Plasminogen Activator Inhibitor-1 (PAI-1) 4G/5G Promoter Polymorphism and Levels in Subjects with Cerebrovascular Disease

The exact role of the fibrinolytic system in the pathogenesis of stroke remains to be established. Elevated circulating levels of plasminogen activator inhibitor-1, the principle inactivator of the fibrinolytic system, have been related to the development of myocardial infarction. There is evidence that a polymorphism in the promoter region of the PAI-1 gene is associated with circulating PAI-1 levels.

We studied a common single nucleotide insertion/deletion (4G/5G) polymorphism by PCR in 558 patients with stroke, the pathological type of which was established by cranial computed tomography, and in 172 controls. 4G/5G genotype and PAI-1 activity were investigated in relation to 1) stroke type and 2) mortality occurring within four weeks, three months and six months of the stroke.

No difference in genotype frequency was observed when all cases of stroke were compared with controls nor between the clinically determined subtypes of cerebral infarction. PAI-1 activity was significantly higher in patients with stroke (n = 245) both at presentation (11.6 U/ml) and after three months (11.8 U/ml), in paired samples, than in control subjects (8.8 U/ml, p <0.0001). Thirty-seven (6.2%), 86 (14.5%) and 122 (20.5%) patients had died within one, three and six months of admission, respectively. PAI-1 activity was independently associated with all-cause mortality at one and three months after stroke (p = 0.02 and p = 0.03 respectively), but not after six months.

In this population the 4G/5G promoter polymorphism is not associated with an increased risk of stroke. PAI-1 levels were elevated at the time of acute stroke which persisted after three months. PAI-1 level but not genotype was associated with early mortality following stroke.

Elevated C-reactive protein and long-term mortality after ischaemic stroke: relationship with markers of endothelial cell and platelet activation

BACKGROUND AND PURPOSE

Inflammatory biomarkers predict development of atherothrombotic events. In the present study we examined the relationships between C-reactive protein (CRP), complement C3, and long-term mortality after acute ischemic stroke.

METHODS

CRP and C3 were analyzed by in-house enzyme-linked immunosorbent assay in 394 subjects with acute ischemic stroke who survived for >30 days, followed-up for a median of 7.4 years.

RESULTS

CRP was higher in subjects who died (10.8 mg/L; 95% CI, 9.1-12.8) compared with survivors (3.8 mg/L; 95% CI, 3.1-4.7), whereas C3 was similar in both groups (P=0.26). CRP remained predictive for mortality after adjusting for conventional clinical and demographic risk factors (the adjusted hazard ratio for those with CRP in the highest compared with the lowest quartile was 2.0; 95% CI, 1.3-3.1). However, CRP was no longer independently predictive of mortality after additionally adjusting for beta-thromboglobulin or von Willebrand factor.

CONCLUSIONS

Our data suggest that the relationship between CRP and poststroke mortality may in part reflect inflammation-induced endothelial cell dysfunction and platelet activation.

Predictive Variables for Mortality After Acute Ischemic Stroke

Background and Purpose— Stroke is a major healthcare issue worldwide with an incidence comparable to coronary events, highlighting the importance of understanding risk factors for stroke and subsequent mortality.

Methods— In the present study, we determined long-term (all-cause) mortality in 545 patients with ischemic stroke compared with a cohort of 330 age-matched healthy control subjects followed up for a median of 7.4 years. We assessed the effect of selected demographic, clinical, biochemical, hematologic, and hemostatic factors on mortality in patients with ischemic stroke. Stroke subtype was classified according to the Oxfordshire Community Stroke Project criteria. Patients who died 30 days or less after the acute event (n=32) were excluded from analyses because this outcome is considered to be directly attributable to the acute event.

Results— Patients with ischemic stroke were at more than 3-fold increased risk of death compared with the age-matched control cohort. In multivariate analyses, age, stroke subtype, atrial fibrillation, and previous stroke/transient ischemic attack were predictive of mortality in patients with ischemic stroke. Albumin and creatinine and the hemostatic factors von Willebrand factor and β-thromboglobulin were also predictive of mortality in patients with ischemic stroke after accounting for demographic and clinical variables.

Conclusions— The results indicate that subjects with acute ischemic stroke are at increased risk of all-cause mortality. Advancing age, large-vessel stroke, atrial fibrillation, and previous stroke/transient ischemic attack predict mortality; and analysis of albumin, creatinine, von Willebrand factor, and β-thromboglobulin will aid in the identification of patients at increased risk of death after stroke.

Glucose-potassium-insulin infusions in the management of post-stroke hyperglycaemia: the UK Glucose Insulin in Stroke Trial (GIST-UK)

BACKGROUND

Hyperglycaemia after acute stroke is a common finding that has been associated with an increased risk of death. We sought to determine whether treatment with glucose-potassium-insulin (GKI) infusions to maintain euglycaemia immediately after the acute event reduces death at 90 days.

METHODS

Patients presenting within 24 h of stroke onset and with admission plasma glucose concentration between 6.0-17.0 mmol/L were randomly assigned to receive variable-dose-insulin GKI (intervention) or saline (control) as a continuous intravenous infusion for 24 h. The purpose of GKI infusion was to maintain capillary glucose at 4-7 mmol/L, with no glucose intervention in the control group. The primary outcome was death at 90 days, and the secondary endpoint was avoidance of death or severe disability at 90 days. Additional planned analyses were done to determine any differences in residual disability or neurological and functional recovery. The trial was powered to detect a mortality difference of 6% (sample size 2355), with 83% power, at the 5% two-sided significance level. This study is registered as an International Standard Randomised Controlled Trial (number ISRCTN 31118803)

FINDINGS

The trial was stopped due to slow enrolment after 933 patients were recruited. For the intention-to-treat data, there was no significant reduction in mortality at 90 days (GKI vs control: odds ratio 1.14, 95% CI 0.86-1.51, p=0.37). There were no significant differences for secondary outcomes. In the GKI group, overall mean plasma glucose and mean systolic blood pressure were significantly lower than in the control group (mean difference in glucose 0.57 mmol/L, p<0.001; mean difference in blood pressure 9.0 mmHg, p<0.0001).

