Significant variation in mortality and functional outcome after acute ischaemic stroke between Western countries: data from the tinzaparin in acute ischaemic stroke trial (TAIST)

Comparison of Hospital Performance in Acute Ischemic Stroke Based on Mortality and Functional Outcome in South Korea

BACKGROUND

Recent evidence suggests a correlation between modified Rankin Scale-based measures, an outcome measure commonly used in acute stroke trials, and mortality-based measures used by health agencies in the evaluation of hospital performance. We aimed to examine whether the 2 types of measures are interchangeable in relation to evaluation of hospital performance in acute ischemic stroke.

METHODS

Five outcome measures, unfavorable functional outcome (3-month modified Rankin Scale score ≥2), death or dependency (3-month modified Rankin Scale score ≥3), 1-month mortality, 3-month mortality, and 1-year mortality, were collected for 8292 individuals who were hospitalized for acute ischemic stroke between January 2014 and May 2015 in 14 hospitals participating in the Clinical Research Collaboration for Stroke in Korea - National Institute of Health registry. Hierarchical regression models were used to calculate per-hospital risk-adjusted outcome rates for each measure. Hospitals were ranked and grouped based on the risk-adjusted outcome rates, and the correlations between the modified Rankin Scale-based and mortality-based ranking and their intermeasure reliability in categorizing hospital performance were analyzed.

RESULTS

The comparison between the ranking based on the unfavorable functional outcome and that based on 1-year mortality resulted in a Spearman correlation coefficient of -0.29 and Kendall rank coefficient of -0.23, and the comparison of grouping based on these 2 types of ranks resulted in a weighted kappa of 0.123 for the grouping in the top 33%/middle 33%/bottom 33% and 0.25 for the grouping in the top 20%/middle 60%/bottom 20%, respectively. No significant correlation or similarity in grouping capacities were found between the rankings based on the functional outcome measures and those based on the mortality measures.

CONCLUSIONS

This study shows that regardless of clinical correlation at an individual patient level, functional outcome-based measures and mortality-based measures are not interchangeable in the evaluation of hospital performance in acute ischemic stroke.

Between-center and between-country differences in outcome after aneurysmal subarachnoid hemorrhage in the Subarachnoid Hemorrhage International Trialists (SAHIT) repository

OBJECTIVE

Differences in clinical outcomes between centers and countries may reflect variation in patient characteristics, diagnostic and therapeutic policies, or quality of care. The purpose of this study was to investigate the presence and magnitude of between-center and between-country differences in outcome after aneurysmal subarachnoid hemorrhage (aSAH).

METHODS

The authors analyzed data from 5972 aSAH patients enrolled in randomized clinical trials of 3 different treatments from the Subarachnoid Hemorrhage International Trialists (SAHIT) repository, including data from 179 centers and 20 countries. They used random effects logistic regression adjusted for patient characteristics and timing of aneurysm treatment to estimate between-center and between-country differences in unfavorable outcome, defined as a Glasgow Outcome Scale score of 1-3 (severe disability, vegetative state, or death) or modified Rankin Scale score of 4-6 (moderately severe disability, severe disability, or death) at 3 months. Between-center and between-country differences were quantified with the median odds ratio (MOR), which can be interpreted as the ratio of odds of unfavorable outcome between a typical high-risk and a typical low-risk center or country.

RESULTS

The proportion of patients with unfavorable outcome was 27% (n = 1599). The authors found substantial between-center differences (MOR 1.26, 95% CI 1.16-1.52), which could not be explained by patient characteristics and timing of aneurysm treatment (adjusted MOR 1.21, 95% CI 1.11-1.44). They observed no between-country differences (adjusted MOR 1.13, 95% CI 1.00-1.40).

CONCLUSIONS

Clinical outcomes after aSAH differ between centers. These differences could not be explained by patient characteristics or timing of aneurysm treatment. Further research is needed to confirm the presence of differences in outcome after aSAH between hospitals in more recent data and to investigate potential causes.

