Role of hospital strain in determining outcomes for people hospitalised with COVID-19 in England.

BACKGROUND: In England, reported COVID-19 mortality rates increased during winter 2020/21 relative to earlier summer and autumn months. This study aimed to examine the association between COVID-19-related hospital bed-strain during this time and patient outcomes. METHODS: This was a retrospective observational study using Hospital Episode Statistics data for England. All unique patients aged ≥18 years in England with a diagnosis of COVID-19 who had a completed (discharged alive or died in hospital) hospital stay with an admission date between 1 July 2020 and 28 February 2021 were included. Bed-strain was calculated as the number of beds occupied by patients with COVID-19 divided by the maximum COVID-19 bed occupancy during the study period. Bed-strain was categorised into quartiles for modelling. In-hospital mortality was the primary outcome of interest and length of stay a secondary outcome. RESULTS: There were 253 768 unique hospitalised patients with a diagnosis of COVID-19 during a hospital stay. Patient admissions peaked in January 2021 (n=89 047), although the crude mortality rate peaked slightly earlier in December 2020 (26.4%). After adjustment for covariates, the mortality rate in the lowest and highest quartile of bed-strain was 23.6% and 25.3%, respectively (OR 1.13, 95% CI 1.09 to 1.17). For the lowest and the highest quartile of bed-strain, adjusted mean length of stay was 13.2 days and 11.6 days, respectively in survivors and was 16.5 days and 12.6 days, respectively in patients who died in hospital. CONCLUSIONS: High levels of bed-strain were associated with higher in-hospital mortality rates, although the effect was relatively modest and may not fully explain increased mortality rates during winter 2020/21 compared with earlier months. Shorter hospital stay during periods of greater strain may partly reflect changes in patient management over time.

Data quality and autism: Issues and potential impacts.

INTRODUCTION: Large healthcare datasets can provide insight that has the potential to improve outcomes for patients. However, it is important to understand the strengths and limitations of such datasets so that the insights they provide are accurate and useful. The aim of this study was to identify data inconsistencies within the Hospital Episodes Statistics (HES) dataset for autistic patients and assess potential biases introduced through these inconsistencies and their impact on patient outcomes. The study can only identify inconsistencies in recording of autism diagnosis and not whether the inclusion or exclusion of the autism diagnosis is the error. METHODS: Data were extracted from the HES database for the period 1st April 2013 to 31st March 2021 for patients with a diagnosis of autism. First spells in hospital during the study period were identified for each patient and these were linked to any subsequent spell in hospital for the same patient. Data inconsistencies were recorded where autism was not recorded as a diagnosis in a subsequent spell. Features associated with data inconsistencies were identified using a random forest classifiers and regression modelling. RESULTS: Data were available for 172,324 unique patients who had been recorded as having an autism diagnosis on first admission. In total, 43.7 % of subsequent spells were found to have inconsistencies. The features most strongly associated with inconsistencies included greater age, greater deprivation, longer time since the first spell, change in provider, shorter length of stay, being female and a change in the main specialty description. The random forest algorithm had an area under the receiver operating characteristic curve of 0.864 (95 % CI [0.862 - 0.866]) in predicting a data inconsistency. For patients who died in hospital, inconsistencies in their final spell were significantly associated with being 80 years and over, being female, greater deprivation and use of a palliative care code in the death spell. CONCLUSIONS: Data inconsistencies in the HES database were relatively common in autistic patients and were associated a number of patient and hospital admission characteristics. Such inconsistencies have the potential to distort our understanding of service use in key demographic groups.

Safety of day-case endoscopic sinus surgery in England: An observational study using an administrative dataset.

INTRODUCTION: As elective surgical services recover from the COVID-19 pandemic a movement towards day-case surgery may reduce waiting lists. However, evidence is needed to show that day-case surgery is safe for endoscopic sinus surgery (ESS). The aim of this study was to investigate the safety of day-case ESS in England. DESIGN: Secondary analysis of administrative data. METHODS: We extracted data from the Hospital Episodes Statistics database for the 5 years from 1 April 2014 to 31 March 2019. Patients undergoing elective ESS procedures aged ≥17 years were included. Exclusion criteria included malignant neoplasm, complex systemic disease and trans-sphenoidal pituitary surgery. The primary outcome was readmission within 30 days post-discharge. Multilevel, multivariable logistic regression modelling was used to compare outcomes for those operated on as day-cases and those with an overnight stay after adjusting for demographic, frailty, comorbidity and procedural covariates. RESULTS: Data were available for 49 223 patients operated on across 129 NHS hospital trusts. In trusts operating on more than 50 patients in the study period, rates of day-case surgery varied from 20.6% to 100%. Nationally, rates of day-case surgery increased from 64.0% in the financial year 2014/2015 to 78.7% in 2018/2019. Day-case patients had lower rates of 30-day emergency readmission (odds ratio 0.71, 95% confidence interval 0.62 to 0.81). Outcomes for patients operated on in trusts with ≥80% day-case rates compared with patients operated on in trusts with <50% rates of day-case surgery were similar. CONCLUSIONS: Our data support the view that ESS can safely be performed as day-case surgery in most cases, although it will not be suitable for all patients. There appears to be scope to increase rates of day-case ESS in some hospital trusts in England.

