-critical, but data on long-term effects of small reductions in treatment delays have not been available. Our objective was to quantify patient lifetime benefits gained from faster treatment. Observational prospective data of consecutive stroke patients treated with intravenous thrombolysis in Australian and Finnish centers (1998-2011; n=2258) provided distributions of age, sex, stroke severity, onset-to-treatment times, and 3-month modified Rankin Scale in daily clinical practice. Treatment effects derived from a pooled analysis of thrombolysis trials were used to model the shift in 3-month modified Rankin Scale distributions with reducing treatment delays, from which we derived the expected lifetime and level of long-term disability with faster treatment. Each minute of onset-to-treatment time saved granted on average 1.8 days of extra healthy life (95% prediction interval, 0.9-2.7). Benefit was observed in all groups: each minute provided 0.6 day in old severe (age, 80 years; National Institutes of Health Stroke Scale [NIHSS] score, 20) patients, 0.9 day in old mild (age, 80 years; NIHSS score, 4) patients, 2.7 days in young mild (age, 50 years; NIHSS score, 4) patients, and 3.5 days in young severe (age, 50 years; NIHSS score, 20) patients. Women gained slightly more than men over their longer lifetimes. In the whole cohort, each 15 minute decrease in treatment delay provided an average equivalent of 1 month of additional disability-free life. Realistically achievable small reductions in stroke thrombolysis delays would result in significant and robust average health benefits over patients' lifetimes. The awareness of concrete importance of speed could promote practice change.
    Stroke 03/2014; · 6.16 Impact Factor
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    ABSTRACT: Although intra-arterial therapy for acute ischemic stroke is associated with superior recanalization rates, improved clinical outcomes are inconsistently observed following successful recanalization. There is emerging concern that unfavorable arterial collateralization, though unproven, predetermines poor outcome. We hypothesized that poor leptomeningeal collateralization, assessed by preprocedural CTA, is associated with poor outcome in patients with acute ischemic stroke undergoing intra-arterial therapy. We retrospectively analyzed patients with acute ischemic stroke with intracranial ICA and/or MCA occlusions who received intra-arterial therapy. The collaterals were graded on CTA. Univariate and multivariate analyses were used to investigate the association between the dichotomized leptomeningeal collateral score and functional outcomes at 3-months mRS ≤2, mortality, and intracranial hemorrhages. Eighty-seven patients were included. The median age was 66 years (interquartile range, 54-76 years) and the median NIHSS score at admission was 18 (interquartile range, 14-20). The leptomeningeal collateral score 3 was found to have significant association with the good functional outcome at 3 months: OR = 3.13; 95% CI, 1.25-7.825; P = .016. This association remained significant when adjusted for the use of IV tissue plasminogen activator: alone, OR = 2.998; 95% CI, 1.154-7.786; P = .024; and for IV tissue plasminogen activator and other confounders (age, baseline NIHSS score, and Thrombolysis in Cerebral Infarction grades), OR = 2.985; 95% CI, 1.027-8.673; P = .045. We found that poor arterial collateralization, defined as a collateral score of <3, was associated with poor outcome, after adjustment for recanalization success. We recommend that future studies include collateral scores as one of the predictors of functional outcome.
    American Journal of Neuroradiology 01/2014; · 3.17 Impact Factor
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    ABSTRACT: ABSTRACT Background: Many stroke research trials do not include assessment of cognitive function. A Very Early Rehabilitation Trial (AVERT) is an international multicenter study that includes the Montreal Cognitive Assessment (MoCA) as an outcome. At the Malaysian AVERT site, completion of the MoCA has been limited by low English proficiency in some participants. We aimed to develop a Bahasa Malaysia (BM) version of the MoCA and to validate it in a stroke population. Methods: The original English version of the MoCA was translated into BM and then back-translated to ensure accuracy. Feasibility testing in a group of stroke patients prompted minor changes to the BM MoCA. In the validation phase, a larger group of bilingual stroke patients completed both the original English MoCA and the finalized BM MoCA, with presentation order counter-balanced. Results: Forty stroke patients participated, with a mean age of 57.2 (SD = 10.3). Agreement between BM MoCA and English MoCA was strong (intra-class correlation coefficient = 0.81, 95% CI 0.68-0.90). Scores on BM MoCA were slightly higher than scores on English MoCA (median absolute difference = 2.0, IQR 0-3.5), and this difference was present regardless of which version was completed first. Conclusions: The existence of a validated BM version of the MoCA will be of major benefit to clinicians and researchers in Malaysia and the wider South-east Asian region, where the Malay language is used by over 200 million people.
    International Psychogeriatrics 01/2014; · 2.19 Impact Factor
