T S Olsen

Copenhagen University Hospital Hvidovre, Hvidovre, Capital Region, Denmark

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Publications (107)502.09 Total impact

  • T. S. Olsen, K. K. Andersen
    Journal of The Neurological Sciences - J NEUROL SCI. 01/2009; 285.
  • K. K. Andersen, T. S. Olsen
    Journal of The Neurological Sciences - J NEUROL SCI. 01/2009; 285.
  • K. K. Andersen, T. S. Olsen
    Journal of The Neurological Sciences - J NEUROL SCI. 01/2009; 285.
  • K. K. Andersen, T. S. Olsen
    Journal of The Neurological Sciences - J NEUROL SCI. 01/2009; 285.
  • T. S. Olsen, K. K. Andersen
    Journal of The Neurological Sciences - J NEUROL SCI. 01/2009; 285.
  • Stroke 01/2008; 39(3). · 6.16 Impact Factor
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    ABSTRACT: The very old are expected to become a growing part of the stroke population in the industrialised part of the world. The aims of this study were to evaluate clinical characteristics of patients aged 85 years or more at stroke onset and to investigate very old age as an independent predictor of short- and long-term outcome. In the community-based Copenhagen Stroke Study we recorded admission clinical characteristics in 1197 consecutive stroke patients. Patients were stratified according to age groups on admission. Follow-up was performed at a mean of 7 years after stroke onset. By way of multiple logistic regression and survival analyses very old age was independently related to short- and long-term mortality and nursing home placement independent of other clinical characteristics. 16% of patients were 85 years or older at the time of stroke onset. More of the very old were women (75% versus 50%, P<0.0001), living alone (84% versus 54%, P<0.0001), had atrial fibrillation (37% versus 15%, P<0.0001), had pre-existing disability (29% versus 22%, P = 0.04), and had more severe strokes (Scandinavian Stroke Scale score 31 versus 37 points, P = 0.004). Fewer very old had hypertension (25% versus 34%, P = 0.02) and diabetes (14% versus 22%, P = 0.01). In adjusted multiple regression models, very old age predicted short-term mortality (OR 2.5; 95% CI 1.5-4.2), and discharge to nursing home or in-hospital mortality (OR 2.7; 95% CI 1.7-4.4). Five years after stroke very old age predicted mortality or nursing home placement (OR 3.9; 95% CI 2.1-7.3), and long-term mortality (HR 2.0; 95% CI 1.6-2.5). However, other factors such as onset stroke severity, pre-existing disability and atrial fibrillation were also significant independent predictors of prognosis after stroke. In this study very old age per se was a strong predictor of outcome and mortality after stroke. Apart from very old age, factors such as prestroke medical and functional status, and onset stroke severity should be taken into consideration when planning treatment and rehabilitation after stroke.
    Age and Ageing 04/2004; 33(2):149-54. · 3.82 Impact Factor
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    ABSTRACT: Body temperature is considered crucial in the management of acute stroke patients. Recently hypothermia applied as a therapy for stroke has been demonstrated to be feasible and safe in acute stroke patients. In the present study, we investigated the predictive role of admission body temperature to the long-term mortality in stroke patients. We studied 390 patients with acute stroke admitted within 6 hours from stroke onset. Admission clinical characteristics (age, sex, admission stroke severity, admission blood glucose, cardiovascular risk factor profile, and stroke subtype) were recorded for patients with hypothermia (body temperature < or =37 degrees C) versus patients with hyperthermia (body temperature >37 degrees C). Univariately the mortality rates for all patients were studied by Kaplan-Meier statistics. To find independent predictors of long-term mortality for all patients, Cox proportional-hazards models were built. We included all clinical characteristics and body temperature as a continuous variable. Patients with hyperthermia had more severe strokes and more frequently diabetes, whereas no difference was found for the other clinical characteristics. For all patients mortality rate at 60 months after stroke was higher for patients with hyperthermia (73 per 100 cases versus 59 per 10 cases, P=0.001). When body temperature was studied in a multivariate Cox proportional-hazards model, a 1 degrees C increase of admission body temperature independently predicted a 30% relative increase (95% CI, 4% to 57%) in long-term mortality risk. For 3-month survivors we found no association between body temperature and long-term survival when studied in a multivariate Cox proportional hazard model (hazards ratio, 1.11 per 1 degrees C; 95% CI, 0.82 to 1.52). Low body temperature on admission is considered to be an independent predictor of good short-term outcome. The present study suggests that admission body temperature seems to be a major determinant even for long-term mortality after stroke. Hypothermic therapy in the early stage in which body temperature is kept low for a longer period after ictus could be a long-lasting neuroprotective measure.