INTERPRETATION

GKI infusions significantly reduced plasma glucose concentrations and blood pressure. Treatment within the trial protocol was not associated with significant clinical benefit, although the study was underpowered and alternative results cannot be excluded.

A patient with neuro-Behçet's disease is successfully treated with etanercept: Further evidence for the value of TNFα blockade

Behçet's disease is a chronic relapsing multisystem vasculitis with 49% of cases involving the CNS. Recently there have been two reports of neuro-Behçet's disease (NB) successfully treated with the tumour necrosis factor alpha (TNFalpha) monoclonal antibody infliximab. We describe a patient with longstanding NB who was poorly responsive to azathioprine, cyclosporin, thalidomide and methotrexate. She showed a remarkable response when treated with the recombinant human TNFalpha receptor protein, etanercept. To the best of our knowledge this is the first report of NB successfully treated with etanercept.

Change in stroke incidence, mortality, case-fatality, severity, and risk factors in Oxfordshire, UK from 1981 to 2004 (Oxford Vascular Study)

BACKGROUND

The incidence of stroke is predicted to rise because of the rapidly ageing population. However, over the past two decades, findings of randomised trials have identified several interventions that are effective in prevention of stroke. Reliable data on time-trends in stroke incidence, major risk factors, and use of preventive treatments in an ageing population are required to ascertain whether implementation of preventive strategies can offset the predicted rise in stroke incidence. We aimed to obtain these data.

METHODS

We ascertained changes in incidence of transient ischaemic attack and stroke, risk factors, and premorbid use of preventive treatments from 1981-84 (Oxford Community Stroke Project; OCSP) to 2002-04 (Oxford Vascular Study; OXVASC).

FINDINGS

Of 476 patients with transient ischaemic attacks or strokes in OXVASC, 262 strokes and 93 transient ischaemic attacks were incident events. Despite more complete case-ascertainment than in OCSP, age-adjusted and sex-adjusted incidence of first-ever stroke fell by 29% (relative incidence 0.71, 95% CI 0.61-0.83, p=0.0002). Incidence declined by more than 50% for primary intracerebral haemorrhage (0.47, 0.27-0.83, p=0.01) but was unchanged for subarachnoid haemorrhage (0.83, 0.44-1.57, p=0.57). Thus, although 28% more incident strokes (366 vs 286) were expected in OXVASC due to demographic change alone (33% increase in those aged 75 or older), the observed number fell (262 vs 286). Major reductions were recorded in mortality rates for incident stroke (0.63, 0.44-0.90, p=0.02) and in incidence of disabling or fatal stroke (0.60, 0.50-0.73, p<0.0001), but no change was seen in case-fatality due to incident stroke (17.2% vs 17.8%; age and sex adjusted relative risk 0.85, 95% CI 0.57-1.28, p=0.45). Comparison of premorbid risk factors revealed substantial reductions in the proportion of smokers, mean total cholesterol, and mean systolic and diastolic blood pressures and major increases in premorbid treatment with antiplatelet, lipid-lowering, and blood pressure lowering drugs (all p<0.0001).

INTERPRETATION

The age-specific incidence of major stroke in Oxfordshire has fallen by 40% over the past 20 years in association with increased use of preventive treatments and major reductions in premorbid risk factors.

Homocysteine is a risk factor for cerebral small vessel disease, acting via endothelial dysfunction

Cerebral small vessel disease (SVD) causes focal lacunar infarction and more diffuse ischaemia, referred to as leukoaraiosis. Endothelial dysfunction has been proposed as a causal mechanism in the disease. Homocysteine is toxic to endothelium. We determined whether elevated homocysteine levels and the methylene tetrahydrofolate reductase (MTHFR) C677T polymorphism are risk factors for SVD as a whole, and for two different SVD subtypes: isolated lacunar infarction and ischaemic leukoaraiosis. We also determined whether any association was mediated by endothelial dysfunction, as assessed by circulating endothelial markers. One hundred and seventy-two Caucasian patients with SVD and 172 community controls of similar age and sex were studied. Serum homocysteine measurement and MTHFR genotyping was performed. Levels of intercellular adhesion molecule 1 (ICAM1) and thrombomodulin were measured in a subgroup. Mean homocysteine levels were higher in SVD than controls [14.55 micromol/l [95% confidence interval (CI) 13.78-15.35] versus 12.01 micromol/l (95% CI 11.42-12.64), P < 0.0005]. Homocysteine was a stronger risk factor in those with ischaemic leukoaraiosis [12.92 (95% CI 4.40-37.98), P < 0.0005) per micromol increase in log homocysteine concentration (P < 0.0005)] in comparison with isolated lacunar infarction [4.22 (95% CI 1.29-13.73), P = 0.02] after controlling for both conventional risk factors and age. The MTHFR 677T allele was a risk factor only in the ischaemic leukoaraiosis group [odds ratio (OR) 2.02 (95% CI 1.31-3.1), P = 0.001]. Inclusion of the endothelial markers ICAM1 and thrombomodulin in a logistic regression model resulted in the association between homocysteine and SVD no longer being significant. In conclusion, hyperhomocysteinaemia is an independent risk factor for SVD, particularly ischaemic leukoaraiosis, and this effect may be mediated via endothelial dysfunction. Homocysteine-lowering therapy may be particularly effective in this subgroup.

