Martin Dennis

University of Aberdeen, Aberdeen, Scotland, United Kingdom

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Publications (274)2267.84 Total impact

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    ABSTRACT: The CLOTS 3 trial showed that intermittent pneumatic compression (IPC) reduced the risk of DVT and improved survival after stroke. To provide additional information which may help clinicians target IPC on the most appropriate patients by exploring the variation in its effects on subgroups defined by predicted prognosis. A multicentre, parallel group, randomized trial enrolled immobile acute stroke patients and allocated them to IPC or no IPC. The primary outcome was proximal DVT at 30 days. Secondary outcomes at six-months included survival, disability, quality of life, and hospital costs. We stratified patients into quintiles according to their predicted prognosis at randomization, based on the Six Simple Variable model. Between December 2008 and September 2012, we enrolled 2876 patients in 94 UK hospitals. Patients with the best predicted outcome had the lowest absolute risk of proximal DVT (6·7%) and death by six-months (9·3%). Allocation to IPC had little effect on DVT, survival, disability, quality of life, hospital length of stay, or costs. In patients with the worst predicted outcomes, the overall risk of DVT and death was 16·0% and 51·3%, respectively. IPC reduced DVT (odds reduction 34%) and improved survival 17% and significantly increased length of stay and hospital costs. In the three intermediate quintiles, IPC reduced the odds of DVT (35-43%) and improved survival (11-13%). Disability and quality of life at six-months depended on baseline severity but was not influenced significantly by IPC. IPC appears to reduce the risk of DVT and probably improves survival in all immobile stroke patients, other than the fifth with the best prognosis. It therefore seems reasonable to recommend that IPC should be considered in all immobile stroke patients, but that the final decision should be based on a judgment about the individual's prognosis. In some, their prognosis for survival with an acceptable quality of life will be so poor that use of IPC might be considered futile, while at the other end of the spectrum, patients' risk of DVT, and of dying from VTE, may not be high enough to justify the modest cost and inconvenience of IPC use. © 2015 The Authors. International Journal of Stroke published by John Wiley & Sons Ltd on behalf of World Stroke Organization.
    International Journal of Stroke 08/2015; DOI:10.1111/ijs.12598 · 4.03 Impact Factor
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    ABSTRACT: Background The presence of a ‘weekend’ effect has been shown across a range of medical conditions, but has not been consistently observed for patients with stroke. Aims We investigated the impact of admission time on a range of process and outcome measures after stroke. Methods Using routine data from National Scottish data sets (2005–2013), time of admission was categorised into weekday, weeknight and weekend/public holidays. The main process measures were swallow screen on day of admission (day 0), brain scan (day 0 or 1), aspirin (day 0 or 1), admission to stroke unit (day 0 or 1), and thrombolysis administration. After case-mix adjustment, multivariable logistic regression was used to estimate the OR for mortality and discharge to home/usual place of residence. Results There were 52 276 index stroke events. Compared to weekday, the adjusted OR (95%CI) for early stroke unit admission was 0.81 (0.77 to 0.85) for weeknight admissions and 0.64 (0.61 to 0.67) for weekend/holiday admissions; early brain scan 1.30 (0.87 to 1.94) and 1.43 (0.95 to 2.18); same day swallow screen 0.86 (0.81 to 0.91) and 0.85 (0.81 to 0.90); thrombolysis 0.85 (0.75 to 0.97) and 0.85 (0.75 to 0.97), respectively. Seven-day mortality, 30-day mortality and 30-day discharge for weekend admission compared to weekday was 1.17 (1.05 to 1.30); 1.08 (1.00 to 1.17); and 0.90 (0.85 to 0.95), respectively. Conclusions Patients with stroke admitted out of hours and at weekends or public holidays are less likely to be managed according to current guidelines. They experience poorer short-term outcomes than those admitted during normal working hours, after correcting for known independent predictors of outcome and early mortality.
