Medicine (Austin & Northern Health) - Research Publications

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    A mixed-methods feasibility study of a new digital health support package for people after stroke: the Recovery-focused Community support to Avoid readmissions and improve Participation after Stroke (ReCAPS) intervention
    Cameron, J ; Lannin, NA ; Harris, D ; Andrew, NE ; Kilkenny, MF ; Purvis, T ; Thrift, AG ; Thayabaranathan, T ; Ellery, F ; Sookram, G ; Hackett, M ; Kneebone, I ; Drummond, A ; Cadilhac, DA (BMC, 2022-11-19)
    BACKGROUND: Evidence for digital health programmes to support people living with stroke is growing. We assessed the feasibility of a protocol and procedures for the Recovery-focused Community support to Avoid readmissions and improve Participation after Stroke (ReCAPS) trial. METHODS: We conducted a mixed-method feasibility study. Participants with acute stroke were recruited from three hospitals (Melbourne, Australia). Eligibility: Adults with stroke discharged from hospital to home within 10 days, modified Rankin Score 0-4 and prior use of Short Message System (SMS)/email. While in hospital, recruited participants contributed to structured person-centred goal setting and completed baseline surveys including self-management skills and health-related quality of life. Participants were randomised 7-14 days after discharge via REDCap® (1:1 allocation). Following randomisation, the intervention group received a 12-week programme of personalised electronic support messages (average 66 messages sent by SMS or email) aligned with their goals. The control group received six electronic administrative messages. Feasibility outcomes included the following: number of patients screened and recruited, study retainment, completion of outcome measures and acceptability of the ReCAPS intervention and trial procedures (e.g. participant satisfaction survey, clinician interviews). Protocol fidelity outcomes included number of goals developed (and quality), electronic messages delivered, stop messages received and engagement with messages. We undertook inductive thematic analysis of interview/open-text survey data and descriptive analysis of closed survey questions. RESULTS: Between November 2018 and October 2019, 312 patients were screened; 37/105 (35%) eligible patients provided consent (mean age 61 years; 32% female); 33 were randomised (17 to intervention). Overall, 29 (88%) participants completed the12-week outcome assessments with 12 (41%) completed assessments in the allocated timeframe and 16 also completing the satisfaction survey (intervention=10). Overall, trial participants felt that the study was worthwhile and most would recommend it to others. Six clinicians participated in one of three focus group interviews; while they reported that the trial and the process of goal setting were acceptable, they raised concerns regarding the additional time required to personalise goals. CONCLUSION: The study protocol and procedures were feasible with acceptable retention of participants. Consent and goal personalisation procedures should be centralised for the phase III trial to reduce the burden on hospital clinicians. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry, ACTRN12618001468213 (date 31/08/2018); Universal Trial Number: U1111-1206-7237.
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    Prevalence and Significance of Impaired Microvascular Tissue Reperfusion Despite Macrovascular Angiographic Reperfusion (No-Reflow)
    Ng, FC ; Churilov, L ; Yassi, N ; Kleinig, TJ ; Thijs, V ; Wu, T ; Shah, D ; Dewey, H ; Sharma, G ; Desmond, P ; Yan, B ; Parsons, M ; Donnan, G ; Davis, S ; Mitchell, P ; Campbell, B (LIPPINCOTT WILLIAMS & WILKINS, 2022-02-22)
    BACKGROUND AND OBJECTIVES: The relevance of impaired microvascular tissue-level reperfusion despite complete upstream macrovascular angiographic reperfusion (no-reflow) in human stroke remains controversial. We investigated the prevalence and clinical-radiologic features of this phenomenon and its associations with outcomes in 3 international randomized controlled thrombectomy trials with prespecified follow-up perfusion imaging. METHODS: In a pooled analysis of the Extending the Time for Thrombolysis in Emergency Neurological Deficits-Intra-Arterial (EXTEND-IA; ClinicalTrials.gov NCT01492725), Tenecteplase Versus Alteplase Before Endovascular Therapy for Ischemic Stroke (EXTEND-IA TNK; NCT02388061), and Determining the Optimal Dose of Tenecteplase Before Endovascular Therapy for Ischaemic Stroke (EXTEND-IA TNK Part 2; NCT03340493) trials, patients undergoing thrombectomy with final angiographic expanded Treatment in Cerebral Infarction score of 2c to 3 score for anterior circulation large vessel occlusion and 24-hour follow-up CT or MRI perfusion imaging were included. No-reflow was defined as regions