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<h5 class="section-title" id="d13202487e541">Question</h5>
<p id="d13202487e543">Can the risk of progression to advanced chronic kidney disease
be accurately predicted
when patients who had acute kidney injury during their hospital stay are discharged
from the hospital?
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<h5 class="section-title" id="d13202487e546">Findings</h5>
<p id="d13202487e548">A multivariable model was developed with 9973 participants and
was externally validated
with 2761 participants. In the external validation cohort, a model that included age,
sex, acute kidney injury stage, prehospitalization serum creatinine level, albuminuria,
and discharge serum creatinine achieved a C statistic of 0.81 for predicting advanced
chronic kidney disease after hospital discharge.
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<h5 class="section-title" id="d13202487e551">Meaning</h5>
<p id="d13202487e553">This model was able to predict advanced chronic kidney disease
following hospitalization
with acute kidney injury but requires evaluation of its utility in a clinical setting.
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<h5 class="section-title" id="d13202487e557">Importance</h5>
<p id="d13202487e559">Some patients will develop chronic kidney disease after a hospitalization
with acute
kidney injury; however, no risk-prediction tools have been developed to identify high-risk
patients requiring follow-up.
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<h5 class="section-title" id="d13202487e562">Objective</h5>
<p id="d13202487e564">To derive and validate predictive models for progression of
acute kidney injury to
advanced chronic kidney disease.
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<h5 class="section-title" id="d13202487e567">Design, Setting, and Participants</h5>
<p id="d13202487e569">Data from 2 population-based cohorts of patients with a prehospitalization
estimated
glomerular filtration rate (eGFR) of more than 45 mL/min/1.73 m
<sup>2</sup> and who had survived hospitalization with acute kidney injury (defined
by a serum
creatinine increase during hospitalization > 0.3 mg/dL or > 50% of their prehospitalization
baseline), were used to derive and validate multivariable prediction models. The risk
models were derived from 9973 patients hospitalized in Alberta, Canada (April 2004-March
2014, with follow-up to March 2015). The risk models were externally validated with
data from a cohort of 2761 patients hospitalized in Ontario, Canada (June 2004-March
2012, with follow-up to March 2013).
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<h5 class="section-title" id="d13202487e575">Exposures</h5>
<p id="d13202487e577">Demographic, laboratory, and comorbidity variables measured
prior to discharge.</p>
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<h5 class="section-title" id="d13202487e580">Main Outcomes and Measures</h5>
<p id="d13202487e582">Advanced chronic kidney disease was defined by a sustained reduction
in eGFR less
than 30 mL/min/1.73 m
<sup>2</sup> for at least 3 months during the year after discharge. All participants
were followed
up for up to 1 year.
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<h5 class="section-title" id="d13202487e588">Results</h5>
<p id="d13202487e590">The participants (mean [SD] age, 66 [15] years in the derivation
and internal validation
cohorts and 69 [11] years in the external validation cohort; 40%-43% women per cohort)
had a mean (SD) baseline serum creatinine level of 1.0 (0.2) mg/dL and more than 20%
had stage 2 or 3 acute kidney injury. Advanced chronic kidney disease developed in
408 (2.7%) of 9973 patients in the derivation cohort and 62 (2.2%) of 2761 patients
in the external validation cohort. In the derivation cohort, 6 variables were independently
associated with the outcome: older age, female sex, higher baseline serum creatinine
value, albuminuria, greater severity of acute kidney injury, and higher serum creatinine
value at discharge. In the external validation cohort, a multivariable model including
these 6 variables had a C statistic of 0.81 (95% CI, 0.75-0.86) and improved discrimination
and reclassification compared with reduced models that included age, sex, and discharge
serum creatinine value alone (integrated discrimination improvement, 2.6%; 95% CI,
1.1%-4.0%; categorical net reclassification index, 13.5%; 95% CI, 1.9%-25.1%) or included
age, sex, and acute kidney injury stage alone (integrated discrimination improvement,
8.0%; 95% CI, 5.1%-11.0%; categorical net reclassification index, 79.9%; 95% CI, 60.9%-98.9%).
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<h5 class="section-title" id="d13202487e593">Conclusions and Relevance</h5>
<p id="d13202487e595">A multivariable model using routine laboratory data was able
to predict advanced chronic
kidney disease following hospitalization with acute kidney injury. The utility of
this model in clinical care requires further research.
</p>
</div><p class="first" id="d13202487e599">This study uses data from Canadian administrative
and clinical ambulatory databases
to derive and validate risk prediction models for advanced chronic kidney disease
in patients hosptialized with acute kidney injury.
</p>