Benjamin D. Bray

Estimating the financial cost of chronic kidney disease to the NHS in England.

Background Chronic kidney disease (CKD) is a major challenge for health care systems around the world, and the prevalence rates appear to be increasing. We estimate the costs of CKD in a universal health care system. Methods Economic modelling was used to estimate the annual cost of Stages 3–5 CKD to the National Health Service (NHS) in England, including CKD-related prescribing and care, renal replacement therapy (RRT), and excess strokes, myocardial infarctions (MIs) and Methicillin-Resistant Staphylococcus Aureus (MRSA) infections in people with CKD. Results The cost of CKD to the English NHS in 2009–10 is estimated at £1.44 to £1.45 billion, which is ∼1.3% of all NHS spending in that year. More than half this sum was spent on RRT, which was provided for 2% of the CKD population. The economic model estimates that ∼7000 excess strokes and 12 000 excess MIs occurred in the CKD population in 2009–10, relative to an age- and gender-matched population without CKD. The cost of excess strokes and MIs is estimated at £174–£178 million. Conclusions The financial impact of CKD is large, with particularly high costs relating to RRT and cardiovascular complications. It is hoped that these detailed cost estimates will be useful in analysing the cost-effectiveness of treatments for CKD.

Identification of risk factors associated with acute kidney injury in patients admitted to acute medical units

In 2009, the National Confidential Enquiry into Patient Outcome and Death (NCEPOD) report identified significant deficiencies in the management of acute kidney injury (AKI) in hospitals in the UK. Many errors arose from failure to recognise patients with AKI and those at risk of developing AKI. Currently, there is no universally accepted risk factor assessment for identifying such patients on admission to acute medical units (AMUs). A multicentre prospective observational study was performed in the AMUs of 10 hospitals in England and Scotland to define the risk factors associated with AKI and to assess quality of care. Data were collected on consecutive acute medical admissions over two separate 24-h periods. Acute kidney injury was present in 55/316 (17.7%) patients, with sepsis, hypovolaemia, chronic kidney disease (CKD) and diabetes mellitus identified as the major risk factors. Deficiencies in patient care were identified, reinforcing the continuing need to improve the management of AKI.

Associations between the organisation of stroke services, process of care, and mortality in England: prospective cohort study

Objective To estimate the relations between the organisation of stroke services, process measures of care quality, and 30 day mortality in patients admitted with acute ischaemic stroke. Design Prospective cohort study. Setting Hospitals (n=106) admitting patients with acute stroke in England and participating in the Stroke Improvement National Audit Programme and 2010 Sentinel Stroke Audit. Participants 36 197 adults admitted with acute ischaemic stroke to a participating hospital from 1 April 2010 to 30 November 2011. Main outcome measure Associations between process of care (the assessments, interventions, and treatments that patients receive) and 30 day all cause mortality, adjusting for patient level characteristics. Process of care was measured using six individual measures of stroke care and summarised into an overall quality score. Results Of 36 197 patients admitted with acute ischaemic stroke, 25 904 (71.6%) were eligible to receive all six care processes. Patients admitted to stroke services with high organisational scores were more likely to receive most (5 or 6) of the six care processes. Three of the individual processes were associated with reduced mortality, including two care bundles: review by a stroke consultant within 24 hours of admission (adjusted odds ratio 0.86, 95%confidence interval 0.78 to 0.96), nutrition screening and formal swallow assessment within 72 hours (0.83, 0.72 to 0.96), and antiplatelet therapy and adequate fluid and nutrition for first the 72 hours (0.55, 0.49 to 0.61). Receipt of five or six care processes was associated with lower mortality compared with receipt of 0-4 in both multilevel (0.74, 0.66 to 0.83) and instrumental variable analyses (0.62, 0.46 to 0.83). Conclusions Patients admitted to stroke services with higher levels of organisation are more likely to receive high quality care as measured by audited process measures of acute stroke care. Those patients receiving high quality care have a reduced risk of death in the 30 days after stroke, adjusting for patient characteristics and controlling for selection bias.