    Stroke 07/2002; 33(7):1759-62. · 6.16 Impact Factor
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    ABSTRACT: This study examines blood pressure (BP) and independent factors related to BP in the acute phase of stroke. The study is part of the community-based Copenhagen Stroke Study. In a multivariate regression model we analyzed the impact of clinical and medical factors on admission BP. BP declined with increasing time from stroke onset with a total of 8/4 mm Hg. Independent factors related to diastolic BP were ischemic heart disease (-3.9 mm Hg), male gender (2.2 mm Hg), known hypertension prior to stroke (8.6 mm Hg), and primary hemorrhage (9.7 mm Hg). Independent factors related to systolic BP were age (3.6 mm Hg/10-year increase), atrial fibrillation (-7.2 mm Hg), ischemic heart disease (-6.0 mm Hg), intracerebral hemorrhage (13.3 mm Hg), and known hypertension prior to stroke (16.3 mm Hg). No independent relations were seen between BP and diabetes, claudication, previous stroke, smoking, daily alcohol consumption, initial stroke severity and lesion size. The increase in BP in the acute phase of stroke is a uniform response to the ischemic event per se. BP is not related to stroke severity. Several factors are independently related to the BP level in acute stroke. The clinical significance of this is yet to be tested, but these factors may contribute to the seemingly complex relation between BP and outcome.
    Cerebrovascular Diseases 02/2002; 13(3):204-9. · 2.81 Impact Factor
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    ABSTRACT: To estimate the need for and the costs of carotid Doppler and carotid endarterectomy after stroke or TIA in non-selected hospitalized patients. During 25 months hospitalized patients with stroke or TIA, in whom carotid endarterectomy could be relevant, were examined with carotid Doppler. If a significant stenosis was found, they were further evaluated for surgery. Based on our results, the requirement for future carotid endarterectomy and Doppler screening was estimated, and the costs of the procedures calculated. Among 1351 patients 703 were screened with carotid Doppler. Forty-five had severe (70-99%) stenosis of the relevant carotid artery. Only 3 were operated on. The future costs of screening were estimated under different assumptions. Carotid endarterectomy is expensive due to the large number of patients screened with carotid Doppler per operated patient. A careful clinical selection of patients for screening is necessary.
    Acta Neurologica Scandinavica 02/2002; 105(1):1-4. · 2.47 Impact Factor
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    ABSTRACT: To determine the frequency of manual and oral apraxia in acute stroke and to examine the influence of these symptoms on functional outcome. Seven hundred seventy six unselected, acute stroke patients who were admitted within seven days of stroke onset with unimpaired consciousness were included. If possible, the patients were assessed for manual and oral apraxia on acute admission. Neurologic stroke severity including aphasia was assessed with the Scandinavian Stroke Scale, and activities of daily living function was assessed with the Barthel Index. All patients completed their rehabilitation in the same large stroke unit. Six hundred eighteen patients could cooperate with the apraxia assessments. Manual apraxia was found in 7% of subjects (10% in left and 4% in right hemispheric stroke; chi2 = 9.0; P = 0.003). Oral apraxia was found in 6% (9% in left and 4% in right hemispheric stroke; chi2 = 5.4; P = 0.02). Both manual and oral apraxia were related to increasing stroke severity, and manual, but not oral, apraxia was associated with increasing age. There was no gender difference in frequency of apraxia. Patients with either type of apraxia had temporal lobe involvement more often than patients without. When analyzed with multiple linear and logistic regression analyses, neither manual nor oral apraxia had any independent influence on functional outcome. Apraxia is significantly less frequent in unselected patients with acute stroke than has previously been assumed and has no independent negative influence on functional outcome.