Bachmann M, Loke YK, D. Musgrave S, Price GM, Hale R, Metcalf AK, Turner DA, Day DJ, A. Warburton E, Potter JF. Important factors in predicting mortality outcome from stroke: findings from the Anglia Stroke Clinical Network Evaluation Study

Background

although variation in stroke service provision and outcomes have been previously investigated, it is less well known what service characteristics are associated with reduced short- and medium-term mortality.

Methods

data from a prospective multicentre study (2009–12) in eight acute regional NHS trusts with a catchment population of about 2.6 million were used to examine the prognostic value of patient-related factors and service characteristics on stroke mortality outcome at 7, 30 and 365 days post stroke, and time to death within 1 year.

Results

a total of 2,388 acute stroke patients (mean (standard deviation) 76.9 (12.7) years; 47.3% men, 87% ischaemic stroke) were included in the study. Among patients characteristics examined increasing age, haemorrhagic stroke, total anterior circulation stroke type, higher prestroke frailty, history of hypertension and ischaemic heart disease and admission hyperglycaemia predicted 1-year mortality. Additional inclusion of stroke service characteristics controlling for patient and service level characteristics showed varying prognostic impact of service characteristics on stroke mortality over the disease course during first year after stroke at different time points. The most consistent finding was the benefit of higher nursing levels; an increase in one trained nurses per 10 beds was associated with reductions in 30-day mortality of 11–28% (P < 0.0001) and in 1-year mortality of 8–12% (P < 0.001).

Conclusions

there appears to be consistent and robust evidence of direct clinical benefit on mortality up to 1 year after acute stroke of higher numbers of trained nursing staff over and above that of other recognised mortality risk factors.

Citicoline for Acute Ischemic Stroke: A Systematic Review and Formal Meta-analysis of Randomized, Double-Blind, and Placebo-Controlled Trials

BACKGROUND

Citicoline is a drug approved for the treatment of acute ischemic stroke. Although evidence of its efficacy has been reported, recently published results of a large placebo-controlled clinical trial did not show differences. This study aims to assess whether starting citicoline treatment within 14 days after stroke onset improves the outcome in patients with acute ischemic stroke, as compared with placebo.

METHODS

A systematic search was performed to identify all published, unconfounded, randomized, double-blind, and placebo-controlled clinical trials of citicoline in acute ischemic stroke.

RESULTS

Ten randomized clinical trials met our inclusion criteria. The administration of citicoline was associated with a significant higher rate of independence, independently of the method of evaluation used (odds ratio [OR] 1.56, 95% confidence interval [CI] = 1.12-2.16 under random effects; OR 1.20, 95% CI = 1.06-1.36 under fixed effects). After studying the cumulative meta-analysis, and with the results obtained with the subgroup of patients who were not treated with recombinant tissue plasminogen activator (rtPA) (OR 1.63, 95% CI = 1.18-2.24 under random effects; OR 1.42, 95% CI = 1.22-1.66 under fixed effects), our hypothesis of dilution of the effect of citicoline was confirmed. When we analyzed the effect of citicoline in patients who were not treated with rtPA and were receiving the highest dose of citicoline started in the first 24 hours after onset, based on more recent trials, there was no heterogeneity, and the size of the effect has an OR of 1.27 (95% CI = 1.05-1.53).

CONCLUSIONS

This systematic review supports some benefits of citicoline in the treatment of acute ischemic stroke. But, on top of the best treatment available (rtPA), citicoline offers a limited benefit.

Trends in Outcome and Hospitalization Cost among Adult Patients with Acute Ischemic Stroke in the United States

INTRODUCTION

New treatments for acute ischemic stroke (AIS) have been introduced and are expected to improve patients' overall outcomes. We assessed the impact of new therapeutic strategies on outcome and cost of hospitalization among adult patients with AIS in the United States.

METHODS

Patients with AIS admitted in the United States in 1993-1994 and 2006-2007 were listed using the Nationwide Inpatient Survey database. We determined the rates of occurrence, hospitalization outcomes, and mean hospital charges for all patients. We further analyzed these variables in the ventilated and nonventilated patients.