Frailty, Comorbidity, and Associations With In-Hospital Mortality in Older COVID-19 Patients: Exploratory Study of Administrative Data.

BACKGROUND: Older adults have worse outcomes following hospitalization with COVID-19, but within this group there is substantial variation. Although frailty and comorbidity are key determinants of mortality, it is less clear which specific manifestations of frailty and comorbidity are associated with the worst outcomes. OBJECTIVE: We aimed to identify the key comorbidities and domains of frailty that were associated with in-hospital mortality in older patients with COVID-19 using models developed for machine learning algorithms. METHODS: This was a retrospective study that used the Hospital Episode Statistics administrative data set from March 1, 2020, to February 28, 2021, for hospitalized patients in England aged 65 years or older. The data set was split into separate training (70%), test (15%), and validation (15%) data sets during model development. Global frailty was assessed using the Hospital Frailty Risk Score (HFRS) and specific domains of frailty were identified using the Global Frailty Scale (GFS). Comorbidity was assessed using the Charlson Comorbidity Index (CCI). Additional features employed in the random forest algorithms included age, sex, deprivation, ethnicity, discharge month and year, geographical region, hospital trust, disease severity, and International Statistical Classification of Disease, 10th Edition codes recorded during the admission. Features were selected, preprocessed, and input into a series of random forest classification algorithms developed to identify factors strongly associated with in-hospital mortality. Two models were developed; the first model included the demographic, hospital-related, and disease-related items described above, as well as individual GFS domains and CCI items. The second model was similar to the first but replaced the GFS domains and CCI items with the HFRS as a global measure of frailty. Model performance was assessed using the area under the receiver operating characteristic (AUROC) curve and measures of model accuracy. RESULTS: In total, 215,831 patients were included. The model using the individual GFS domains and CCI items had an AUROC curve for in-hospital mortality of 90% and a predictive accuracy of 83%. The model using the HFRS had similar performance (AUROC curve 90%, predictive accuracy 82%). The most important frailty items in the GFS were dementia/delirium, falls/fractures, and pressure ulcers/weight loss. The most important comorbidity items in the CCI were cancer, heart failure, and renal disease. CONCLUSIONS: The physical manifestations of frailty and comorbidity, particularly a history of cognitive impairment and falls, may be useful in identification of patients who need additional support during hospitalization with COVID-19.

Safety of Same-Day Discharge Posterior Lumbar Decompression and/or Discectomy: An Observational Study Using Administrative Data From England.

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: Same-day discharge is widely used in many surgical specialities. If carefully planned, it can improve patient outcomes whilst using resources efficiently. We aimed to investigate the safety of same-day discharge following a posterior lumbar decompression and/or discectomy (PLDD). METHODS: This was a retrospective analysis of administrative data. We extracted data from the Hospital Episodes Statistics database for the 5 years from 1st April 2014 to 31st March 2019. Patients undergoing an elective one or two level PLDD aged 19-54 years during the index stay were included. The primary exposure variable was same-day discharge or post-surgery overnight stay and the primary outcome was emergency hospital readmission within 90 days post-discharge. RESULTS: Data were available for 45,814 PLDD performed across 103 hospital trusts of which 7914 (17.3%) were performed as same-day discharge. Same-day discharge rates varied from 87.7% to 0% across the 90 hospital trusts that operated on more than 50 patients during the study period. Fourteen (15.6%) trusts had same-day discharge rates above 30% and 57 (63.3%) trusts had same-day discharge rates below 10%. The odds of emergency hospital readmission within 90 days were lower for same-day discharge patients (odds ratio .72 (95% confidence interval .61 to .85). There was no difference in outcomes for patients seen at trusts with a same-day discharge rate of ≥30% compared to trusts with a same-day discharge rate of ≤10%. CONCLUSIONS: Same-day discharge low-complexity elective PLDD is safe in adult patients below the age of 55 years. There is potential for many providers to substantially increase their rates of same-day discharge.

