External quality monitoring facilitates improvement in already well-performing stroke units: insights from RES-Q Poland

INTRODUCTION

The Registry of Stroke Care Quality (RES-Q) is used in Poland for quality monitoring by numerous hospitals participating in the Angels Initiative. Our aim was to assess the degree of improvement in highly stroke-oriented centres that report cases to the RES-Q each year.

MATERIAL AND METHODS

This retrospective analysis included Polish stroke units that from January 2017 to December 2020 contributed to the RES-Q at least 25 patients annually.

RESULTS

Seventeen out of 180 Polish stroke units reported patients each year (2017, n = 1,691; 2018, n = 2,986; 2019, n = 3,750; 2020, n = 3,975). The percentage of ischaemic stroke patients treated with alteplase remained stable (26%, 29%, 30% and 28%, respectively). The door-to-needle time progressively decreased, from a median 49 minutes to 32 minutes. The percentage of patients treated ≤ 60 minutes and ≤ 45 minutes significantly increased (from 68% to 86% and from 43% to 70%, respectively), with no change observed between 2019 and 2020. Despite a general improvement in dysphagia screening (81%, 91%, 98% and 99%), screening performed within the first 24h from admission became less frequent (78%, 76%, 69% and 65%). In-hospital mortality significantly increased (11%, 11%, 13% and 15%), while the proportion of patients discharged home remained stable.

CONCLUSIONS

Quality-oriented projects facilitate the improvement of stroke care, even in centres demonstrating good baseline performance. Polish stroke units that consistently reported cases to the RES-Q demonstrated improvement in terms of door-to- -needle time and dysphagia screening. However, there is still a need to shorten the time to dysphagia screening, and carefully monitor stroke unit mortality following the COVID-19 pandemic.

Brain injury mobile diagnostic system: Applications in civilian medical service and on the battlefield-General concept and medical aspects

To present the concept of a portable ultrasound tomography device for diagnosing traumatic and vascular brain lesions. The device consisting of multiple transcranial ultrasound probes placed on the surface of the head, specifically but not exclusively in natural acoustic windows. An integral part of the mobile diagnostic system (MDS) is a decision support system based on artificial intelligence algorithms utilizing information from: head images, laboratory data, and assessment of the patient's clinical condition. The MDS can significantly reduce the time from stroke onset to rtPA therapy in civilian medical services and support therapeutic and evacuation strategies in instances of brain and skull trauma on the battlefield.

Significance of pulse pressure variability in predicting functional outcome in acute ischemic stroke: a retrospective, single-center, observational cohort study

This study aimed to determine the association between pulse pressure variability (PPV) and short- and long-term outcomes of acute ischemic stroke (AIS) patients. We studied 203 tertiary stroke center patients with AIS. PPV during 72 h after admission was analyzed using different variability parameters including standard deviation (SD). Patients' outcome was assessed after 30 and 90 days post-stroke with modified Rankin Scale. The association between PPV and outcome was investigated using logistic regression analysis with adjustment for potential confounders. The predictive significance of PPV parameters was determined using area under the curve (AUC) of receiver operating characteristics. In the unadjusted logistic regression analysis, all PPV indicators were independently associated with unfavorable outcome at 30 days (i.a. Odds ratio (OR) = 4.817, 95%CI 2.283-10.162 per 10 mmHg increase in SD, p = 0.000) and 90 days (i.a. OR = 4.248, 95%CI 2.044-8.831 per 10 mmHg increase in SD, p = 0.000). After adjustment for confounders, ORs for all PPV indicators remained statistically significant. On the basis of AUC values, all PPV parameters were found relevant outcome predictors (p < 0.01). In conclusion, elevated PPV during first 72 h after admission due to AIS is associated with unfavorable outcome at 30 and 90 days, independent of mean blood pressure levels.

Association between nocturnal oxygen desaturation and ischaemic stroke outcomes

CLINICAL RATIONALE FOR THE STUDY

This study aimed to assess the association between nocturnal hypoxemia and early acute ischaemic stroke (AIS) outcomes in patients without oxygen supplementation.

MATERIAL AND METHODS

One hundred and six AIS patients consecutively admitted to the stroke unit were included in this study. Baseline demographic and medical data and arterial blood saturation (SpO2) measurements during night-sleep (from 10pm to 6am) were examined for their association with stroke outcomes, including the National Institutes of Health Stroke Scale (NIHSS) score on the 7th day or differences between the NIHSS score on the 1st day and the 7th day after stroke onset. Measurements of SpO2 were made using a pulse oximeter of the Spacelabs Medical Inc. (USA) monitoring system, and the number of apnoea episodes and their duration were recorded by ECG Holter with respiration monitoring (CardioMem®, Getamed, GE).

RESULTS

The study showed that age (Spearman's r = 0.207, p = 0.033) and parameters attributable to anaemia (RBC r = -0.205, p = 0.035, Hb r = -0.225, p = 0.02 and HCT r = -0.196, p = 0.044), atrial fibrillation and ischaemic changes in both brain hemispheres (p = 0.023 and 0.01, respectively) were correlated with the study outcomes. In terms of saturation parameters, we demonstrated that the 'total desaturation burden' (i.e. [100% minus actual measured SpO2%] x apnoea duration) and multiple apnoeas of longer than 20 seconds were correlated with worse functional outcomes. Measures of shorter desaturation episodes (i.e. SpO2 oxygen desaturation index (ODI) at 3% and 4%, and time-weighted desaturations below the determined thresholds (SpO2 from 95% to 85%) demonstrated non-significant associations with the study outcomes.