RESULTS

We identified 386,043 patients with AIS admitted in the United States in 1993-1994 and 749,766 patients in 2006-2007. The length of hospitalization was significantly higher in 1993-1994 compared with 2006-2007: 6.9 ± 4.2 days versus 4.66 ± 3 days, respectively. In-hospital mortality rate was 8.9% in 1993-1994 and 5.6% in 2006-2007 (P < 0.0001). There was a significant increase in mean hospital charges in 2006-2007 compared with 1993-1994 ($21,916 ± $14,117 versus $9,646 ± $5,727). The length of hospitalization was significantly shorter in 2006-2007 in nonventilated patients. There was a significant increase in mean hospital charges in 2006-2007 compared with 1993-1994 in both ventilated ($81,528 ± $64,526 versus $25,143 ± $17,172, P<0.0001) and nonventilated patients ($21,085 ± $13,042 versus $10,000 ± $6,300, P<0.0001). The mortality rate was significantly lower in 2006-2007 in both subgroups: 46.5% versus 59.8% in ventilated patients and 4.2% versus 8.2% in nonventilated patients (P < 0.0001).

CONCLUSION

Our study suggests that new therapeutic strategies have improved outcomes and increased cost of hospitalization among adult patients with AIS in the United States over a period of 13 years. The hospitalization cost was significantly higher in the ventilated and nonventilated patients in 2006-2007, which may reflect the impact of new therapeutic strategies, the availability of more intensive care units and stroke centers, and the lower mortality rate in this time period.

Very low quality of life after acute stroke: data from the Efficacy of Nitric Oxide in Stroke trial

BACKGROUND AND PURPOSE

Health-related quality of life, a key outcome after stroke, plays a role in the analysis of treatment cost-effectiveness. Some measures of health-related quality of life allow for a quality of life worse than death; the characteristics of such patients have not been well described.

METHODS

Data from the Efficacy of Nitric Oxide in Stroke (ENOS) trial were used to explore health-related quality of life after stroke. The EuroQol questionnaire (EQ-5D) was performed at day 90, and a health utility score (HUS) was calculated. HUS was defined as follows: poor-good HUS>0, death HUS=0, and very poor HUS<0. The characteristics and outcomes of patients with HUS<0 were then explored.

RESULTS

Of the 2569 patients, 303 (11.8%) died, and of the 2238 with quality of life data available, of whom 724 (32.3%) were completed by a proxy, 1959 (87.5%) had an HUS>0 and 279 (12.5%) had an HUS<0. Patients with HUS<0 were more likely to be older, women, have severe stroke, have proxy responders, and be institutionalized. Dominant hemisphere strokes were more likely to have proxy responders but not HUS<0. HUS was strongly correlated with dependency (modified Rankin Scale, r=-0.78) and disability (Barthel index, r=0.84) and moderately correlated with mood (Zung depression score, r=-0.59) and baseline severity (r=0.51). All but 1 patient with modified Rankin Scale of 5 had an HUS<0.

CONCLUSIONS

Very low health-related quality of life is relatively common after stroke, particularly in patients with mobility problems or who are dependent on help for usual activities, and is related to poor functional outcome measures.

CLINICAL TRIAL REGISTRATION URL

http://www.controlled-trials.com/. Unique identifier: ISRCTN99414122.

Comparison of 90-day case-fatality after ischemic stroke between two different stroke outcome registries using propensity score matching analysis

BACKGROUND

It has not been clarified whether the disparity in ischemic stroke outcome between populations is caused by ethnic and geographic differences or by variations in case mix. Propensity score matching (PSM) analysis can overcome some analytical problems but is rarely used in stroke outcome research. This study was to compare the ischemic stroke case-fatality between two PSM cohorts of Sweden and Korea.

METHODS

Prognostic variables related to baseline characteristics and stroke care were included in our PSM model. Then, we selected 7675 Swedish and 1220 Korean patients with ischemic stroke from each stroke registers and performed one-to-one matching based on propensity scores of each patient.

RESULTS

After PSM, all measured variables were well balanced in 1163 matched subjects, and the 90-day case-fatality was identical 6.2% (HR 0.997, 95%CI 0.905-1.099) in Sweden and Korea.