Data consistency in the English Hospital Episodes Statistics database.

BACKGROUND: To gain maximum insight from large administrative healthcare datasets it is important to understand their data quality. Although a gold standard against which to assess criterion validity rarely exists for such datasets, internal consistency can be evaluated. We aimed to identify inconsistencies in the recording of mandatory International Statistical Classification of Diseases and Related Health Problems, tenth revision (ICD-10) codes within the Hospital Episodes Statistics dataset in England. METHODS: Three exemplar medical conditions where recording is mandatory once diagnosed were chosen: autism, type II diabetes mellitus and Parkinson's disease dementia. We identified the first occurrence of the condition ICD-10 code for a patient during the period April 2013 to March 2021 and in subsequent hospital spells. We designed and trained random forest classifiers to identify variables strongly associated with recording inconsistencies. RESULTS: For autism, diabetes and Parkinson's disease dementia respectively, 43.7%, 8.6% and 31.2% of subsequent spells had inconsistencies. Coding inconsistencies were highly correlated with non-coding of an underlying condition, a change in hospital trust and greater time between the spell with the first coded diagnosis and the subsequent spell. For patients with diabetes or Parkinson's disease dementia, the code recording for spells without an overnight stay were found to have a higher rate of inconsistencies. CONCLUSIONS: Data inconsistencies are relatively common for the three conditions considered. Where these mandatory diagnoses are not recorded in administrative datasets, and where clinical decisions are made based on such data, there is potential for this to impact patient care.

An observational study of vertebroplasty and kyphoplasty for osteoporotic spinal fractures: utilisation and outcomes in England using an administrative dataset.

We reviewed outcomes for vertebroplasty and balloon kyphoplasty for the surgical treatment of osteoporotic spinal fracture. Our study of 5792 vertebroplasty and 3136 balloon kyphoplasty procedures conducted in England over a 7-year period found no evidence that the patient outcomes studied were poorer for vertebroplasty than for balloon kyphoplasty. PURPOSE: To investigate use, safety and functional outcomes of vertebroplasty (VP) and balloon kyphoplasty (BKP) techniques for osteoporotic spinal fracture for patients operated on within the National Health Service in England. METHODS: This was an observational analysis of administrative data. Data were extracted from the Hospital Episodes Statistics database for the period 1st April 2011 to 31st March 2018 for all VP and BKP procedures. Patients aged < 19 years, with metastatic carcinoma and undergoing other decompression procedures, were excluded. The primary outcome was repeat spinal surgery within 1 year. Secondary outcomes were 30-day emergency readmission, death within 1 year, extended hospital stay, post-procedural pain within 30 days and post-procedural haemorrhage or infection within 30 days. Multilevel, multivariable logistic regression was used to adjust for covariates. RESULTS: Data were available for 5792 VP and 3136 BKP patients operated on at 96 hospital trusts. In the 63 trusts that conducted more than 20 procedures during the study period, the proportion of procedures conducted as BKP varied from 0 to 100%. There was no difference in any of the outcomes between VP and BKP patients or between trusts performing ≥ 70% and ≤ 30% of procedures as BKP. CONCLUSIONS: With regard to the outcomes studied, there is no evidence that VP is associated with poorer outcomes than BKP.

Volume-Outcome Associations for Parathyroid Surgery in England: Analysis of an Administrative Data Set for the Getting It Right First Time Program.