of visually demonstrable persistent hypoperfusion on relative cerebral blood volume or flow maps within the infarct and verified quantitatively by >15% asymmetry compared to a mirror homolog in the absence of carotid stenosis or reocclusion. RESULTS: Regions of no-reflow were identified in 33 of 130 patients (25.3%), encompassed a median of 60.2% (interquartile range 47.8%-70.7%) of the infarct volume, and involved both subcortical (n = 26 of 33, 78.8%) and cortical (n = 10 of 33, 30.3%) regions. Patients with no-reflow had a median 25.2% (interquartile range 16.4%-32.2%, p < 0.00001) relative cerebral blood volume interside reduction and 19.1% (interquartile range 3.9%-28.3%, p = 0.00011) relative cerebral blood flow reduction but similar mean transit time (median -3.3%, interquartile range -11.9% to 24.4%, p = 0.24) within the infarcted region. Baseline characteristics were similar between patients with and those without no-reflow. The presence of no-reflow was associated with hemorrhagic transformation (adjusted odds ratio [aOR] 1.79, 95% confidence interval [CI] 2.32-15.57, p = 0.0002), greater infarct growth (β = 11.00, 95% CI 5.22-16.78, p = 0.00027), reduced NIH Stroke Scale score improvement at 24 hours (β = -4.06, 95% CI 6.78-1.34, p = 0.004) and being dependent or dead at 90 days as assessed by the modified Rankin Scale (aOR 3.72, 95% CI 1.35-10.20, p = 0.011) in multivariable analysis. DISCUSSION: Cerebral no-reflow in humans is common, can be detected by its characteristic perfusion imaging profile using readily available sequences in the clinical setting, and is associated with posttreatment complications and being dependent or dead. Further studies evaluating the role of no-reflow in secondary injury after angiographic reperfusion are warranted. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that cerebral no-reflow on CT/MRI perfusion imaging at 24 hours is associated with posttreatment complications and poor 3-month functional outcome.
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    Endovascular Thrombectomy Versus Medical Management in Isolated M2 Occlusions: Pooled Patient-Level Analysis from the EXTEND-IA Trials, INSPIRE, and SELECT Studies
    Sarraj, A ; Parsons, M ; Bivard, A ; Hassan, AE ; Abraham, MG ; Wu, T ; Kleinig, T ; Lin, L ; Chen, C ; Levi, C ; Dong, Q ; Cheng, X ; Butcher, KS ; Choi, P ; Yassi, N ; Shah, D ; Sharma, G ; Pujara, D ; Shaker, F ; Blackburn, S ; Dewey, H ; Thijs, V ; Sitton, CW ; Donnan, GA ; Mitchell, PJ ; Yan, B ; Grotta, JG ; Albers, GW ; Davis, SM ; Campbell, B (WILEY, 2022-05)
    OBJECTIVE: The objective of this study was to evaluate functional and safety outcomes of endovascular thrombectomy (EVT) versus medical management (MM) in patients with M2 occlusion and examine their association with perfusion imaging mismatch and stroke severity. METHODS: In a pooled, patient-level analysis of 3 randomized controlled trials (EXTEND-IA, EXTEND-and IA-TNK parts 1 and 2) and 2 prospective nonrandomized studies (INSPIRE and SELECT), we evaluated EVT association with 90-day functional independence (modified Rankin Scale [mRS] = 0-2) in isolated M2 occlusions as compared to medical management overall and in subgroups by mismatch profile status and stroke severity. RESULTS: We included 517 patients (EVT = 195 and MM = 322), baseline median (interquartile range [IQR]) National Institutes of Health Stroke Scale (NIHSS) was 13 (8-19) in EVT versus 10 (6-15) in MM, p < 0.001. Pretreatment ischemic core did not differ (EVT = 10 [0-24] ml vs MM = 9 [3-21] ml, p = 0.59). Compared to MM, EVT was more frequently associated with functional independence (68.3 vs 61.6%, adjusted odds ratio [aOR] = 2.42, 95% confidence interval [CI] = 1.25-4.67, p = 0.008, inverse probability of treatment weights [IPTW]-OR = 1.75, 95% CI = 1.00-3.75, p = 0.05) with a shift toward better mRS outcomes (adjusted cOR = 2.02, 95% CI:1.23-3.29, p = 0.005), and lower mortality (5 vs 10%, aOR = 0.32, 95% CI = 0.12-0.87, p = 0.025). EVT was associated with higher functional independence in patients with a perfusion mismatch profile (EVT = 70.7% vs MM = 61.3%, aOR = 2.29, 95% CI = 1.09-4.79, p = 0.029, IPTW-OR = 2.02, 1.08-3.78, p = 0.029), whereas no difference was found in those without mismatch (EVT = 43.8% vs MM = 62.7%, p = 0.17, IPTW-OR: 0.71, 95% CI = 0.18-2.78, p = 0.62). Functional independence was more frequent with EVT in patients with moderate or severe strokes, as defined by baseline NIHSS above any thresholds from 6 to 10, whereas there was no difference between groups with milder strokes below these thresholds. INTERPRETATION: In patients with M2 occlusion, EVT was associated with improved clinical outcomes when compared to MM. This association was primarily observed in patients with a mismatch profile and those with higher stroke severity. ANN NEUROL 2022;91:629-639.