CONCLUSIONS

No difference is found in the 90-day case-fatality in propensity score-matched Swedish and Korean patients with ischemic stroke.

Evaluation of stroke services in Anglia Stroke Clinical Network to examine the variation in acute services and stroke outcomes

Background

Stroke is the third leading cause of death in developed countries and the leading cause of long-term disability worldwide. A series of national stroke audits in the UK highlighted the differences in stroke care between hospitals. The study aims to describe variation in outcomes following stroke and to identify the characteristics of services that are associated with better outcomes, after accounting for case mix differences and individual prognostic factors.

Methods/Design

We will conduct a cohort study in eight acute NHS trusts within East of England, with at least one year of follow-up after stroke. The study population will be a systematically selected representative sample of patients admitted with stroke during the study period, recruited within each hospital. We will collect individual patient data on prognostic characteristics, health care received, outcomes and costs of care and we will also record relevant characteristics of each provider organisation. The determinants of one year outcome including patient reported outcome will be assessed statistically with proportional hazards regression models. Self (or proxy) completed EuroQol (EQ-5D) questionnaires will measure quality of life at baseline and follow-up for cost utility analyses.

Discussion

This study will provide observational data about health service factors associated with variations in patient outcomes and health care costs following hospital admission for acute stroke. This will form the basis for future RCTs by identifying promising health service interventions, assessing the feasibility of recruiting and following up trial patients, and provide evidence about frequency and variances in outcomes, and intra-cluster correlation of outcomes, for sample size calculations. The results will inform clinicians, public, service providers, commissioners and policy makers to drive further improvement in health services which will bring direct benefit to the patients.

Stroke presentation and hospital management: comparison of neighboring healthcare systems with differing health policies

BACKGROUND AND PURPOSE

Acute stroke care is shaped by healthcare policies. Differing policies in similar populations allow for assessment of policy impact on health and healthcare outcomes. The purpose of this study was to compare stroke presentation and hospital care in two adjacent healthcare systems with differing healthcare policies.

METHODS

Interviews and chart review of consecutive acute stroke admissions in Northern Ireland (n=103) and the Republic of Ireland (n=100).

RESULTS

Marked regional contrasts were evident for key aspects of hospital care. Northern Ireland performed significantly better on 15 of 16 quality of care (Sentinel Audit) items. Delivery on standards was significantly better in Northern Ireland for early assessment (Northern Ireland 72%; Republic of Ireland 54%, P<0.01), multidisciplinary review (Northern Ireland 69%; Republic of Ireland 31%, P<0.001), medications review (Northern Ireland 54%; Republic of Ireland 19%, P<0.001), and for discharge-rehabilitation planning (Northern Ireland 83%; Republic of Ireland 8%, P<0.001). Preadmission prescription of advised cardiovascular medications was similar between regions for antihypertensives and anticoagulants but significantly higher in Northern Ireland for antiplatelets (Northern Ireland 65%; Republic of Ireland 38%, P=0.001) and lipid-regulating medication (Northern Ireland 44%; Republic of Ireland 26%; P=0.006). Prescribing levels increased in both regions and all medication categories by discharge but with significantly lower levels in Northern Ireland for antihypertensives (Northern Ireland 60%; Republic of Ireland 75%, P=0.025). Northern Ireland patients were more functionally dependent (mean Barthel Index 10.5 versus 12.7 [Republic of Ireland], P=0.013) and less aphasic (mean Frenchay Aphasia Screening Test 17.8 versus 16.8 [Republic of Ireland], P=0.022).

CONCLUSIONS

In similar neighboring acute stroke populations, differing healthcare policies were associated with significant differences in processes of patient care. Policy reform is an important tool in ensuring optimal stroke care delivery.

Stroke Outcome in Clinical Trial Patients Deriving From Different Countries

Background and Purpose— Stroke incidence and outcome vary widely within and across geographical locations. We examined whether differences in index stroke severity, stroke risk factors, mortality, and stroke outcome across geographical locations remain after adjusting for case mix.