    Journal of Neurology Neurosurgery & Psychiatry 08/2015; DOI:10.1136/jnnp-2015-311273 · 5.58 Impact Factor
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    ABSTRACT: The cause of lacunar ischemic stroke, a clinical feature of cerebral small vessel disease (SVD), is largely unknown. Inflammation and endothelial dysfunction have been implicated. Plasma biomarkers could provide mechanistic insights but current data are conflicting. White matter hyperintensities (WMHs) are an important imaging biomarker of SVD. It is unknown if plasma biomarkers add predictive capacity beyond age and vascular risk factors in explaining WMH. We prospectively recruited patients presenting with non-disabling ischemic stroke, classifying them clinically and with the help of MRI as lacunar or cortical. We measured biomarkers of inflammation, endothelial dysfunction and hemostasis for >1 month after stroke and compared biomarker between stroke subtypes. We quantitatively calculated WMH. We used multiple linear regression analysis to model WMH as a function of age, sex, hypertension and smoking (the baseline model). We fitted exploratory models using plasma biomarkers as predictor variables to assess model improvement over baseline. We recruited 125 patients. The lacunar group (n = 65) had lower tissue plasminogen activator (t-PA) levels in unadjusted (7.39 vs. 8.59 ng/ml, p = 0.029) and adjusted (p = 0.035) analyses compared with the cortical group (n = 60). There were no significant differences in the other plasma biomarkers. The results for t-PA were consistent with an updated meta-analysis, although the effect remains non-significant (standardized mean difference -0.08 (95% CI -0.25 to 0.09)). The baseline regression model explained 29% of the variance in quantitative WMH (R(2) 0.289). Inflammatory biomarkers showed minor improvement over baseline (R(2) 0.291), but the other plasma biomarkers did not improve the baseline model. Plasma t-PA levels appear to differ between lacunar and cortical stroke subtypes, late after stroke, independent of age, sex and vascular risk factors and may reflect endothelial dysfunction. Except for a minor additional predictive effect of inflammatory markers, plasma biomarkers do not relate to WMH severity in this small stroke population. © 2015 S. Karger AG, Basel.
    Cerebrovascular Diseases 08/2015; 40(3-4):157-164. DOI:10.1159/000438494 · 3.70 Impact Factor
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    ABSTRACT: Anxiety is common and persistent after stroke, and is associated with a poorer quality of life. Guidelines from numerous countries, including the United Kingdom, recommend screening for poststroke emotional problems. Anxiety is a priority for the National Institute for Health and Care Excellence, stroke charities, and stroke survivors in the United Kingdom. Yet there is little evidence to guide the management of anxiety after stroke. New evidence-based interventions are needed to improve the care of poststroke anxiety. © 2015 World Stroke Organization.
    International Journal of Stroke 07/2015; 10(5):655-656. DOI:10.1111/ijs.12493 · 4.03 Impact Factor
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    ABSTRACT: Patients with TIA have high risk of recurrent stroke and require rapid assessment and treatment. The ABCD2 clinical risk prediction score is recommended for patient triage by stroke risk, but its ability to stratify by known risk factors and effect on clinic workload are unknown. We performed a systematic review and meta-analysis of all studies published between January 2005 and September 2014 that reported proportions of true TIA/minor stroke or mimics, risk factors, and recurrent stroke rates, dichotomized to ABCD2 score </≥4. We calculated the effect per 1,000 patients triaged on stroke prevention services. Twenty-nine studies, 13,766 TIA patients (range 69-1,679), were relevant: 48% calculated the ABCD2 score retrospectively; few reported on the ABCD2 score's ability to identify TIA mimics or use by nonspecialists. Meta-analysis showed that ABCD2 ≥4 was sensitive (86.7%, 95% confidence interval [CI] 81.4%-90.7%) but not specific (35.4%, 95% CI 33.3%-37.6%) for recurrent stroke within 7 days. Additionally, 20% of patients with ABCD2 <4 had >50% carotid stenosis or atrial fibrillation (AF); 35%-41% of TIA mimics, and 66% of true TIAs, had ABCD2 score ≥4. Among 1,000 patients attending stroke prevention services, including the 45% with mimics, 52% of patients would have an ABCD2 score ≥4. The ABCD2 score does not reliably discriminate those at low and high risk of early recurrent stroke, identify patients with carotid stenosis or AF needing urgent intervention, or streamline clinic workload. Stroke prevention services need adequate capacity for prompt specialist clinical assessment of all suspected TIA patients for correct patient management. © 2015 American Academy of Neurology.