Markers of endothelial dysfunction in lacunar infarction and ischaemic leukoaraiosis

Patients with cerebral small vessel disease (SVD) can present as isolated lacunar infarction or with diffuse white matter changes, with the imaging appearance of leukoaraiosis. Endothelial dysfunction, which can lead to breakdown of the blood-brain barrier, impaired cerebral autoregulation and prothrombotic changes, is believed to be important in mediating disease. Circulating levels of intercellular adhesion molecule 1 (ICAM1), thrombomodulin (TM), tissue factor (TF) and tissue factor pathway inhibitor (TFPI) are markers of endothelial activation and damage, and may provide insights into disease pathogenesis or differences between phenotypes. We therefore measured these markers in a prospective series of patients with lacunar stroke. One hundred and ten white Caucasian patients with previous lacunar stroke and 50 community control subjects were studied. Markers of endothelial function were measured on venous blood samples. Patients were classified on brain imaging into two groups: isolated lacunar infarction (n = 47) and ischaemic leukoaraiosis, defined as a clinical lacunar stroke and leukoaraiosis on brain imaging (n = 63). The number of lacunes and severity of leukoaraiosis were also scored on MRI. ICAM1, TM and TFPI were elevated in cerebral SVD subjects compared with controls (P <or= 0.006). The ischaemic leukoaraiosis group had a different endothelial marker profile, with lower levels of TFPI (P = 0.01) and a higher TF/TFPI ratio (P = 0.01) compared with the isolated lacunar infarction group. TM levels were associated with the number of lacunes (P = 0.008) and the leukoaraiosis score (P = 0.03), but TF levels and the TF/TFPI ratio were associated only with the extent of leukoaraiosis (P <or= 0.02). These results suggest that there is evidence of chronic endothelial dysfunction in cerebral SVD, and endothelial prothrombotic changes may be important in mediating the ischaemic leukoaraiosis phenotype. Therapies which help to stabilize the endothelium may have a role in this group of patients.

Markers of endothelial dysfunction in lacunar infarction and ischaemic leukoaraiosis

Patients with cerebral small vessel disease (SVD) can present as isolated lacunar infarction or with diffuse white matter changes, with the imaging appearance of leukoaraiosis. Endothelial dysfunction, which can lead to breakdown of the blood-brain barrier, impaired cerebral autoregulation and prothrombotic changes, is believed to be important in mediating disease. Circulating levels of intercellular adhesion molecule 1 (ICAM1), thrombomodulin (TM), tissue factor (TF) and tissue factor pathway inhibitor (TFPI) are markers of endothelial activation and damage, and may provide insights into disease pathogenesis or differences between phenotypes. We therefore measured these markers in a prospective series of patients with lacunar stroke. One hundred and ten white Caucasian patients with previous lacunar stroke and 50 community control subjects were studied. Markers of endothelial function were measured on venous blood samples. Patients were classified on brain imaging into two groups: isolated lacunar infarction (n = 47) and ischaemic leukoaraiosis, defined as a clinical lacunar stroke and leukoaraiosis on brain imaging (n = 63). The number of lacunes and severity of leukoaraiosis were also scored on MRI. ICAM1, TM and TFPI were elevated in cerebral SVD subjects compared with controls (P <or= 0.006). The ischaemic leukoaraiosis group had a different endothelial marker profile, with lower levels of TFPI (P = 0.01) and a higher TF/TFPI ratio (P = 0.01) compared with the isolated lacunar infarction group. TM levels were associated with the number of lacunes (P = 0.008) and the leukoaraiosis score (P = 0.03), but TF levels and the TF/TFPI ratio were associated only with the extent of leukoaraiosis (P <or= 0.02). These results suggest that there is evidence of chronic endothelial dysfunction in cerebral SVD, and endothelial prothrombotic changes may be important in mediating the ischaemic leukoaraiosis phenotype. Therapies which help to stabilize the endothelium may have a role in this group of patients.

Angiotensin converting enzyme insertion/deletion genotype is associated with leukoaraiosis in lacunar syndromes

OBJECTIVES

Pathological and clinical data suggest that patients presenting with ischaemic lacunar syndromes may be a heterogenous group. Those with isolated lacunar infarction are thought to have localised atherosclerosis whereas in those with coexisting leukoaraiois a distinct diffuse small vessel vasculopathy may be the predominant underlying pathology. The ACE insertion/deletion (I/D) polymorphism is an important candidate gene in ischaemic cerebrovascular disease but, where lacunar stroke specifically has been examined, there have been discrepant reports concerning a possible association. It was hypothesised that the influence of the ACE gene may be different among the two subgroups of ischaemic lacunar stroke reflecting the heterogeneity of the small vessel disease phenotype.

METHODS

Eighty four consecutive patients presenting with classic lacunar syndromes were studied. All had acute cranial CT to exclude primary intracerebral haemorrhage and these were subsequently assessed for the presence and extent of leukoaraiosis. All patients were genotyped for the ACE insertion/deletion polymorphism.

RESULTS

There was a significant difference in the distribution of ACE genotype with the DD genotype occurring more often in patients with leukoaraiosis and the II and ID genotypes occurring more often among those in whom this was absent (chi(2)=9.06, p=0.01). In a logistic regression model the ACE DD genotype remained as an independent predictor for the presence of leukoaraiosis (p=0.02) in patients presenting with classic lacunar syndromes.

CONCLUSION

This study supports the hypothesis that there may be different types of small vessel disease in patients with classic lacunar syndromes and that the influence of the ACE DD genotype may be relevant in mediating the diffuse form of vessel injury.

Stroke after internal jugular venous cannulation

OBJECTIVE

To alert clinicians to the stroke risk associated with carotid artery injury secondary to attempted internal jugular venous (IJV) cannulation.

METHODS

Case reports and review of the literature.

RESULTS

Four patients developed a stroke following carotid artery (CA) injury during attempted IJV cannulation using the landmark technique. In all cases the arterial puncture was detected immediately and firm pressure applied for several minutes. In three cases there was evidence of intimal injury and thrombus formation. Two strokes were delayed by more than 24 h. One patient died. A review of studies describing 4487 IJV line insertion attempts using the landmark technique reveals that 5.9% of attempts are associated with CA injury.

CONCLUSION

Cannulation of the IJV using visible and palpable landmarks is associated with a risk of stroke. Arterial injury and stroke should be mentioned when consent is obtained for cannulation. Consideration should be given to a reduction of the arterial injury risk by using ultrasound guidance during line insertion.

Use of magnetic resonance angiography to select candidates with recently symptomatic carotid stenosis for surgery: systematic review

OBJECTIVE

To determine if sufficient evidence exists to support the use of magnetic resonance angiography as a means of selecting patients with recently symptomatic high grade carotid stenosis for surgery.

DESIGN

Systematic review of published research on the diagnostic performance of magnetic resonance angiography, 1990-9.

