To Örebro University

BACKGROUND AND PURPOSE: Anticoagulant treatment is effective for preventing recurrent ischemic strokes in patients who have atrial fibrillation. This benefit is paid by a small increase of hemorrhages. Anticoagulant-related hemorrhages seem to increase with age, but there are few studies showing whether the benefits of treatment persist in old age.

METHODS: For this observational study, 4 different registers were used, among them Riksstroke, the Swedish Stroke Register. Patients who have had a recent ischemic stroke, were 80 to 100 years of age, and had atrial fibrillation, were included from 2006 through 2013. The patients were stratified into 3 age groups: 80 to 84, 85 to 89, and ≥90 years of age. Information on stroke severity, risk factors, drugs, and comorbidities was gathered from the registers. The patients were followed with respect to ischemic or hemorrhagic stroke, other hemorrhages, or death.

RESULTS: Of all 23 356 patients with atrial fibrillation, 6361 (27%) used anticoagulants after an ischemic stroke. Anticoagulant treatment was associated with less recurrent ischemic stroke in all age groups. Hemorrhages increased most in the ≥90-year age group, but this did not offset the overall beneficial effect of the anticoagulant. Apart from age, no other cardiovascular risk factor or comorbidity was identified that influenced the risk of anticoagulant-associated hemorrhage. Drugs other than anticoagulants did not influence the incidence of major hemorrhage.

CONCLUSIONS: Given the patient characteristics in this study, there is room for more patients to be treated with anticoagulants, without hemorrhages to prevail. In nonagenarians, hemorrhages increased somewhat more, but this did not affect the overall outcome in this age stratum.

Background and purpose: Physical and psychological characteristics in adolescence are associated with subsequent stroke risk. Our aim is to investigate their relevance to length of hospital stay and risk of second stroke.

Methods: Swedish men born between 1952 and 1956 (n=237 879) were followed from 1987 to 2010 using information from population-based national registers. Stress resilience, body mass index, cognitive function, physical fitness, and blood pressure were measured at compulsory military conscription examinations in late adolescence. Joint Cox proportional hazards models estimated the associations of these characteristics with long compared with short duration of stroke-related hospital stay and with second stroke compared with first.

Results: Some 3000 men were diagnosed with nonfatal stroke between ages 31 and 58 years. Low stress resilience, underweight, and higher systolic blood pressure (per 1-mm Hg increase) during adolescence were associated with longer hospital stay (compared with shorter) in ischemic stroke, with adjusted relative hazard ratios (and 95% confidence intervals) of 1.46 (1.08-1.89), 1.41 (1.04-1.91), and 1.01 (1.00-1.02), respectively. Elevated systolic and diastolic blood pressures during adolescence were associated with longer hospital stay in men with intracerebral hemorrhage: 1.01 (1.00-1.03) and 1.02 (1.00-1.04), respectively. Among both stroke types, obesity in adolescence conferred an increased risk of second stroke: 2.06 (1.21-3.45).

Conclusions: Some characteristics relevant to length of stroke-related hospital stay and risk of second stroke are already present in adolescence. Early lifestyle influences are of importance not only to stroke risk by middle age but also to recurrence and use of healthcare resources among stroke survivors.

BACKGROUND AND PURPOSE: Early initiated treatment of stroke increases the chances of a good recovery. This randomized controlled study evaluates how an increased priority level for patients with stroke, from level 2 to 1, from the Emergency Medical Communication Center influences thrombolysis frequency, time to stroke unit, and whether other medical emergencies reported negative consequences.

METHODS: Patients aged 18 to 85 years in Stockholm, Sweden, with symptoms of stroke within 6 hours were randomized from the Emergency Medical Communication Center or emergency medical services to an intervention group, priority level 1, immediate call of an ambulance, or to a control group with standard priority level, that is, priority level 2 (within 30 minutes). Before study start, an educational program on identification of stroke and importance of early initiated treatment was directed to all medical dispatchers and ambulance and emergency department personnel.

RESULTS: During 2008, 942 patients were randomized of which 53% (n=496) had a final stroke/transient ischemic attack diagnosis. Patients in the Emergency Medical Communication Center randomized intervention group reached the stroke unit 26 minutes earlier than the control group (P<0.001) after the emergency call. Thrombolysis was given to 24% of the patients in the intervention group compared with 10% of the control subjects (P<0.001). The higher priority level showed no negative effect on other critical ill patients requiring priority level 1 prehospital attention.