CONCLUSIONS AND CLINICAL IMPLICATIONS

This study demonstrated that long-lasting desaturation episodes during the night, depicted by the 'total desaturation burden', were correlated with worse functional outcomes in AIS, while measures of shorter desaturation episodes were not correlated. In future clinical trials, indications for oxygen supplementation should include the methodology of personalised medicine and introduce individual approaches based on specially formulated, novel multifactorial algorithms.

Effect of Face Masks on Blood Saturation, Heart Rate, and Well-Being Indicators in Health Care Providers Working in Specialized COVID-19 Center

This study aims to investigate whether wearing face masks (filtering facepieces, FFP class 2) with personal protective equipment (FPP2/PPE), while working a 12-h shift in a COVID-19 referral center, affects the blood saturation, heart rate (HR), and well-being of health care providers (HCPs). The study included a group of 37 HCPs. To perform continuous recordings of the SpO₂ and heart rate (HR) in real time, we used a Nellcor PM10N (Covidien, Mansfield, MA, USA) portable monitoring system. SpO₂, HR, and HCP well-being scales were measured during two 3-h shifts, while HCPs worked during a 12-h period. Additionally, each subject completed a questionnaire concerning their well-being. The difference in the SpO₂ level between the 1st and 2nd working shifts while wearing an FFP2/PPE was small, with a median decrease in SpO₂ of -1%. The scales of the well-being indicators increased within the shift. They were mainly fatigue and thirst with median scores of 2 out of 6 (range 0-4). We assume that during a 12-h period, a work scheme that consists of a 3-h shift in FFP2/PPE and a 3-h rest period (working without FPP2/PPE) is a reliable and safe solution for HCPs working in specialized COVID-19 referral hospitals.

The impact of FFP3 respirators on the blood saturation

This study aims to investigate whether wearing a filtering facepiece class 3 respirators with personal protective equipment (FPP3/PPE) during work in the intensive care unit (ICU) affects the blood saturation (SpO2), the heart rate (HR), and the well-being of health care workers (HCWs). This preliminary study included a group of 21 volunteers (including 16 females (76%), with a median age of 23 years). Each worker served as his own control and performed the test two times: they wore the FFP3/PPE and did not wear it for a three-hour shift in the ICU. The working with an FFP3/PPE compared to not working with an FFP3/PPE caused a significant, but within normal ranges, influence on the level of SpO2 with a mean decrease of - 1.43%. The highest reduction in the SpO2 was - 2.29% and occurred after 150 min of work. All of the score scales of the well-being markers increased consecutively but moderately during the shift while wearing the FFP3/PPE. We assume that a 3-h shift rhythm is a safe and reliable solution, i.e., three hours of working in the FFP3/PPE in the ICU, followed by rest or working without an FFP3/PPE.

Serum Proteome Alterations in Human Cystathionine β-Synthase Deficiency and Ischemic Stroke Subtypes

Ischemic stroke induces brain injury via thrombotic or embolic mechanisms involving large or small vessels. Cystathionine β-synthase deficiency (CBS), an inborn error of metabolism, is associated with vascular thromboembolism, the major cause of morbidity and mortality in affected patients. Because thromboembolism involves the brain vasculature in these patients, we hypothesize that CBS deficiency and ischemic stroke have similar molecular phenotypes. We used label-free mass spectrometry for quantification of changes in serum proteomes in CBS-deficient patients (n = 10) and gender/age-matched unaffected controls (n = 14), as well as in patients with cardioembolic (n = 17), large-vessel (n = 26), or lacunar (n = 25) ischemic stroke subtype. In CBS-deficient patients, 40 differentially expressed serum proteins were identified, of which 18 were associated with elevated homocysteine (Hcy) and 22 were Hcy-independent. We also identified Hcy-independent differentially expressed serum proteins in ischemic stroke patients, some of which were unique to a specific subtype: 10 of 32 for cardioembolic vs. large-vessel, six of 33 for cardioembolic vs. lacunar, and six of 23 for large-vessel vs. lacunar. There were significant overlaps between proteins affected by CBS deficiency and ischemic stroke, particularly the cardioembolic subtype, similar to protein overlaps between ischemic stroke subtypes. Top molecular pathways affected by CBS deficiency and ischemic stroke subtypes included acute phase response signaling and coagulation system. Similar molecular networks centering on NFκB were affected by CBS deficiency and stroke subtypes. These findings suggest common mechanisms involved in the pathologies of CBS deficiency and ischemic stroke subtypes.

Spatial distribution of white matter degenerative lesions and cognitive dysfunction in relapsing-remitting multiple sclerosis patients

AIM

The aim of this study was to assess degenerative lesion localisation in the course of relapsing-remitting multiple sclerosis (RRMS) and to identify the association between localisation and the frequency of T1-hypointense lesions (black holes) with cognitive dysfunction. We also searched for neuroradiological predictors of cognitive dysfunction in patients. The clinical rationale for the study was previous research, and our own findings suggest that lesion localisation plays an important role in cognitive performance and neurological disability of MS patients.

MATERIAL AND METHODS

Forty-two patients were included in the study. All subjects underwent neuropsychological examination using Raven's Coloured Progressive Matrices, a naming task from the Brief Repeatable Battery of Neuropsychological Tests, and attention to detail tests. Magnetic resonance imaging (MRI) was acquired on 1.5 Tesla scanner and black holes were manually segmented on T1-weighted volumetric images using the FMRIB Software Library. Linear regression was applied to establish a relationship between black hole volume per lobe and cognitive parameters. Bonferroni correction of voxelwise analysis was used to correct for multiple comparisons.