MAIN OUTCOME MEASURES

Performance characteristics of diagnostic test.

RESULTS

126 potentially relevant articles were identified, but many articles failed to examine the performance of magnetic resonance angiography as a diagnostic test at the surgical decision thresholds used in major clinical trials on endarterectomy. 26 articles were included in a meta-analysis that showed a maximal joint sensitivity and specificity of 99% (95% confidence interval 98% to 100%) for identifying 70-99% stenosis and 90% (81% to 99%) for identifying 50-99% stenosis. Only four articles evaluated contrast enhanced magnetic resonance angiography.

CONCLUSIONS

Magnetic resonance angiography is accurate for selecting patients for carotid endarterectomy at the surgical decision thresholds established in the major endarterectomy trials, but the evidence is not very robust because of the heterogeneity of the studies included. Research is needed to determine the diagnostic performance of the most recent developments in magnetic resonance angiography, including contrast enhanced techniques, as well as to assess the impact of magnetic resonance angiography on surgical decision making and outcomes.

How to undertake a clinically relevant systematic review in a rapidly evolving field. Magnetic resonance angiography

OBJECTIVES

The aim was to determine which generations of the evolving technology of magnetic resonance angiography (MRA) are currently of clinical relevance in two clinical applications. Our purpose was to plan a systematic review that would be valuable both to purchasers driven by cost-effectiveness and to practicing clinicians.

METHODS

Information was gathered from a search of major bibliographic databases, from a short questionnaire sent to 500 U.K. vascular radiologists and vascular surgeons, and from local clinical experts. We asked which of the MRA techniques were currently used and, assuming availability, what would be their technique of choice.

RESULTS

There were 206 published articles that satisfied preliminary inclusion criteria: 69 discussed 2D time of flight (TOF); 47, 3D TOF; and 38, contrast-enhanced techniques. There were 162 questionnaires returned (60 radiologists, 102 surgeons). Of the total respondents, 77/162 (48%) used MRA in the assessment of carotid artery stenosis; 47/77 (61%) used 2D TOF; 32/77 (42%), 3D TOF; and 26/77 (34%), contrast-enhanced techniques. Thirty-five of 162 (22%) respondents used MRA in the assessment of peripheral vascular disease (PVD); 15/35 (43%) used 2D TOF, 4/35 (11%) used 3D TOF, and 22/35 (63%) used contrast-enhanced techniques. For those wishing to use MRA, contrast-enhanced techniques were the method of choice.

CONCLUSIONS

The TOF methods that represent earlier generations of the technology remain clinically relevant, and will therefore be included in our systematic review. To ensure complete and relevant coverage in reviews of other evolving technologies, it would be advisable to obtain data for guidance in a similar way.

Prevalence of permanent childhood hearing impairment in the United Kingdom and implications for universal neonatal hearing screening: questionnaire based ascertainment study

OBJECTIVE

To estimate the prevalence of confirmed permanent childhood hearing impairment and its profile across age and degree of impairment in the United Kingdom.

DESIGN

Retrospective total ascertainment through sources in the health and education sectors by postal questionnaire.

SETTING

Hospital based otology and audiology departments, community health clinics, education services for hearing impaired children.

PARTICIPANTS

Children born from 1980 to 1995, resident in United Kingdom in 1998, with severe permanent childhood hearing impairment (hearing level in the better ear >40 dB averaged over 0.5, 1, 2, and 4 kHz).

MAIN OUTCOME MEASURES

Numbers of cases with date of birth and severity of impairment converted to prevalences for each annual birth cohort (cases/1000 live births) and adjusted for under ascertainment.

RESULTS

26 000 notifications ascertained 17 160 individual children. Prevalence rose from 0.91 (95% confidence interval 0.85 to 0.98) for 3 year olds to 1.65 (1.62 to 1.68) for children aged 9-16 years. Adjustment for under ascertainment increased estimates to 1.07 (1.03 to 1.12) and 2.05 (2.02 to 2.08). Comparison with previous studies showed that prevalence increases with age, rather than declining with year of birth.

CONCLUSIONS

Prevalence of confirmed permanent childhood hearing impairment increases until the age of 9 years to a level higher than previously estimated. Relative to current yields of universal neonatal hearing screening in the United Kingdom, which are close to 1/1000 live births, 50-90% more children are diagnosed with permanent childhood hearing impairment by the age of 9 years. Paediatric audiology services must have the capacity to achieve early identification and confirmation of these additional cases.

Universal neonatal hearing screening: past, present, and future

After a brief review of the history of newborn hearing screening including the Downs behavioral testing procedure, the Crib-o-gram and similar devices, and the use of auropalpebral reflex and otoacoustic emissions, there is a discussion of key issues that need to be resolved before universal hearing screening is introduced. Included are questions regarding the target population(s) of screening programs, well baby versus NICU screening, dealing with false-positives and the effects on parent-child relationships, and finally, the availability of resources for screening and follow-up. The results of a recent study in the United Kingdom that assessed the current state of audiology services and found there is a difference between existing standards and what is actually being done in practice, are presented and considered in terms of current trends in the United States to move ahead with universal screening without a solid database of information regarding the preparedness of clinical centers to deal with the need for services that will result from the initiation of universal programs. Caution is urged.

Quantifying associated reactions in the paretic arm in stroke and their relationship to spasticity

OBJECTIVES

(1) To present a measurement protocol for assessing associated reactions (AR) in the paretic arm and (2) to use it to investigate the pattern of AR and its association with spasticity.

SETTING

Inpatient rehabilitation unit.

DESIGN

Associated reactions in 49 adults with stroke were measured in terms of force generated, electrical muscle activity and wrist movement in the paretic arm using hand dynamometry, surface electromyography and electrogoniometry respectively. Simultaneous recording of the effort used to elicit the associated reaction was made using a second hand dynamometer. The magnitude and persistence of AR was compared with the clinical assessment of spasticity (using the modified Ashworth Scale, MAS).

