Reporting ethical approval in health and social science articles: an audit of adherence to GDPR and national legislation.

BACKGROUND: Previous studies have indicated that failure to report ethical approval is common in health science articles. In social sciences, the occurrence is unknown. The Swedish Ethics Review Act requests that sensitive personal data, in accordance with the EU General Data Protection Regulation (GDPR), should undergo independent ethical review, irrespective of academic discipline. We have explored the adherence to this regulation. METHODS: Using the Web of Science databases, we reviewed 600 consecutive articles from three domains (health sciences with and without somatic focus and social sciences) based on identifiable personal data published in 2020. RESULTS: Information on ethical review was lacking in 12 of 200 health science articles with somatic focus (6%), 21 of 200 health science articles with non-somatic focus (11%), and in 54 of 200 social science articles (27%; p < 0.001 vs. both groups of health science articles). Failure to report on ethical approval was more common in (a) observational than in interventional studies (p < 0.01), (b) articles with only 1-2 authors (p < 0.001) and (c) health science articles from universities without a medical school (p < 0.001). There was no significant association between journal impact factor and failure to report ethical approval. CONCLUSIONS: We conclude that reporting of research ethics approval is reasonably good, but not strict, in health science articles. Failure to report ethical approval is about three times more frequent in social sciences compared to health sciences. Improved adherence seems needed particularly in observational studies, in articles with few authors and in social science research.

Net benefit of oral anticoagulants in patients with atrial fibrillation and active cancer: a nationwide cohort study.

AIMS: To estimate the net cerebrovascular benefit of prophylactic treatment with oral anticoagulants (OACs) in patients with atrial fibrillation (AF) and active cancer. METHODS AND RESULTS: We included all Swedish patients who had been diagnosed with AF in a hospital or in a hospital-associated outpatient unit between 1 July 2005 and 1 October 2017. Patients with active cancer (n = 22 596) and without cancer (n = 440 848) were propensity score matched for the likelihood of receiving OACs at baseline. At baseline, 38.3% of cancer patients with AF and high stroke risk according to CHA2DS2-VASc score received OACs. There was a net benefit of OACs, assessed by the composite outcome of ischaemic stroke, extracranial arterial thromboembolism, all major bleedings, and death, both among patients with active cancer [hazard ratio (HR): 0.81, confidence interval (CI): 0.78-0.85] and among patients without cancer (HR: 0.81, CI: 0.80-0.82). When limiting follow-up to 1 year to minimize the effects of possible treatment cross-over and additionally accounting for death as a competing risk in cancer patients, a net cerebrovascular benefit regarding ischaemic stroke or intracranial bleeding was observed for OACs [subhazard ratio (sHR): 0.67, CI: 0.55-0.83]. A net cerebrovascular benefit was also seen for non-vitamin K antagonist OACs over warfarin after competing risk analyses in cancer patients (sHR: 0.65, CI: 0.48-0.88). CONCLUSION: Patients with AF and active cancer benefit from OAC treatment.

Socioeconomic Status and the Risk of Stroke Recurrence: Persisting Gaps Observed in a Nationwide Swedish Study 2001 to 2012.

BACKGROUND AND PURPOSE: This nationwide observational study aimed to investigate how socioeconomic status is associated with risk of stroke recurrence and how possible associations change over time. METHODS: This study included 168 295 patients, previously independent in activities of daily living, with a first-ever stroke in the Swedish Stroke Register (Riksstroke) 2001 to 2012. Riksstroke was linked with Statistics Sweden as to add individual information on education and income. Subdistribution hazard regression was used to analyze time from 28 days after first stroke to stroke recurrence, accounting for the competing risk of other causes of death. RESULTS: Median time of follow-up was 3.0 years. During follow-up, 23 560 patients had a first recurrent stroke, and 53 867 died from other causes. The estimated cumulative incidence of stroke recurrence was 5.3% at 1 year, and 14.3% at 5 years. Corresponding incidence for other deaths were 10.3% and 30.2%. Higher education and income were associated with a reduced risk of stroke recurrence. After adjusting for confounding variables, university versus primary school education returned a hazard ratio of 0.902; 95% confidence interval, 0.864 to 0.942, and the highest versus the lowest income tertile a hazard ratio of 0.955; 95% confidence interval, 0.922 to 0.989. The risk of stroke recurrence decreased during the study period, but the inverse effect of socioeconomic status on risk of recurrence did not change significantly. CONCLUSIONS: Despite a declining risk of stroke recurrence over time, the differences in recurrence risk between different socioeconomic groups remained at a similar level in Sweden during 2001 to 2012.