    Neurology 07/2015; DOI:10.1212/WNL.0000000000001780 · 8.30 Impact Factor
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    ABSTRACT: Background Acute lacunar ischaemic stroke, white matter hyperintensities, and lacunes are all features of cerebral small vessel disease. It is unclear why some small vessel disease lesions present with acute stroke symptoms, whereas others typically do not.AimTo test if lesion location could be one reason why some small vessel disease lesions present with acute stroke, whereas others accumulate covertly.Methods We identified prospectively patients who presented with acute lacunar stroke symptoms with a recent small subcortical infarct confirmed on magnetic resonance diffusion imaging. We compared the distribution of the acute infarcts with that of white matter hyperintensity and lacunes using computational image mapping methods.ResultsIn 188 patients, mean age 67 ± standard deviation 12 years, the lesions that presented with acute lacunar ischaemic stroke were located in or near the main motor and sensory tracts in (descending order): posterior limb of the internal capsule (probability density 0·2/mm3), centrum semiovale (probability density = 0·15/mm3), medial lentiform nucleus/lateral thalamus (probability density = 0·09/mm3), and pons (probability density = 0·02/mm3). Most lacunes were in the lentiform nucleus (probability density = 0·01–0·04/mm3) or external capsule (probability density = 0·05/mm3). Most white matter hyperintensities were in centrum semiovale (except for the area affected by the acute symptomatic infarcts), external capsules, basal ganglia, and brainstem, with little overlap with the acute symptomatic infarcts (analysis of variance, P < 0·01).Conclusions Lesions that present with acute lacunar ischaemic stroke symptoms may be more likely noticed by the patient through affecting the main motor and sensory tracts, whereas white matter hyperintensity and asymptomatic lacunes mainly affect other areas. Brain location could at least partly explain the symptomatic vs. covert development of small vessel disease.
    International Journal of Stroke 06/2015; DOI:10.1111/ijs.12558 · 4.03 Impact Factor
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    ABSTRACT: Objective The aim of this study was to examine the practicality and accuracy of using an electronic monitoring device as a means of measuring medication adherence in elderly stroke survivors, with emphasis on patients’ experiences. Methods The Medication Event Monitoring System (MEMS), which records date and time of pill-bottle openings, was used to measure adherence to antihypertensive medication in a randomized controlled trial (RCT) of a brief psychological intervention with 58 stroke survivors. Patients were asked to describe and rate their experiences of using the MEMS pill bottle. Results MEMS adherence was related to both pill count and self-reported adherence (Medication Adherence Report Scale). Most patients found the MEMS acceptable and easy to use, although some found it cumbersome and/or experienced difficulties with the cap. Nearly half (48 %) reported at least one instance where MEMS data did not reflect their pill-taking behavior (e.g. taking a tablet out the day before to take on a flight); 55 % of patients indicated that the MEMS helped them remember their medication, suggesting a mere measurement effect. Conclusion Electronic pill monitoring has many flaws, including practical difficulties and data inaccuracies. There was evidence of a measurement effect, indicating that MEMS should be used in both intervention and control arms when used to measure adherence within RCTs. We also observed that the MEMS pill bottle is not suitable for measuring adherence in patients who use their own ‘days of the week’ box for sorting medication, as we found poorer adherence at follow-up in this group. Despite these limitations, we conclude that electronic monitoring presents the best method currently available for objective measurement of adherence, especially where detailed timing information is required. Accuracy may be improved by the concurrent use of other measures (e.g. pill count, self-report).