Weekly variation in health-care quality by day and time of admission: a nationwide, registry-based, prospective cohort study of acute stroke care.

BACKGROUND Studies in many health systems have shown evidence of poorer quality health care for patients admitted on weekends or overnight than for those admitted during the week (the so-called weekend effect). We postulated that variation in quality was dependent on not only day, but also time, of admission, and aimed to describe the pattern and magnitude of variation in the quality of acute stroke care across the entire week. METHODS We did this nationwide, registry-based, prospective cohort study using data from the Sentinel Stroke National Audit Programme. We included all adult patients (aged >16 years) admitted to hospital with acute stroke (ischaemic or primary intracerebral haemorrhage) in England and Wales between April 1, 2013, and March 31, 2014. Our outcome measure was 30 day post-admission survival. We estimated adjusted odds ratios for 13 indicators of acute stroke-care quality by fitting multilevel multivariable regression models across 42 4-h time periods per week. FINDINGS The study cohort comprised 74,307 patients with acute stroke admitted to 199 hospitals. Care quality varied across the entire week, not only between weekends and weekdays, with different quality measures showing different patterns and magnitudes of temporal variation. We identified four patterns of variation: a diurnal pattern (thrombolysis, brain scan within 12 h, brain scan within 1 h, dysphagia screening), a day of the week pattern (stroke physician assessment, nurse assessment, physiotherapy, occupational therapy, and assessment of communication and swallowing by a speech and language therapist), an off-hours pattern (door-to-needle time for thrombolysis), and a flow pattern whereby quality changed sequentially across days (stroke-unit admission within 4 h). The largest magnitude of variation was for door-to-needle time within 60 min (range in quality 35-66% [16/46-232/350]; coefficient of variation 18·2). There was no difference in 30 day survival between weekends and weekdays (adjusted odds ratio 1·03, 95% CI 0·95-1·13), but patients admitted overnight on weekdays had lower odds of survival (0·90, 0·82-0·99). INTERPRETATION The weekend effect is a simplification, and just one of several patterns of weekly variation occurring in the quality of stroke care. Weekly variation should be further investigated in other health-care settings, and quality improvement should focus on reducing temporal variation in quality and not only the weekend effect. FUNDING None.

Can a Novel Clinical Risk Score Improve Pneumonia Prediction in Acute Stroke Care? A UK Multicenter Cohort Study

Background Pneumonia frequently complicates stroke and has a major impact on outcome. We derived and internally validated a simple clinical risk score for predicting stroke‐associated pneumonia (SAP), and compared the performance with an existing score (A2DS2). Methods and Results We extracted data for patients with ischemic stroke or intracerebral hemorrhage from the Sentinel Stroke National Audit Programme multicenter UK registry. The data were randomly allocated into derivation (n=11 551) and validation (n=11 648) samples. A multivariable logistic regression model was fitted to the derivation data to predict SAP in the first 7 days of admission. The characteristics of the score were evaluated using receiver operating characteristics (discrimination) and by plotting predicted versus observed SAP frequency in deciles of risk (calibration). Prevalence of SAP was 6.7% overall. The final 22‐point score (ISAN: prestroke Independence [modified Rankin scale], Sex, Age, National Institutes of Health Stroke Scale) exhibited good discrimination in the ischemic stroke derivation (C‐statistic 0.79; 95% CI 0.77 to 0.81) and validation (C‐statistic 0.78; 95% CI 0.76 to 0.80) samples. It was well calibrated in ischemic stroke and was further classified into meaningful risk groups (low 0 to 5, medium 6 to 10, high 11 to 14, and very high ≥15) associated with SAP frequencies of 1.6%, 4.9%, 12.6%, and 26.4%, respectively, in the validation sample. Discrimination for both scores was similar, although they performed less well in the intracerebral hemorrhage patients with an apparent ceiling effect. Conclusions The ISAN score is a simple tool for predicting SAP in clinical practice. External validation is required in ischemic and hemorrhagic stroke cohorts.