Optimal Timing of Anticoagulant Treatment After Intracerebral Hemorrhage in Patients With Atrial Fibrillation.

BACKGROUND AND PURPOSE: This study aims to provide observational data on the relationship between the timing of antithrombotic treatment and the competing risks of severe thrombotic and hemorrhagic events in a cohort of Swedish patients with atrial fibrillation and intracerebral hemorrhage (ICH). METHODS: Patients with atrial fibrillation and a first-ever ICH were identified in the Swedish Stroke Register, Riksstroke, 2005 to 2012. Riksstroke was linked with other national registers to find information on treatment, comorbidity, and outcome. The optimal timing of treatment in patients with low and high thromboembolic risk was described through cumulative incidence functions separately for thrombotic and hemorrhagic events and for the combined end point vascular death or nonfatal stroke. RESULTS: The study included 2619 ICH survivors with atrial fibrillation with 5759 person-years of follow-up. Anticoagulant treatment was associated with a reduced risk of vascular death and nonfatal stroke in high-risk patients with no significantly increased risk of severe hemorrhage. The benefit seemed to be greatest when treatment was started 7 to 8 weeks after ICH. For high-risk women, the total risk of vascular death or stroke recurrence within 3 years was 17.0% when anticoagulant treatment was initiated 8 weeks after ICH and 28.6% without any antithrombotic treatment (95% confidence interval for difference, 1.4%-21.8%). For high-risk men, the corresponding risks were 14.3% versus 23.6% (95% confidence interval for difference, 0.4%-18.2%). CONCLUSIONS: This nationwide observational study suggests that anticoagulant treatment may be initiated 7 to 8 weeks after ICH in patients with atrial fibrillation to optimize the benefit from treatment and minimize risk.

Validation of Hospital Performance Measures of Acute Stroke Care Quality. Riksstroke, the Swedish Stroke Register.

BACKGROUND: Registers are increasingly used to monitor stroke care performance. Fair benchmarking requires sufficient data quality. We have validated acute care data in Riksstroke, the Swedish Stroke Register. METHODS: Completeness was assessed by comparisons with diagnoses at hospital discharge recorded in the compulsory National Patient Register and content validity by comparisons with (a) key variables identified by European stroke experts, and (b) items recorded in other European stroke care performance registers. Five test cases recorded by 67 hospitals were used to estimate inter-hospital reliability. RESULTS: All 72 Swedish hospitals admitting acute stroke patients participated in Riksstroke. The register was estimated to cover at least 90% of acute stroke patients. It includes 18 of 22 quality indicators identified by international stroke experts and 14 of 15 indicators used by at least 2 stroke performance registers in other European countries. Inter-hospital reliability was high (≥85%) in 77 of 81 Riksstroke items. CONCLUSIONS: A nationwide stroke care register can be maintained with sufficient data quality to permit between-hospital performance benchmarking. Our experiences may serve as a model for other stroke registers while evaluating data quality.

Diagnostic procedures, treatments, and outcomes in stroke patients admitted to different types of hospitals.