    Drugs & Therapy Perspectives 05/2015; 31:167-174. DOI:10.1007/s40267-015-0200-6
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    ABSTRACT: Dietary salt intake and hypertension are associated with increased risk of cardiovascular disease including stroke. We aimed to explore the influence of these factors, together with plasma sodium concentration, in cerebral small vessel disease (SVD). In all, 264 patients with nondisabling cortical or lacunar stroke were recruited. Patients were questioned about their salt intake and plasma sodium concentration was measured; brain tissue volume and white-matter hyperintensity (WMH) load were measured using structural magnetic resonance imaging (MRI) while diffusion tensor MRI and dynamic contrast-enhanced MRI were acquired to assess underlying tissue integrity. An index of added salt intake (P=0.021), pulse pressure (P=0.036), and diagnosis of hypertension (P=0.0093) were positively associated with increased WMH, while plasma sodium concentration was associated with brain volume (P=0.019) but not with WMH volume. These results are consistent with previous findings that raised blood pressure is associated with WMH burden and raise the possibility of an independent role for dietary salt in the development of cerebral SVD.Journal of Cerebral Blood Flow & Metabolism advance online publication, 22 April 2015; doi:10.1038/jcbfm.2015.64.
    Journal of cerebral blood flow and metabolism: official journal of the International Society of Cerebral Blood Flow and Metabolism 04/2015; DOI:10.1038/jcbfm.2015.64 · 5.34 Impact Factor
  • ESOC, Glasgow; 04/2015
  • European Stroke Organisation Conference, Glasgow; 04/2015
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    ABSTRACT: Dysphagia is common after stroke, so feeding through a nasogastric (NG) tube may be necessary. These tubes are frequently dislodged, causing interruption to feeding and hydration, and potential aspiration of feed or fluids into the lungs. Interventions to prevent this may include taping tubes to the face; the application of hand mittens or bandaging patients' hands; inserting the NG tube into the nostril on the stroke-affected side; and nasal bridles. The aims of this survey were to investigate the management of NG feeding for stroke patients, including current tube confirmation and securing techniques, and associated nurse education. This was part of a three-phased sequential mixed-methods study. This paper reports on the second quantitative phase. A quantitative postal survey, based on initial qualitative findings, was sent to registered nurses (n=528) from the National Stroke Nurses Forum and Scottish Stroke Nurses Forum, in addition to registered nurses working on stroke units within the local health board. The overall response rate was 59% (n=314/528). Tape was the most commonly used method for securing tube position, followed by inserting the tube on the stroke-affected side. Hand mittens were used more frequently than the nasal bridle; bandaging hands was reported once. Taping was considered to be more acceptable and safer than hand mittens or the nasal bridle, but less effective. Training in inserting NG feeding tubes was received by 56% (n=176/314). Methods used for confirming tube position included aspiration and X-ray. Provision of training in confirmation techniques varied. This study shows that the management of NG feeding for dysphagic stroke patients requires standardisation, as does the education for nurses to ensure that this intervention is carried out safely, effectively and acceptably.
    British journal of nursing (Mark Allen Publishing) 03/2015; 24(6):319-25. DOI:10.12968/bjon.2015.24.6.319
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    ABSTRACT: The pathogenesis of poststroke fatigue is unclear. In this prospective study, we explored whether reduced physical activity might contribute to poststroke fatigue or be a consequence of it. Patients with a recent acute stroke were assessed at 1, 6, and 12 months with, Fatigue Assessment Scale (FAS), a fatigue case definition, Hospital Anxiety and Depression Score, sleepiness, quality of life, and accelerometry (ActivPAL). Bivariate analyses determined associations between fatigue and step count at each time point. Multiple linear regression tested whether 1-month step count independently predicted 6- and 12-month FAS. A total of 136 participants (mean age, 72 years; 64% men) attended ≥1 assessment. ActivPAL data were available for 84 (64%), 69 (66%), and 58 (64%) participants at 1, 6, and 12 months, respectively. At 6 and 12 months, a positive fatigue case definition was associated with lower daily step counts (P=0.014 and 0.013, respectively). At 1, 6, and 12 months, higher FAS (more fatigue) was associated with lower step count (P<0.001, 0.01, and 0.007), higher depression (P<0.001), anxiety scores (P<0.001) and sleepiness (P<0.001), and poorer quality of life (P<0.001). Lower daily step count (P<0.002 and 0.006) and greater anxiety (P<0.001 for both) at 1 month independently predicted higher FAS at 6 and 12 months. Lower step counts at 1 month independently predicted greater FAS for ≤12 months. Physical activity might be a therapeutic target for poststroke fatigue. © 2015 American Heart Association, Inc.
