The Potential Diagnostic and Predictive Role of HbA1c in Diabetic, Septic Patients: A Retrospective Single-Center Study

Background. As diabetes mellitus is a major risk factor of sepsis, we aimed to evaluate the possible effects of diabetes mellitus and poor glycemic control on the diagnosis of sepsis. Methods. In our retrospective study, we included diabetic, septic patients—in whom the diagnosis of sepsis was based on the systemic inflammatory response syndrome (SIRS) criteria (n = 112, SIRS group)—who had HbA1c levels measured either in the previous 30 days (n = 39, SIRS 30 d subgroup) or within 24 hours after their emergency department admission (n = 73, SIRS 24 h subgroup). We later selected those patients from the SIRS group, whose sequential organ failure assessment (SOFA) score was ≥2 (n = 55, SOFA group), and these patients were also divided based on the time of HbA1c measurement (n = 21, SOFA 30 d subgroup and n = 34, SOFA 24 h subgroup). We analyzed the relationship between laboratory parameters, length of hospital stay, and HbA1c. Results. We found a significant positive correlation between glucose and HbA1c ( p < 0.001 , p < 0.001 , respectively), significant negative correlations between white blood cell count (WBC) and glucose ( p = 0.01 , p = 0.02 , respectively), WBC and HbA1c levels ( p = 0.001 , p = 0.02 , respectively) in the SIRS 24 h and SOFA 24 h subgroups. Furthermore, there was a significant positive correlation between length of hospital stay and HbA1c in the SOFA 24 h subgroup ( p = 0.01 ). No significant correlations were found in the SIRS 30 d and SOFA 30 d subgroups. Conclusion. Based on our results, normal WBC with elevated HbA1c might be considered a positive SIRS criterium in diabetic, SIRS 24 h patients. Besides this potential diagnostic role, HbA1c might also be an additional prognostic biomarker in diabetic, SOFA 24 h patients.