Evaluating the Role of Cystatin C and Creatinine as Markers of Renal Recovery in Critically Ill Patients After Acute Kidney Injury.
Condition: Acute Kidney Injury; Chronic Kidney Disease; Acute Kidney Disease
MeSH terms: Kidney Diseases; Renal Insufficiency, Chronic; Acute Kidney Injury; Wounds and Injuries
Study type: Observational [Patient Registry]

Summary: 
      This is a cohort study in which patients who survive Acute Kidney Injury (AKI) during
      intensive care unit (ICU) admission are recalled at 3-6 months and renal function tests are
      performed.

      The purpose of the study is describe renal function in AKI survivors at follow-up.

      Additional aims are to determine how well admission values of renal function markers perform
      as predictors of renal function at follow-up and whether estimates of renal function at
      follow-up differ depending on which renal function marker is used.
    

Detailed description: 
      Type of study: Cohort study with prospectively collected clinical data cross-matched with
      local & national databases.

      Source population: Patients suffering from AKI on a mixed intensive care unit, at the
      Karolinska University Hospital, Solna.

      Setting: Single centre, Central Intensive Care unit Karolinska University hospital, Solna,
      Stockholm from September 2008 and May 2011.

      Exposure: AKI on ICU and grade of AKI according to the RIFLE criteria Intervention: none

      Outcome: Renal function 3 months after ICU discharge according to creatinine and Cystatin C
      measurements.

      Parameters: Co-morbidities, ICU diagnoses, disease severity score, daily physiological and
      laboratory parameters, medications administered, interventions RRT (Renal replacement
      therapy), mechanical intervention, inotropes, surgery.

      Data is crossmatched with national registries including the Swedish cause of death register
      (to obtain dates of death), the Swedish renal register (to obtain details of patients
      receiving chronic dialysis and with pre-existing Chronic Kidney Disease (CKD) diagnoses. Data
      is also cross matched with a large local ICU register (Clinisoft) to obtain physiological
      parameters& intervention details. Clinisoft is also used to obtain risk of death for all ICU
      patients and all AKI patients (from the source population). Ethical approval has been granted
      by Stockholm Regional ethical review body (2008-408-32 2008/443-31/1-3, 2010/1780-31-2,
      2011-408-32 and 2016-1801-32).

      Aims:

        1. Describe the incidence of renal dysfunction in terms of Glomerular filtration rate (GFR)
           under 60ml/min/173m² at 3-6 months follow-up after AKI. According to serum Cystatin C
           and Creatinine values.

        2. Describe the incidence of Acute Kidney Disease (AKD) at 3 month follow-up.

        3. Produce a predictive model using comorbidities and admission data to CKD (Chronic Kidney
           Disease) and AKD 3-6 after AKI in intensive care patients.

        4. Examine how estimated GFR using creatinine and Cystatin C differ from measured Iohexol
           GFR at 6 month follow-up.
    

Intervention name(s): No intervention
Intervention type(s): Other
Observational model: Cohort
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        Patients admitted to the central intensive care unit at Karolinska University hospital, who
        suffered from AKI during the period September 2008 until May 2011.
      
Keywords: Cystatin C; Creatinine; Glomerular Filtration Rate