    Stroke 02/2015; 46(4). DOI:10.1161/STROKEAHA.114.008079 · 6.02 Impact Factor
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    ABSTRACT: Further research is needed to better identify the methods of evaluating processes and outcomes of stroke care. We investigated whether achieving 4 evidence-based components of a care bundle in a Scotland-wide population with ischemic stroke is associated with 30-day and 6-month outcomes. Using national datasets, we looked at the effect of 4 standards (stroke unit entry on calendar day of admission [day 0] or day following [day 1], aspirin on day 0 or day 1, scan on day 0, and swallow screen recorded on day 0) on mortality and discharge to usual residence, at 30 days and 6 months. Data were corrected for the validated 6 simple variables, admission year, and hospital-level random effects. A total of 36 055 patients were included. Achieving stroke unit admission, swallow screen, and aspirin standards were associated with reduced 30-day mortality (adjusted odds ratio [95% confidence interval]: 0.82 [0.75-0.90], 0.88 [0.77-0.99], and 0.39 [0.35-0.43], respectively). Thirty-day all-cause mortality was higher when fewer standards were achieved, from 0 versus 4 (adjusted odds ratio [95% confidence interval], 2.95 [1.91-4.55]) to 3 versus 4 (adjusted odds ratio [95% confidence interval], 1.21 [1.09-1.34]). This effect persisted at 6 months. When less than the full care bundle was achieved, discharge to usual residence was less likely at 6 months (3 versus 4 standards; adjusted odds ratio [95% confidence interval], 0.91 [0.85-0.98]). Achieving a care bundle for ischemic stroke is associated with reduced mortality at 30 days and 6 months and increased likelihood of discharge to usual residence at 6 months. © 2015 American Heart Association, Inc.
    Stroke 02/2015; 46(4). DOI:10.1161/STROKEAHA.114.007608 · 6.02 Impact Factor
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    ABSTRACT: Several small trials have suggested that fluoxetine improves neurological recovery from stroke. FOCUS, AFFINITY and EFFECTS are a family of investigator-led, multicentre, parallel group, randomised, placebo-controlled trials that aim to determine whether routine administration of fluoxetine (20 mg daily) for 6 months after acute stroke improves patients' functional outcome. The three trial investigator teams have collaboratively developed a core protocol. Minor variations have been tailored to the national setting in the UK (FOCUS), Australia and New Zealand (AFFINITY) and Sweden (EFFECTS). Each trial is run and funded independently and will report its own results. A prospectively planned individual patient data meta-analysis of all three trials will subsequently provide the most precise estimate of the overall effect of fluoxetine after stroke and establish whether any effects differ between trials and subgroups of patients. The trials include patients ≥18 years old with a clinical diagnosis of stroke, persisting focal neurological deficits at randomisation between 2 and 15 days after stroke onset. Patients are randomised centrally via web-based randomisation systems using a common minimisation algorithm. Patients are allocated fluoxetine 20 mg once daily or matching placebo capsules for 6 months. Our primary outcome measure is the modified Rankin scale (mRS) at 6 months. Secondary outcomes include the Stroke Impact Scale, EuroQol (EQ5D-5 L), the vitality subscale of the Short-Form 36, diagnosis of depression, adherence to medication, adverse events and resource use. Outcomes are collected at 6 and 12 months. The methods of collecting these data are tailored to the national setting. If FOCUS, AFFINITY and EFFECTS combined enrol 6000 participants as planned, they would have 90 % power (alpha 5 %) to detect a common odds ratio of 1.16, equivalent to a 3.7 % absolute difference in percentage with mRS 0-2 (44.0 % to 47.7 %). This is based on an ordinal analysis of mRS adjusted for baseline variables included in the minimisation algorithm. If fluoxetine is safe and effective in promoting functional recovery, it could be rapidly, widely and affordably implemented in routine clinical practice and reduce the burden of disability due to stroke. ISRCTN83290762 (23/05/2012), AFFINITY: ACTRN12611000774921 (22/07/2011). ISRCTN13020412 (19/12/2014).
