A 16-year Longitudinal Cohort Study of Incidence and Bacteriology of Necrotising Fasciitis in England.

BACKGROUND: Necrotising fasciitis (NF) is a rapidly progressive, destructive soft tissue infection with high mortality. The primary aim of this study was to evaluate the incidence and mortality of NF amongst patients admitted to English National Health Service (NHS) hospitals. The secondary aims included the identification of risk factors for mortality and causative pathogens. METHODS: The Hospital Episodes Statistics database identified patients with NF admitted to English NHS Trusts from 1/1/2002 to 31/12/2017. Information on patient demographics, co-morbid conditions, microbiology specimens, surgical intervention and in-hospital mortality was collected. Uni- and multivariable analyses were performed to investigate factors related to in-hospital mortality. RESULTS: A total of 11,042 patients were diagnosed with NF. Age-standardised incidence rose from 9 per million in 2002 to 21 per million in 2017 (annual percentage change = 6.9%). Incidence increased with age and was higher in men. Age-standardised mortality rate remained at 16% over the study period, while in-hospital mortality declined. On multivariable analysis, the following factors were associated with increased risk of in-hospital mortality: emergency admission, female sex, history of congestive heart failure, peripheral vascular disease, chronic kidney disease and cancer. Admission year and diabetes, which was significantly prevalent at 27%, were not associated with increased risk of mortality. Gram-positive pathogens, particularly Staphylococci, decreased over the study period with a corresponding increase in Gram-negative pathogens, predominantly E. coli. CONCLUSION: The incidence of NF increased markedly from 2002 to 2017 although in-hospital mortality did not change. There was a gradual shift in the causative organisms from Gram-positive to Gram-negative.

Stroke-Related Hospitalization and Mortality After a Kidney Allograft: A Population-Cohort Study.

OBJECTIVES: Stroke is a major cause of mortality in the general population but data regarding stroke-related hospitalization or mortality after a kidney transplant is limited. We determined risk for stroke-related episodes after a kidney transplant in a population-based cohort study of 19,103 kidney allograft recipients in England between 2001 and 2012. MATERIALS AND METHODS: The incidence of stroke-related events after a kidney transplant with pretransplant history of stroke, the incidence of stroke-related hospitalization or death among all kidney allograft recipients after a kidney transplant, and risk factors for stroke-related mortality after a kidney transplant were examined. Data were obtained from hospital episode statistics (an administrative data warehouse that contains admissions to all National Health Service hospitals in England) and is linked to the Office for National Statistics, which collects information on all registered deaths in England. RESULTS: There were 782 nonfatal stroke-related hospitalizations and 113 stroke-related deaths (5.4% of total deaths) after a kidney transplant (median follow-up 4.4 y after a kidney transplant). Risk for all-cause mortality was higher for those recipients with, compared to those without, a history of stroke (21.5% vs 10.8%; P < .001). However, risk for stroke-related mortality after a kidney transplant was no different. Kidney allograft recipients with nonfatal stroke episodes after a transplant were at a higher risk for all-cause and stroke-related mortality. In a Cox regression model, pretransplant history of stroke was an independent risk factor for all-cause mortality, but not stroke-related mortality, while posttransplant hospitalization with nonfatal stroke was a risk factor for both. CONCLUSIONS: Fatal and nonfatal stroke-related events are common among kidney allograft recipients. Further research is warranted to allow better risk stratification and facilitate clinical trials for risk attenuation of stroke after a kidney transplant.

National administrative data produces an accurate and stable risk prediction model for short-term and 1-year mortality following cardiac surgery.

OBJECTIVES: Various risk models exist to predict short-term risk-adjusted outcomes after cardiac surgery. Statistical models constructed using clinical registry data usually perform better than those based on administrative datasets. We constructed a procedure-specific risk prediction model based on administrative hospital data for England and we compared its performance with the EuroSCORE (ES) and its variants. METHODS: The Hospital Episode Statistics (HES) risk prediction model was developed using administrative data linked to national mortality statistics register of patients undergoing CABG (35,115), valve surgery (18,353) and combined CABG and valve surgery (8392) from 2008 to 2011 in England and tested using an independent dataset sampled for the financial years 2011-2013. Specific models were constructed to predict mortality within 1-year post discharge. Comparisons with EuroSCORE models were performed on a local cohort of patients (2580) from 2008 to 2013. RESULTS: The discrimination of the HES model demonstrates a good performance for early and up to 1-year following surgery (c-stats: CABG 81.6%, 78.4%; isolated valve 78.6%, 77.8%; CABG & valve 76.4%, 72.0%), respectively. Extended testing in subsequent financial years shows that the models maintained performance outside the development period. Calibration of the HES model demonstrates a small difference (CABG 0.15%; isolated valve 0.39%; CABG & valve 0.63%) between observed and expected mortality rates and delivers a good estimate of risk. Discrimination for the HES model for in-hospital deaths is similar for CABG (logistic ES 79.0%) and combined CABG and valve surgery (logistic ES 71.6%) patients and superior for valve patients (logistic ES 70.9%) compared to the EuroSCORE models. The C-statistics of the EuroSCORE models for longer periods are numerically lower than that of the HES model. CONCLUSION: The national administrative dataset has produced an accurate, stable and clinically useful early and 1-year mortality prediction after cardiac surgery.