BACKGROUND AND PURPOSE: In many countries, including Sweden, initiatives have been taken to reduce between-hospital differences in the quality of stroke services. We have explored to what extent hospital type (university, specialized nonuniversity, or community hospital) influences hospital performance. METHODS: Riksstroke collects clinical data during hospital stay (national coverage 94%). Follow-up data at 3 months were collected using administrative registers and a questionnaire completed by surviving patients (response rate 88%). Structural data were collected from a questionnaire completed by hospital staff (response rate 100%). Multivariate analyses with adjustment for clustering were used to test differences between types of hospitals. RESULTS: The proportion of patients admitted directly to a stroke unit was highest in community hospitals and lowest in university hospitals. Magnetic resonance, carotid imaging, and thrombectomy were more frequently performed in university hospitals, and the door-to-needle time for thrombolysis was shorter. Secondary prevention with antihypertensive drugs was used less often, and outpatient follow-up was less frequent in university hospitals. Fewer patients in community hospitals were dissatisfied with their rehabilitation. After adjusting for possible confounders, poor outcome (dead or activities of daily living dependency 3 months after stroke) was not significantly different between the 3 types of hospital. CONCLUSIONS: In a setting with national stroke guidelines, stroke units in all hospitals, and measurement of hospital performance and benchmarking, outcome (after case-mix adjustment) is similar in university, specialized nonuniversity, and community hospitals. There seems to be fewer barriers to organizing well-functioning stroke services in community hospitals compared with university hospitals.

Socioeconomic Inequalities in the Prescription of Oral Anticoagulants in Stroke Patients With Atrial Fibrillation.

BACKGROUND AND PURPOSE: Oral anticoagulants (OACs) are effective against ischemic stroke in patients with atrial fibrillation. Our aim was to investigate differences in the prescribing of OACs after ischemic stroke in patients with atrial fibrillation based on age, sex, country of birth, and socioeconomic status. METHODS: Patients with first-ever ischemic stroke and atrial fibrillation without OAC treatment were included from the Swedish stroke register from 2009 to 2012. The outcome was OAC prescribed at discharge. Income, education, country of birth, and risk factors were obtained from official registers. Risk factors and health status were controlled for in multivariable logistic regression. RESULTS: Of 12 088 stroke patients, 36.3% were prescribed an OAC. Prescribing was less common with older age and, in patients born in other Nordic countries (odds ratio [OR], 0.82; 95% confidence interval [CI], 0.68-0.98) or countries outside of Europe (OR, 0.65; 95% CI, 0.42-0.99) compared with those born in Sweden. University education (OR, 1.20; 95% CI, 1.05-1.36) and highest income (OR, 1.19; 95% CI, 1.06-1.33) were associated with higher levels of OAC prescribing compared with those with primary school education or lowest income level. CONCLUSION: Differences by age, income, education, and country of birth were found in the prescribing of OACs after stroke. Differences were not explained by common risk factors. This indicates socioeconomic inequalities in the prescribing of preventive treatment after stroke.

Antithrombotic Treatment Following Intracerebral Hemorrhage in Patients With and Without Atrial Fibrillation.

BACKGROUND AND PURPOSE: Patients who survive intracerebral hemorrhage (ICH) often have compelling indications for anticoagulant and antiplatelet medication. This nationwide observational study aimed to determine the extent and predictors of antithrombotic treatment after ICH in Sweden. METHODS: Patients with a first-ever ICH in the Swedish Stroke Register (Riksstroke) 2005 to 2012 who survived hospital discharge were included. Riksstroke data were individually linked with other national registers to determine comorbid conditions and dispensed prescriptions of antithrombotic agents. RESULTS: Among the 2777 patients with atrial fibrillation (AF), the proportion with a dispensed prescription of antithrombotic agents was 8.5% (anticoagulants) and 36.6% (antiplatelet agents) within 6 months and 11.1% (anticoagulants) and 43.6% (antiplatelet agents) within 1 year. Among the 11 268 patients without AF, the corresponding figures were 1.6% (anticoagulants) and 13.8% (antiplatelet agents) within 6 months and 2.0% (anticoagulants) and 17.5% (antiplatelet agents) within 1 year. In patients with AF, predictors of anticoagulant treatment were less severe ICH, younger age, previous anticoagulation, valvular disease, and previous ischemic stroke. High CHA2DS2-VASc (congestive heart failure, hypertension, age, diabetes mellitus, stroke [doubled], vascular disease, age, and sex category [female]) scores did not correlate with anticoagulant treatment. There was a positive correlation between high CHA2DS2-VASc and HAS-BLED (hypertension, abnormal renal/liver function, stroke, bleeding history or predisposition, labile international normalized ratio, elderly, drugs/alcohol) scores (rs=0.590, P<0.001). CONCLUSIONS: In majority of patients who receive antithrombotic agents, treatment is initiated within 6 months of ICH. Still, many patients with compelling indications for antithrombotic treatment are not prescribed antithrombotic agents. Factors other than high risk of embolic stroke by CHA2DS2-VASc in ICH survivors with concurrent AF are used to guide the anticoagulant treatment decision in Swedish clinical practice.