RESULTS

The following associations between black hole volume and cognition were identified: frontal lobes black hole volume was associated with phonemic verbal fluency (t = -4.013, p < 0.001), parietal black hole volume was associated with attention (t = -3.776, p < 0.001), and parietal and temporal black hole volumes were associated with nonverbal intelligence (p < 0.001). The volume of parietal black holes was the best predictor of cognitive dysfunction.

CONCLUSIONS

Our approach, including measurement of focal axonal loss based on T1-volumetric MRI sequence and brief neuropsychological assessment, might improve personalised diagnostic and therapeutic decisions in clinical practice.

Internet Usage by Polish Patients With Multiple Sclerosis: A Multicenter Questionnaire Study

Background

The internet is a source of knowledge and medium widely used in services that facilitate access to information and networking. Multiple sclerosis (MS) patients find the possibility of acquiring information relating to their condition particularly rewarding.

Objective

We aimed to identify Polish MS patients’ preferences by analyzing a percentage of internet users and determining the most common search subjects and patients’ approach to information on the internet. Disability connected with the condition, its duration, and other factors that influence patients’ internet use were examined along with instances of relations established through the internet and their durability.

Methods

The study examined 1045 patients (731 women, 314 men) treated in 10 Polish MS centers, of whom 932 (89.19%) declared to be internet users. Their average age was 40.65 (SD 11.06) and average MS duration was 9.08 (SD 6.97) years. The study used a proprietary survey on information seeking, the range of searched subjects, and internet usage frequency.

Results

The majority of the patients (494/932, 53.0%) used the internet 6-7 times per week and 4.3% (40/932) declared they spent minimum 2 hours per day. The most commonly searched subjects were world news (604/932, 72.9% of patients using the internet); 60.8% (504/932) searched for information on their condition, particularly for new treatment methods (562/932, 67.8%) and the course of illness (520/932, 62.7%). One’s sex had no impact on internet usage (female vs male, odds ratio [OR] 1.13, 95% CI 0.72-1.77), although a patient’s age might, at varying degrees. We found several significant associations using a .05 significance level: a patient with higher education used the internet 9 times more often than one with primary education (OR 8.64, 95% CI 3.31-22.57); lasting relationships increased chances of internet usage by 10-fold compared to widowers (OR 0.12, 95% CI 0.05-0.31); living in a city with a population over 100,000 increased chances by nearly 6 times compared with the countryside (OR 5.59, 95% CI 2.72-11.48); the relapsing-remitting MS type saw a 2-fold increase compared with the primary progressive MS type (OR 0.47, 95% CI 0.29-0.75); and those needing assistance were 2 times less likely to use the internet than patients who could move independently (OR 0.53, 95% CI 0.31-0.89). More than half of the patients (489/932, 52.5%) did not discuss the information found on the internet with their neurologists; 15.9% (148/932) believed that relationships established through the internet can be stable.

Conclusions

The majority of Polish patients use the internet as a crucial information source on their condition and innovative treatment methods. The internet can be helpful in establishing new relationships, which are usually short-lived. Polish patients do not frequently discuss the information gathered on the internet with their doctors.

Depressive symptoms in stroke patients treated and non-treated with intravenous thrombolytic therapy: a 1-year follow-up study

INTRODUCTION

This is a prospective study, first to compare the frequency of depressive symptoms in stroke survivors treated, and non-treated, with intravenous thrombolysis and second, to explore relationships between post-stroke depression (PSD) and stroke treatment modalities, taking into account other possible determinants of PSD, including post-traumatic stress symptoms.

METHODS

Groups of 73 thrombolysed and 73 non-thrombolysed patients matched for age and gender were examined at 3 and 12 months after discharge. PSD was assessed using the Beck Depression Inventory. Post-traumatic stress symptoms (PTSS), disability and social support were assessed with the Impact of Event Scale-Revised, the Barthel Index and the Berlin Social Support Scale.

RESULTS

At 3 months, PSD was present in 23.3% of the thrombolysed and 31.5% in the non-thrombolysed groups (p = 0.265). At 12 months, the frequencies were 29.2 and 20.6% (p = 0.229). Logistic regression of the combined group of thrombolysed and non-thrombolysed patients indicated that at 3 months, the adjusted predictors of PSD were disability (OR 24.35), presence of PTSS (OR 9.32), low social support (OR 3.68) and non-thrombolytic treatment (OR 3.19). At 12 months, the predictors were disability (OR 15.78) and low education (OR 3.61).

LIMITATIONS

The use of a questionnaire for the detection of depression, the relatively small sample size and a significant drop-out rate could limit the interpretation of these results.

CONCLUSIONS

(1) Thrombolysed and non-thrombolysed stroke survivors had similar frequency of depressive symptoms although the thrombolysed patients had more severe neurological deficits in the acute phase. It can be assumed that if thrombolysis had not been used, depressive symptoms would have been more frequent. (2) Lack of the rt-PA treatment was associated with three-time greater odds of screening for PSD at 3 months post-stroke, after adjustment for other PSD correlates. (3) Therefore, thrombolytic therapy seems to have a positive, but indirect, effect on patients' mood, especially in the first months after stroke. (4) All stroke patients, irrespective of the method of treatment, should be monitored for the presence of depression.

Mechanical thrombectomy in acute stroke - Five years of experience in Poland

OBJECTIVES

Mechanical thrombectomy (MT) is not reimbursed by the Polish public health system. We present a description of 5 years of experience with MT in acute stroke in Comprehensive Stroke Centers (CSCs) in Poland.

METHODS AND RESULTS

We retrospectively analyzed the results of a structured questionnaire from 23 out of 25 identified CSCs and 22 data sets that include 61 clinical, radiological and outcome measures.