Importance: Previous studies have suggested an association between surgical volume and patient outcomes for parathyroid surgery. However, most previous studies are relatively small and the literature is dominated by studies form the US, which might not be readily generalizable to other settings. Objective: To investigate volume-outcome associations for parathyroid surgery in England. Design, Setting, and Participants: Cohort study that included all National Health Service hospital trusts in England with secondary analysis of administrative data using International Statistical Classification of Diseases and Related Health Problems, Tenth Revision (ICD-10). Participants included all adult, elective hospital admissions for parathyroid surgery without a diagnosis of multiple endocrine neoplasia, parathyroid cancer, or kidney disease over a 5-year period (April 2014-March 2019 inclusive). Exposures: The number of procedures conducted in the year prior to the index procedure by each surgeon and each hospital trust. Main Outcomes and Measures: Repeat parathyroid surgery within 1 year of the index procedure. Results: This study included data for 17 494 participants who underwent parathyroidectomies conducted across 125 hospital trusts. The median (IQR) age of patients was 62 (53-71) years, and 13 826 were female (79.0%). Across the period, the number of surgeons conducting parathyroid surgery changed little (280 in 2014-2015 and 2018-2019), although the number of procedures conducted rose from 3331 to 3848 per annum. Repeat parathyroid surgery at 1 year was significantly associated with surgeon volume (odds ratio [OR], 0.99; 95% CI, 0.98-0.99), but not trust volume, in the previous 12 months. Extended length of stay (OR, 0.98; 95% CI, 0.98-0.99), hypoparathyroidism/calcium disorder (OR, 1.0; 95% CI, 0.99-1.0), and postprocedural complications (OR, 0.99; 95% CI, 0.99-1.0) were also associated with lower surgeon volume. Conclusions and Relevance: In this cohort study, higher surgeon annual volume was associated with decreased rates of repeat parathyroid surgery. A minimum volume threshold of 20 procedures per annum should improve patient outcomes, although possible negative effects on access to services should be monitored.

Utilisation of tracheostomy in patients with COVID-19 in England: Patient characteristics, timing and outcomes.

OBJECTIVES: We aimed to characterise the use of tracheostomy procedures for all COVID-19 critical care patients in England and to understand how patient factors and timing of tracheostomy affected outcomes. DESIGN: A retrospective observational study using exploratory analysis of hospital administrative data. SETTING: All 500 National Health Service hospitals in England. PARTICIPANTS: All hospitalised COVID-19 patients aged ≥18 years in England between 1 March and 31 October 2020 were included. MAIN OUTCOMES AND MEASURES: This was a retrospective exploratory analysis using the Hospital Episode Statistics administrative data set. Multilevel modelling was used to explore the relationship between demographic factors, comorbidity and use of tracheostomy and the association between tracheostomy use, tracheostomy timing and the outcomes. RESULTS: In total, 2200 hospitalised COVID-19 patients had a tracheostomy. Tracheostomy utilisation varied across the study period, peaking in April-June 2020. In multivariable modelling, for those admitted to critical care, tracheostomy was most common in those aged 40-79 years, in males and in people of Black and Asian ethnic groups and those with a history of cerebrovascular disease. In critical care patients, tracheostomy was associated with lower odds of mortality (OR: 0.514 [95% CI 0.443 to 0.596], but greater length of stay OR: 41.143 [95% CI 30.979 to 54.642]). In patients that survived, earlier timing of tracheostomy (≤14 days post admission to critical care) was significantly associated with shorter length of stay. CONCLUSIONS: Tracheostomy is safe and advantageous for critical care COVID-19 patients. Early tracheostomy may be associated with better outcomes, such as shorter length of stay, compared to late tracheostomy.

COVID-19 hospital activity and in-hospital mortality during the first and second waves of the pandemic in England: an observational study.

INTRODUCTION: We aimed to examine the profile of, and outcomes for, all people hospitalised with COVID-19 across the first and second waves of the pandemic in England. METHODS: This was an exploratory retrospective analysis of observational data from the Hospital Episode Statistics data set for England. All patients aged ≥18 years in England with a diagnosis of COVID-19 who had a hospital stay that was completed between 1 March 2020 and 31 March 2021 were included. In-hospital mortality was the primary outcome of interest. The second wave was identified as starting on 1 September 2020. Multilevel logistic regression modelling was used to investigate the relationship between mortality and demographic, comorbidity and temporal covariates. RESULTS: Over the 13 months, 374 244 unique patients had a diagnosis of COVID-19 during a hospital stay, of whom 93 701 (25%) died in hospital. Adjusted mortality rates fell from 40%-50% in March 2020 to 11% in August 2020 before rising to 21% in January 2021 and declining steadily to March 2021. Improvements in mortality rates were less apparent in older and comorbid patients. Although mortality rates fell for all ethnic groups from the first to the second wave, declines were less pronounced for Bangladeshi, Indian, Pakistani, other Asian and black African ethnic groups. CONCLUSIONS: There was a substantial decline in adjusted mortality rates during the early part of the first wave which was largely maintained during the second wave. The underlying reasons for consistently higher mortality risk in some ethnic groups merits further study.

An observational study of volume-outcome effects for robot-assisted radical prostatectomy in England.

