BACKGROUND
Emergency department (ED) routine data represent a unique opportunity for syndromic surveillance for both communicable and non-communicable diseases. In 2020 the Robert Koch Institute (RKI) established a syndromic surveillance system, using ED data from the AKTIN registry.
OBJECTIVE
In this context, this study aims to develop and validate syndrome definitions for acute coronary syndrome (ACS), myocardial infarction (MI), and stroke (STR).
METHODS
First, syndrome definitions including ED diagnosis, chief complaints, diagnostic certainty and disposition were developed with clinical experts. Then, using the retrospective routine ED data provided by the AKTIN registry, we conducted internal validation by linking ED cases fulfilling the syndrome definition criteria with hospital discharge diagnoses and calculating sensitivity, specificity, and accuracy. Lastly, external validation comprised the comparison of the ED cases fulfilling the syndrome definition criteria with the German hospital diagnosis statistic.
RESULTS
We analyzed data from nine EDs, totaling 704,797 attendances from January 1, 2019, to March 5, 2021. Syndrome definitions were based on ICD-10 diagnoses, chief complaints, and disposition information. The internal validation showed high levels of accuracy for the syndrome definitions. For ACS, the sensitivity was 85.3%, specificity 96.3 %, and accuracy 95.9 %. For MI, sensitivity was 56.6 %, specificity 99.6 %, and accuracy 99.0 %. Sensitivity for STR was 80.5 %, specificity 97.5 %, and accuracy 96.7 %. The external validation showed high levels of correspondence between the ED data and the German hospital statistics, particularly in older age groups. Differences in younger age groups, especially in the detection of MI in younger women were noted.
CONCLUSIONS
Our syndrome definitions showed high levels of internal and external validity. The integration of these indicators into the ED syndromic surveillance system could enhance timely public health surveillance in Germany.