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    Healthy Life-Year Costs of Treatment Speed From Arrival to Endovascular Thrombectomy in Patients With Ischemic Stroke A Meta-analysis of Individual Patient Data From 7 Randomized Clinical Trials
    Almekhlafi, MA ; Goyal, M ; Dippel, DWJ ; Majoie, CBLM ; Campbell, BCV ; Muir, KW ; Demchuk, AM ; Bracard, S ; Guillemin, F ; Jovin, TG ; Mitchell, P ; White, P ; Hill, MD ; Brown, S ; Saver, JL (AMER MEDICAL ASSOC, 2021-06)
    IMPORTANCE: The benefits of endovascular thrombectomy (EVT) are time dependent. Prior studies may have underestimated the time-benefit association because time of onset is imprecisely known. OBJECTIVE: To assess the lifetime outcomes associated with speed of endovascular thrombectomy in patients with acute ischemic stroke due to large-vessel occlusion (LVO). DATA SOURCES: PubMed was searched for randomized clinical trials of stent retriever thrombectomy devices vs medical therapy in patients with anterior circulation LVO within 12 hours of last known well time, and for which a peer-reviewed, complete primary results article was published by August 1, 2020. STUDY SELECTION: All randomized clinical trials of stent retriever thrombectomy devices vs medical therapy in patients with anterior circulation LVO within 12 hours of last known well time were included. DATA EXTRACTION/SYNTHESIS: Patient-level data regarding presenting clinical and imaging features and functional outcomes were pooled from the 7 retrieved randomized clinical trials of stent retriever thrombectomy devices (entirely or predominantly) vs medical therapy. All 7 identified trials published in a peer-reviewed journal (by August 1, 2020) contributed data. Detailed time metrics were collected including last known well-to-door (LKWTD) time; last known well/onset-to-puncture (LKWTP) time; last known well-to-reperfusion (LKWR) time; door-to-puncture (DTP) time; and door-to-reperfusion (DTR) time. MAIN OUTCOMES AND MEASURES: Change in healthy life-years measured as disability-adjusted life-years (DALYs). DALYs were calculated as the sum of years of life lost (YLL) owing to premature mortality and years of healthy life lost because of disability (YLD). Disability weights were assigned using the utility-weighted modified Rankin Scale. Age-specific life expectancies without stroke were calculated from 2017 US National Vital Statistics. RESULTS: Among the 781 EVT-treated patients, 406 (52.0%) were early-treated (LKWTP ≤4 hours) and 375 (48.0%) were late-treated (LKWTP >4-12 hours). In early-treated patients, LKWTD was 188 minutes (interquartile range, 151.3-214.8 minutes) and DTP 105 minutes (interquartile range, 76-135 minutes). Among the 298 of 380 (78.4%) patients with substantial reperfusion, median DTR time was 145.0 minutes (interquartile range, 111.5-185.5 minutes). Care process delays were associated with worse clinical outcomes in LKW-to-intervention intervals in early-treated patients and in door-to-intervention intervals in early-treated and late-treated patients, and not associated with LKWTD intervals, eg, in early-treated patients, for each 10-minute delay, healthy life-years lost were DTP 1.8 months vs LKWTD 0.0 months; P < .001. Considering granular time increments, the amount of healthy life-time lost associated with each 1 second of delay was DTP 2.2 hours and DTR 2.4 hours. CONCLUSIONS AND RELEVANCE: In this study, care delays were associated with loss of healthy life-years in patients with acute ischemic stroke treated with EVT, particularly in the postarrival time period. The finding that every 1 second of delay was associated with loss of 2.2 hours of healthy life may encourage continuous quality improvement in door-to-treatment times.