OBJECTIVES: To investigate volume-outcome relationships in robot-assisted radical prostatectomy (RARP) for cancer using data from the Hospital Episodes Statistics (HES) database for England. MATERIALS AND METHODS: Data for all adult, elective RPs for cancer during the period January 2013-December 2018 (inclusive) were extracted from the HES database. The HES database records data on all National Health Service (NHS) hospital admissions in England. Data were extracted for the NHS trust and surgeon undertaking the procedure, the surgical technique used (laparoscopic, open or robot-assisted), hospital length of stay (LOS), emergency readmissions, and deaths. Multilevel modelling was used to adjust for hierarchy and covariates. RESULTS: Data were available for 35 629 RPs (27 945 RARPs). The proportion of procedures conducted as RARPs increased from 53.2% in 2013 to 92.6% in 2018. For RARP, there was a significant relationship between 90-day emergency hospital readmission (primary outcome) and trust volume (odds ratio [OR] for volume decrease of 10 procedures: 0.99, 95% confidence interval [CI] 0.99-1.00; P = 0.037) and surgeon volume (OR for volume decrease of 10 procedures: 0.99, 95% CI 0.99-1.00; P = 0.013) in the previous year. From lowest to highest volume category there was a decline in the adjusted proportion of patients readmitted as an emergency at 90 days from 10.6% (0-49 procedures) to 7.0% (≥300 procedures) for trusts and from 9.4% (0-9 procedures) to 8.3% (≥100 procedures) for surgeons. LOS was also significantly associated with surgeon and trust volume, although 1-year mortality was associated with neither. CONCLUSIONS: There is evidence of a volume-outcome relationship for RARP in England and minimising low-volume RARP will improve patient outcomes. Nevertheless, the observed effect size was relatively modest, and stakeholders should be realistic when evaluating the likely impact of further centralisation at a population level.

Centre variation in mortality following post-hospitalization acute kidney injury: analysis of a large national cohort.

BACKGROUND: Routine monitoring of outcomes for patients with acute kidney injury (AKI) is important to drive ongoing quality improvement in patient care. In this study we describe the development of a case mix-adjusted 30-day mortality indicator for patients with post-hospitalization AKI (PH-AKI) across England to facilitate identification of any unwarranted centre variation in outcomes. METHODS: We utilized a routinely collected national dataset of biochemically detected AKI cases linked with national hospitals administrative and mortality data. A total of 250 504 PH-AKI episodes were studied across 103 National Health Service hospital trusts between January 2017 and December 2018. Standardized mortality ratios (SMRs) were calculated for each trust using logistic regression, adjusting for age, sex, primary diagnosis, comorbidity score, AKI severity, month of AKI and admission method. RESULTS: The mean 30-day mortality rate was high, at 28.6%. SMRs for 23/103 trusts were classed as outliers, 12 above and 11 below the 95% confidence limits. Patients with PH-AKI had mortality rates >5 times higher than the overall hospitalized population in 90/136 diagnosis groups and >10 times higher in 60/136 groups. Presentation at trusts with a co-located specialist nephrology service was associated with a lower mortality risk, as was South Asian or Black ethnicity. Deprivation, however, was associated with higher mortality. CONCLUSIONS: This is the largest multicentre analysis of mortality for patients with biochemically ascertained PH-AKI to date, demonstrating once again the considerable risk associated with developing even mild elevations in serum creatinine. Mortality rates varied considerably across centres and those identified as outliers will now need to carefully interrogate local care pathways to understand and address the reasons for this, with national policy required to tackle the identified health disparities.

The volume and outcome relationship for thyroidectomy in England.

PURPOSE: The delivery of surgical care in England has seen a momentum towards centralisation within larger volume hospitals and surgical teams. The aim of this study was to investigate outcomes in England in relationship to hospital and surgeon annual volumes for total thyroidectomy. METHODS: Data were extracted from the Hospital Episodes Statistics (HES) database for England. A 6-year period (April 2012-March 2018 inclusive) for all adult admissions for thyroidectomy was used in the analysis. The primary outcome measure used was a length of hospital stay greater than 2 days or an emergency readmission within 30 days following surgery. This was used as a proxy for surgical complications. A multilevel modelling strategy was used to adjust for hierarchy and potentially confounding. RESULTS: Data for 22,823 total thyroidectomies across 144 hospital trusts were used for analysis. For total thyroidectomy, larger volume surgeons had reduced levels of post-surgical complications; length of stay > 2 and > 4 days; emergency readmission at 30 days; and hypoparathyroidism, vocal cord palsy, stridor, and tracheostomy at 1-year post-surgery. Larger hospital volume was associated with lower levels of emergency readmission at 30 days and hypoparathyroidism at 1 year. CONCLUSIONS: There is significant correlation between surgeon volume and clinical outcome for total thyroidectomy. The relationship was approximately linear, and a low-volume threshold could not be defined.