Aortic dissection in pregnancy in England: an incidence study using linked national databases.

OBJECTIVES: To conduct the first population-level incidence study of aortic dissection in pregnancy using linked hospital-based data in England. SETTING: Hospital-based data (Hospital Episode Statistics (HES) linked with mortality data from the Office of National Statistics), national enquiries (Confidential Enquiries into Maternal Mortality) and surveys (UK Obstetric Surveillance System; UKOSS) of aortic dissection in pregnancy from 2003 to 2011 in England. PARTICIPANTS: Between 2003 and 2011, all female patients admitted with diagnoses of aortic dissection (not necessarily as the primary cause of admission) and of pregnancy, childbirth and puerperium, were included. OUTCOME MEASURES: Diagnosis of aortic dissection during pregnancy, operated or not operated, with outcome of death or live patient from 2003 to 2011 in England. RESULTS: There were significant differences in characteristics of databases with respect to study population, time of study, recorded event and follow-up of outcomes. On the basis of HES, annual incidence of aortic dissection was 1.23 (95% CI 1.22 to 1.24) per 100 000 maternities. Incidence of aortic dissection with death within 1 year was 0.30 (0.29 to 0.31) per 100 000 maternities. Incidence of aortic dissection increased from 0.74 (0.73 to 0.75) per 100 000 maternities in 2003-2005 to 1.52 (1.51 to 1.53) per 100 000 maternities in 2009-2011. In the Confidential Enquiries into Maternal Deaths, incidence of deaths was highest for 2003-2005 (0.43/100 000 maternities) and lowest for 1997-1999 (0.21/100 000 maternities). In the UK Obstetric Surveillance System, national incidence of aortic dissection was 0.80 (0.50 to 1.50) per 100 000 maternities between 2009 and 2011. CONCLUSIONS: The case of aortic dissection in pregnancy illustrates data limitations regarding complications in pregnancy from different sources in the UK, even for a diagnosis with seemingly few alternative coding and diagnostic possibilities. These limitations should be acknowledged when estimating incidence and outcome.

Acute Care QUAliTy in chronic Kidney disease (ACQUATIK): a prospective cohort study exploring outcomes of patients with chronic kidney disease.

INTRODUCTION: Chronic kidney disease (CKD) is common and carries a high risk of morbidity, including hospital admissions and readmissions and mortality. This is largely attributed to an increased risk of cardiovascular disease. Patients with CKD are less likely to receive evidence-based treatments for cardiovascular disease. However, these treatments are based on trials which generally exclude patients with CKD. It is therefore unclear whether this patient group derives the same benefits without an increased risk of adverse effects. METHODS AND ANALYSIS: The Acute Care QUAliTy in chronic Kidney disease (ACQUATIK) study is a prospective, observational, multicentre cohort study. Over 4000 patients will be recruited with an enrolment period of 2 years and a follow-up period of 2-4 years. Patients under follow-up by a renal team will be excluded. Data will be obtained from patient and hospital records during the index admission. Preadmission data will be extracted from general practice records based on the Quality and Outcomes Framework. Diagnosis, comorbidities and procedure data pertaining to the index and subsequent admissions will be extracted from the Hospital Episode Statistics database and long-term mortality data will be tracked using the Office of National Statistics. This information will allow us to examine a complete patient journey through primary and secondary care, providing unequalled levels of information on treatment and outcomes of patients with CKD. The combined data set will be used to compare outcomes and treatments among patients with CKD versus patients without CKD. The primary end point is hospital readmission rates. The relationship between age, sex, ethnicity, socioeconomic status and concurrent comorbidities will be analysed to determine their influence on outcomes and treatments. ETHICS AND DISSEMINATION: The ACQUATIK study has been approved by the NRES Committee West Midlands-South Birmingham-Reference 13/WM/0317. The results from ACQUATIK will be submitted for publication in peer-reviewed journals and presented at primary and secondary care conferences. TRIAL REGISTRATION NUMBER: ISRCTN37237454.

