Executive function subdomains are associated with post-stroke functional outcome and permanent institutionalization.

BACKGROUND AND PURPOSE: Impairment of executive functions (EFs) is a common cognitive symptom post-stroke and affects independence in daily activities. Previous studies have often relied on brief cognitive tests not fully considering the wide spectrum of EF subdomains. A detailed assessment of EFs was used to examine which of the subdomains and tests have the strongest predictive value on post-stroke functional outcome and institutionalization in long-term follow-up. METHODS: A subsample of 62 patients from the Helsinki Stroke Aging Memory Study was evaluated with a battery of seven neuropsychological EF tests 3 months post-stroke and compared to 39 healthy control subjects. Functional impairment was evaluated with the modified Rankin Scale (mRS) and Instrumental Activities of Daily Living (IADL) scale at 3 months, and with the mRS at 15 months post-stroke. Institutionalization was reviewed from the national registers of permanent hospital admissions in up to 21-year follow-up. RESULTS: The stroke group performed more poorly than the control group in multiple EF tests. Tests of inhibition, set shifting, initiation, strategy formation and processing speed were associated with the mRS and IADL scale in stroke patients. EF subdomain scores of inhibition, set shifting and processing speed were associated with functional outcome. In addition, inhibition was associated with the risk for earlier institutionalization. CONCLUSIONS: Executive function was strongly associated with post-stroke functional impairment. In follow-up, poor inhibition was related to earlier permanent institutionalization. The results suggest the prognostic value of EF subdomains after stroke.

Ultra-acute diagnostics for stroke: Large-scale implementation of prehospital biomarker sampling.

OBJECTIVES: Blood-based biomarkers could enable early and cost-effective diagnostics for acute stroke patients in the prehospital setting to support early initiation of treatments. To facilitate development of ultra-acute biomarkers, we set out to implement large-scale prehospital blood sampling and determine feasibility and diagnostic timesavings of this approach. MATERIALS AND METHODS: Emergency medical services (EMS) personnel of the Helsinki metropolitan area were trained to collect prehospital blood samples from thrombolysis candidates using a cannula adapter technique. Time delays, sample quality, and logistics were investigated between May 20, 2013 and May 19, 2014. RESULTS: Prehospital blood sampling and study recruiting were successfully performed for 430 thrombolysis candidates, of which 50% had ischemic stroke, 14.4% TIA, 13.5% hemorrhagic stroke, and 22.1% stroke mimics. A total of 66.3% of all samples were collected during non-office hours. The median (interquartile range) emergency call to prehospital sample time was 33 minutes (25-41), and the median time from reported symptom onset or wake-up to prehospital sample was 53 minutes (38-85; n=394). Prehospital sampling was performed 31 minutes (25-42) earlier than hospital admission blood sampling and 37 minutes (30-47) earlier than admission neuroimaging. Hemolysis rate in serum and plasma samples was 6.5% and 9.3% for EMS samples, and 0.7% and 1.6% for admission samples. CONCLUSIONS: Prehospital biomarker sampling can be implemented in all EMS units and provides a median timesaving of more than 30 minutes to first blood sample. Large prehospital sample sets will enable development of novel ambulance biomarkers to improve early differential diagnosis and treatment of thrombolysis candidates.

Prognostic significance of proteinuria in stroke patients treated with intravenous thrombolysis.

BACKGROUND AND PURPOSE: Proteinuria and estimated glomerular filtration rate (eGFR) are indicators of renal function. Whether proteinuria better predicts outcome than eGFR in stroke patients treated with intravenous thrombolysis (IVT) remains to be determined. METHODS: In this explorative multicenter IVT register based study, the presence of urine dipstick proteinuria (yes/no), reduced eGFR (<60 ml/min/1.73 m2 ) and the coexistence of both with regard to (i) poor 3-month outcome (modified Rankin Scale score 3-6), (ii) death within 3 months and (iii) symptomatic intracranial hemorrhage (ECASS-II criteria) were compared. Unadjusted and adjusted odds ratios (ORs) with 95% confidence intervals were calculated. RESULTS: Amongst 3398 patients, 881 (26.1%) had proteinuria and 623 (18.3%) reduced eGFR. Proteinuria [ORadjusted 1.65 (1.37-2.00) and ORadjusted 1.52 (1.24-1.88)] and reduced eGFR [ORadjusted 1.26 (1.01-1.57) and ORadjusted 1.34 (1.06-1.69)] were independently associated with poor functional outcome and death, respectively. After adding both renal markers to the models, proteinuria [ORadjusted+eGFR 1.59 (1.31-1.93)] still predicted poor outcome whilst reduced eGFR [ORadjusted+proteinuria 1.20 (0.96-1.50)] did not. Proteinuria was associated with symptomatic intracranial hemorrhage [ORadjusted 1.54 (1.09-2.17)] but not reduced eGFR [ORadjusted 0.96 (0.63-1.62)]. In 234 (6.9%) patients, proteinuria and reduced eGFR were coexistent. Such patients were at the highest risk of poor outcome [ORadjusted 2.16 (1.54-3.03)] and death [ORadjusted 2.55 (1.69-3.84)]. CONCLUSION: Proteinuria and reduced eGFR were each independently associated with poor outcome and death but the statistically strongest association appeared for proteinuria. Patients with coexistent proteinuria and reduced eGFR were at the highest risk of poor outcome and death.

Symptomatic post-thrombolytic intracerebral hemorrhage is not related to the cause of stroke.