Variations in acute hospital stroke care and factors influencing adherence to quality indicators in 6 European audits.

BACKGROUND AND PURPOSE: We compared compliance with standards of acute stroke care between 6 European audits and identified factors associated with delivery of appropriate care. METHODS: Data were derived from stroke audits in Germany, Poland, Scotland, Catalonia, Sweden, and England/Wales/Northern-Ireland participating within the European Implementation Score (EIS) collaboration. Associations between demographic and clinical characteristics with adherence to predefined quality indicators were investigated by hierarchical logistic regression analyses. RESULTS: In 2007/2008 data from 329 122 patients with stroke were documented. Substantial variations in adherence to quality indicators were found; older age was associated with a lower probability of receiving thrombolytic therapy, anticoagulant therapy, or stroke unit treatment and a higher probability of being tested for dysphagia. Women were less likely to receive anticoagulant or antiplatelet therapy or stroke unit treatment. No major weekend effect was found. CONCLUSIONS: Detected variations in performance of acute stroke services were found. Differences in adherence to quality indicators might indicate population subgroups with specific needs for improving care delivery.

Cross-National Key Performance Measures of the Quality of Acute Stroke Care in Western Europe.

BACKGROUND AND PURPOSE: There are no agreed measures of stroke care quality that enable the standardized comparison of stroke care between countries. We aimed to develop a set of measures of quality of acute stroke care involving stroke quality registers in Western Europe. METHODS: A multinational working group identified 6 regional or national stroke quality registers in Europe and reviewed their data sets, performance measures, and the method by which these had been developed. Measures used in the registers were presented for discussion to a consensus group of representatives from the quality registers identified, as well as other stroke experts, and the final set of common performance measures was agreed through majority consensus. RESULTS: Thirty final performance measures were agreed by the European consensus group, encompassing the domains of coordination of care (stroke unit-based care), diagnosis (brain imaging, vascular imaging, cardiac arrhythmia detection, and therapy assessment), preservation of neural tissue (thrombolytic therapy and door-to-needle time), prevention of complications (dysphagia screening), initiation of secondary prevention (antiplatelet, anticoagulation, lipid lowering, blood pressure lowering, carotid surgery, time from vascular imaging to carotid surgery, and smoking cessation), survival (90-day poststroke mortality), and functional outcomes (90-day modified Rankin Scale). CONCLUSIONS: On the basis of experience of quality registers in Europe, we have proposed a common set of performance measures that will facilitate the international comparison of acute stroke care quality.

High prevalence of atrial fibrillation among patients with ischemic stroke.

BACKGROUND AND PURPOSE: Atrial fibrillation (AF) is a common cause of devastating but potentially preventable stroke. Estimates of the prevalence of AF among patients with stroke vary considerably because of difficulties in detection of intermittent, silent AF. Better recognition of AF in this patient group may help to identify and offer protection to individuals at risk. Our aim was to determine the nationwide prevalence of AF among patients with ischemic stroke, as well as their use of oral anticoagulation. METHODS: Cross-sectional study of unselected patients in cross-linked nationwide Swedish health registers. All 94 083 patients with a diagnosis of ischemic stroke in the nationwide stroke register Riks-Stroke between 2005 and 2010 were studied. Information about previously diagnosed AF, and comorbidity, was obtained from the nationwide Patient Register and cross-referenced with the national Drug Register containing data on all dispensed pharmacological prescriptions in Sweden. RESULTS: Combination of data from Riks-Stroke and from the Patient Register showed that 31 428 (33.4%) patients with ischemic stroke had previously known, or newly diagnosed, AF. Of those, only 16.2% had received warfarin in a pharmacy within 6 months before stroke onset. After hospital discharge, only 35.0% of the survivors received warfarin within the first 3 months after discharge. The likelihood for underlying AF was strongly correlated to the CHA2DS2-VASC score, which is a point based scheme for assessment of stroke risk in AF but which also predicts likelihood of AF. In this scheme points are given for age, previous stroke or transient ischemic attack, hypertension, heart failure, diabetes, vascular disease and female sex. CONCLUSIONS: Access to nationwide register data shows that AF is more common among patients with ischemic stroke than those previously reported. Few patients with stroke and AF had anticoagulant treatment before the event, and few got it after the event. CHA2DS2-VASc could be a useful monitoring tool to intensify efforts to diagnose AF among patients with cryptogenic stroke.