    American Journal of Physical Medicine & Rehabilitation 10/2001; 80(9):685-92. · 1.73 Impact Factor
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    ABSTRACT: Pedersen PM, J/orgensen HS, Kammersgaard LP, Nakayama H, Raaschou HO, Olsen TS: Manual and oral apraxia in acute stroke, frequency and influence on functional outcome: the Copenhagen Stroke Study. Am J Phys Med Rehabil 2001;80:685-692. Objectives: To determine the frequency of manual and oral apraxia in acute stroke and to examine the influence of these symptoms on functional outcome. Design: Seven hundred seventy six unselected, acute stroke patients who were admitted within seven days of stroke onset with unimpaired consciousness were included. If possible, the patients were assessed for manual and oral apraxia on acute admission. Neurologic stroke severity including aphasia was assessed with the Scandinavian Stroke Scale, and activities of daily living function was assessed with the Barthel Index. All patients completed their rehabilitation in the same large stroke unit. Results: Six hundred eighteen patients could cooperate with the apraxia assessments. Manual apraxia was found in 7% of subjects (10% in left and 4% in right hemispheric stroke; χ2= 9.0;P = 0.003). Oral apraxia was found in 6% (9% in left and 4% in right hemispheric stroke; χ2= 5.4;P = 0.02). Both manual and oral apraxia were related to increasing stroke severity, and manual, but not oral, apraxia was associated with increasing age. There was no gender difference in frequency of apraxia. Patients with either type of apraxia had temporal lobe involvement more often than patients without. When analyzed with multiple linear and logistic regression analyses, neither manual nor oral apraxia had any independent influence on functional outcome. Conclusion: Apraxia is significantly less frequent in unselected patients with acute stroke than has previously been assumed and has no independent negative influence on functional outcome.
    American Journal of Physical Medicine & Rehabilitation 08/2001; 80(9):685-692. · 1.73 Impact Factor
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    ABSTRACT: Infection is a frequent complication in the early course of acute stroke and may adversely affect stroke outcome. In the present study, we investigate early infection developing in patients within 3 days of admission to the hospital and its independent relation to recovery and stroke outcome. In addition, we identify predictors for early infections, infection subtypes, and their relation to initial stroke severity. In the community-based Copenhagen Stroke Study, 1,156 unselected patients were examined for early infection. Stroke severity was assessed with the Scandinavian Stroke Scale (SSS) on admission and at discharge. Multiple logistic and linear regression analyses were used to determine independent relations to early infection. Relevant stroke risk factors, admission stroke severity, and body temperature were included in the analysis. Of the subjects studied, 19.4% developed early infection. In women, 68% of the early infections were urinary tract infections, and in men, 49% of the early infections were pneumonias. Independent predictors of early infection were advanced age (OR per 10 years, 1.24; 95% CI, 1.02-1.64), female gender (OR, 2.0; 95% CI, 1.3-3.0), and decreased SSS score on admission (OR per 10 points, 0.69; 95% CI, 0.62-0.78). The presence of early infection prolonged hospital stay by a mean of 9.3 days (P < .0001) but not death during hospital stay (P = .78), stroke severity at discharge (P = .32), or rate of discharge to nursing home (P = .17). Advanced age, female gender, and increased stroke severity independently predict development of early infection. The present study indicates that early infection does not influence outcome in acute stroke patients per se, but it delays patient discharge from the hospital.
    Journal of stroke and cerebrovascular diseases: the official journal of National Stroke Association 01/2001; 10(5):217-21.
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    ABSTRACT: In the Copenhagen Stroke Study, we evaluated the combined impact on stroke outcome of potentially treatable factors such as acute body temperature, blood glucose, and stroke in progression. The patients were stratified into two groups: (1) patients with 'good' prognostic parameters (body temperature on admission < or = 37.0 degrees C and plasma glucose on admission < or = 6.5 mmol/l and who did not develop stroke in progression) and (2) patients with correspondingly 'poor' prognostic parameters. A poor outcome was observed in 4% of the patients with good prognostic parameters versus in 49% of the patients with poor prognostic parameters (p < 0.01). In the multivariate analysis which also included stroke severity, blood glucose contributed significantly to poor outcome with an odds ratio (OR) of 1.2/1.0 mmol/l increase, body temperature with an OR of 2.2/1 degrees C increase, and stroke in progression with an OR of 2.9. However, the combined effect of all three factors was more than additive with an OR of 10.0 (95% CI 1.5-56; p < 0.01). We have shown that in human stroke a strong and more than additive association exists between potentially reversible parameters and outcome. Intervention trials can prove whether these marked relations are causal.