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    Fatal and Nonfatal Events Within 14 days After Early, Intensive Mobilization Poststroke
    Bernhardt, J ; Borschmann, K ; Collier, JM ; Thrift, AG ; Langhorne, P ; Middleton, S ; Lindley, RI ; Dewey, HM ; Bath, P ; Said, CM ; Churilov, L ; Ellery, F ; Bladin, C ; Reid, CM ; Frayne, JH ; Srikanth, V ; Read, SJ ; Donnan, GA (LIPPINCOTT WILLIAMS & WILKINS, 2021-02-23)
    OBJECTIVE: This tertiary analysis from A Very Early Rehabilitation Trial (AVERT) examined fatal and nonfatal serious adverse events (SAEs) at 14 days. METHOD: AVERT was a prospective, parallel group, assessor blinded, randomized international clinical trial comparing mobility training commenced <24 hours poststroke, termed very early mobilization (VEM), to usual care (UC). Primary outcome was assessed at 3 months. Patients with ischemic or hemorrhagic stroke within 24 hours of onset were included. Treatment with thrombolytics was allowed. Patients with severe premorbid disability or comorbidities were excluded. Interventions continued for 14 days or hospital discharge if less. The primary early safety outcome was fatal SAEs within 14 days. Secondary outcomes were nonfatal SAEs classified as neurologic, immobility-related, and other. Mortality influences were assessed using binary logistic regression adjusted for baseline stroke severity (NIH Stroke Scale [NIHSS] score) and age. RESULTS: A total of 2,104 participants were randomized to VEM (n = 1,054) or UC (n = 1,050) with a median age of 72 years (interquartile range [IQR] 63-80) and NIHSS 7 (IQR 4-12). By 14 days, 48 had died in VEM, 32 in UC, age and stroke severity adjusted odds ratio of 1.76 (95% confidence interval 1.06-2.92, p = 0.029). Stroke progression was more common in VEM. Exploratory subgroup analyses showed higher odds of death in intracerebral hemorrhage and >80 years subgroups, but there was no significant treatment by subgroup interaction. No difference in nonfatal SAEs was found. CONCLUSION: While the overall case fatality at 14 days poststroke was only 3.8%, mortality adjusted for age and stroke severity was increased with high dose and intensive training compared to usual care. Stroke progression was more common in VEM. REGISTRATION: Australian New Zealand Clinical Trials Registry, ACTRN12606000185561. CLASSIFICATION OF EVIDENCE: This study provides Class I evidence that very early mobilization increases mortality at 14 days poststroke.