RESULTS

There was poor correlation between peak AR and MAS, suggesting that AR are not confined to patients with severe spasticity. Co-activation of forearm flexors and extensors was evident during the AR. AR fluctuated during a single period of effort in some patients. Only 12 out of 31 patients who maintained uniform effort over the measurement period produced a uniform AR. AR often persisted for some time after effort had ceased. Eight were classified as minimal (median AR 0.23 N), 25 as mild (median AR 2.7 N), 11 as moderate (median AR 6.4 N) and 3 as severe (median AR 11.0 N). AR tended to persist in patients with higher MAS although this result was not statistically significant.

CONCLUSION

The magnitude, profile and persistence of AR varied considerably between individuals. Associated reactions were present in people with minimal spasticity. As this technique allows the magnitude of AR to be quantified in relation to effort it has the potential to be a useful outcome measure in clinical trials evaluating the treatments (e.g. physiotherapy) directed at reducing associated reactions.

Primary diffuse leptomeningeal gliomatosis predominantly affecting the spinal cord: case report and review of the literature

Primary leptomeningeal gliomatosis is a rare, fatal neoplastic syndrome. A 71 year old man is reported on, who after a 2 month history of back stiffness, epigastric pain, and weight loss developed visual blurring. Cranial CT and MRI studies showed no leptomeningeal enhancement. Examination of CSF 10 weeks premortem showed an increase in protein and decrease in glucose but no malignant cells. He became increasingly confused and repeated CSF examination showed inflammation and a few suspicious cells but no definitive evidence of neoplasia. He died 7 months after onset of his initial symptoms. At postmortem meningeal whitening was seen at the base of the brain and over the spinal cord. Histology disclosed diffuse leptomeningeal gliomatosis (GFAP positive, cytokeratin negative) over the brain, optic nerves, and spinal cord without parenchymal involvement. No tumour was found in internal organs. The diagnosis of primary leptomeningeal gliomatosis was not evident after cranial CT and MRI and CSF examination premortem. Suspected cases need MRI scanning of the entire neuraxis and meningeal biopsy.

Impact of botulinum toxin type A on disability and carer burden due to arm spasticity after stroke: a randomised double blind placebo controlled trial

OBJECTIVES

After stroke, abnormal arm posture due to spasticity in a functionally useless arm may interfere with self care tasks. In these patients botulinum toxin treatment presents an opportunity to reduce disability. The purpose was to investigate whether reduction in spasticity after botulinum toxin treatment translates into reduction in disability and carer burden.

METHODS

Forty patients with stroke with spasticity in a functionally useless arm (median duration 3.1 years) were randomised to receive intramuscular botulinum toxin type A (BT-A; Dysport) (n=20) or placebo (n=20) in a total dose of 1000 MU divided between elbow, wrist, and finger flexors. Spasticity (using the modified Ashworth scale), muscle power, joint movement, and pain were assessed. Disability and carer burden were measured using an eight item and a four item scale respectively. Two baseline and three post-treatment assessments (weeks 2, 6, and 12) were made. Concurrent treatments as far as possible remained unchanged and not optimised.

RESULTS

Disability improved at week 6 with BT-A compared with placebo. This effect, present at week 2, wore off by week 12. Reduction in carer burden was seen at week 6 with BT-A and continued for at least 12 weeks. Forearm flexor spasticity was reduced with BT-A up to 12 weeks after treatment. Although significant improvement in elbow flexor spasticity was seen at week 2 with BT-A compared with placebo, this effect was not evident at weeks 6 and 12. Arm pain was not improved after BT-A. Grip strength was reduced with BT-A. No serious BT-A related adverse effects were reported.

CONCLUSION

BT-A is useful for treating patients with stroke who have self care difficulties due to arm spasticity. The decision to treat should also include relief of carer burden. As muscle weakness may occur, its potential impact on functional activities must be assessed before intervention.

Apolipoprotein E polymorphism in cerebrovascular disease

OBJECTIVES

The aim of this study was to investigate the relationship between the apo E genotype with acute cerebral infarction and primary intracerebral haemorrhage and to examine the relationship of the apo E genotype with mortality following acute stroke.

MATERIALS AND METHODS

We studied 592 cases of acute stroke and 289 healthy control subjects clinically free of cerebrovascular disease. Pathological type of stroke was determined by cranial computed tomography and the subtype of cerebral infarction classified according to the Oxfordshire Community Stroke Project Classification (OCSP). Apo E genotype was determined using polymerase chain reaction.

RESULTS

There was no difference in apo E genotype frequency between cases and controls (chi2 = 3.58, 5 d.f., P = 0.60). Apo E genotypes were not related to the pathological type of stroke (cerebral infarction, CI, n = 532 and primary intracranial haemorrhage, PICH, n = 60, (chi2 =3.738, 4 d.f., P=0.44) nor with the Oxfordshire Community Stroke Project Classification subtypes of cerebral infarction, lacunar infarction, LACI (n = 169), total anterior circulation infarction, TACI (n = 117), partial anterior circulation infarction, PACI (n = 173), posterior circulation infarction, POCS (n = 54) and including those cerebral infarcts which could not be classified (n= 19), chi2 =31.1, 20 d.f., P=0.153). At the time of the analysis, 243 cases (41.0%) had died. The median follow-up (including death) was 851 days. There was no relationship between time to death and apo E genotype in cases of either CI or PICH.

CONCLUSION

In this population, there was no relationship between the apolipoprotein E polymorphism and the pathogenesis of cerebral infarction or primary intracerebral haemorrhage. Apo E genotype was not related to all-cause mortality following stroke.

Association of the platelet glycoprotein IIb HPA-3 polymorphism with survival after acute ischemic stroke

BACKGROUND AND PURPOSE

The role of polymorphisms of the platelet glycoprotein (GP) IIb/IIIa receptor in the development of cardiovascular disease has been the subject of intensive research. The aim of this study was to determine the association of the HPA-3 polymorphism of platelet GPIIb with ischemic stroke and subsequent survival and to identify possible interactions of HPA-3 with classic risk factors.

METHODS

HPA-3 genotype was determined by restriction fragment length polymorphism in 515 patients with ischemic stroke and 423 healthy, age-matched control subjects.