RESULTS

Most of the CSCs (74%) were founded at University Hospitals and most (65.2%) work round the clock. In 78.3% of them, the working teams are composed of neurologists and neuro-radiologists. All CSCs perform CT and angio-CT before MT. In total 586 patients were subjected to MT and data from 531 of them were analyzed. Mean time laps from stroke onset to groin puncture was 250±99min. 90.3% of the studied patients had MT within 6h from stroke onset; 59.3% of them were treated with IV rt-PA prior to MT; 15.1% had IA rt-PA during MT and 4.7% - emergent stenting of a large vessel. M1 of MCA was occluded in 47.8% of cases. The Solitaire device was used in 53% of cases. Successful recanalization (TICI2b-TICI3) was achieved in 64.6% of cases and 53.4% of patients did not experience hemorrhagic transformation. Clinical improvement on discharge was noticed in 53.7% of cases, futile recanalization - in 30.7%, mRS of 0-2 - in 31.4% and mRS of 6 in 22% of cases.

CONCLUSION

Our results can help harmonize standards for MT in Poland according to international guidelines.

Standards in neurosonology. Part III

The paper presents standards related to ultrasound imaging of the cerebral vasculature and structures. The aim of this paper is to standardize both the performance and description of ultrasound imaging of the extracranial and intracranial cerebral arteries as well as a study of a specific brain structure, i.e. substantia nigra hyperechogenicity. The following aspects are included in the description of standards for each ultrasonographic method: equipment requirements, patient preparation, study technique and documentation as well as the required elements of ultrasound description. Practical criteria for the diagnosis of certain pathologies in accordance with the latest literature were also presented. Furthermore, additional comments were included in some of the sections. Part I discusses standards for the performance, documentation and description of different ultrasound methods (Duplex, Doppler). Part II and III are devoted to standards for specific clinical situations (vasospasm, monitoring after the acute stage of stroke, detection of a right-to-left shunts, confirmation of the arrest of the cerebral circulation, an assessment of the functional efficiency of circle of Willis, an assessment of the cerebrovascular vasomotor reserve as well as the measurement of substantia nigra hyperechogenicity).

Standards in neurosonology. Part II

The paper presents standards related to ultrasound imaging of the cerebral vasculature and structures. The aim of this paper is to standardize both the performance and description of ultrasound imaging of the extracranial and intracranial cerebral arteries as well as a study of a specific brain structure, i.e. substantia nigra hyperechogenicity. The following aspects are included in the description of standards for each ultrasonographic method: equipment requirements, patient preparation, study technique and documentation as well as the required elements of ultrasound description. Practical criteria for the diagnosis of certain pathologies in accordance with the latest literature were also presented. Furthermore, additional comments were included in some of the sections. Part I discusses standards for the performance, documentation and description of different ultrasound methods (Duplex, Doppler). Part II and III are devoted to standards for specific clinical situations (vasospasm, monitoring after the acute stage of stroke, detection of a right-to-left shunts, confirmation of the arrest of the cerebral circulation, an assessment of the functional efficiency of circle of Willis, an assessment of the cerebrovascular vasomotor reserve as well as the measurement of substantia nigra hyperechogenicity).

Standards in neurosonology. Part I

The paper presents standards related to ultrasound imaging of the cerebral vasculature and structures. The aim of this paper is to standardize both the performance and description of ultrasound imaging of the extracranial and intracranial cerebral arteries as well as a study of a specific brain structure, i.e. substantia nigra hyperechogenicity. The following aspects are included in the description of standards for each ultrasonographic method: equipment requirements, patient preparation, study technique and documentation as well as the required elements of ultrasound description. Practical criteria for the diagnosis of certain pathologies in accordance with the latest literature were also presented. Furthermore, additional comments were included in some of the sections. Part I discusses standards for the performance, documentation and description of different ultrasound methods (Duplex, Doppler). Part II and III are devoted to standards for specific clinical situations (vasospasm, monitoring after the acute stage of stroke, detection of a right-toleft shunts, confirmation of the arrest of the cerebral circulation, an assessment of the functional efficiency of circle of Willis, an assessment of the cerebrovascular vasomotor reserve as well as the measurement of substantia nigra hyperechogenicity).

Efficacy of cerebral thrombolysis in an extended 'time window'

WHAT IS KNOWN AND OBJECTIVE

Cerebral systemic thrombolysis (i.v. thrombolysis) with tissue-type plasminogen activator (rt-PA) is the only proven medical therapy for ischaemic stroke. The use of i.v. thrombolysis up to 4·5 h from stroke onset was approved in certain countries in 2008, but its safety and efficacy have not been fully determined to date.

OBJECTIVE

To assess the long-term outcome and complication rate of i.v. thrombolysis performed in the extended 'time window'.

METHODS

The study included 403 ischaemic stroke patients consecutively treated with i.v. thrombolysis from 2006 to 2012 at three comprehensive stroke centres in Poland. The long-term outcome and the haemorrhagic complications' (HC) rate were compared between subgroups of patients treated within 3 vs. 3-4·5 h from stroke onset.

RESULTS AND DISCUSSION

About 132 (32·75%) patients were treated between 3 and 4·5 h from stroke onset. Neurological deficits tended to be more severe in patients treated ≤3 than in those treated 3-4·5 h (National Institutes of Health Stroke Scale, NIHSS 12 vs.10 points; P = 0·053); however, the ratio of patients with a favourable outcome (mRS 0-2 points) and mortality did not differ between the two groups (53·9 vs. 58·3, P = 0·39 and 17·7 vs. 21·2, P = 0·39, respectively). The rate of HC also did not differ between the two groups (18·8% vs. 15·1%, P = 0·46).