Education level and inequalities in stroke reperfusion therapy: observations in the Swedish stroke register.

BACKGROUND AND PURPOSE: Previous studies have revealed inequalities in stroke treatment based on demographics, hospital type, and region. We used the Swedish Stroke Register (Riksstroke) to test whether patient education level is associated with reperfusion (either or both of thrombolysis and thrombectomy) treatment. METHODS: We included 85 885 patients with ischemic stroke aged 18 to 80 years registered in Riksstroke between 2003 and 2009. Education level was retrieved from Statistics Sweden, and thrombolysis, thrombectomy, patient, and hospital data were obtained from Riksstroke. We used multivariable logistic regression to analyze the association between reperfusion therapy and patient education. RESULTS: A total of 3649 (4.2%) of the patients received reperfusion therapy. University-educated patients were more likely to be treated (5.5%) than patients with secondary (4.6%) or primary education (3.6%; P<0.001). The inequality associated with education was still present after adjustment for patient characteristics; university education odds ratio, 1.14; 95% confidence interval, 1.03 to 1.26 and secondary education odds ratio, 1.08; 95% confidence interval, 1.00 to 1.17 compared with primary education. Higher hospital specialization level was also associated with higher reperfusion levels (P<0.001). In stratified multivariable analyses by hospital type, significant treatment differences by education level existed only among large nonuniversity hospitals (university education odds ratio, 1.20; 95% confidence interval, 1.04-1.40; secondary education odds ratio, 1.14; 95% confidence interval, 1.01-1.29). CONCLUSIONS: We demonstrated a social stratification in reperfusion, partly explained by patient characteristics and the local hospital specialization level. Further studies should address treatment delays, stroke knowledge, and means to improve reperfusion implementation in less specialized hospitals.

Trends in stroke treatment and outcome between 1995 and 2010: observations from Riks-Stroke, the Swedish stroke register.

BACKGROUND: Continuous changes in stroke treatment and care, as well as changes in stroke characteristics, may alter stroke outcome over time. The aim of this paper is to describe time trends for treatment and outcome data, and to discuss if any such changes could be attributed to quality changes in stroke care. METHODS: Data from Riks-Stroke, the Swedish stroke register, were analyzed for the time period of 1995 through 2010. The total number of patients included was 320,181. The following parameters were included: use of computed tomography (CT), stroke unit care, thrombolysis, medication before and after the stroke, length of stay in hospital, and discharge destination. Three months after stroke, data regarding walking, toileting and dressing ability, as well social situation, were gathered. Survival status after 7, 27 and 90 days was registered. RESULTS: In 1995, 53.9% of stroke patients were treated in stroke units. In 2010 this proportion had increased to 87.5%. Fewer patients were discharged to geriatric or rehabilitation departments in later years (23.6% in 2001 compared with 13.4% in 2010), but more were discharged directly home (44.2 vs. 52.4%) or home with home rehabilitation (0 vs. 10.7%). The need for home help service increased from 18.2% in 1995 to 22.1% in 2010. Regarding prevention, more patients were on warfarin, antihypertensives and statins both before and after the stroke. The functional outcome measures after 3 months did improve from 2001 to 2010. In 2001, 83.8% of patients were walking independently, while 85.6% were independent in 2010. For toileting, independence increased from 81.2 to 84.1%, and for dressing from 78.0 to 80.4%. Case fatality (CF) rates after 3 months increased from 18.7% (2001) to 20.0% (2010). This trend is driven by patients with severe strokes. CONCLUSIONS: Stroke outcomes may change over a relatively short time period. In some ways, the quality of care has improved. More stroke patients have CT, more patients are treated in stroke units and more have secondary prevention. Patients with milder strokes may have benefited more from these measures than patients with severe strokes. Increased CF rates for patients with severe stroke may be caused by shorter hospital stays, shorter in-hospital rehabilitation periods and lack of suitable care after discharge from hospital.