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    Improving acute stroke care in regional hospitals: clinical evaluation of the Victorian Stroke Telemedicine program
    Bladin, CF ; Kim, J ; Bagot, KL ; Vu, M ; Moloczij, N ; Denisenko, S ; Price, C ; Pompeani, N ; Arthurson, L ; Hair, C ; Rabl, J ; O'Shea, M ; Groot, P ; Bolitho, L ; Campbell, BC ; Dewey, HM ; Donnan, GA ; Cadilhac, DA (WILEY, 2020-05)
    OBJECTIVES: To evaluate the impact of the Victorian Stroke Telemedicine (VST) program during its first 12 months on the quality of care provided to patients presenting with suspected stroke to hospitals in regional Victoria. DESIGN: Historical controlled cohort study comparing outcomes during a 12-month control period with those for the initial 12 months of full implementation of the VST program at each hospital. SETTING: 16 hospitals in regional Victoria that participated in the VST program between 1 January 2010 and 30 January 2016. PARTICIPANTS: Adult patients with suspected stroke presenting to the emergency departments of the participating hospitals. MAIN OUTCOME MEASURES: Indicators for key processes of care, including symptom onset-to-arrival, door-to-first medical review, and door-to-CT times; provision and timeliness of provision of thrombolysis to patients with ischaemic stroke. RESULTS: 2887 patients with suspected stroke presented to participating emergency departments during the control period, 3178 during the intervention period; the patient characteristics were similar for both periods. A slightly larger proportion of patients with ischaemic stroke who arrived within 4.5 hours of symptom onset received thrombolysis during the intervention than during the control period (37% v 30%). Door-to-CT scan time (median, 25 min [IQR, 13-49 min] v 34 min [IQR, 18-76 min]) and door-to-needle time for stroke thrombolysis (73 min [IQR, 56-96 min] v 102 min [IQR, 77-128 min]) were shorter during the intervention. The proportions of patients who received thrombolysis and had a symptomatic intracerebral haemorrhage (4% v 16%) or died in hospital (6% v 20%) were smaller during the intervention period. CONCLUSIONS: Telemedicine has provided Victorian regional hospitals access to expert care for emergency department patients with suspected acute stroke. Eligible patients with ischaemic stroke are now receiving stroke thrombolysis more quickly and safely.
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    Discovery and Longitudinal Evaluation of Candidate Biomarkers for Ischaemic Stroke by Mass Spectrometry-Based Proteomics
    Dagonnier, M ; Cooke, IR ; Faou, P ; Sidon, TK ; Dewey, HM ; Donnan, GA ; Howells, DW (SAGE PUBLICATIONS LTD, 2017-12-20)
    Application of acute therapies such as thrombolysis for ischaemic stroke (IS) is constrained because of diagnostic uncertainty and the dynamic nature of stroke biology. To investigate changes in blood proteins after stroke and as a result of thrombolysis treatment we performed label-free quantitative proteomics on serum samples using high-resolution mass spectrometry and long high-performance liquid chromatography gradient (5 hours) combined with a 50-cm column to optimise the peptide separation. We identified (false discovery rate [FDR]: 1%) and quantified a total of 574 protein groups from a total of 92 samples from 30 patients. Ten patients were treated by thrombolysis as part of a randomised placebo-controlled trial and up to 5 samples were collected from each individual at different time points after stroke. We identified 26 proteins differently expressed by treatment group (FDR: 5%) and significant changes of expression over time for 23 proteins (FDR: 10%). Molecules such as fibrinogen and C-reactive protein showed expression profiles with a high-potential clinical utility in the acute stroke setting. Protein expression profiles vary acutely in the blood after stroke and have the potential to allow the construction of a stroke clock and to have an impact on IS treatment decision making.
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    Family physician decisions following stroke symptom onset and delay times to ambulance call
    Mosley, I ; Nicol, M ; Donnan, G ; Dewey, H (BMC, 2011-08-04)
    BACKGROUND: For stroke patients, calling an ambulance has been shown to be associated with faster times to hospital than contacting a family physician. However little is known about the impact of decisions made by family physicians on delay times for stroke patients once they have been called.We aimed to test the hypotheses that among ambulance transported stroke patients:• Factors associated with first calling a family physician, could be identified.• Time to ambulance call will be longer when a family physician is first contacted.• Medical examination prior to the ambulance call will be associated with longer delay times. METHODS: For 6 months in 2004, all ambulance-transported stroke patients who presented from a defined region in Melbourne, Australia to one of three hospitals were assessed. Ambulance and hospital records were analysed. The patient and the person who called the ambulance were interviewed to obtain their description of the stroke event. RESULTS: 198 patients were included in the study. In 32% of cases an ambulance was first called. No demographic or situational factors were associated with first calling a doctor. Patients with a history of stroke or TIA were less likely to call a doctor following symptom onset (p = 0.01). Patients with a severe stroke (Glasgow Coma Scale < 9) never called a doctor first.When a family physician was contacted (22% of cases), the time to ambulance call was significantly longer than when an ambulance was first called (p = 0.0018) (median 143 and 44 minutes, respectively). In 36% of calls to a family physician, the doctor elected to first examine the patient. Time to ambulance call was shorter when the doctor vetted the call and advised the caller to immediately call an ambulance (45%) (median 412 and 92 minutes respectively: p = 0.06). CONCLUSION: Time delays to ambulance call were significantly longer for stroke patients when a family physician was first contacted. Further extensive delays were experienced by patients when the family physician elected to examine the patient.Family physicians and their staff have an important role to play in averting potential delays for stroke patients by screening calls and providing immediate advice to "call an ambulance".