WHAT IS NEW AND CONCLUSION

The efficacy of i.v. thrombolysis routinely performed in an extended 'time window' is not reduced when compared to procedures performed within 3 h from symptom onset.

The taxonomy statistic uncovers novel clinical patterns in a population of ischemic stroke patients

In this paper, we describe a simple taxonomic approach for clinical data mining elaborated by Marczewski and Steinhaus (M-S), whose performance equals the advanced statistical methodology known as the expectation-maximization (E-M) algorithm. We tested these two methods on a cohort of ischemic stroke patients. The comparison of both methods revealed strong agreement. Direct agreement between M-S and E-M classifications reached 83%, while Cohen's coefficient of agreement was κ = 0.766(P < 0.0001). The statistical analysis conducted and the outcomes obtained in this paper revealed novel clinical patterns in ischemic stroke patients. The aim of the study was to evaluate the clinical usefulness of Marczewski-Steinhaus' taxonomic approach as a tool for the detection of novel patterns of data in ischemic stroke patients and the prediction of disease outcome. In terms of the identification of fairly frequent types of stroke patients using their age, National Institutes of Health Stroke Scale (NIHSS), and diabetes mellitus (DM) status, when dealing with rough characteristics of patients, four particular types of patients are recognized, which cannot be identified by means of routine clinical methods. Following the obtained taxonomical outcomes, the strong correlation between the health status at moment of admission to emergency department (ED) and the subsequent recovery of patients is established. Moreover, popularization and simplification of the ideas of advanced mathematicians may provide an unconventional explorative platform for clinical problems.

Intravenous rt-PA in patients with ischaemic stroke and renal dysfunction

OBJECTIVE

Renal dysfunction (RD) increases risk for ischaemic stroke (IS). The impact of RD on the effects of iv-thrombolysis in the Caucasian population has not been fully determined.

AIMS

To evaluate the associations between RD and the outcome of iv-thrombolysis in Caucasian patients with IS.

METHODS

The observational, multicentre study included 404 patients with IS who were treated with iv-thrombolysis. RD was defined as estimated glomerular filtration rate ≤ 60 ml/min/1.73 m(2). Outcome was assessed with modified Rankin Score at 3 months after the stroke onset.

RESULTS

Medians baseline NIHSS score did not differ between groups of patients with and without RD (12.0 vs. 11.0 pts, p=0.33). Unfavourable outcome was found in 52.1% of patients with and in 41.2% of patients without RD (p=0.05), mortality was higher in patients with RD (29.9% vs. 14.3%, p<0.001), and the presence of haemorrhagic transformation (HT) did not differ between the groups (17.1% vs. 17.1% respectively, p=0.996). A multivariate analysis showed no impact of RD on the unfavourable outcome (OR 0.98; 95%CI 0.88-1.10), mortality (OR 0.92; 95%CI 0.81-1.05) or presence of HT (OR 1.03; 95%CI 0.90-1.18).

CONCLUSIONS

We found no impact of RD on the safety and efficacy of iv-thrombolysis in Caucasian patients with IS.

[The effect of cigarette smoking on serum activities of paraoxonase and arylesterase in stroke patients]

Cigarette smoking is one of most important modifiable risk factors of stroke. Lipids peroxidation remains crucial among pathomechanisms leading to increased risk of stroke in tobacco smokers.

AIM OF THE STUDY

To evaluate the effect of cigarette smoking on the activity of paraoxonase and arylesterase as enzymes involved in protection against oxidation of low-density lipoproteins. We have included in the study 431 subsequent stroke patients hospitalized in Department of Neurology in Poznan in a period from February 2007 to May 2008. The control group consisted of 16 healthy, nonsmoking volunteers. The activity of paraoxonase (PON) and arylesterase (ARE) in patients' sera was estimated by spectrophotometric methods. All patients admitted to emergency room underwent clinical examination. General examination, neurological examination and clinimetric assessment with the use of GCS (Glasgow Coma Scale) and NIHSS (National Institute of Health Stroke Scale) scales were performed.

RESULTS

The group of ischemic stroke patients consisted of 26.7% current smokers, 31.3%--ex-smokers, and 42% never-smokers. Among patients with hemorrhagic transformation of ischemic stroke 13.6 % actively smoked cigarettes, 22.7% were ex-smokers, and 63.7%--never-smokers. The statistical analysis of age of patients in all studied groups showed the younger onset of stroke in smokers (p < 0.0001). The activity of arylesterase was significantly disturbed by cigarette smoking in patients with ischemic stroke. In smokers with ischemic stroke ARE activity correlated negatively with number of cigarettes smoked daily (r = -0.2133; p = 0.0322). We have showed positive correlation of duration of smoking with ARE activity (r = 0.2573; p = 0.0239). In non-smoking ischemic stroke patients PON activity increased significantly (p < 0.01) comparing to controls. Tobacco smoking caused impairment of enzymatic antioxidant mechanisms related to paraoxonase activity, because there was no significant (p > 0.05) up-regulation of PON activity in smokers with ischemic stroke. The activity of arylesterase is modified by tobacco smoking in ischemic stroke patients. Smoking causes disturbances in paraoxonase--associated enzymatic antioxidant effects in ischemic stroke patients. Abnormalities of activities of antioxidant enzymes may cause earlier onset of stroke in tobacco smokers.

[The effect of tobacco smoking on clinimetric evaluation of stroke patients]

Tobacco smoking is recognized as the risk factor of stroke, however its effect on the risk of recurrent cerebrovascular events is not well clarified.