Bigger, Faster? Associations Between Hospital Thrombolysis Volume and Speed of Thrombolysis Administration in Acute Ischemic Stroke

Background and Purpose— There is evidence that high-volume hospitals may produce better patient outcomes. We aimed to identify whether there were any associations between hospital thrombolysis volume and speed of thrombolysis (tissue-type plasminogen activator [tPA]) administration in patients with ischemic stroke. Methods— Data were drawn from 2 national clinical audits in England: the Stroke Improvement National Audit Program and the 2012 Sentinel Stroke Audit. Hospitals were categorized into 3 groups based on the annualized volume of thrombolysis: 0 to 24, 25 to 49, and ≥50 cases per annum. Arrival-brain scan, onset-tPA, and arrival-tPA times were compared across groups and stratified by onset-arrival time. Multilevel logistic models were used to estimate the odds of receiving tPA within 60 minutes of arrival. Results— Of the 42 024 patients with acute ischemic stroke admitted to 80 hospitals, 4347 received tPA (10.3%). Patients admitted to hospitals with an annual thrombolysis volume of ≥50 cases per annum had median arrival-tPA times that were 28 and 22 minutes shorter than patients admitted to hospitals with volumes of 0 to 24 and 25 to 49, respectively. Onset-tPA times were shorter by 24 to 32 minutes across strata of onset-arrival times. In multivariable analysis, patients admitted to hospitals with a volume of ≥50 cases per annum had 4.33 (2.21–8.50; P<0.0001) the odds of receiving tPA within 60 minutes of arrival. No differences in safety outcomes were observed, with similar 30-day mortality and complication rates across the groups. Conclusions— Hospitals with higher volumes of thrombolysis activity achieve statistically and clinically significant shorter delays in administering tPA to patients after arrival in hospital.

Patient outcomes up to 15 years after stroke: survival, disability, quality of life, cognition and mental health

Background The global epidemiological shift of disease burden towards long-term conditions means understanding long-term outcomes of cardiovascular disease is increasingly important. More people are surviving stroke to experience its long-term consequences, but outcomes in people living more >10 years after stroke have not been described in detail. Methods Data were collected for the population-based South London Stroke Register, with participants followed up annually until death. Outcomes were survival, disability, activity, cognitive impairment, quality of life, depression and anxiety. Findings Of 2625 people having first-ever stroke, 262 (21%) survived to 15 years. By 15 years, 61% (95% CI 55% to 67%) of the survivors were male, with a median age of stroke onset of 58 years (IQR 48–66). 87% of the 15-year survivors were living at home and 33.8% (26.2% to 42.4%) had mild disability, 14.3% (9.2% to 21.4%) moderate disability and 15.0% (9.9% to 22.3%) severe disability. The prevalence of disability increased with time but 1 in 10 of the 15-year survivors had lived with moderate-severe disability since their stroke. At 15 years, the prevalence of cognitive impairment was 30.0% (19.5% to 43.1%), depression 39.1% (30.9% to 47.9%) and anxiety 34.9% (27.0% to 43.8%), and survivors reported greater loss of physical than mental quality of life. Conclusions One in five people live at least 15 years after a stroke and poor functional, cognitive and psychological outcomes affect a substantial proportion of these long-term survivors. As the global population of individuals with cardiovascular long-term conditions grows, research and health services will need to increasingly focus on preventing and managing the long-term consequences of stroke.

Stroke thrombolysis in England: an age stratified analysis of practice and outcome

