title: Do acute elevations of serum creatinine in primary care engender an increased mortality risk?
abstract: BACKGROUND
  The significant impact Acute Kidney Injury (AKI) has on patient morbidity and mortality emphasizes the need for early recognition and effective treatment. AKI presenting to or occurring during hospitalisation has been widely studied but little is known about the incidence and outcomes of patients experiencing acute elevations in serum creatinine in the primary care setting where people are not subsequently admitted to hospital. The aim of this study was to define this incidence and explore its impact on mortality.
  
  
  METHODS
  The study cohort was identified by using hospital data bases over a six month period.
  
  
  METHODS
  People with a serum creatinine request during the study period, 18 or over and not on renal replacement therapy.The patients were stratified by a rise in serum creatinine corresponding to the Acute Kidney Injury Network (AKIN) criteria for comparison purposes. Descriptive and survival data were then analysed.Ethical approval was granted from National Research Ethics Service (NRES) Committee South East Coast and from the National Information Governance Board.
  
  
  RESULTS
  The total study population was 61,432. 57,300 subjects with 'no AKI', mean age 64.The number (mean age) of acute serum creatinine rises overall were, 'AKI 1' 3,798 (72), 'AKI 2' 232 (73), and 'AKI 3' 102 (68) which equates to an overall incidence of 14,192 pmp/year (adult). Unadjusted 30 day survival was 99.9% in subjects with 'no AKI', compared to 98.6%, 90.1% and 82.3% in those with 'AKI 1', 'AKI 2' and 'AKI 3' respectively. After multivariable analysis adjusting for age, gender, baseline kidney function and co-morbidity the odds ratio of 30 day mortality was 5.3 (95% CI 3.6, 7.7), 36.8 (95% CI 21.6, 62.7) and 123 (95% CI 64.8, 235) respectively, compared to those without acute serum creatinine rises as defined.
  
  
  CONCLUSIONS
  People who develop acute elevations of serum creatinine in primary care without being admitted to hospital have significantly worse outcomes than those with stable kidney function.
authors.forename: Helen
authors.initials: H
authors.lastname: Hobbs
authors.forename: Paul
authors.initials: P
authors.lastname: Bassett
authors.forename: Toby
authors.initials: T
authors.lastname: Wheeler
authors.forename: Michael
authors.initials: M
authors.lastname: Bedford
authors.forename: Jean
authors.initials: J
authors.lastname: Irving
authors.forename: Paul E
authors.initials: PE
authors.lastname: Stevens
authors.affiliation: East Kent University Hospitals NHS Foundation Trust, Kidney Kent Research Group, Kent Kidney Care Centre, Kent and Canterbury Hospital, Ethelbert Road, Canterbury, Kent CT1 3NG, England. Chris.Farmer1@nhs.net.
authors.forename: Christopher K T
authors.initials: CK
authors.lastname: Farmer
mesh_terms: D058186:Acute Kidney Injury / Q000097:blood* / Q000401:mortality*; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D015897:Comorbidity; D003404:Creatinine / Q000097:blood*; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D011320:Primary Health Care; D011379:Prognosis; D012737:Sex Factors; D013997:Time Factors
chemical_list: D003404:Creatinine