    Cerebrovascular Diseases 01/2001; 11(3):207-11. · 2.81 Impact Factor
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    ABSTRACT: Hypothermia reduces neuronal damage in animal stroke models. Whether hypothermia is neuroprotective in patients with acute stroke remains to be clarified. In this case-control study, we evaluated the feasibility and safety of inducing modest hypothermia by a surface cooling method in awake patients with acute stroke. We prospectively included 17 patients (cases) with stroke admitted within 12 hours from stoke onset (mean 3.25 hours). They were given hypothermic treatment for 6 hours by the "forced air" method, a surface cooling method that uses a cooling blanket with a flow of cool air (10 degrees C). Pethidine was given to treat compensatory shivering. Cases were compared with 56 patients (controls) from the Copenhagen Stroke Study matched for age, gender, initial stroke severity, body temperature on admission, and time from stroke onset to admission. Blood cytology, biochemistry, ECGs, and body temperature were monitored during hypothermic treatment. Multiple regression analyses on outcome were performed to examine the safety of hypothermic therapy. Body temperature decreased from t(0)=36.8 degrees C to t(6)=35.5 degrees C (P:<0.001), and hypothermia was present until 4 hours after therapy (t(0)=36.8 degrees C versus t(10)=36.5 degrees C; P:=0.01). Mortality at 6 months after stroke was 12% in cases versus 23% in controls (P:=0. 50). Final neurological impairment (Scandinavian Stroke Scale score at 6 months) was mean 42.4 points in cases versus 47.9 in controls (P:=0.21). Hypothermic therapy was not a predictor of poor outcome in the multivariate analyses. Modest hypothermia can be achieved in awake patients with acute stroke by surface cooling with the "forced air" method, in combination with pethidine to treat shivering. It was not associated with a poor outcome. We suggest a large, randomized clinical trial to test the possible beneficial effect of induced modest hypothermia in unselected patients with stroke.
    Stroke 10/2000; 31(9):2251-6. · 6.16 Impact Factor
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    ABSTRACT: Treatment of stroke patients in specialised stroke units has become more frequent, but the longterm effect of this treatment has not been determined. In this prospective, community-based study of 1241 unselected acute stroke patients we compared outcome between patients geographically randomised to treatment in a stroke unit or in a general neurological/medical ward, from the time of acute admission to the end of rehabilitation. Baseline characteristics were comparable between the two treatment groups regarding age, sex, marital status, pre-stroke residence, and stroke severity. Patients treated in the stroke unit had higher comorbidity with regard to hypertension and diabetes. Multivariate linear and logistic regression analyses were applied to estimate the independent influence of stroke unit treatment on outcome. Stroke unit treatment significantly reduced not only initial mortality, but also mortality within five years from stroke onset. The relative risk of dying within the first five years from stroke was reduced by 40%, p < 0.01. Treatment and rehabilitation of unselected stroke patients in a stroke unit reduces initial mortality, discharge rate to nursing home, reduces cost of treatment, and improves longterm survival up to five years after stroke.
    Ugeskrift for laeger 07/2000; 162(24):3450-2.
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    ABSTRACT: The majority of stroke patients with initial leg paralysis do not regain independent walking. We characterize the minority who, despite initial leg paralysis, regained independent walking. Consecutive and community based. A stroke unit receiving all stroke patients from a well-defined community. A total of 859 acute stroke patients; 157 (15%) initially had leg paralysis. Scandinavian Stroke Scale (SSS) and Barthel index (BI) on admission and weekly during rehabilitation. Univariate and multivariate statistics were considered. Of the 157 patients with initial leg paralysis, 84 (60%) died; 73 (40%) survived. Fifteen (21%) survivors regained walking function (the walking group), and 58 (79%) did not (the nonwalking group). The BI on admission was the only factor of significant predictive value (p < .03). Mean admission BI was 50 in the walking group versus 3 in the nonwalking group (p < .001). Age, gender, lesion size, total SSS score, and comorbidity had no predictive value. Within the first week, the walking group gained 3.2 points in the SSS subscore for leg strength versus 0.5 points in the nonwalking group (p < .02). Only 10% of stroke patients with initial leg paralysis regained independent walking. In these patients, BI on admission was high and leg strength improved quickly in the first week.