INTRODUCTION until very recently, only small numbers of older patients with stroke had been recruited into randomised controlled trials of thrombolysis with recombinant tissue plasminogen activator (rt-PA) and patients aged >80 are excluded in the European licence for this therapy. We aimed to estimate the use and outcome of stroke thrombolysis in England across age groups, including the oldest-old. METHODS data were collected as part of the Stroke Improvement National Audit Programme. All adults receiving thrombolysis for acute ischaemic stroke as part of routine care between April 2010 and November 2011 were included. Multilevel multivariable logistic regression was used to analyse the associations between age, process of care and 30-day mortality. RESULTS of 37,151 adults admitted with acute ischaemic stroke, 3,374 (9.1%) received rt-PA. Patients aged >80 accounted for 21% of the thrombolysis recipients and 4.8% of patients in this age group received rt-PA. Treatment times were similar across all age groups, but older thrombolysis recipients were more likely to have Total anterior circulation infarct strokes and less likely to be functionally independent prior to stroke. Similar rates of post-thrombolysis complications were observed between patients aged >80 and younger patients. Mortality was high among older patients whether they were treated with rt-PA or not. Among patients treated with rt-PA, those aged 81-90 and >90 had, respectively, 34 and 270% higher odds of 30-day mortality than patients aged 70-80. CONCLUSION treatment with rt-PA is now carried out frequently for older stroke patients in England. Their care is as timely as younger patients with no higher risk of major complication but mortality rates in older patients with stroke remain high.

The Effect of Out of Hours Presentation with Acute Stroke on Processes of Care and Outcomes: Analysis of Data from the Stroke Improvement National Audit Programme (SINAP)

Background There is inconsistent evidence that patients with stroke admitted to hospital out of regular working hours (such as weekends) experience worse outcomes. We aimed to identify if inequalities in the quality of care and mortality exist in contemporary stroke care in England. Methods SINAP is a prospective database of acute stroke patients, documenting details of processes of care over the first 72 hours. We compared quality of care indicators and mortality at 72 hours, 7 days and 30 days, for patients who arrived within normal hours (Monday–Friday 8am to 6pm) and for those who arrived out of hours, using multivariable logistic and Cox proportional hazard models. Quality of care was defined according to time from arrival at hospital to interventions (e.g., brain scan), and whether the patient received therapeutic interventions (such as thrombolysis). Results 45,726 stroke patients were admitted to 130 hospitals in England between 1 April 2010 and 31 January 2012. Patients admitted out of hours (n = 23779) had more features indicative of worse prognosis (haemorrhagic stroke, reduced consciousness, pre stroke dependency). Out of hours admission was significantly associated with longer delays in receiving a CT scan or being admitted to a stroke unit, and reduced odds of receiving thrombolysis. After adjusting for casemix, there was no consistent evidence of higher mortality for patients admitted out of hours, but patients admitted at the weekends had a higher risk of 30 day mortality (OR 1.14, 95% CI 1.06–1.21) Conclusion Inequalities in the provision of stroke care for people admitted out of regular hours persist in contemporary stroke in England. The association with mortality is small and largely attributable to higher illness severity in patients admitted out of hours.

How safe is renal replacement therapy? A national study of mortality and adverse events contributing to the death of renal replacement therapy recipients

BACKGROUND Patients receiving treatment with renal replacement therapy (RRT) have high mortality, and ensuring patient safety in this population is difficult. We aimed to estimate the incidence and nature of medical adverse events contributing to the death of patients being treated with RRT. METHODS This population registry-based retrospective case review study included all patients being treated with RRT for established renal failure in Scotland and who died between 1 January 2008 and 30 June 2011. Deaths were reviewed by consultant nephrologists using a structured questionnaire to identify factors contributing to death occurring in both the inpatient and outpatient setting. Reviewers were able to use any information source deemed relevant, including paper and electronic clinical records, mortality and morbidity meetings and procurator fiscal (Scottish coroner) investigations. Deaths occurring in 2008 and 2009 where avoidable factors were identified that may have or did lead to death of a patient were subject to further review and root cause analysis, in order to identify recurrent themes. RESULTS Of 1551 deaths in the study period, 1357 were reviewed (87.5%). Cumulative RRT exposure in the cohort was 2.78 million person-days. RRT complications were the primary cause of death in 28 (2.1%). Health-care-associated infection had contributed to 9.6% of all deaths. In 3.5% of deaths, factors were identified which may have or did contribute to death. These were both organizational and human error related and were largely due to five main causes: management of hyperkalaemia, prescribing, out of hours care, infection and haemodialysis vascular access. CONCLUSIONS Adverse events contributing to death in RRT recipients mainly relate to the everyday management of common medical problems and not the technical aspects of RRT. Efforts to avoid harm in this population should address these ubiquitous causes of harm.