BACKGROUND AND PURPOSE: The development of intracerebral hemorrhage following intravenous thrombolysis (IVT) can be influenced by various confounders related to the underlying vessel and tissue conditions. There are some data on association of cause of the stroke and the hemorrhage transformation. We tested the hypothesis that the cause of stroke is associated with the development of symptomatic intracerebral hemorrhage (sICH) following IVT. METHODS: A consecutive cohort of 2485 IVT-treated patients at the Helsinki University Central Hospital was classified according to the Trial of ORG 10172 in Acute Stroke Treatment (TOAST) criteria. An sICH was classified according to the European Cooperative Acute Stroke Study II criteria. The associations of sICH with nominal, ordinal and continuous variables were analyzed in a univariate binary regression model and adjusted in multivariate binary regression models. RESULTS: In univariate analyses, cardioembolism [odds ratio (OR), 1.14; 95% confidence interval (CI), 0.79-1.64] and large-artery atherosclerosis (OR, 1.30; 95% CI, 0.85-2.00) were not associated with sICH, and small-vessel occlusion was associated with lower odds for sICH (OR, 0.18; 95% CI, 0.06-0.57). When adjusted for previously identified factors associated with sICH, none of the TOAST categories was associated with a higher or lower frequency of sICH. CONCLUSIONS: The development of sICH in IVT-treated patients is not related to the cause of stroke.

Post-thrombolytic blood pressure and symptomatic intracerebral hemorrhage.

BACKGROUND AND PURPOSE: Most guidelines for intravenous thrombolysis (IVT) in acute ischaemic stroke patients advise keeping systolic blood pressure (BP) below 180/105 mmHg prior to the bolus injection. Less is known about optimal management of BP thereafter. We assessed temporal changes in post-thrombolytic systolic BP values and their impact on development of symptomatic intracerebral hemorrhage (sICH). METHODS: The study cohort included 1868 consecutive acute ischaemic stroke patients treated with IVT at the Helsinki University Central Hospital. sICH was defined according to the European Cooperative Acute Stroke Study II (ECASS-II) (primary outcome), National Institute of Neurological Disorders and Stroke, and Safe Implementation of Thrombolysis in Stroke criteria. We evaluated BP at admission, prior to IVT and at 2, 4, 8, 12, 24 and 48 h after thrombolysis. We used univariate and multivariable models to test the effect of BP at various time-points on development of post-thrombolytic sICH. RESULTS: Prevalence of sICH in the cohort was 5.8% (ECASS-II). Patients with sICH had significantly higher systolic BP at several time-points after IVT compared with those without sICH (P < 0.01 at 2 and 4 h; P < 0.05 at 12 and 48 h). The odds ratios for development of sICH per 10 mmHg increase in BP were 1.14 [95% confidence interval (CI), 1.03-1.25], 1.14 (95% CI, 1.03-1.25), 1.12 (95% CI, 1.01-1.23) and 1.12 (95% CI, 1.01-1.23), respectively. At 8 h, we observed a trend (P = 0.07) for ECASS-II and a significant effect (P < 0.05) for National Institute of Neurological Disorders and Stroke, and Safe Implementation of Thrombolysis in Stroke criteria. Thus, the only time-point with no difference observed was 24 h. CONCLUSIONS: Patients with post-thrombolytic sICH have significantly higher systolic BP at several time-points compared with patients without sICH.

Extensive white matter changes predict stroke recurrence up to 5 years after a first-ever ischemic stroke.

BACKGROUND: White matter changes (WMCs), a surrogate for small-vessel disease (SVD), have been shown to be associated with a major negative influence on cognition, mood and functioning in daily life. We aimed to investigate whether severe WMCs are a risk factor for recurrent ischemic stroke in a long-term follow-up. METHODS: 320 consecutive patients admitted to hospital with a first-ever ischemic stroke were included in the study and followed up for 12 years using extensive national registers. Patients were aged between 55 and 85 years, with a mean age of 70.8 years. WMCs were rated using MRI and stratified into two grades: absent to moderate WMCs versus severe WMCs. Univariate analysis was performed using binary logistic regression analysis, Kaplan-Meier log rank analysis and life table function. To control for factors such as age, education and cardiovascular risk factors, a multivariate Cox regression proportional hazards analysis was made with forced entry. RESULTS: At least one recurrent stroke, nonfatal or fatal, was diagnosed in 76 (23.8%) patients at 5 years and in 127 (39.7%) patients at 12 years. In univariate analysis, only advancing age was associated with WMCs. The cumulative 5-year recurrence risk was 24.5% [95% confidence interval (95% CI) 23.8-25.2] for patients with absent to moderate WMCs and 39.1% (95% CI 38.1-40.1) for patients with severe WMCs. The cumulative 12-year recurrence risk was 48.1% (95% CI 45.5-50.7) for patients with absent to moderate WMCs and 60.9% (95% CI 56.7-65.1) for patients with severe WMCs. In Cox regression proportional hazards analysis, independent predictors of recurrent stroke at 5 years were severe WMCs [hazard ratio (HR) 1.80, 95% CI 1.11-2.95], atrial fibrillation (HR 1.81, 95% CI 1.09-3.02), hypertension (HR 1.69, 95% CI 1.05-2.71) and peripheral arterial disease (HR 1.89, 95% CI 1.06-3.38). At 12 years, only increasing age remained as an independent predictor (HR 1.04, 95% CI 1.02-1.07). In receiver operating characteristic analysis, the area under the curve for severe WMCs was 0.58 (95% CI 0.51-0.65) for the prediction of stroke recurrence within 5 years. CONCLUSIONS: In our well-defined cohort of poststroke patients, the presence of severe WMCs was an indicator of stroke recurrence up to 5 years after a first-ever ischemic stroke. WMCs can be considered as an SVD marker that summarizes the effects of several classical risk factors on the small-vessel brain network and therefore can be used as a score for risk stratification of stroke recurrence. Our findings further underline the poor long-term prognosis of cerebral SVD.