THE AIM OF THE STUDY

To evaluate the effect of tobacco smoking on results of clinimetric scoring of stroke patients and association with results of routine laboratory tests. The study included 431 stroke patients (409--ischemic stroke, 22--with hemorrhagic transformation of ischemic stroke). After admission to Emergency Room all stroke patients were examined clinically and scored according to National Institute of Health Stroke Scale (NIHSS). Then, 7 days after stroke onset NIHSS scoring was repeated and patients were scored in Rankin and GOS scales (Glasgow Outcome Scale). Everyday activity was assessed in Barthel scale 30, 90, 180 and 360 days after stroke onset. Moreover, computer tomography scans and laboratory tests were performed including hematology, glucose, fibrinogen, CRP and D-dimers concentrations. In smokers with ischemic stroke we have found trend (p = 0.0695) in decreasing of NIHSS scoring in comparison with non-smokers. The assessment in Rankin scale performed 7 days after stroke onset showed better neurological state of smokers with stroke (p < 0.01) in comparison with non-smokers and in ex-smokers with ischemic stroke (p < 0.05) comparing to non-smokers. Smokers with stroke (ischemic and with hemorrhagic transformation) had higher (p < 0.01) scoring in GOS 7 days after onset of symptoms in comparison with non-smokers. Ex-smokers with ischemic stroke had higher (p < 0.05) scores in GOS than nonsmokers. Tobacco smoking had no effect on clinimetric evaluation of patients with hemorrhagic transformation of ischemic stroke. Smoking was associated with lower levels of glucose, fibrinogen and D-dimers and higher hematocrit in ischemic stroke patients.

CONCLUSIONS

The clinical course of the early phase of ischemic stroke was benign in smokers comparing to non-smokers. Better results of clinimetric evaluation and lower mortality of smokers with ischemic stroke may be related to lower levels of glucose, fibrinogen and D-dimers. Tobacco smoking had no effect on long-term clinimetric evaluation of patients both with ischemic stroke and hemorrhagic transformation. In smokers with hemorrhagic transformation higher mortality was associated with increased D-dimers concentration.

[Association between carotid atherosclerosis, inflammatory markers and Chlamydia pneumoniae infection]

BACKGROUND AND PURPOSE

The aim of this study was to assess the correlation between morphological markers of carotid atherosclerosis, such as intima-media thickness (IMT) and the cross-sectional plaque area with markers of inflammation and C. pneumoniae infection.

MATERIAL AND METHODS

The study involved a group of 128 persons (63 females, 49.2%), including 54 atherothrombotic stroke patients. The IMT and cross-sectional plaque area of common and internal carotid arteries were measured by ultrasonography. We assessed the C-reactive protein (CRP) and fibrinogen blood level, white blood cell (WBC) count, levels of IgA and IgG antibodies against C. pneumoniae , additionally the presence of C. pneumoniae DNA in WBCs was detected by PCR. We also considered the following risk factors: hypertension, diabetes, obesity and smoking.

RESULTS

The multiple regression analysis showed the strongest and independent correlations of WBC with the IMT (r=0.32; p=0.0003) and plaque area (r=0.24; p=0.008) increase. Also other factors, such as smoking (r=0.19; p=0.026), hypertension (r=0.18; p=0.023) and CRP concentration (r=0.17; p=0.036) showed a significant correlation with carotid IMT. C. pneumoniae -specific IgG antibodies level showed a significant correlation with IMT only in the linear regression analysis, but not in the multiple regression analysis. C. pneumoniae DNA presence results did not reveal a significant correlation with either IMT or the carotid plaque area.

CONCLUSION

Inflammatory markers, especially the WBC count and CRP level, showed an independent and stronger correlation with carotid atherosclerosis than markers of C. pneumoniae infection.

Carotid intima-media thickness better differentiates between groups of stroke patients and persons without cerebrovascular disease than other conventional and novel risk factors

When measured by ultrasound, the morphological markers of carotid atherosclerosis such as intima-media thickness (IMT) and cross-sectional plaque area have been associated with the risk of ischaemic stroke. We set out to determine whether the morphological parameters of the carotid arteries made it possible to better differentiate between groups of older atherothrombotic stroke patients and persons without cerebrovascular disease than conventional and novel risk factors of stroke. Of the total number of 623 persons examined, 54 stroke patients (mean age 63.3 years) and 74 controls without cerebrovascular disease (mean age 66.3 years) fulfilled the inclusion criteria for this investigation and were enrolled in the case-control study. After adjustment for age, gender and education level, the strongest associations were found between stroke and carotid IMT [odds ratio (OR) = 10.6; 95% confidence interval (CI): 4.3-26.9] and plaque area (OR = 5.4; 95%CI: 2.3-13.1). Other risk factors showed weaker associations with stroke occurrence. Of the clinical risk factors, a significant association was found between stroke and coronary heart disease (OR = 3.5; 95%CI: 1.2-10.2), hypertension (OR = 3.2; 95%CI: 1.5-7.2) and smoking (OR = 2.7; 95%CI: 1.1-6.4). From the laboratory-derived risk factors a significant association was found between stroke and triglyceride levels (OR = 4.4; 95%CI: 1.9-10.0), and an inverse correlation was observed between stroke occurrence and HDL-cholesterol level (OR = 0.4; 95%CI: 0.2-0.8). The carotid IMT and plaque area, measured with the use of ultrasonography, showed a better correlation with stroke occurrence than currently recognised clinical and biochemical risk factors. The intima-media thickness and plaque area of the carotid arteries could be useful parameters in the development of strategies to identify patients at high risk of atherothrombotic ischaemic stroke.