Variability in COVID-19 in-hospital mortality rates between national health service trusts and regions in England: A national observational study for the Getting It Right First Time Programme.

BACKGROUND: A key first step in optimising COVID-19 patient outcomes during future case-surges is to learn from the experience within individual hospitals during the early stages of the pandemic. The aim of this study was to investigate the extent of variation in COVID-19 outcomes between National Health Service (NHS) hospital trusts and regions in England using data from March-July 2020. METHODS: This was a retrospective observational study using the Hospital Episode Statistics administrative dataset. Patients aged ≥ 18 years who had a diagnosis of COVID-19 during a hospital stay in England that was completed between March 1st and July 31st, 2020 were included. In-hospital mortality was the primary outcome of interest. In secondary analysis, critical care admission, length of stay and mortality within 30 days of discharge were also investigated. Multilevel logistic regression was used to adjust for covariates. FINDINGS: There were 86,356 patients with a confirmed diagnosis of COVID-19 included in the study, of whom 22,944 (26.6%) died in hospital with COVID-19 as the primary cause of death. After adjusting for covariates, the extent of the variation in-hospital mortality rates between hospital trusts and regions was relatively modest. Trusts with the largest baseline number of beds and a greater proportion of patients admitted to critical care had the lowest in-hospital mortality rates. INTERPRETATION: There is little evidence of clustering of deaths within hospital trusts. There may be opportunities to learn from the experience of individual trusts to help prepare hospitals for future case-surges.

Changes in COVID-19 in-hospital mortality in hospitalised adults in England over the first seven months of the pandemic: An observational study using administrative data.

BACKGROUND: Previous research by our team identified factors associated with in-hospital mortality in patients with a diagnosis of COVID-19 in England between March and May 2020. The aim of the current paper was to investigate the changing role of demographics and co-morbidity, with a particular focus on ethnicity, as risk factors for in-hospital mortality over an extended period. METHODS: This was a retrospective observational study using the Hospital Episode Statistics administrative dataset. All patients aged ≥ 18 years in England with a diagnosis of COVID-19 who had a hospital stay that was completed (discharged alive or died) between 1st March and 30th September 2020 were included. In-hospital mortality was the primary outcome of interest. Multilevel logistic regression was used to model the relationship between in-hospital mortality with adjustment for the covariates: age, sex, deprivation, ethnicity, date of discharge and a number of comorbidities. FINDINGS: Compared to patients in March-May (n = 93,379), patients in June-September (n = 24,059) were younger, more likely to be female and of Asian ethnicity, but less likely to be of Black ethnicity. In-hospital mortality rates, adjusted for covariates, declined from 33-34% in March to 11-12% in September. Compared to the March-May period, Bangladeshi, Indian and Other Asian ethnicity patients had a lower relative odds of death (compared to White ethnicity patients) during June-September. For Pakistani patients, the decline in-hospital mortality rates was more modest across the same time periods with the relative odds of death increasing slightly (odds ratio (95% confidence interval)) 1.24 (1.10 to 1.40) and 1.35 (1.08 to 1.69) respectively. From March-May to June-September the relative odds of death in patients with a diagnosis of metastatic carcinoma increased (1.90 (1.73 to 2.08) vs 3.01 (2.55 to 3.54)) but decreased for male patients (1.44 (1.39 to 1.49) vs 1.27 (1.17 to 1.38)) and patients with obesity (1.42 (1.34 to 1.52) vs 0.97 (0.83 to 1.14)) and diabetes without complications (1.14 (1.10 to 1.19) vs 0.95 (0.87 to 1.05)). INTERPRETATION: In-hospital mortality rates for patients with a diagnosis of COVID-19 have fallen substantially and there is evidence that the relative importance of some covariates has changed since the start of the pandemic. These patterns should continue to be tracked as new variants of the virus emerge, vaccination programmes are rolled out and hospital pressures fluctuate.

Patient factors and temporal trends associated with COVID-19 in-hospital mortality in England: an observational study using administrative data.