RESULTS

There was no significant difference in the genotype distribution of patients and controls, nor was there any difference when patients were subclassified into small- and large-vessel disease. The genotype distribution of the 231 patients subsequently dying during 2.8 years of follow-up (aa=45.0%, ab=46.8%, bb=8.2%) was significantly different from that of those still alive (aa=37.0%, ab=48.2%, bb=14. 8%) (P=0.03). In a Cox regression model, the relative risks for poststroke mortality in patients of aa and ab genotype compared with those of bb genotype were 2.42 (95% CI, 1.24 to 4.71) and 2.13 (95% CI, 1.09 to 4.17), respectively, after we accounted for confounding factors. In addition, significant interactions of HPA-3 with the Pl(A) polymorphism of GPIIIa (P=0.002) and with fibrinogen (P=0.01) were identified in relation to mortality.

CONCLUSIONS

HPA-3 is related to poststroke mortality, and the significant interaction of HPA-3 with Pl(A) and fibrinogen suggests that it may in some way influence the interaction of GPIIb/IIIa with fibrinogen, particularly in the presence of high fibrinogen.

Evaluation of the use of a questionnaire to detect hearing loss in babies in China

A questionnaire was used to screen hearing of 1020 babies 6-8 months in China. All babies failing the questionnaire and 10% of those who passed were tested using auditory brainstem audiometry (ABR). Babies with unilateral or bilateral hearing thresholds 30 dBnHL or more were investigated to determine the cause of the hearing impairment. Sixty-seven failing the questionnaire were tested and 23 were confirmed to have a hearing loss, 20 with bilateral hearing impairment. The causes were: 13 otitis media with effusion (OME), one hypoxia, one genetic and five unknown. One child with an OME related hearing loss passed the screen. The sensitivity of the questionnaire was estimated to be 70%, specificity 96%.

Platelet GP IIIa PlA and GP Ib variable number tandem repeat polymorphisms and markers of platelet activation in acute stroke

A number of polymorphisms of the platelet glycoprotein (GP) Ib-V-IX and IIb/IIIa complexes have been described, and the PlA polymorphism of GP IIIa has been associated with coronary thrombosis. We determined the levels of beta-thromboglobulin (beta-TG) and platelet factor 4 (PF4) and the genotype distributions of PlA and a variable number tandem repeat (VNTR) polymorphism of GP 1b in subjects with acute stroke (n=609) and healthy control subjects (n=435). Levels of beta-TG were higher in patients both initially (47.4 [44.7 to 50.2] ng/mL, P<0.0001) and after 3 months (42.9 [40.3 to 45.7] ng/mL, P=0.03) compared with control subjects (39.4 [37.7 to 41.2] ng/mL). Initial levels of beta-TG were significantly higher in those who subsequently died (58.7 [52.3 to 65.8] ng/mL) compared with those still alive (42.7 [40.1 to 45.5] ng/mL, P<0.0001). In a logistic regression model, beta-TG remained an independent predictor of poststroke mortality, with an odds ratio for an increase in 10 ng/mL of 1.12 (1.03 to 1.21, P=0.006). In subjects who had never smoked, there was a significant difference in the genotype distributions of patients with atherothrombotic stroke (A1/A1=147, A1/A2=70, and A2/A2=2) compared with controls (A1/A1=165, A1/A2=47, and A2/A2=5, P=0.03). The PlA distribution of subjects with atherothrombotic stroke before the age of 50 years (A1/A1=19 and A1/A2+A2/A2=18) was also significantly different from age- and sex-matched controls (A1/A1=54 and A1/A2+A2/A2=20, P=0.02). We found no association of VNTR with stroke or poststroke mortality. These data indicate that there is a persistent state of enhanced platelet activation in subjects with acute stroke, which is associated with poststroke mortality. The increased frequency of the PlA2 allele in young subjects with atherothrombotic stroke lends further support for a role of the PlA polymorphism in acute thrombosis.

Polymorphisms of the factor VII gene and circulating FVII:C levels in relation to acute cerebrovascular disease and poststroke mortality

BACKGROUND AND PURPOSE

FVII:C has been shown to be an independent risk factor for myocardial infarction and is related to environmental and genetic factors. This study sought to investigate FVII:C levels and factor VII (FVII) gene polymorphisms in relation to stroke and disease outcome.

METHODS

To examine the association of FVII:C and the Msp I and promoter insertion polymorphisms of the FVII gene in acute stroke, 317 patients and 198 age-matched control subjects were studied.

RESULTS

FVII:C levels were significantly lower in patients at onset than 3 months later (119% versus 135%, respectively; P < .0005). Levels were significantly lower in patients at onset than in control subjects (124% [95% confidence interval, 120% to 129%] versus 141% [95% confidence interval, 135% to 148%], respectively; P < .0005) but were not significantly different at 3 months (135% [95% confidence interval, 128% to 141%] versus 141% [95% confidence interval, 135% to 148%], respectively). We found no difference in genotype distribution for either polymorphism between patients and control subjects, no difference in FVII:C level or genotype distribution between pathological types of stroke, and no relationship with poststroke mortality. Both polymorphisms were significantly associated with FVII:C levels in patients and control subjects. In a multiple regression model for patients, Msp I genotype, cholesterol, and smoking remained as independent predictors of FVII:C levels, accounting for 32% of interindividual variation.

CONCLUSIONS

These results suggest that neither FVII:C levels nor FVII gene polymorphisms are associated with cerebrovascular disease. There were no genotype-specific correlations of environmental factors with FVII:C, but there was evidence of an acute-phase or consumptive fall in FVII:C levels at the time of stroke, whereas levels increased to those similar for healthy age-matched control subjects by 3 months, when the acute phase had presumably subsided.