Population level analysis of diagnostic laparoscopy versus normal appendicectomy for acute lower abdominal pain.

BACKGROUND: There is virtually no evidence to guide surgeons and patients when faced with an absence of pathology for acute lower abdominal pain. This study aimed to compare diagnostic laparoscopy alone to laparoscopic removal of a normal appendix in patients with acute lower abdominal pain but an absence of pathology. METHOD: Retrospective analysis of routinely collected hospital data from all English acute hospitals performing emergency appendicectomy between 01/04/2002 and 31/03/2012. Patients admitted as emergencies with lower abdominal pain undergoing diagnostic laparoscopy (with no other procedure or associated diagnosis) were compared to those undergoing laparoscopic normal appendicectomy. The primary outcome measure was emergency readmission for abdominal pain during the 12 period after index surgery. Multivariable binary logistic regression was used to produce adjusted odds ratios (OR and bootstrapped 95% confidence intervals). RESULT: 10,072 patients undergoing diagnostic laparoscopy were compared to 9665 undergoing laparoscopic normal appendicectomy. Overall, 32.9% (n = 6499/19,737) were readmitted as an emergency for abdominal pain during the 12 months after index surgery. Following risk-adjustment, laparoscopic normal appendicectomy was associated with 44% reduced odds of readmission (adjusted OR 0.56, 0.50-61). In the diagnostic laparoscopy group, 2.1% of patients (213) required subsequent appendicectomy, which was abnormal in 47.4% (101/213) cases. CONCLUSION: This study suggests that removal of a laparoscopically normal appendix, when no other pelvic pathology is visible, may reduce one-year readmission rates. Although limited through selection bias from routinely collected data, this study provides evidence for practicing surgeons and information for methodologists to power a future trial.

Malignancy-related mortality following kidney transplantation is common.

There is a paucity of studies describing malignancy-related mortality after kidney transplantation. To help quantify this, we extracted data for all kidney-alone transplant procedures performed in England between April 2001 and March 2012. Data linkage analysis was performed between Hospital Episode Statistics and the Office for National Statistics to identify all deaths occurring in this cohort. Among 19,103 kidney transplant procedures analyzed (median follow-up 4.4 years), 2085 deaths occurred, of which 376 (18.0%) were due to malignancy (crude mortality rate 361 malignancy-related deaths per 100,000 person-years). Common sites of malignancy-related death were lymphoma (18.4%), followed by lung (17.6%) and renal (9.8%), with 14.1% unspecified. The risk of malignancy-related death increased with age: under 50 (0.8%), 50-59 (2.5%), 60-69 (4.8%), 70-79 (6.5%) and over 80 years (9.1%). Age- and gender-stratified malignancy-related mortality risk difference was higher in the transplant compared with the general population. Cox proportional hazard models identified increased age, pretransplant history of malignancy and deceased-donor kidney transplantation to be independently associated with risk for post-transplant death from malignancy. Thus, malignancy as a cause of post-kidney transplantation death is common and requires heightened surveillance.

Recipient age and risk for mortality after kidney transplantation in England.

BACKGROUND: The aim of this study was to explore age-related mortality post-kidney transplantation in England over the last decade. METHODS: This study used data from Hospital Episode Statistics to select all kidney transplant procedures performed in England between April 2001 and March 2012. Demographics and medical comorbidities (based upon ICD-10 codes) were extracted at baseline. Data linkage analysis was performed with the Office for National Statistics to identify all deaths occurring among this study cohort. RESULTS: Data for 19,103 kidney transplant procedures was analyzed, with a median follow-up of 4.4 years (interquartile range 2.2-7.3 years). Categorization of age cohorts at time of transplantation were age below 50 (n=11,421, 59.8%), 50 to 59 (n=4,195, 22.0%), 60 to 69 (n=2,887, 15.1%), 70 to 79 (n=589, 3.1%), and 80 and above (n=11, 0.1%). There were 2,085 deaths that occurred among the study cohort during follow-up and mortality risk increased with age: below 50 (5.8%), 50 to 59 (14.2%), 60 to 69 (22.0%), 70 to 79 (31.9%), and 80 and above (45.5%). The three most common causes of deaths for recipients 70 and over were cardiac (21.2%), infection (21.2%), and malignancy (20.2%), respectively. Lower mortality was observed with the receipt of a living-donor kidney for recipients aged 70 and above. On Cox regression analysis, risk for death increased with each additional decade of recipient age over 50. CONCLUSION: Increasing age is a strong, independent risk factor for death after kidney transplantation. Although lower mortality was observed with living kidney transplantation among elderly recipients, living-donor rates decrease with increasing recipient age. Pretransplant counseling and posttransplant tailored immunosuppression should be explored, the latter requiring targeted clinical trials.