Costs for stroke in Sweden 2009 and developments since 1997.

OBJECTIVES: The aim of this study was to estimate direct and indirect excess costs attributable to stroke in Sweden in 2009 and to compare these with similar estimates from 1997. METHODS: Data on first-ever stoke admissions in the first half of 2009 from the Swedish national stroke register (RS) were used for cost calculations and compared with results from 1997 also using RS data. A societal perspective was taken including the acute and follow-up phase, rehabilitation, stroke re-admissions, drugs, home- and residential care services for activities of daily life (ADL) support, and indirect costs for premature death and productivity losses (2009 prices). Survival was extrapolated to estimate the lifetime present value cost of stroke. RESULTS: The societal lifetime present value cost for stroke in 2009 was €68,800 per patient (ADL support: 59 percent; productivity losses: 21 percent). Women had higher costs than men in all age groups as a result from greater need for ADL support. Patients treated at a stroke unit indicated low incremental cost per life-year gained compared with those who had not. The total lifetime cost increased between 1997 and 2009. Hospitalization costs per patient were stable, while long-term costs for home- and residential care services increased. CONCLUSIONS: Changes in patient characteristics, longer expected survival, and possibly in the Swedish stroke care, have led to higher annual and lifetime costs per patient in 2009 compared with 1997. A comprehensive national stroke care performance register like RS may be suitable for health economic assessments.

Implementing thrombolytic guidelines in stroke care: perceived facilitators and barriers.

We performed a qualitative study to identify facilitators of and barriers to the implementation of national guidelines on thrombolytic therapy for acute ischemic stroke. We interviewed physicians and nurses at nine Swedish hospitals using 16 explorative, semistructured interviews, and selected hospitals based on their implementation rate of new stroke care methods according to data from the Swedish Stroke Register, Riks-Stroke. Through content analysis, we identified facilitators and barriers to implementation, which we classified into three categories: (a) individuals, (b) social interactions and context, and (c) organizational and resource issues. Insights obtained from this study can be used to identify target areas for improving the implementation of thrombolytic therapy and other new methods in stroke care.

[Closure of emergency hospitals - a reemerging issue in Sweden]. / Nedläggningar av akutsjukhus tycks åter vara aktuella i Sverige.

As the finances of health care providers are increasingly strained, discussions about the closure of some of the emergency hospitals in Sweden have reemerged. I have reviewed the 39 closures that have occurred over the last half century. The closures have come in two distinct waves. The first wave, peaking in 1970-74, was driven by staffing problems with concerns about the quality of care. The second, more prolonged wave occurred in 1995-2004, caused by healthcare providers' strained economy. In 2024, the first closure of an emergency hospital since 2010 occurred and the future of several emergency hospitals is being investigated. A low population in the hospital catchment area has been a strong predictor of hospital closure, but the closure has seldom been followed by a marked population drop. Major arguments in the current debate on emergency hospital closures are listed. The process from a first external evaluation to final closure has followed a stereotypic, often dramatic pattern.

Differences in cardiovascular risk factors and socioeconomic status do not explain the increased risk of death after a first stroke in diabetic patients: results from the Swedish Stroke Register.