Autoantibodies AgainstN-Homocysteinylated Proteins in Humans

BACKGROUND AND PURPOSE

Homocysteine (Hcy)-thiolactone mediates protein N-homocysteinylation in humans. Protein N-linked Hcy comprises a major pool of Hcy in human blood, greater that the "total" Hcy pool. N-homocysteinylated proteins are structurally different, compared with native proteins, and are thus likely to be recognized as neoself antigens and induce an autoimmune response. This study was undertaken to provide evidence for anti-Nepsilon-Hcy-Lys-protein antibody and to examine associations between the antibody level, Hcy, and stroke in humans.

METHODS

ELISA was used to quantify anti-Nepsilon-Hcy-Lys-protein antibodies in human serum.

RESULTS

We found that autoantibodies that specifically recognize Nepsilon-Hcy-Lys epitope on Hcy-containing proteins occur in humans. Serum levels of anti-Nepsilon-Hcy-Lys-protein autoantibodies positively correlate with plasma total Hcy levels, but not with plasma cysteine or methionine levels. In a group of exclusively male patients with stroke, mean level of anti-Nepsilon-Hcy-Lys-protein autoantibodies was approximately 50% higher than in a group of healthy subjects.

CONCLUSIONS

These findings support a hypothesis that Nepsilon-Hcy-Lys-protein is a neoself antigen, which may contribute to immune activation, an important modulator of atherogenesis.

Association of influenza incidence with multiple sclerosis onset

The aim of this study was to investigate the environmental factors influencing the tangible changes in the incidence of multiple sclerosis (MS) over a period of the past 30 years in the town Gniezno, Poland. We analysed many environmental factors to which the whole population was exposed in the respective period. The following factors were considered: viral infections (influenza, measles, varicella, rubella, mumps), atmospheric air pollution and climate conditions. A positive correlation has been found between the incidence of influenza and the incidence of MS in the same year (r = 0.37; p = 0.04) as well as with the MS incidence assessed after 5 years (r = 0.64; p = 0.0005). No significant correlation has been found between the incidence of MS and other investigated environmental factors. These results support the hypothesis that influenza infection could precipitate MS onset.

An evaluation of the reproducibility of the measurement of the intima-media thickness of carotid arteries

The intima-media thickness (IMT) of carotid arteries was demonstrated to be a reliable measure for early stages of atherosclerosis. B-mode ultrasound may be used to measure carotid IMT. The measurements of the IMT of the carotid artery (CA) conducted by different investigators can be comparable and enable the implementation of clinical trial successfully while maintaining a high reproducibility value. The objective of the study was to evaluate the reproducibility of the measurements made by the same investigator on two separate occasions (intraobserver variability) and the reproducibility of the off-line measurements between four sonographers in our laboratory (interobserver variability). The IMT of CA in 25 subjects (15 post stroke and 10 healthy persons) was investigated with the use of high-resolution ultrasonography. The CA subdivided into the common, bulbs and internal segments were scanned twice with a 3-week interval. Additionally three other readers with different levels of experience and skills in ultrasonography were asked to perform the same measurements in duplicate with at least a 3-week interval between. A high concurrence for intraobserver variability was detected with a correlation coefficient ranging from 0.92 to 0.95; p < 0.0001, and maximal bias 0.019 mm. Interobserver variability for all four readers also demonstrated a high correlation coefficient ranging from 0.72 to 0.83; p < 0.0001, and the maximal bias of measurements did not exceed 0.08 mm. The analogue measurements performed by the team demonstrate a reliable reproducibility in terms of the results of morphologic measurements. The differences obtained in the study were less than the error of the method (i.e. 0.1 mm) and should not influence clinical decision-making. Additionally, this study demonstrated that interobserver concurrence increases with the increasing experience of the investigators.

[Biomechanic shear stress in carotid arteries and atherosclerosis development]

One of the major hemodynamic forces acting on blood vessels is shear stress, which is, the friction force between the endothelial cell surface and flowing blood. Arterial shear stress within physiologic range (15-70 dyne/cm2) induces endothelial quiescence and an atheroprotective gene expression profile. Low shear stress (< 4 dyne/cm2) stimulates atherogenic phenotype, whereas, high shear stress (> 70 dyne/cm2) induce prothrombotic state.

Serum autoantibodies to actin are associated with carotid artery wall adventitial thickness assessed using B-mode ultrasound

Atherosclerosis, as a chronic inflammatory condition, can be mediated by immunological reactions. Therefore, it is possibly related to a specific antigen. Because autoimmunological reactions occur during atherogenesis, it is possible that alpha-actin expression induces a specific autoimmune reaction. We determined whether the intima-media (IMT) and adventitial thickness (AT) of carotid arteries, assessed by an ultrasound method, correlate with the level of anti-actin autoantibodies (AAA) in human serum. The study involved a group of 128 patients (66 women and 62 men). The mean age was 65.0 (+/- 7.9) years. Fifty-four patients had suffered an ischaemic stroke, whereas the remaining (as controls) had no history of cerebrovascular disease. High-resolution ultrasonography was used to evaluate the IMT and AT of their common carotid arteries. The mean carotid IMT was 0.95 (+/- 0.36) mm and the mean AT was 0.94 (+/- 0.20) mm. There was a significant correlation between carotid AT and the AAA serum level (r = 0.20; p = 0.024). However, there was no association between the mean IMT and AAA serum levels in the carotid arteries (r = 0.08; p = 0.328). In this preliminary (in vivo) study, we found that the level of AAA correlated positively with ultrasonographically assessed AT during carotid atherosclerosis.