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    Integrating acute stroke telemedicine consultations into specialists' usual practice: a qualitative analysis comparing the experience of Australia and the United Kingdom
    Bagot, KL ; Cadilhac, DA ; Bladin, CF ; Watkins, CL ; Vu, M ; Donnan, GA ; Dewey, HM ; Emsley, HCA ; Davies, DP ; Day, E ; Ford, GA ; Price, CI ; May, CR ; McLoughlin, ASR ; Gibson, JME ; Lightbody, CE (BMC, 2017-11-21)
    BACKGROUND: Stroke telemedicine can reduce healthcare inequities by increasing access to specialists. Successful telemedicine networks require specialists adapting clinical practice to provide remote consultations. Variation in experiences of specialists between different countries is unknown. To support future implementation, we compared perceptions of Australian and United Kingdom specialists providing remote acute stroke consultations. METHODS: Specialist participants were identified using purposive sampling from two new services: Australia's Victorian Stroke Telemedicine Program (n = 6; 2010-13) and the United Kingdom's Cumbria and Lancashire telestroke network (n = 5; 2010-2012). Semi-structured interviews were conducted pre- and post-implementation, recorded and transcribed verbatim. Deductive thematic and content analysis (NVivo) was undertaken by two independent coders using Normalisation Process Theory to explore integration of telemedicine into practice. Agreement between coders was M = 91%, SD = 9 and weighted average κ = 0.70. RESULTS: Cross-cultural similarities and differences were found. In both countries, specialists described old and new consulting practices, the purpose and value of telemedicine systems, and concerns regarding confidence in the assessment and diagnostic skills of unknown colleagues requesting telemedicine support. Australian specialists discussed how remote consultations impacted on usual roles and suggested future improvements, while United Kingdom specialists discussed system governance, policy and procedures. CONCLUSION: Australian and United Kingdom specialists reported telemedicine required changes in work practice and development of new skills. Both groups described potential for improvements in stroke telemedicine systems with Australian specialists more focused on role change and the United Kingdom on system governance issues. Future research should examine if cross-cultural variation reflects different models of care and extends to other networks.
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    Hyperacute changes in blood mRNA expression profiles of rats after middle cerebral artery occlusion: Towards a stroke time signature.
    Dagonnier, M ; Wilson, WJ ; Favaloro, JM ; Rewell, SSJ ; Lockett, LJ ; Sastra, SA ; Jeffreys, AL ; Dewey, HM ; Donnan, GA ; Howells, DW ; Boltze, J (Public Library of Science (PLoS), 2018)
    Stroke evolution is a highly dynamic but variable disease which makes clinical decision making difficult. Biomarker discovery programs intended to aid clinical decision making have however largely ignored the rapidity of stroke evolution. We have used gene array technology to determine blood mRNA expression changes over the first day after stroke in rats. Blood samples were collected from 8 male spontaneously hypertensive rats at 0, 1, 2, 3, 6 and 24h post stroke induction by middle cerebral artery occlusion. RNA was extracted from whole blood stabilized in PAXgene tubes and mRNA expression was detected by oligonucleotide Affymetrix microarray. Using a pairwise comparison model, 1932 genes were identified to vary significantly over time (p≤0.5x10(-7)) within 24h after stroke. Some of the top20 most changed genes are already known to be relevant to the ischemic stroke physiopathology (e.g. Il-1R, Nos2, Prok2). Cluster analysis showed multiple stereotyped and time dependent profiles of gene expression. Direction and rate of change of expression for some profiles varied dramatically during these 24h. Profiles with potential clinical utility including hyper acute or acute transient upregulation (with expression peaking from 2 to 6h after stroke and normalisation by 24h) were identified. We found that blood gene expression varies rapidly and stereotypically after stroke in rats. Previous researchers have often missed the optimum time for biomarker measurement. Temporally overlapping profiles have the potential to provide a biological "stroke clock" able to tell the clinician how far an individual stroke has evolved.