Acute kidney injury in patients presenting with chest pain to the emergency department, a descriptive study of the most common discharge diagnoses and mortality.

OBJECTIVE

To describe patients presenting with chest pain to the emergency department (ED) according to acute kidney injury (AKI) status at arrival, with a focus on the most common discharge diagnoses and on long-term mortality.

METHODS

All adult patients visiting the Karolinska University Hospital ED between December 2010 and October 2014 with a principal complaint of chest pain were included. AKI at arrival was defined as an increase in presentation serum creatinine concentration of at least 26 µmol/l ( ≥ 0.3 mg/dl) or at least 50% above baseline. Risk ratios (RR) with 95% confidence intervals (CIs) between the AKI and no-AKI groups were calculated for the most common discharge diagnoses in the AKI group. Hazard ratios for long-term mortality were calculated using Cox regression models with adjustment for covariates.

RESULTS

In total, 8480 patients were included, of whom 476 (5.6%) had AKI. AKI patients were older and had more comorbidities. It was more common in AKI patients compared to no AKI patients to be diagnosed with heart failure, RR 3.03 (CI: 2.15-4.26) and myocardial infarction RR 1.44 (CI: 1.01-2.04). During a median follow-up of 3.2 years (interquartile range: 2.1-4.3), 37% of the patients with AKI died compared with 16% of patients without AKI. The multivariable adjusted hazard ratio of death for AKI compared with no AKI was 1.30 (95% CI: 1.10-1.53).

CONCLUSION

When attending the ED, patients with chest pain and AKI were more likely to be diagnosed with heart failure and myocardial infarction and had an increased long-term mortality compared with patients with no AKI.