AIMS/HYPOTHESIS: This study compared survival rates and causes of death after stroke in diabetic and non-diabetic patients in Sweden. We hypothesised that differences in cardiovascular risk factors, acute stroke management or socioeconomic status (SES) could explain the higher risk of death after stroke in diabetic patients. METHODS: The study included 155,806 first-ever stroke patients from the Swedish Stroke Register between 2001 and 2009. Individual patient information on SES was retrieved from Statistics Sweden. Survival was followed until 2010 (532,140 person-years) with a median follow-up time of 35 months. Multiple Cox regression was used to analyse survival adjusting for differences in background characteristics, in-hospital treatment, SES and year of stroke. Causes of death were analysed using cause-specific proportional hazard models. RESULTS: The risk of death after stroke increased in diabetic patients (HR 1.28, 95% CI 1.25, 1.31), and this risk was greater in younger patients and in women. Differences in background characteristics, cardiovascular risk factors, in-hospital treatment and SES did not explain the increased risk of death after stroke (HR 1.35, 95% CI 1.32, 1.37) after adjustments. Diabetic patients had an increased probability of dying from cerebrovascular disease and even higher probabilities of dying from other circulatory causes and all other causes except cancer. CONCLUSIONS/INTERPRETATION: Differences in cardiovascular risk factors, acute stroke management and SES do not explain the lower survival after stroke in diabetic compared with non-diabetic patients. Diabetic patients are at higher risk of dying from cardiovascular causes and all other causes of death, other than cancer.

Statin therapy and outcome after ischemic stroke: systematic review and meta-analysis of observational studies and randomized trials.

BACKGROUND AND PURPOSE: Although experimental data suggest that statin therapy may improve neurological outcome after acute cerebral ischemia, the results from clinical studies are conflicting. We performed a systematic review and meta-analysis investigating the relationship between statin therapy and outcome after ischemic stroke. METHODS: The primary analysis investigated statin therapy at stroke onset (prestroke statin use) and good functional outcome (modified Rankin score 0 to 2) and death. Secondary analyses included the following: (1) acute poststroke statin therapy (≤ 72 hours after stroke), and (2) thrombolysis-treated patients. RESULTS: The primary analysis included 113 148 subjects (27 studies). Among observational studies, statin treatment at stroke onset was associated with good functional outcome at 90 days (pooled odds ratio [OR], 1.41; 95% confidence interval [CI], 1.29-1.56; P<0.001), but not 1 year (OR, 1.12; 95% CI, 0.9-1.4; P=0.31), and with reduced fatality at 90 days (pooled OR, 0.71; 95% CI, 0.62-0.82; P<0.001) and 1 year (OR, 0.80; 95% CI, 0.67-0.95; P=0.01). In the single randomized controlled trial reporting 90-day functional outcome, statin treatment was associated with good outcome (OR, 1.5; 95% CI, 1.0-2.24; P=0.05). No reduction in fatality was observed on meta-analysis of data from 3 randomized controlled trials (P=0.9). In studies restricted to of thrombolysis-treated patients, an association between statins and increased fatality at 90 days was observed (pooled OR, 1.25; 95% CI, 1.02-1.52; P=0.03, 3 studies, 4339 patients). However, this association was no longer present after adjusting for age and stroke severity in the largest study (adjusted OR, 1.14; 95% CI, 0.90-1.44; 4012 patients). CONCLUSIONS: In the largest meta-analysis to date, statin therapy at stroke onset was associated with improved outcome, a finding not observed in studies restricted to thrombolysis-treated patients. Randomized trials of statin therapy in acute ischemic stroke are needed.

Refinement of Swedish administrative registers to monitor stroke events on the national level.

BACKGROUND: Routinely collected databases are kept for administrative purposes. We have refined the analyses of the Swedish National Patient Register and the Cause of Death Register and explored their validity to monitor stroke at the population level. METHODS: First-ever strokes (incident cases) and all stroke events were measured by combining the two administrative registers and adding refinements. The administrative registers were validated against the Northern Sweden MONICA, a well-validated population-based epidemiological stroke register. Positive predictive values (PPVs) and sensitivity were calculated. RESULTS: After refinements (restriction to first-ever strokes and additional minor delineations), the PPV of the two administrative registers combined was 94% and sensitivity 92% when compared with all MONICA stroke categories together. For stroke attacks (first and recurrent events together), the PPV in the administrative registers was 85% and sensitivity 91%. The PPV was higher in women than in men, whereas the sensitivity was similar. The PPV was lower but sensitivity higher in people below compared with those above 75 years of age. Both PPV and sensitivity were lower among fatal cases than among cases that survived 28 days. CONCLUSIONS: After refinement, Swedish national administrative registers may, with some caveats, be used as a low-resource-consuming alternative to crudely monitor stroke incidence rates at the national level. If further accuracy is strived for, high-quality conventional epidemiological registers are required.