[Relationship between the concentration of antibodies to myosin heavy chains in serum and symptomatic carotid atherosclerosis]

It is believed that atherosclerosis could result from inflammatory-fibroproliferative response to various forms of injury of endothelium and smooth muscle cells of arterial wall. The aim of this study was to examine whether immunological reaction against myosin filaments of carotid artery (CA) wall smooth muscle cells is involved in atherogenesis. 43 patients (22 females) with first-ever ischaemic stroke proven by CT were investigated. The results were compared with those obtained in 40 (21 females) healthy sex- and age-matched subjects. Anti-myosin antibodies (AMA) were evaluated by solid phase radioimmunoassay using rabbit myosin heavy chains as an antigen. The intima-media thickness (IMT) of common and CA--a measure for atherosclerosis--was estimated with the use of high-resolution ultrasonography. The AMA serum concentration in stroke patients was significantly greater than in control subjects (p < 0.001). Mean IMT for CA in stroke patients was significantly increased compared with the controls (0.98 +/- 0.17 mm vs. 0.68 +/- 0.13 mm; p < 0.0001). There was a significant correlation between AMA serum antibodies concentration and IMT (r = 0.51; p < 0.001).

CONCLUSION

The significant correlation between AMA concentration and IMT of CA is the basis of the hypothesis that immunological reaction against myosin heavy chains of smooth muscle cells in CA is involved in atherogenesis.

[Effect of Chlamydia pneumoniae infection on carotid atherosclerosis development]

Recently, a growing number of epidemiological, histopathological and microbiological studies have shown that chronic Chlamydia pneumoniae (C. pneumoniae) infection accelerates the progression of atherosclerosis of carotid and cerebral arteries and thus could constitute a risk factor for stroke. We present a number of mechanisms postulated in recent papers that link C. pneumoniae infection with the development of atherosclerosis. The one most important seems to be the effect of activation of nuclear factor--kappa B and the phenomenon of antigenic mimicry between human and C. pneumoniae heat shock proteins. We also discuss the problem of immunological reaction against myosin filaments of carotid artery wall smooth muscle cells and the problem of antigenic mimicry between heavy chains of myosin filaments and antigens presented on C. pneumoniae outer membrane.

[Leukocytosis in the first day of acute ischemic stroke as a prognostic factor of disease progression]

It has been reported that white blood cells (WBC) may contribute to the initiation and further development of stroke. WBC count could have influence on hemorheology, thrombosis and induction of vasoconstriction in cerebral arteries. The aim of this work was to determine whether WBC count assessed in patients with acute stroke in the first day of the disease have a predictive value for the late clinical outcomes. Peripheral WBC count was measured at the admission to the hospital in 100 consecutive patients with acute stroke. Ischemic stroke was confirmed in all patients by head CT. Neurological status was evaluated with the use of modified Rankin's Scale. We assessed the following clinical outcomes: in-hospital mortality, the lack of neurological improvement on the 21st day of disease, and the need for hospital stay longer than 21 days. Odds ratio (OR) with 95% confidence interval (95% CI) adjusted for patient's age, gender, cardiovascular diseases, diabetes mellitus and previous stroke was calculated with the use of logistic regression. OR was evaluated both for the presence of WBC count > 10.000 cells/microliter and for each 1000 leukocytes/microliter increase. WBC count greater than 10.000 cells/microliter was associated with a more than seventy-fold greater risk for death (OR--75.18; 95% CI: 8.89-635.84; p = 0.0001), nearly eight times increased risk for the no-improvement status (OR--7.78; 95% CI: 2.51-24.17; p = 0.0004) and approximately four times increased risk for the prolonged hospital stay (OR--4.20; 95% CI: 1.50-11.72; p = 0.0062). Each 1000 cell/microliter increase in WBC count at the admission was associated with increased risk for in-hospital mortality (OR--2.24; 95% CI: 1.39-3.57; p = 0.0008), no neurological improvement (OR--1.43; 95% CI: 1.15-1.76; p = 0.0009) and the need for prolonged hospitalization (OR--1.26; 95% CI: 1.07-1.49; p = 0.0066). Increased WBC count within the first 12 hours of stroke is an independent and strong risk factor for mortality, no neurological improvement, and the need for prolonged hospitalization in the course of acute ischemic stroke.

[Infection as a likely risk factor for ischemic stroke]

This review presents recent informations concerning the role of viral and bacterial (especially Helicobacter pylori and Chlamydia pneumoniae) infections in the development of ischaemic stroke. Among possible pathogenic pathways that link infections and stroke, the special attention is paid to the coagulation abnormalities and immunological reactions.

[Intima-media complex thickness of common carotid artery as a risk factor for stroke]

Intima-Media Thickness (IMT) of Common Carotid Artery (CCA) could be seen as the atherosclerotic risk factors' final morphological effect. We investigated the hypothesis that IMT of CCA is significantly different in sex- and age-matched groups of persons with stroke and healthy subjects. 47 patients with first-ever atherothrombotic stroke proven by CT were investigated. Patients with atrial fibrillation, valvular heart disease and left ventricular hyperthrophy were excluded. The IMT of CCA were estimated by High-Resolution B-Mode Ultrasonography. All the patients had bilateral IMT measurement within 20 mm proximal to the carotid bulb on the far wall in the anterioposterior and laterolateral plane. The results were compared with those obtained in 50 healthy sex- and age-matched subjects. We found a strong association between IMT and stroke (p < 0.0001). Mean IMT was 0.96 mm (SD 0.18) in patients and 0.70 mm (SD 0.09) in controls. The presence of atherosclerotic plaques was 0.34 and 0.08 for patients and controls respectively (p = 0.0025). IMT of CCA is strongly positively associated with the risk for stroke. The frequency of atherosclerotic plaques in CCAs is statistically significantly higher in stroke patients than in control group.