title: Exploring Potential Reasons for the Temporal Trend in Dialysis-Requiring AKI in the United States.
abstract: OBJECTIVE
  The population incidence of dialysis-requiring AKI has risen substantially in the last decade in the United States, and factors associated with this temporal trend are not well known.
  
  
  METHODS
  We conducted a retrospective cohort study using data from the Nationwide Inpatient Sample, a United States nationally representative database of hospitalizations from 2007 to 2009. We used validated International Classification of Diseases, Ninth Revision codes to identify hospitalizations with dialysis-requiring AKI and then, selected the diagnostic and procedure codes most highly associated with dialysis-requiring AKI in 2009. We applied multivariable logistic regression adjusting for demographics and used a backward selection technique to identify a set of diagnoses or a set of procedures that may be a driver for this changing risk in dialysis-requiring AKI.
  
  
  RESULTS
  From 2007 to 2009, the population incidence of dialysis-requiring AKI increased by 11% per year (95% confidence interval, 1.07 to 1.16; P<0.001). Using backward selection, we found that the temporal trend in the six diagnoses, septicemia, hypertension, respiratory failure, coagulation/hemorrhagic disorders, shock, and liver disease, sufficiently and fully accounted for the temporal trend in dialysis-requiring AKI. In contrast, temporal trends in 15 procedures most commonly associated with dialysis-requiring AKI did not account for the increasing dialysis-requiring AKI trend.
  
  
  CONCLUSIONS
  The increasing risk of dialysis-requiring AKI among hospitalized patients in the United States was highly associated with the changing burden of six acute and chronic conditions but not with surgeries and procedures.
authors.affiliation: Departments of Medicine, Division of Nephrology, raymond.hsu@ucsf.edu.
authors.forename: Raymond K
authors.initials: RK
authors.lastname: Hsu
authors.affiliation: Epidemiology and Biostatistics, and.
authors.forename: Charles E
authors.initials: CE
authors.lastname: McCulloch
authors.affiliation: Department of Medicine, Division of Nephrology, University of Michigan, Ann Arbor, Michigan;
authors.forename: Michael
authors.initials: M
authors.lastname: Heung
authors.affiliation: Department of Medicine, Division of Nephrology, University of Michigan, Ann Arbor, Michigan;
authors.forename: Rajiv
authors.initials: R
authors.lastname: Saran
authors.affiliation: Department of Medicine, Division of Nephrology, University of Michigan, Ann Arbor, Michigan;
authors.forename: Vahakn B
authors.initials: VB
authors.lastname: Shahinian
authors.affiliation: Division of Diabetes Translation, Centers for Disease and Control and Prevention, Atlanta, Georgia;
authors.forename: Meda E
authors.initials: ME
authors.lastname: Pavkov
authors.affiliation: Division of Diabetes Translation, Centers for Disease and Control and Prevention, Atlanta, Georgia;
authors.forename: Nilka Ríos
authors.initials: NR
authors.lastname: Burrows
authors.affiliation: Medicine, University of California, San Francisco, San Francisco, California; Department of Medicine, San Francisco General Hospital, San Francisco, California.
authors.forename: Neil R
authors.initials: NR
authors.lastname: Powe
authors.affiliation: Departments of Medicine, Division of Nephrology.
authors.forename: Chi-yuan
authors.initials: CY
authors.lastname: Hsu
mesh_terms: D058186:Acute Kidney Injury / Q000453:epidemiology / Q000209:etiology* / Q000628:therapy; D015331:Cohort Studies; D005260:Female; D006760:Hospitalization; D006801:Humans; D007676:Kidney Failure, Chronic / Q000628:therapy; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D006435:Renal Dialysis; D012189:Retrospective Studies; D012306:Risk; D014481:United States / Q000453:epidemiology
keywords: acute kidney injury; cohort studies; dialysis; epidemiology; humans; incidence; renal dialysis; retrospective studies; sepsis; temporal trend