BACKGROUND: Analysis of the effect of COVID-19 on the complete hospital population in England has been lacking. Our aim was to provide a comprehensive account of all hospitalised patients with COVID-19 in England during the early phase of the pandemic and to identify the factors that influenced mortality as the pandemic evolved. METHODS: This was a retrospective exploratory analysis using the Hospital Episode Statistics administrative dataset. All patients aged 18 years or older in England who completed a hospital stay (were discharged alive or died) between March 1 and May 31, 2020, and had a diagnosis of COVID-19 on admission or during their stay were included. In-hospital death was the primary outcome of interest. Multilevel logistic regression was used to model the relationship between death and several covariates: age, sex, deprivation (Index of Multiple Deprivation), ethnicity, frailty (Hospital Frailty Risk Score), presence of comorbidities (Charlson Comorbidity Index items), and date of discharge (whether alive or deceased). FINDINGS: 91 541 adult patients with COVID-19 were discharged during the study period, among which 28 200 (30·8%) in-hospital deaths occurred. The final multilevel logistic regression model accounted for age, deprivation score, and date of discharge as continuous variables, and sex, ethnicity, and Charlson Comorbidity Index items as categorical variables. In this model, significant predictors of in-hospital death included older age (modelled using restricted cubic splines), male sex (1·457 [1·408-1·509]), greater deprivation (1·002 [1·001-1·003]), Asian (1·211 [1·128-1·299]) or mixed ethnicity (1·317 [1·080-1·605]; vs White ethnicity), and most of the assessed comorbidities, including moderate or severe liver disease (5·433 [4·618-6·392]). Later date of discharge was associated with a lower odds of death (0·977 [0·976-0·978]); adjusted in-hospital mortality improved significantly in a broadly linear fashion, from 52·2% in the first week of March to 16·8% in the last week of May. INTERPRETATION: Reductions in the adjusted probability of in-hospital mortality for COVID-19 patients over time might reflect the impact of changes in hospital strategy and clinical processes. The reasons for the observed improvements in mortality should be thoroughly investigated to inform the response to future outbreaks. The higher mortality rate reported for certain ethnic minority groups in community-based studies compared with our hospital-based analysis might partly reflect differential infection rates in those at greatest risk, propensity to become severely ill once infected, and health-seeking behaviours. FUNDING: None.

Identifying unwarranted variation in clinical practice between healthcare providers in England: Analysis of administrative data over time for the Getting It Right First Time programme.

RATIONALE, AIMS, AND OBJECTIVES: The Getting It Right First Time programme aims to reduce variation in clinical practice that unduly impacts on outcomes for patients in the National Health Service (NHS) in England; often termed "unwarranted variation." However, there is no "gold standard" method for detecting unwarranted variation. The aim of this study was to describe a method to allow such variation in recorded practice or patient outcomes between NHS trusts to be detected using data over multiple time periods. By looking at variation over time, it was hoped that patterns that could be missed by looking at data at a single time point, or averaged over a longer time period, could be identified. METHODS: This was a retrospective time-series analysis of observational administrative data. Data were extracted from the Hospital Episodes Statistics database for two exemplar aspects of clinical practice within the field of urology: (a) use of ureteric stents on first emergency admission to treat urinary tract stones and (b) waiting times for definitive surgery for urinary retention. Data were categorized into 3-month time periods and three rules were used to detect unwarranted variation in the outcome metric relative to the national average: (a) two of any three consecutive values greater than two standard deviations above the mean, (b) four of any five consecutive values greater than one standard deviation above the mean, and (c) eight consecutive values above the mean. RESULTS: For the urinary tract stones dataset, 24 trusts were identified as having unwarranted variation in the outcomes using funnel plots and 23 trusts using the time-series method. For the urinary retention data, 18 trusted were identified as having unwarranted variation in the outcomes using funnel plots and 22 trusts using the time-series method. CONCLUSIONS: The time-series method may complement other methods to help identify unwarranted variation.

Outcomes for Angioplasty and Bypass Lower Limb Revascularisation Procedures for Limb Salvage in England: Findings From the Getting It Right First Time Programme.