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    ABSTRACT: Patients with stroke are more likely to have impaired autonomic nervous function and abnormal circadian blood pressure (BP) patterns. It remains unclear whether circadian BP patterns in patients with transient ischemic attack or minor stroke (National Institutes of Health Stroke Scale ≤3) differ from those in the normal population. Participants were assessed using a 24-hour ambulatory BP monitor and a short-term measurement of heart rate variability. There were 76 patients (mean age, 67.2 years; 57.9% men; and 61.8% transient ischemic attack) and 82 controls (65.6 years; 54.9% men). A history of hypertension was more prevalent in patients (72.4%; controls 48.8%). Circadian BP patterns were distributed similarly among patients and controls, and heart rate variability was also consistent between patients and controls. In contrast to previous findings among patients with acute stroke, patients with transient ischemic attack or minor stroke had similar BP patterns and autonomic nervous system function, when compared with controls.
    Stroke 01/2014; · 6.16 Impact Factor
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    ABSTRACT: Background. Sedentary behaviour is associated with health risks, independent of physical activity. This study aimed to investigate patterns of sedentary behaviour and physical activity among stroke survivors in rehabilitation hospitals. Methods. Stroke survivors admitted to four Swedish hospital-based rehabilitation units were recruited ≥7 days since stroke onset and their activity was measured using behavioural mapping. Sedentary behaviour was defined as lying down or sitting supported. Results. 104 patients were observed (53% men). Participants spent an average of 74% (standard deviation, SD 21%) of the observed day in sedentary activities. Continuous sedentary bouts of ≥1 hour represented 44% (SD 32%) of the observed day. A higher proportion (30%, SD 7%) of participants were physically active between 9:00 AM and 12:30 PM, compared to the rest of the observed day (23%, SD 6%, P < 0.0005). Patients had higher odds of being physically active in the hall (odds ratio, OR 1.7, P = 0.001) than in the therapy area. Conclusions. The time stroke survivors spend in stroke rehabilitation units may not be used in the most efficient way to promote maximal recovery. Interventions to promote reduced sedentary time could help improve outcome and these should be tested in clinical trials.
    Stroke research and treatment. 01/2014; 2014:591897.
  • Kristian Rotaru, Leonid Churilov, Andrew Flitman
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    ABSTRACT: Purpose ‐ The current state of theory-building in the field of operations and supply chain management (OSCM) is in a strong need of rigorous, empirically based theories that enhance understanding of the causal relationships between the structural elements and properties of the business processes. In this research note the authors propose the critical realism (CR) philosophy of science as a particularly suitable philosophical position (not to the exclusion of others) to review the mechanisms of OSCM knowledge generation and to provide philosophical grounding and methodological guidance for both OSCM theory building and testing. Design/methodology/approach ‐ To demonstrate potential benefits of CR-based structured approach to knowledge generation in OSCM research, this conceptual paper uses a case study that illustrates the adoption of one of the OSCM theories ‐ i.e. the theory of swift, even flow. Findings ‐ CR interprets the accumulated empirical information about OSCM phenomena as observable manifestations of the underlying causal mechanisms that cannot be perceived otherwise. CR can provide epistemological support to the choice of performance measures that manifest the underlying causal mechanisms of interest. Extensive accumulation of empirical data from multiple innovative sources will not dramatically add to understanding of the system under investigation, unless and until the underlying causal mechanisms that trigger the observed behaviour are identified and tested. The CR abductive mode of reasoning emphasises the role of uncertainty in complex process behaviours and can facilitate enrichment and refutation of OSCM theories. Originality/value ‐ CR has a clear potential to contribute to OSCM research by enabling better understanding of causal relationships underlying complex behaviours of different elements of business process by providing robust and relevant mechanisms of generating knowledge about business processes that explicitly link empirical and causal aspects of theory building and testing.
    Supply Chain Management 01/2014; 19(2). · 2.92 Impact Factor

Publication Stats

549 Citations
303.73 Total Impact Points

Institutions

  • 2011–2014
    • The Florey Institute of Neuroscience and Mental Health
      Melbourne, Victoria, Australia
  • 2008–2014
    • University of Melbourne
      • Florey Institute of Neuroscience and Mental Health
      Melbourne, Victoria, Australia
  • 2013
    • La Trobe University
      • Department of Physiotherapy
      Melbourne, Victoria, Australia
    • Victoria University Melbourne
      Melbourne, Victoria, Australia
    • RMIT University
      • School of Mathematical and Geospatial Sciences
      Melbourne, Victoria, Australia
    • Xuanwu hospital
      Peping, Beijing, China
    • Royal Melbourne Hospital
      Melbourne, Victoria, Australia
    • Fudan University
      • Department of Neurology
      Shanghai, Shanghai Shi, China
  • 2012
    • Neuroscience Research Australia
      Sydney, New South Wales, Australia
  • 2011–2012
    • National Neuroscience Institute
      • Department of Neurology
      Singapore, Singapore
  • 2003–2008
    • Monash University (Australia)
      Melbourne, Victoria, Australia
  • 2006
    • University of Vic
      Vic, Catalonia, Spain