    Archives of Physical Medicine and Rehabilitation 06/2000; 81(6):736-8. · 2.36 Impact Factor
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    ABSTRACT: The beneficial effects of treatment and rehabilitation of patients with acute stroke in a dedicated stroke unit (SU) are well established. We wanted to examine if these effects are limited to certain groups of patients or if they apply to all patients independent of age, sex, comorbidity, and initial stroke severity. This was a community-based study of outcome in 1241 consecutive stroke patients from 2 communities in Copenhagen: In one (Frederiksberg), treatment and rehabilitation were given in general neurological and medical wards (GW), and in the other (Bispebjerg) in one single large SU. Outcome measures were initial, 1-year, and 5-year mortality rates, a poor outcome (initial death or discharge to a nursing home), and length of hospital stay (LOHS). Multivariate regression analyses were used to examine the independent effect of SU treatment on the various subgroups. The relative risks of initial death, poor outcome, and 1-year and 5-year mortality rates were reduced by 40% on average in patients treated in the SU compared with the GW. A beneficial effect of SU treatment was observed regardless of the patient's age, sex, comorbidity, and initial stroke severity. Those who benefited most appeared to be the patients with the most severe strokes (poor outcome: OR 0.17; 95% CI 0.05 to 0.58). Those who benefited least were patients with mild or moderate strokes (poor outcome: OR 0.66; 95% CI 0.41 to 0.98) and patients <75 years of age (poor outcome: OR 0.66; 95% CI 0.36 to 1.19). LOHS was reduced by 2 to 3 weeks in all who had their treatment in the SU except in patients with the most severe strokes. LOHS in these patients was similar to LOHS in the GW. A beneficial effect of treatment in a SU is achieved in completely unselected patients independent of their age, sex, comorbidity, and stroke severity. Those who had the most severe strokes appeared to benefit most. All patients with acute stroke should therefore have access to treatment and rehabilitation in a dedicated SU.
    Stroke 02/2000; 31(2):434-9. · 6.16 Impact Factor
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    ABSTRACT: Neurologic and functional recovery is dependent on a large variety of factors such as initial stroke severity, body temperature and blood glucose in the acute phase of stroke, stroke in progression, and treatment and rehabilitation on a dedicated stroke unit. The most important factor for recovery remains the initial severity of the stroke. In unselected patients 19% of the strokes are very severe, 14% are severe, 26% are moderate, and 41% are mild. In survivors, neurologic impairment after completed rehabilitation is still severe or very severe in 11%, moderate in 11%, mild in 47%, and 31% have achieved normal neurologic function. The ability to perform basic activities of daily living initially is reduced in three out of four patients with stroke. Most often affected is the ability to transfer, dress, and walk. After completed rehabilitation the group with moderate and severe disability is reduced from 50% to 25%, and the group with mild or no disability is increased from 50% to 75%. The prognosis of patients with mild or moderate stroke generally is excellent. Patients with severe stroke have a very variable recovery. Although the prognosis of patients with the most severe stroke is generally poor, one third of the survivors in this group are able to be discharged back to their own homes with no or only mild disability, if rehabilitated on a dedicated stroke unit. Functional recovery generally was completed within 3 months of stroke onset. Patients with mild stroke, however, recover within 2 months, patients with moderate stroke within 3 months, patients with severe stroke within 4 months, and patients with the most severe strokes have their functional recovery within 5 months from onset. Functional recovery is preceded by neurologic recovery by a mean of 2 weeks.
    Physical Medicine and Rehabilitation Clinics of North America 12/1999; 10(4):887-906. · 1.48 Impact Factor
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    ABSTRACT: This article describes basic characteristics and primary outcomes of unselected patients with stroke. These patients were part of the Copenhagen Stroke Study, a prospective, consecutive, and community-based study of 1197 acute stroke patients. The setting and care was multidisciplinary and all treatment was performed within the dedicated stroke unit. Neurologic impairment was measured at admission, weekly throughout the hospital stay, and again at the 6-month follow up. Basic activities of daily living, as measured by the Barthel Index, were assessed within the first week of admission, weekly throughout the hospital stay, and again after 6 months. Upon completion of the in-hospital rehabilitation, which averaged 37 days, two-thirds of surviving patients were discharged to their homes, with another 15% being discharged to a nursing home. Only 4% of the patients with very severe strokes reached independent function, as compared with 13% of patients with severe stroke, 37% of patients with moderate stroke, and 68% of patients with mild stroke.
    Clinics in Geriatric Medicine 12/1999; 15(4):785-99. · 3.14 Impact Factor

Publication Stats

5k Citations
502.09 Total Impact Points

Institutions

  • 1981–2004
    • Copenhagen University Hospital Hvidovre
      • Danish Research Centre for Magnetic Resonance
      Hvidovre, Capital Region, Denmark
  • 1991–2002
    • Copenhagen University Hospital Gentofte
      Hellebæk, Capital Region, Denmark
  • 1982–2002
    • Bispebjerg Hospital, Copenhagen University
      • • Department of Neurology
      • • Department of Clinical Physiology and Nuclear Medicine
      Copenhagen, Capital Region, Denmark
  • 1998
    • Glostrup Hospital
      • Department of Clinical Biochemistry
      København, Capital Region, Denmark