Methods— We analyzed 3284 patients from the Virtual International Stroke Trials Archive (VISTA). We used logistic regression to examine the incidence of mild index stroke, functional, and neurological outcomes after accounting for age, medical history, year of trial recruitment, and initial stroke severity in the functional and neurological outcome analyses. We examined mortality between geographical regions using a Cox proportional hazards model, accounting for age, initial stroke severity, medical history, and year of trial recruitment.

Results— Patients enrolled in the USA and Canada had the most severe index strokes. Those recruited in Austria and Switzerland had the best functional and neurological outcomes at 90 days ( P <0.05), whereas those enrolled in Germany had the worst functional outcome at 90 days ( P =0.013). Patients enrolled in Austria, Switzerland, Belgium, Netherlands, Finland, Germany, Greece, Israel, Spain, and Portugal had a significantly better survival rate when compared with those enrolled in USA and Canada. Patients enrolled in trials after 1998 had more severe index strokes, with no significant difference in outcome compared with those enrolled before 1998.

Conclusion— We identified regional variations in index stroke severity, outcome, and mortality for patients enrolled in ischemic stroke clinical trials over the past 13 years that were not fully explained by case mix. Index stroke severity was greater in patients enrolled after 1998, with no significant improvement in outcomes compared to those enrolled before 1998.

Clinical pharmacological issues in the development of acute stroke therapies

The demonstration of the ischaemic penumbra in animal models and the effectiveness of reperfusion therapy in humans led to considerable optimism for neuroprotection in acute stroke. Initial experience with failure of phase II and III trials led to the STAIR recommendations for pre-clinical and clinical studies. Review of pre-clinical studies suggests that selection of agents for clinical development may not have been optimal. The neuroprotective agent NXY-059 fulfilled pre-clinical and many clinical STAIR criteria but a second large phase III study failed to demonstrate any benefit. Many of the STAIR criteria have not been fulfilled in the development of recent neuroprotective agents. Other issues not addressed include the use of animal models more reflective of older stroke patients with physiological derangement, demonstration of drug distribution to the proposed site of action in humans, selection of patients with salvageable tissue, achieving very early treatment, refinement of measurement of neurological impairment and disability, and physiological optimization in proof of concept human studies. Increasing the number and quality of clinical centres undertaking acute stroke research, use of surrogate imaging markers and adaptive dose designs in phase II trials could improve the likelihood of identifying an effective neuroprotective. Neuroprotection in acute stroke remains a significant challenge but has not been clearly shown to be ineffective. Given the profound burden of stroke and limited applicability of reperfusion to currently at best 10% patients, further proof of concept studies of neuroprotection remain indicated with careful review of pre-clinical data and more rigorous phase II trial design.

The hospital costs of care for stroke in nine European countries

Stroke is a major cause of mortality and morbidity, but the reasons for differences in costs of care within and between countries are not well understood. The HealthBASKET project used a vignette methodology to compare the mean costs and prices of hospital care across providers in nine European Union countries. Data on resource use, unit costs and prices of care for female stroke patients without co-morbidity were collected from a sample of 50 hospitals. Mean costs for each provider were analysed using multiple regression. Sensitivity analysis explored the effects on cost of using official exchange rates, purchasing power parity (PPP) and proportion of national income per capita. The mean cost of a hospital episode per patient for stroke at PPP was 3813 euros (standard error 227) with an additional day in hospital typically associated with 6.9% (95% CI: 4-9%) higher costs and thrombolysis associated with 41% higher costs (10-73%). After adjusting for explanatory factors, about 76% of the variation in cost could be attributed to between-country differences, and the extent of this variation was sensitive to the method of currency conversion. There was considerable variation in the care pathways within and between countries, including differences in the availability of stroke units and access to rehabilitative services, but only the length of stay and use of thrombolytic therapy were significantly associated with higher cost. The vignette methodology appears feasible, but further research needs to consider access to healthcare over a longer follow up and to include both costs and outcomes.

Improving the outcome of stroke

UK needs to reorganise services to follow the example of other countries

National variations in mortality and functional outcome: should we be worried?

International registries should be established to monitor process and outcome of care after stroke