CONCLUSIONS: This randomized study shows negligible harm to other medical emergencies, a significant increase in thrombolysis frequency, and a shorter time to the stroke unit for patients with stroke upgraded to priority level 1 from the Emergency Medical Communication Center and through the acute chain of stroke care.

BACKGROUND AND PURPOSE: Previous studies of stroke management and outcome in Sweden have revealed differences between men and women. We aimed to analyze if differences in stroke incidence, care, and outcome have altered over time.

METHODS: All stroke events registered in the Swedish Stroke Register 2005 to 2018 were included. Background variables and treatment were collected during the acute hospital stay. Survival data were obtained from the national cause of death register by individual linkage. We used unadjusted proportions and estimated age-adjusted marginal means, using a generalized linear model, to present outcome.

RESULTS: We identified 335 183 stroke events and a decreasing incidence in men and women 2005 to 2018. Men were on average younger than women (73.3 versus 78.1 years) at stroke onset. The age-adjusted proportion of reperfusion therapy 2005 to 2018 increased more rapidly in women than in men (2.3%-15.1% in men versus 1.4%-16.9% in women), but in 2018, women still had a lower probability of receiving thrombolysis within 30 minutes. Among patients with atrial fibrillation, oral anticoagulants at discharge increased more rapidly in women (31.2%-78.6% in men versus 26.7%-81.9% in women). Statins remained higher in men (36.9%-83.7% in men versus 32.3%-81.2% in women). Men had better functional outcome and survival after stroke. After adjustment for women's higher age, more severe strokes, and background characteristics, the absolute difference in functional outcome was <1% and survival did not differ.

CONCLUSIONS: Stroke incidence, care, and outcome show continuous improvements in Sweden, and previously reported differences between men and women become less evident. More severe strokes and older age in women at stroke onset are explanations to persisting differences.

Background and Purpose: The purpose of this study was to investigate the impact of improved antithrombotic treatment in atrial fibrillation after the introduction of non-vitamin K antagonist oral anticoagulants on the incidence of stroke and bleeding in a real-life total population, including both primary and secondary care.

Methods: All resident and alive patients with a recorded diagnosis for atrial fibrillation during the preceding 5 years in the Stockholm County Healthcare database (Vårdanalysdatabasen) were followed for clinical outcomes during 2012 (n=41 008) and 2017 (n=49 510).

Results: Pharmacy claims for oral anticoagulants increased from 51.6% to 73.8% (78.7% among those with CHA₂DS₂-VASc ≥2). Non-vitamin K antagonist oral anticoagulant claims increased from 0.4% to 34.4%. Ischemic stroke incidence rates decreased from 2.01 per 100 person-years in 2012 to 1.17 in 2017 (incidence rate ratio, 0.58; 95% CI, 0.52-0.65). The largest increases in oral anticoagulants use and decreases in ischemic strokes were seen in patients aged ≥80 years who had the highest risk of stroke and bleeding. The incidence rates for major bleeding (2.59) remained unchanged (incidence rate ratio, 1.00; 95% CI, 0.92-1.09) even in those with a high bleeding risk. Poisson regression showed that 10% of the absolute ischemic stroke reduction was associated with increased oral anticoagulants treatment, whereas 27% was related to a generally decreased risk for all stroke.

Conclusions: Increased oral anticoagulants use contributed to a marked reduction of ischemic strokes without increasing bleeding rates between 2012 and 2017. The largest stroke reduction was seen in elderly patients with the highest risks for stroke and bleeding. These findings strongly support the adoption of current guideline recommendations for stroke prevention in atrial fibrillation in both primary and secondary care.

BACKGROUND AND PURPOSE: The Stockholm Stroke Triage System (SSTS) is a prehospital algorithm for detection of endovascular thrombectomy (EVT)-eligible patients, combining symptom severity assessment and ambulance-to-hospital teleconsultation, leading to a decision on primary stroke center bypass. In the Stockholm Region (6 primary stroke centers, 1 EVT center), SSTS implementation in October 2017 reduced onset-to-EVT time by 69 minutes. We compared clinical outcomes before and after implementation of SSTS in an observational study.

METHODS: We prospectively recruited patients transported by Code Stroke ambulance within the Stockholm region under the SSTS, treated with EVT during October 2017 to October 2019, and compared to EVT patients from 2 previous years.