Plasminogen activator inhibitor-1 (PAI-1) 4G/5G promoter polymorphism and levels in subjects with cerebrovascular disease

The exact role of the fibrinolytic system in the pathogenesis of stroke remains to be established. Elevated circulating levels of plasminogen activator inhibitor-1, the principle inactivator of the fibrinolytic system, have been related to the development of myocardial infarction. There is evidence that a polymorphism in the promoter region of the PAI-1 gene is associated with circulating PAI-1 levels. We studied a common single nucleotide insertion/deletion (4G/5G) polymorphism by PCR in 558 patients with stroke, the pathological type of which was established by cranial computed tomography, and in 172 controls. 4G/5G genotype and PAI-1 activity were investigated in relation to 1) stroke type and 2) mortality occurring within four weeks, three months and six months of the stroke. No difference in genotype frequency was observed when all cases of stroke were compared with controls nor between the clinically determined subtypes of cerebral infarction. PAI-1 activity was significantly higher in patients with stroke (n = 245) both at presentation (11.6 U/ml) and after three months (11.8 U/ml), in paired samples, than in control subjects (8.8 U/ml, p < 0.0001). Thirty-seven (6.2%), 86 (14.5%) and 122 (20.5%) patients had died within one, three and six months of admission, respectively. PAI-1 activity was independently associated with all-cause mortality at one and three months after stroke (p = 0.02 and p = 0.03 respectively), but not after six months. In this population the 4G/5G promoter polymorphism is not associated with an increased risk of stroke. PAI-1 levels were elevated at the time of acute stroke which persisted after three months. PAI-1 level but not genotype was associated with early mortality following stroke.

Gender-specific associations of the fibrinogen B beta 448 polymorphism, fibrinogen levels, and acute cerebrovascular disease

Fibrinogen is an independent risk factor for the development of stroke. Factors influencing circulating levels of fibrinogen include age, smoking, gender, and genetic factors. The aim of this study was to determine the relationship between a polymorphism at position 448 of the B beta fibrinogen gene, fibrinogen levels, gender, and the risk of stroke. Fibrinogen levels were determined in 305 patients with stroke, taken within 10 days of the acute event and 3 months later, and in 197 control subjects. Initial fibrinogen levels in patients (4.49 g/L) were significantly higher than at 3 months (3.85 g/L, P < .0001), consistent with resolution of the acute-phase response. At 3 months, levels were only significantly higher than for control subjects in the male patients (3.86 g/L versus 3.31 g/L, P < .0001). Fibrinogen levels were associated with B beta 448 genotype in male patients at 3 months (1/1 = 3.62 g/L, 1/2 + 2/2 = 4.27 g/L, P = .01). There was a significant difference in the genotype distribution in female patients and control subjects (patients: 1/1 = 95, 1/2 = 34, 2/2 = 6; control subjects: 1/1 = 61, 1/2 = 50, 2/2 = 3, P = .008). These data suggest that the mechanisms linking fibrinogen and the development of cerebrovascular disease are different in males and females. In male patients, the increase in fibrinogen levels may be influenced by environmental factors, while in females there may be a functional difference in the fibrinogen molecule unrelated to fibrinogen levels.

Use of botulinum toxin in stroke patients with severe upper limb spasticity

OBJECTIVES

Spasticity can contribute to poor recovery of upper limb function after stroke. This is a preliminary evaluation of the impact of botulinum toxin treatment on disability caused by upper limb spasticity after stroke.

METHODS

Seventeen patients with severe spasticity and a non-functioning arm were treated with intramuscular botulinum A neurotoxin (median age at treatment 54.5 years; median time between onset of stroke and treatment 1.5 years). Baseline and assessments two weeks after treatment were compared to assess efficacy. The duration of improvement in disability was documented. Outcome measures used were; passive range of movement at the shoulder, elbow, wrist, and fingers; modified Ashworth scale to assess spasticity of biceps and forearm finger flexors; an eight point scale to assess the degree of difficulty experienced by the patient or carer for each functional problem defined before treatment; the presence of upper limb pain. The biceps, forearm finger flexors, and flexor carpiulnaris were treated with intramuscular botulinum toxin. Up to a total dose of 400-1000 mouse units (MU) of Dysport (Speywood) or 100-200 MU of BOTOX (Allergan) was used in each patient.

RESULTS

Functional problems reported by the patients before treatment were difficulty with cleaning the palm, cutting fingernails, putting the arm through a sleeve, standing and walking balance, putting on gloves, and rolling over in bed. Hand hygiene improved in 14 of 17 patients; difficulty with sleeves improved in four of 16; standing and walking balance improved in one of four; shoulder pain improved in six of nine; wrist pain improved in five of six. Passive range of movement at shoulder, elbow, and wrist improved after treatment. Benefit was noted within two weeks and lasted one to 11 months. No adverse effects occurred.

CONCLUSION

This preliminary study suggests that intramuscular botulinum toxin is a safe and effective treatment for reducing disability in patients with severe upper limb spasticity.

Real ear to coupler differences in children having otitis media with effusion

The aim of this study was to investigate the effects of otitis media with effusion (OME) on the 'real ear to coupler difference' (RECD) in children. RECDs are important in the procedures used for selection of appropriate amplification characteristics for children with permanent (usually sensorineural) hearing impairment. Subjects were 28 children aged between 4.6 and 7.6 years, 14 of whom had OME. There was no evidence of middle ear pathology in the remaining 14 who comprised the control group. All real-ear and coupler measures showed good test-retest repeatability at 4.0 kHz and below. The mean RECDs in frequency range 0.2-3.0 kHz were found to be up to 3.5 dB greater for the children having OME than for those without OME, although when statistically analysed only the differences in RECD at 1.0 kHz and 1.5 kHz were significant. Due to low correlation between the root mean square (RMS) sound pressure level (SPL) in the ear canal and ear canal volume, and low correlation between the subject's maximum RECD and ear canal volume, neither of these other variables could be used to predict an individual's RECD in this study. Large inter-subject variability was found, with a maximum standard deviation of 5.6 dB at 0.2 kHz, so this study greatly supports the need for individual RECD measurements to be made whenever possible, rather than using averaged transformation figures, particularly if the individual has OME.

