Objectives. To evaluate the predictive value of HbA1c levels in medical patients admitted to the emergency department (ED) regarding in-hospital-mortality, length of stay (LOS) and transferral to intensive care unit (ICU) and to compare them with different physiologically based emergency scoring systems and the Manchester Triage System (MTS).
Methods. In a prospective cohort-study, 1117 consecutive patients presenting to the medical ED were assessed. Data collected included age, sex, vital signs, temperature, oxygen saturation, respiratory rate, AVPU (Alert; Verbal response; response to Pain; Unresponsive)-score, MTS, different emergency scores and HbA1c. The data were correlated with LOS, hospital mortality and intensive care utilisation.
Results. HbA1c had similar accuracy in predicting LOS as most physiologically based scores (AUC=0.568, p=0.688 to 0.714) and ICU utilisation (AUC=0.525, p=0.001 compared with MTS, for all others p=0.077 to 0.830). HbA1c was positively correlated with LOS and ICU-transferral but correlated poorly with mortality, resulting in low predictive power (AUC=0.501, p=0.033 to 0.845). The subgroups with HbA1c below the median and below 6.5% had a shorter LOS (p=0.012 and p=0.004).
The differences for other subgroups were not significant.
Conclusions. HbA1c was positively correlated with LOS and ICU-referral, reflecting higher health-care utilisation, indicating that it may be a useful parameter in evaluating severity of illness in emergency patients.
Key Words: Glycated haemoglobin, Emergency score, Manchester Triage System, mortality, length of stay, ICU referral