OUTCOMES: shift in modified Rankin Scale (mRS) scores, mRS score 0 to 1, mRS score 0 to 2, and death (all 3 months), National Institutes of Health Stroke Scale (NIHSS) score change 24-hour post-EVT, recanalization (Thrombolysis in Cerebral Infarction 2b-3), and symptomatic intracranial hemorrhage. mRS outcomes were adjusted for age and baseline NIHSS.

RESULTS: Patients with EVT in the SSTS group (n=244) were older and had higher baseline NIHSS versus historical controls (n=187): median age 74 (interquartile range, 63-81) versus 71 (61-78); NIHSS score 17 (11.5-21) versus 15 (10-20). During SSTS, median onset-to-puncture time was 136 versus 205 minutes (P<0.001). Adjusted common odds ratio for lower mRS in SSTS patients was 1.7 (95% CI, 1.2-2.3) versus controls. During SSTS, 83/240 (34.6%) versus 44/186 (23.7%) reached 3-month mRS score 0 to 1 (P=0.014), adjusted common odds ratio 2.3 (95% CI, 1.4-3.6). Median NIHSS change 24-hour post-EVT was 6 versus 4 (P=0.005). Differences in Thrombolysis in Cerebral Infarction, symptomatic intracranial hemorrhage, and death were nonsignificant.

CONCLUSIONS: With an onset to arterial puncture time reduction by 69 minutes, outcomes in thrombectomy-treated patients improved significantly after region-wide large artery occlusion triage system implementation. These results warrant replication studies in other geographic and organizational circumstances.

BACKGROUND AND PURPOSE: Recanalization status after intravenous thrombolysis (IVT) in patients with ischemic stroke is a reference point to proceed with a rescue reperfusion intervention, although early neurological improvement (NI) may preclude endovascular procedures. We aimed to evaluate the importance of restoration of blood flow at the arterial occlusion site in subgroups of patients with stroke stratified by early NI after IVT.

METHODS: The following patients were recruited from the Safe Implementation of Treatment in Stroke-International Stroke Thrombolysis Register: (1) with baseline vessel occlusion documented by computed tomographic (CT) or magnetic resonance (MR) angiography and follow-up angioimaging between 22 and 36 hours after IVT available; and (2) with dense cerebral artery sign on admission CT scan and results of follow-up CT reported. Recanalization at 24 hours was defined as absence of vessel occlusion or as resolution of dense cerebral artery sign on follow-up 22- to 36-hour imaging. NI was assessed at 2 hours and 24 hours after IVT and was defined as improvement by 20% from baseline National Institute of Health Stroke scale score. Primary outcome measure was independence, defined as modified Rankin scale score 0 to 2 after 3 months.

RESULTS: Of 28136 cases registered between December 2003 and November 2009, 5324 cases (19%) met the inclusion criteria. Patients with both NI at 2 hours post-treatment and vessel recanalization had the best chances to achieve independence at 3 months (adjusted odds ratio, 15.8; 95% confidence interval, 12.5-20.0), followed by those who had NI despite persistent occlusion (adjusted odds ratio, 4.7; 95% confidence interval, 3.6-6.1); and those without NI despite recanalization (adjusted odds ratio, 2.7; 95% confidence interval, 2.2-3.3).

CONCLUSIONS: Recanalization of an occluded artery in acute stroke is associated with favorable functional outcome both in patients with and without NI after IVT. In future evaluations of mechanical thrombectomy and other additional strategies, recanalization should be considered in patients with persisting occlusion after IVT even after significant NI.

BACKGROUND AND PURPOSE: Early carotid surgery or stenting after thrombolytic treatment for stroke has become more common during recent years. It is unclear whether this carries an increased risk of postoperative complications and death. The aim of this nationwide population-based study was, therefore, to investigate the safety of urgently performed carotid procedures in patients treated with thrombolysis for stroke.

METHODS: Using the national Vascular and Stroke registries, we identified 3998 patients who had undergone carotid endarterectomy or carotid artery stenting for symptomatic carotid stenosis between May 2008 and December 2012. Among these, 2% (79 of 3998) had undergone previous thrombolysis for stroke. We conducted a retrospective review of registry data and individual case records with regard to postoperative complications, including surgical-site bleeding, stroke, and death. The outcome was compared with the results for the remaining patient cohort (3919 of 3998) undergoing carotid surgery and stenting during the study period.