Long-term effectiveness of cholecystectomy and endoscopic sphincterotomy in the management of gallstone pancreatitis.

BACKGROUND: Gallstone pancreatitis (GSP) is a common condition, accounting for 30-40 % of all pancreatitis cases. All GSP patients should undergo definitive treatment to prevent further attacks. This study aimed to investigate the long-term outcome after definitive treatment in England by cholecystectomy, endoscopic sphincterotomy (ES), or both. METHODS: Hospital episode statistics data were used to identify patients admitted for the first time with GSP between January and December 2005. These patients were followed for 18 months to identify those who underwent definitive treatment. Treatment groups then were followed until December 2010 to identify readmissions with a further GSP attack as an emergency or admissions with complications of gallstone disease. RESULTS: 5,079 patients admitted with a first bout of GSP between January and December 2005. The in-hospital mortality rate was 7.8 %. Of those who survived the initial attack, 2,511 went on to have a cholecystectomy, 419 had an ES alone, and 496 had ES followed by cholecystectomy. Recurrent pancreatitis after definitive treatment was more common among patients treated with ES (6.7 %) than among those treated with cholecystectomy (4.4 %) or ES followed by cholecystectomy (1.2 %) (p < 0.05). Admissions with other complications attributable to gallstones in patients treated with ES alone were similar to those seen in patients who had received no definitive treatment (12.2 vs. 9.4 %). CONCLUSIONS: Cholecystectomy offers better protection than ES against further bouts of pancreatitis in patients with GSP, but ES is an acceptable alternative. Interval cholecystectomy in patients treated initially with ES was the most effective method of preventing further pancreatitis, and the patients who underwent treatment by ES alone remained at risk of readmission with gallstone-related problems. Patients who have undergone ES and are fit for surgery should have a cholecystectomy.

Mortality after pediatric kidney transplantation in England--a population-based cohort study.

The aim of this study was to explore mortality after pediatric kidney transplantation in England over the last decade. We used data from HES to select all kidney transplant procedures performed in England between April 2001 and March 2012. Data linkage analysis was performed with the ONS to identify all deaths occurring among this study cohort. Data for 1189 pediatric recipients were compared to 17 914 adult recipients (number of deaths, 33 vs. 2052, respectively, p < 0.001), with median follow-up 4.4 yr (interquartile range 2.2-7.3 yr). There was no difference in mortality within the pediatric cohort; age 0-1 (n = 25, patient survival 100.0%), age 2-5 (n = 198, patient survival 96.0%), age 6-12 (n = 359, patient survival 97.5%), and age 13-18 (n = 607, patient survival 97.4%), respectively (p = 0.567). The most common causes of death were renal (n = 8, 24.2%), infection (n = 6, 18.2%), and malignancy (n = 5, 15.2%). All deaths from malignancy were secondary to PTLD. In a fully adjusted Cox regression model, only white ethnicity was significantly associated with risk of pediatric mortality post-kidney transplantation (hazard ratio 2.7, 95% confidence interval [1.0-7.3], p = 0.047). To conclude, this population-based cohort study confirms low mortality after pediatric kidney transplantation with short follow-up.

Death within the first year after kidney transplantation--an observational cohort study.

The risk of death within the first year postkidney transplantation is not well described in the contemporary era. We extracted data on all kidney transplant procedures performed in England between April 2001 and March 2012. Data linkage analysis was performed between Hospital Episode Statistics and the Office for National Statistics to identify all deaths. Cox proportional hazard models were performed to identify factors associated with 1-year mortality. 566 deaths (3.0%) occurred within the first year post-transplant (from 19,103 kidney transplant procedures analysed). Infection, cardiovascular events and malignancy were classified in 21.6%, 18.3% and 7.4% of death certificates, respectively. Among recipients with prior myocardial infarct history who died within the first year, 38.8% of deaths were attributed to a cardiac-related event. Malignancy-related death was responsible for 61.5% of 1-year mortality for allograft recipients with pretransplant cancer history. 22.1% of deaths included kidney failure as a contributory factor on the death certificate (3.3% specifically stated allograft failure). Variables associated with 1-year mortality included deceased-donor kidney, increasing age, residence in socioeconomically deprived area and history of select medical comorbidities pre-operatively. We conclude 1-year mortality postkidney transplantation is low, but in select allograft recipients, the risk of death increases considerably.

