# Improving acute kidney injury alerts in tertiary care by linking primary care data: An observational cohort using routine care data

## TL;DR

Linking primary and tertiary care data improves diagnosing acute kidney injury in emergency settings, especially for older patients and women.

## Contribution

This study demonstrates that integrating primary care data with tertiary care data enhances AKI detection accuracy and enables earlier diagnosis.

## Key findings

- Linking primary and tertiary care data identified AKI in 7886 additional emergency department visits.
- AKI was diagnosed 2.8 days earlier on average when primary care data was included.
- The added value was highest for women and patients aged 60 years or older.

## Abstract

Acute kidney injury (AKI) is easily missed and underdiagnosed in routine clinical care. Timely AKI management is important to decrease morbidity and mortality risks. We recently implemented an AKI e-alert at the University Medical Center Utrecht, comparing plasma creatinine concentrations with historical creatinine baselines, thereby identifying patients with AKI. This alert is limited to data from tertiary care, and primary care data can increase diagnostic accuracy for AKI. We assessed the added value of linking primary care data to tertiary care data, in terms of timely diagnosis or excluding AKI.

With plasma creatinine tests for 84,984 emergency department (ED) visits, we applied the Kidney Disease Improving Global Outcome guidelines in both tertiary care-only data and linked data and compared AKI cases.

Using linked data, the presence of AKI could be evaluated in an additional 7886 ED visits. Sex- and age-stratified analyses identified the largest added value for women (an increase of 4095 possible diagnoses) and patients ≥60 years (an increase of 5190 possible diagnoses). We observed 398 additional visits where AKI was diagnosed, as well as 185 cases where AKI could be excluded. We observed no overall decrease in time between baseline and AKI diagnosis (28.4 days vs. 28.0 days). For cases where AKI was diagnosed in both data sets, we observed a decrease of 2.8 days after linkage, indicating a timelier diagnosis of AKI.

Combining primary and tertiary care data improves AKI diagnostic accuracy in routine clinical care and enables timelier AKI diagnosis.