RESULTS: The median time between thrombolysis and the carotid procedure was 10 days. Seventy-one patients underwent carotid endarterectomy, and 6 patients underwent carotid artery stenting. The 30-day death and stroke rate for the thrombolysis cohort was 2.5% (2 of 79), and for the whole cohort, it was 3.8% (139 of 3626; P=0.55). The postoperative bleeding rates requiring reoperation were not significantly different between the groups (3.8% [3 of 79] in the thrombolysis group versus 3.3% [119 of 3626] in the whole cohort; P=0.79). There was no correlation between time from lysis to surgery or stenting and complications at 30 days postoperatively.

CONCLUSIONS: Urgent carotid endarterectomy or carotid artery stenting after thrombolysis for stroke may be safe without increased risk of serious complications.

BACKGROUND: There is a well-known association between low socioeconomic status (SES), poor survival, and clinician-reported outcomes after stroke. We aimed to assess socioeconomic differences in Patient Reported Outcome Measures 3 months after stroke.

METHODS: This nationwide cohort study included patients registered with acute stroke in the Swedish Stroke Register 2015-2017. Patient Reported Outcome Measures included activities of daily living (mobility, toileting, and dressing), and poststroke symptoms (low mood, fatigue, pain, and poor general health). Information on SES prestroke was retrieved from Statistics Sweden and defined by a composite measure based on education and income tertiles. Associations between SES and Patient Reported Outcome Measures were analyzed using logistic regression adjusting for confounders (sex and age) and additionally for potential mediators (stroke type, severity, cardiovascular disease risk factors, and living alone). Subgroup analyses were performed for stroke type, men and women, and younger and older patients.

RESULTS: The study included 44 511 patients. Of these, 31.1% required assistance with mobility, 18% with toileting, and 22.2% with dressing 3 months after stroke. For poststroke symptoms, 12.3% reported low mood, 39.1% fatigue, and 22.7% pain often/constantly, while 21.4% rated their general health as poor/very poor. Adjusted for confounders, the odds of needing assistance with activities of daily living were highest for patients with low income and primary school education, for example, for mobility, odds ratio was 2.06 (95% CI, 1.89-2.24) compared with patients with high income and university education. For poststroke symptoms, odds of poor outcome were highest for patients with low income and university education (eg, odds ratio, 1.79 [95% CI, 1.49-2.15] for low mood). Adjustments for potential mediators attenuated but did not remove associations. The associations were similar in ischemic and hemorrhagic strokes and more pronounced in men and patients <65 years old.

CONCLUSIONS: There are substantial SES-related differences in Patient Reported Outcome Measures poststroke. The more severe outcome associated with low SES is more pronounced in men and in patients of working age.

BACKGROUND AND PURPOSE: Intracerebral hemorrhage after treatment with intravenous recombinant tissue-type plasminogen activator for ischemic stroke can occur in local relation to the infarct, as well as in brain areas remote from infarcted tissue. We aimed to describe risk factors, 3-month mortality, and functional outcome in patients with the poorly understood complication of remote intracerebral hemorrhage, as well as local intracerebral hemorrhage.

METHODS: In this study, 43 494 patients treated with intravenous recombinant tissue-type plasminogen activator, with complete imaging data, were enrolled in the Safe Implementation of Treatments in Stroke-International Stroke Thrombolysis Register (SITS-ISTR) during 2002 to 2011. Baseline data were compared among 970 patients (2.2%) with remote parenchymal hemorrhage (PHr), 2325 (5.3%) with PH, 438 (1.0%) with both PH and PHr, and 39 761 (91.4%) without PH or PHr. Independent risk factors for all hemorrhage types were obtained by multivariate logistic regression.

RESULTS: Previous stroke (P=0.023) and higher age (P<0.001) were independently associated with PHr, but not with PH. Atrial fibrillation, computed tomographic hyperdense cerebral artery sign, and elevated blood glucose were associated with PH, but not with PHr. Female sex had a stronger association with PHr than with PH. Functional independence at 3 months was more common in PHr than in PH (34% versus 24%; P<0.001), whereas 3-month mortality was lower (34% versus 39%; P<0.001).

CONCLUSIONS: Differences between risk factor profiles indicate an influence of previous vascular pathology in PHr and acute large-vessel occlusion in PH. Additional research is needed on the effect of pre-existing cerebrovascular disease on complications of recanalization therapy in acute ischemic stroke.

Background and Purpose: The risk of epilepsy after stroke has not been thoroughly explored in pediatric ischemic stroke. We examined the risk of epilepsy in children with ischemic stroke as well as in their first-degree relatives.