Infection-related mortality is higher for kidney allograft recipients with pretransplant diabetes mellitus.

AIMS/HYPOTHESIS: The risk of infection-related mortality in kidney allograft recipients with pre-existing diabetes mellitus is unknown. We determined the risk of infection-related mortality after kidney transplantation in a population-based cohort stratified by diagnosis of pre-existing diabetes mellitus. METHODS: We linked data between two national registries (Hospital Episode Statistics and the Office for National Statistics) to select all mortality events after kidney transplantation in England between April 2001 and March 2012. The primary outcome measure was infection-related mortality after transplantation comparing diabetic with non-diabetic recipients. RESULTS: A total of 19,103 kidney allograft recipients were analysed; 2,968 (15.5%) were known to have diabetes before kidney transplantation. After transplantation, 2,085 deaths (10.9%) occurred (median follow-up 4.4 years [interquartile range 2.2-7.3]), with 434 classified as secondary to infection (20.8% of all deaths). Risk of overall (16.0% vs 10.0%, p < 0.001) and infection-related (3.3% vs 2.1%, p < 0.001) mortality after kidney transplantation was higher for diabetic than non-diabetic recipients, respectively. No cytomegalovirus-related deaths occurred in diabetic recipients compared with 5.7% in non-diabetic recipients (p < 0.007), with a trend towards more unspecified sepsis in diabetic recipients (30.6% vs 22.6%, respectively, p = 0.070). Diabetes at the time of transplantation was an independent risk factor predicting infection-related mortality in kidney allograft recipients after transplantation (HR 1.71 [95% CI 1.36, 2.15], p < 0.001). CONCLUSIONS/INTERPRETATION: Infection-related mortality is more common in kidney allograft recipients with pre-existing diabetes mellitus. Further work is required to determine whether attenuated immunosuppression is beneficial for diabetic kidney allograft recipients.

Fatal venous thromboembolism associated with hospital admission: a cohort study to assess the impact of a national risk assessment target.

OBJECTIVES: In 2010, the Department of Health in England introduced an incentivised national target for National Health Service (NHS) hospitals aiming to increase the number of patients assessed for the risk of developing venous thromboembolism (VTE) associated with hospital admission. We assessed the impact of this initiative on VTE mortality and subsequent readmission with non-fatal VTE. DESIGN: Observational cohort study. PATIENTS: All patients admitted to NHS hospitals in England between July 2010 and March 2012. INTERVENTIONS: An NHS hospital which assessed at least 90% of patient admissions achieved the quality standard. MAIN OUTCOME MEASURES: The principal outcome measured was death from VTE up till 90 days after hospital discharge using linked Office of National Statistics and Hospital Episode Statistics data. RESULTS: In the principal analyses of patients admitted to hospital for more than 3 days, there was a statistically significant reduction in VTE deaths in hospitals achieving 90% VTE risk assessment: relative risk (RR) 0.85 (95% CI 0.75 to 0.96; p=0.011) for VTE as the primary cause of death. In supportive analyses of postdischarge deaths after index admissions of up to 3 days, there was also a reduction in fatal VTE RR 0.61 (0.48 to 0.79; p=0.0002). This effect was seen for both surgical and non-surgical patients. No effect was seen in day case admissions. There was no change in non-fatal VTE readmissions up to 90 days after discharge. CONCLUSIONS: A national quality initiative to increase the number of hospitalised patients assessed for risk of VTE has resulted in a reduction in VTE mortality.

Socioeconomic deprivation is independently associated with mortality post kidney transplantation.

The association between area socioeconomic deprivation and mortality post kidney transplantation is unclear. To clarify this, we obtained data from 19,103 kidney transplant procedures performed in England from April 2001 to March 2012. Patient demographics included age, gender, donor type (living or deceased), ethnicity, transplant year, allograft failure, medical comorbidities, and area socioeconomic deprivation (Index of Multiple Deprivation (2010)). Primary and secondary outcome measures were 1- and 5-year mortality with Cox proportional hazard models performed to identify independent factors associated with mortality. Data were broken down into quintiles of patients by area socioeconomic deprivation 1 to 5 (most to least deprived, respectively). At 1 year post transplant, 566 deaths were recorded, with infection being the most common cause of death. Compared with the most deprived individuals (reference point), the least deprived recipients had significantly decreased risk of death at 1 and 5 years post kidney transplant (hazard ratio 0.66, 95% CI (0.57-0.76) and hazard ratio 0.65, 95% CI (0.54-0.77), respectively). Thus, socioeconomic deprivation is independently associated with increased mortality post kidney transplantation.