Otoacoustic emission versus ABR screening: the effect of external and middle ear abnormalities in a group of SCBU neonates

Twenty neonates in a special care baby unit (SCBU) were tested using automated procedures for obtaining auditory brainstem responses (ABR) and transient evoked otoacoustic emissions (TEOAE). All 40 ears passed the initial ABR screen, while the pass rate for the TEOAE screen was only 52.5%. Ears with no external or middle ear abnormalities (group A) had a significantly higher TEOAE pass rate (94.7%) than those with at least one abnormality (group B) as detected by otoscopic examination and tympanometry (14.3%). Other variables, such as age at test, gestational age at birth and birth weight, did not differ significantly between groups A and B. We conclude that external/middle ear abnormalities in this group of neonates had no effect on the ABR screening results, but had a significant effect on the TEOAE screening results.

Vasospasm causing a cold hemiplegic arm

We report a case of a patient with abnormal coldness of the hemiplegic arm following a stroke.

Selecting the gain for radio microphone (FM) systems: theoretical considerations and practical limitations

This paper provides theoretical estimates of the signal-to-noise (S/N) ratio advantage that can be gained from a radio microphone (FM) system used with an environmental (EV) microphone, compared with the S/N ratio delivered by a conventional hearing aid alone. These estimates show that the S/N advantage gained is a function of the speaker/listener distance and the FM/EV gain difference, the greater the distance and the closer the FM gain is to the EV gain, the greater the S/N advantage. The implications for choice of FM and EV gain when fitting FM systems are discussed. The two goals of equating the FM and EV outputs and maximizing the S/N ratio are mutually incompatible. It is concluded that the FM gain should be set to be 10dB less than the EV gain unless the situation can be closely monitored, in which case the FM gain should be set as high as possible consistent with loudness tolerance and acceptable levels of distortion.

Probe-tube microphone measures with very young infants: real ear to coupler differences and longitudinal changes in real ear unaided response

OBJECTIVE

The feasibility and practicalities of performing probe-tube microphone measures with infants is addressed, as well as two aspects of acoustic functioning of infant ears: the real ear unaided response (REUR) and the real ear to coupler difference (RECD).

DESIGN

Part 1 is a longitudinal study involving 12 infants. Serial measures of REUR were obtained over an 18-mo period. Infants were < or = 3 mo for the first test and < or = 21 mo at the last test visit. Practicalities of probe-tube microphone testing of unsedated infants and changes in the position (i.e., frequency) of the primary REUR peak were addressed. For part 2 of the project, 33 infants under 12 mo of age took part. A comparison of real ear hearing aid gain versus coupler gain was made. Test-retest differences for real ear aided response were estimated.

RESULTS

Part 1 results indicate that probe-tube microphone measures in unsedated infants are feasible and show good within-subject repeatability. REUR measures for the more alert and mobile older subjects, as for the younger infants, showed an acceptably small degree of intersubject variability. The frequency of the primary REUR peak decreased during the first year of life, with a group mean of 2932 Hz reached at the end of the first year. However, thereafter, instead of stabilizing at around this value there was considerable fluctuation in the frequency of REUR peak. For Part 2, results a) confirmed the large RECD value for infants in the first year of life and b) showed a high degree of intersubject variability. Test retest measures of real ear aided response (REAR) gave values small enough to indicate the clear potential of probe-microphone use with infants during the hearing aid selection and fitting process.

CONCLUSION

These findings should encourage attempts to carry out individual probe-tube microphone measurements with very young infants. They point to the need for infant hearing aid fitting procedures which involve such measurements to secure appropriate amplification.

Long-term survival after first-ever stroke: the Oxfordshire Community Stroke Project

BACKGROUND AND PURPOSE

There have been relatively few community-based studies of long-term prognosis after acute stroke. This study aimed to provide precise estimates of the absolute and relative risks of dying in an unselected cohort of patients with a first-ever stroke.

METHODS

Six hundred seventy-five patients were registered by a community-based stroke register (the Oxfordshire Community Stroke Project) and prospectively followed up for up to 6.5 years. Their relative risk of death was calculated using age- and sex-specific mortality rates for Oxfordshire.

RESULTS

During the first 30 days, 129 (19%) patients died. Patients who survived at least 30 days after a first-ever stroke thereafter had an average annual risk of death of 9.1%, 2.3-fold the risk in people from the general population. Although the absolute (about 15%) and relative (about threefold) risks of death were highest in these 30-day survivors over the first year after the stroke, they were at increased risk of dying over the next few years (range of relative risk for individual years, 1.1-2.9). Predictably, older patients had a worse absolute survival but, relative to the general population, stroke also increased the relative risk of dying in younger patients. During the first 30 days stroke accounts for most deaths; after this time nonstroke cardiovascular disease becomes increasingly important and is the most common cause of death after the first year.

CONCLUSIONS

These data highlight the importance of long-term secondary prevention of vascular events in stroke patients, targeted as much at the cardiovascular as at the cerebrovascular circulation.

Probe-tube microphone measurements with very young infants

The practicalities of performing probe-tube microphone measurements in a clinical environment with unsedated infants were examined. External ear resonance curves (unaided response) were obtained for both ears of a group of infants aged 0-6 months and an adult comparison group. A repeat measure (with probe-tube repositioning) was made to estimate the test-retest reliability of these measures. Results showed that the mean infant resonance frequency (4200 Hz) occurred at a significantly (P less than 0.005) higher frequency than the mean adult resonance frequency (2950 Hz). Infants test-retest differences for resonance frequency (mean = 286 Hz, s.d. = 404 Hz) and size of peak (mean = 2.2 dB, s.d. = 2.6 dB) showed acceptable stability for the measurements. Size of resonance peak was found to vary positively with ear canal volume; however, estimation of ear canal volume from tympanometry did not provide a useful indicator of the size of the peak. The probe-microphone measurements were found to be feasible, repeatable and practical with these infants.

Acoustic evaluation of earmoulds in situ: a comparison of impression and earmould materials

Laboratory research has been carried out on the accuracy of both ear impression and earmould materials. The present work was undertaken to assess such materials in vivo. An objective clinical method of earmould evaluation was developed, based on estimation of the attenuation in the acoustic feedback path. The method was used to assess the acoustic performance of earmoulds made from three earmould materials of different texture, when prepared from two different impression materials. It was shown that the choice of impression material made a significant difference to earmould performance. For greatest accuracy, addition cured silicone impression materials are recommended.