Methods: In Swedish National Registers, we identified 1220 children <18 years with pediatric ischemic stroke diagnosed 1969 to 2016, alive 7 days after stroke and with no prior epilepsy. We used 12 155 age- and sex-matched individuals as comparators. All first-degree relatives to index individuals and comparators were also identified. The risk of epilepsy was estimated in children with ischemic stroke and in their first-degree relatives using Cox proportional hazard regression model.

Results: Through this nationwide population-based study, 219 (18.0%) children with ischemic stroke and 91 (0.7%) comparators were diagnosed with epilepsy during follow-up corresponding to a 27.8-fold increased risk of future epilepsy (95% CI, 21.5-36.0). The risk of epilepsy was still elevated after 20 years (hazard ratio [HR], 7.9 [95% CI, 3.3-19.0]), although the highest HR was seen in the first 6 months (HR, 119.4 [95% CI, 48.0-297.4]). The overall incidence rate of epilepsy was 27.0 per 100 000 person-years (95% CI, 21.1-32.8) after ischemic stroke diagnosed <= day 28 after birth (perinatal) and 11.6 per 100 000 person-years (95% CI, 9.6-13.5) after ischemic stroke diagnosed >= day 29 after birth (childhood). Siblings and parents, but not offspring, to children with ischemic stroke were at increased risk of epilepsy (siblings: HR, 1.64 [95% CI, 1.08-2.48] and parents: HR, 1.41 [95% CI, 1.01-1.98]).

Conclusions: The risk of epilepsy after ischemic stroke in children is increased, especially after perinatal ischemic stroke. The risk of epilepsy was highest during the first 6 months but remained elevated even 20 years after stroke which should be taken into account in future planning for children affected by stroke.

Background and Purpose: Ischemic stroke is a common cause of death in adults, however, mortality after pediatric ischemic stroke is not well explored. We investigate long-term and cause-specific mortality in children with ischemic stroke and their first-degree relatives.

Methods: Through nationwide Swedish registers, we identified 1606 individuals <18 years old with ischemic stroke between 1969 and 2016 and their first-degree relatives (n=5714). Each individual with ischemic stroke was compared with 10 reference individuals (controls) matched for age, sex, and county of residence. Our main analysis examined 1327 children with ischemic stroke still alive 1 week after the event. First-degree relatives to children with ischemic stroke were compared with first-degree relatives to the reference individuals. Using a Cox proportional hazard regression model, the risk of overall and cause-specific mortality was computed in individuals with pediatric ischemic stroke and their first-degree relatives.

Results: The mortality rate in the first 6 months was 40.1 (95% CI, 24.7-55.6) per 1000 person-years compared with 1.1/1000 in controls (95% CI, 0.3-1.9). The overall mortality risk was hazard ratio (HR)=10.8 (95% CI, 8.1-14.3) and remained elevated beyond 20 years (HR=3.9 [95% CI, 2.1-7.1]). Children with ischemic stroke were at increased risk of death from neurological diseases (HR=29.9 [95% CI, 12.7-70.3]), cardiovascular diseases (HR=6.2 [95% CI, 1.8-22.2]), cancers (HR=6.5 [95% CI, 2.6-15.9]) and endocrine, nutritional and metabolic diseases (HR=49.2 [95% CI, 5.7-420.8]). First-degree relatives to children with ischemic stroke had an increased mortality risk (HR=1.21 [95% CI, 1.05-1.39]), with the highest risk among siblings (HR=1.52 [95% CI, 1.09-2.11]) and relatives to individuals with ischemic stroke >28 days of age (HR=1.23 [95% CI, 1.06-1.42]) compared with the relatives of the controls.

Conclusions: Long-term mortality increased after pediatric ischemic stroke, even 20 years later, with neurological diseases as the most frequent cause of death.

BACKGROUND AND PURPOSE: In this study, linked, anonymous data from The National Hospital Discharge Register and the Swedish Prescribed Drug Register were used for studying to what extent recommended drugs for secondary prevention after stroke and TIA were purchased by patients in the region of Stockholm, Sweden (2 million inhabitants).

METHODS: Data on purchased drugs for secondary stroke prevention during July 2005 to June 2006 by 17 902 patients >18 years discharged after stroke or TIA during the period 1997 to June 2005 were analyzed by age, gender, and year of discharge.

RESULTS: Antiplatelets and warfarin were purchased by 87% of all stroke and 83% of all TIA patients, antihypertensives by 74% and 70%, and lipid lowering drugs by 41% and 39%, respectively.

CONCLUSIONS: Time after discharge had only a minor influence on the proportion of patients purchasing the medicines.