    Trials 01/2015; 16(1):369. DOI:10.1186/s13063-015-0864-1 · 2.12 Impact Factor
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    ABSTRACT: We compared compliance with standards of acute stroke care between 6 European audits and identified factors associated with delivery of appropriate care. Data were derived from stroke audits in Germany, Poland, Scotland, Catalonia, Sweden, and England/Wales/Northern-Ireland participating within the European Implementation Score (EIS) collaboration. Associations between demographic and clinical characteristics with adherence to predefined quality indicators were investigated by hierarchical logistic regression analyses. In 2007/2008 data from 329 122 patients with stroke were documented. Substantial variations in adherence to quality indicators were found; older age was associated with a lower probability of receiving thrombolytic therapy, anticoagulant therapy, or stroke unit treatment and a higher probability of being tested for dysphagia. Women were less likely to receive anticoagulant or antiplatelet therapy or stroke unit treatment. No major weekend effect was found. Detected variations in performance of acute stroke services were found. Differences in adherence to quality indicators might indicate population subgroups with specific needs for improving care delivery. © 2014 American Heart Association, Inc.
    Stroke 12/2014; 46(2). DOI:10.1161/STROKEAHA.114.007504 · 6.02 Impact Factor
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    Stephen D J Makin · F A B Cook · Martin S Dennis · Joanna M Wardlaw
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    ABSTRACT: Background The small vessel disease (SVD) that appears in the brain may be part of a multisystem disorder affecting other vascular beds such as the kidney and retina. Because renal failure is associated with both stroke and white matter hyperintensities we hypothesised that small vessel (lacunar) stroke would be more strongly associated with renal failure than cortical stroke. Therefore, we performed a systematic review and meta-analysis to establish first if lacunar stroke was associated with the renal function, and second, if cerebral small vessel disease seen on the MRI of patients without stroke was more common in patients with renal failure. Methods We searched Medline and EMBASE for studies in adults with cerebral SVD (lacunar stroke or white matter hyper intensities (WMH) on Magnetic Resonance Imaging (MRI)), in which renal function was assessed (estimated glomerular filtration rate (eGFR) or proteinuria). We extracted data on SVD diagnosis, renal function, demographics and comorbidities. We performed two meta-analyses: first, we calculated the odds of renal impairment in lacunar (small vessel) ischaemic stroke compared to other ischaemic stroke subtypes (non-small vessel disease); and second, we calculated the odds of renal impairment in non-stroke individuals with WMH on MRI compared to individuals without WMH. We then performed a sensitivity analysis by excluding studies with certain characteristics and repeating the meta-analysis calculation. Results After screening 11,001 potentially suitable titles, we included 37 papers reporting 32 studies of 20,379 subjects: 15 of stroke patients and 17 of SVD features in non-stroke patients. To diagnose lacunar stroke, 13/15 of the studies used risk factor-based classification (none used diffusion-weighted MRI). 394/1,119 (35%) of patients with lacunar stroke had renal impairment compared with 1,443/4,217 (34%) of patients with non-lacunar stroke, OR 0.88, (95% CI 0.6-1.30). In individuals without stroke the presence of SVD was associated with an increased risk of renal impairment (whether proteinuria or reduced eGFR) OR 2.33 (95% CI 1.80-3.01), when compared to those without SVD. After adjustment for age and hypertension, 15/21 studies still reported a significant association between renal impairment and SVD. Conclusion We found no specific association between renal impairment and lacunar stroke, but we did find that in individuals who had not had a stroke, having more SVD features on imaging was associated with a worse renal function, which remained significant after controlling for hypertension. However, this finding does not exclude a powerful co-associate effect of age or vascular risk factor exposure. Future research should subtype lacunar stroke sensitively and control for major risk factors.
