title: Mortality following acute pancreatitis: social deprivation, hospital size and time of admission: record linkage study.
abstract: BACKGROUND
  Very little is known about whether mortality following acute pancreatitis may be influenced by the following five factors: social deprivation, week day of admission, recruitment of junior doctors in August each year, European Working Time Directives (EWTDs) for junior doctors' working hours and hospital size. The aim of this study was to establish how mortality following acute pancreatitis may be influenced by these five factors in a large cohort study.
  
  
  METHODS
  Systematic record linkage of inpatient, mortality and primary care data for 10 589 cases of acute pancreatitis in Wales, UK (population 3.0 million), from 1999 to 2010. The main study outcome measure was mortality at 60 days following the date of admission.
  
  
  RESULTS
  Mortality was 6.4% at 60 days. There was no significant variation in mortality according to social deprivation or the week day of admission. There was also no significant variation according to calendar month for acute pancreatitis overall or for gallstone aetiology, but for alcoholic acute pancreatitis, mortality was increased significantly by 93% for admissions during the months of August and September and 102% from August to October when compared with all other calendar months. Mortality was increased significantly for alcoholic aetiology in August 2004, the official month that the first EWTD was implemented, but there were no other increases following the first or second EWTDs. There were also indications of increased mortality in large hospitals when compared with small hospitals, for acute pancreatitis overall and for gallstone aetiology but not for alcoholic acute pancreatitis, although these increases in mortality were of quite marginal significance.
  
  
  CONCLUSIONS
  Although we found some evidence of increased mortality for patients admitted with alcoholic acute pancreatitis during August to October, in August 2004, and in large hospitals for acute pancreatitis overall and for gallstone aetiology, the study factors had limited impact on mortality following acute pancreatitis and no significant impact when adjusted for multiple comparisons.
authors.affiliation: College of Medicine, Swansea University, Singleton Park, Swansea, UK. stephen.e.roberts@swansea.ac.uk.
authors.forename: Stephen E
authors.initials: SE
authors.lastname: Roberts
authors.forename: Kymberley
authors.initials: K
authors.lastname: Thorne
authors.forename: P Adrian
authors.initials: PA
authors.lastname: Evans
authors.forename: Ashley
authors.initials: A
authors.lastname: Akbari
authors.forename: David G
authors.initials: DG
authors.lastname: Samuel
authors.forename: John G
authors.initials: JG
authors.lastname: Williams
mesh_terms: D000208:Acute Disease; D000328:Adult; D000368:Aged; D015331:Cohort Studies; D004522:Educational Status; D004651:Employment; D005260:Female; D006276:Health Facility Size / Q000706:statistics & numerical data; D006297:Health Services Accessibility; D006760:Hospitalization / Q000706:statistics & numerical data*; D006798:Housing; D006801:Humans; D007182:Income; D008297:Male; D008498:Medical Record Linkage; D008505:Medical Staff, Hospital / Q000706:statistics & numerical data; D008875:Middle Aged; D010195:Pancreatitis / Q000401:mortality*; D012111:Residence Characteristics / Q000706:statistics & numerical data*; D012307:Risk Factors; D013997:Time Factors; D014852:Wales; D014940:Work Schedule Tolerance