OBJECTIVE: The aim of this study was to investigate outcomes for lower limb revascularisation for limb salvage within the National Health Service (NHS) in England. METHODS: This was a retrospective observational study of administrative data. Data were extracted from the Hospital Episodes Statistics database for England. Data were included for a seven year period (1 April 2011-31 March 2018 inclusive) for all patients aged ≥ 18 years receiving surgery for peripheral arterial occlusive disease. Data were extracted for patient age, sex and frailty level, the NHS trusts undertaking the procedure, the technique used (angioplasty, bypass, endarterectomy, or hybrid), the mode of admission (elective or emergency), the surgical speciality, the financial year of admission, length of hospital stay during the procedure, subsequent emergency re-admission, revascularisation procedures within 30 days and subsequent amputation and mortality within one year and within five years. The primary outcome was one year amputation free survival. For analysis, data were separated into diabetic and non-diabetic patients. Multilevel modelling was used to adjust for hierarchy and observed confounding when investigating outcomes. RESULTS: Data were available for 98 109 procedures across 124 hospital trusts. For non-diabetic patients (odds ratio 1.142, 95% confidence interval 1.068-1.222), one year amputation free survival was higher for angioplasty than for bypass. For diabetic patients, there was no difference in the primary outcome. One year amputation rates, 30 day emergency re-admission rates, and length of stay were all lower for angioplasty, and 30 day revascularisation rates were lower for bypass for both diabetic and non-diabetic patients. CONCLUSION: Outcomes were generally better for angioplasty than for bypass surgery for lower limb revascularisation for both diabetic and non-diabetic patients. The findings should be interpreted with caution given the likely different clinical presentations of those selected for each procedure. Future clinical trials may provide more definitive data.

Editor's Choice - Volume-Outcome Relationships in Elective Abdominal Aortic Aneurysm Surgery: Analysis of the UK Hospital Episodes Statistics Database for the Getting It Right First Time (GIRFT) Programme.

OBJECTIVE: To investigate whether a volume-outcome relationship exists for elective abdominal aortic aneurysm (AAA) surgery conducted within the National Health Service (NHS) in England. METHODS: This was an analysis of administrative data. Data were extracted from the Hospital Episodes Statistics database for England from April 2011 to March 2019 for all adult admissions for elective infrarenal AAA surgery. Data were extracted for the NHS trust and surgeon undertaking the procedure, the surgical technique used (open or endovascular), the financial year of admission, length of hospital and critical care stay during the procedure and subsequent emergency re-admissions (primary outcome) and deaths within 30 days. Multilevel modelling was used to adjust for hierarchy and confounding. RESULTS: A dataset of 31 829 procedures (8867 open, 22 962 endovascular) was extracted. For open surgery, lower trust annual volume was associated with higher 30 day emergency re-admission rates and higher 30 day mortality. For open surgery, lower surgeon annual volume was associated with higher 30 day mortality and length of hospital stay greater than the median. For endovascular surgery, lower surgeon annual volume was associated with not having an overnight stay in critical care. None of the other volume-outcome relationships investigated was significant. CONCLUSION: For elective infrarenal AAA surgery in the UK NHS, there was strong evidence of a volume-outcome relationship for open surgery. However, evidence for a volume-outcome relationship is dependent on the specific procedure undertaken and the outcome of interest.

Fixation Method and Subsequent Revision Rates for Elective Primary Hip Arthroplasty in People Aged 70 Years and Older: Analysis of National Administrative Data Sets by the UK Getting It Right First Time Program.

BACKGROUND: We aimed to understand the role of fixation method in predicting subsequent revision rates in people aged 70 years and older undergoing elective primary total hip arthroplasty (THA) within the UK National Health Service (NHS). METHODS: Data on elective primary THAs conducted in people aged 70 years and older between April 1, 2012, and March 31, 2018, and subsequent revisions conducted up to March 31, 2019, were extracted from the Hospital Episodes Statistics database for all NHS procedures in England. A flexible parametric competing risks model was used to identify the role of fixation method in predicting revision and adjust for age, sex, frailty, year of surgery, and all-cause mortality. RESULTS: Data were available for 190,656 procedures. Crude revision rates at 1-7 years follow-up in those who had cemented, hybrid/reverse hybrid, and uncemented fixation were 1.8%, 1.8%, and 2.3%, respectively. There was a high level of variation between NHS trusts in the proportionate use of fixation method. The differences in the hazard of revision between uncemented and cemented fixation (hazard ratio, 1.238 [95% confidence interval, 1.148-1.336]) and hybrid/reverse hybrid fixation (hazard ratio, 1.184 [95% confidence interval, 1.082-1.297]) were both significant. In secondary analysis, there was evidence that revision rates in trusts where uncemented fixation predominated were not significantly lower for uncemented fixation compared to all other fixation methods. CONCLUSIONS: Revision rates were significantly higher for elective primary THA in people aged 70 years and older who have uncemented fixation, compared to those who had cemented and hybrid/reverse hybrid fixation.