    Cerebrovascular Diseases 12/2014; 39(1):39-52. DOI:10.1159/000369777 · 3.70 Impact Factor
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    ABSTRACT: Background To determine whether the predictions of functional outcome after ischemic stroke made at the bedside using a doctor’s clinical experience were more or less accurate than the predictions made by clinical prediction models (CPMs). Methods and Findings A prospective cohort study of nine hundred and thirty one ischemic stroke patients recruited consecutively at the outpatient, inpatient and emergency departments of the Western General Hospital, Edinburgh between 2002 and 2005. Doctors made informal predictions of six month functional outcome on the Oxford Handicap Scale (OHS). Patients were followed up at six months with a validated postal questionnaire. For each patient we calculated the absolute predicted risk of death or dependence (OHS≥3) using five previously described CPMs. The specificity of a doctor’s informal predictions of OHS≥3 at six months was good 0.96 (95% CI: 0.94 to 0.97) and similar to CPMs (range 0.94 to 0.96); however the sensitivity of both informal clinical predictions 0.44 (95% CI: 0.39 to 0.49) and clinical prediction models (range 0.38 to 0.45) was poor. The prediction of the level of disability after stroke was similar for informal clinical predictions (ordinal c-statistic 0.74 with 95% CI 0.72 to 0.76) and CPMs (range 0.69 to 0.75). No patient or clinician characteristic affected the accuracy of informal predictions, though predictions were more accurate in outpatients. Conclusions CPMs are at least as good as informal clinical predictions in discriminating between good and bad functional outcome after ischemic stroke. The place of these models in clinical practice has yet to be determined.
    PLoS ONE 10/2014; 9(10):e110189. DOI:10.1371/journal.pone.0110189 · 3.23 Impact Factor
  • Rustam Al-Shahi Salman · Martin S Dennis
    Stroke 09/2014; 45(10). DOI:10.1161/STROKEAHA.114.005786 · 6.02 Impact Factor
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    ABSTRACT: Objectives: In this cross-sectional study, we tested the construct validity of a “total SVD score,” which combines individual MRI features of small-vessel disease (SVD) in one measure, by testing associations with vascular risk factors and stroke subtype. Methods: We analyzed data from patients with lacunar or nondisabling cortical stroke from 2 prospective stroke studies. Brain MRI was rated for the presence of lacunes, white matter hyperintensities, cerebral microbleeds, and perivascular spaces independently. The presence of each SVD feature was summed in an ordinal “SVD score” (range 0–4). We tested associations with vascular risk factors, stroke subtype, and cerebral atrophy using ordinal regression analysis. Results: In 461 patients, multivariable analysis found that age (odds ratio [OR] 1.10, 95% confidence interval [CI] 1.08–1.12), male sex (OR 1.58, 95% CI 1.10–2.29), hypertension (OR 1.50, 95% CI 1.02–2.20), smoking (OR 2.81, 95% CI 1.59–3.63), and lacunar stroke subtype (OR 2.45, 95% CI 1.70–3.54) were significantly and independently associated with the total SVD score. The score was not associated with cerebral atrophy. Conclusions: The total SVD score may provide a more complete estimate of the full impact of SVD on the brain, in a simple and pragmatic way. It could have potential for patient or risk stratification or early efficacy assessment in clinical trials of interventions to prevent SVD progression and may (after further testing) have a useful role in clinical practice.
    Neurology 08/2014; 83(14). DOI:10.1212/WNL.0000000000000837 · 8.30 Impact Factor

Publication Stats

10k Citations
2,267.84 Total Impact Points

Institutions

  • 2001–2015
    • University of Aberdeen
      Aberdeen, Scotland, United Kingdom
  • 1994–2015
    • The University of Edinburgh
      • • Division of Clinical Neurosciences
      • • Department of Geriatric Medicine
      Edinburgh, Scotland, United Kingdom
  • 1991–2014
    • Western General Hospital
      Edinburgh, Scotland, United Kingdom
  • 2012
    • King's College London
      • Division of Health and Social Care Research
      Londinium, England, United Kingdom
  • 2010
    • Università degli Studi di Trieste
      Trst, Friuli Venezia Giulia, Italy
  • 2008
    • The Bracton Centre, Oxleas NHS Trust
      Дартфорде, England, United Kingdom
  • 2007
    • Edinburgh Napier University
      • School of Nursing, Midwifery & Social Care
      Edinburgh, Scotland, United Kingdom
  • 2006
    • Royal Melbourne Hospital
      Melbourne, Victoria, Australia
  • 1993
    • Royal Perth Hospital
      Perth City, Western Australia, Australia
  • 1990
    • University of Oxford
      • Nuffield Department of Clinical Neurosciences
      Oxford, England, United Kingdom