M. Rajaei1, P. Bosarge1, R. Griffin2, G. McGwin2, J. Jansen1, J. Kerby1 1UAB,Division Of Acute Care Surgery, Department Of Surgery, School Of Medicine,Birmingham, ALABAMA, USA 2UAB,Department Of Epidemiology, School Of Public Health,Birmingham, ALABAMA, USA 3UAB,Division Of Acute Care Surgery, Department Of Surgery, School Of Medicine,Birmingham, ALABAMA, USA 4UAB,Department Of Epidemiology, School Of Public Health,Birmingham, ALABAMA, USA
Introduction: Previous studies have identified hyperglycemia as an independent risk factor for poor outcomes in patients following traumatic injury. However, they have utilized serum glucose of ≥200 mg/dl to define the study population. The purpose of this study was to evaluate the effects of elevated admission glycosylated hemoglobin (HbA1C) on morbidity and mortality of trauma patients.
Methods: HbA1C on admission was obtained on all trauma patients presenting to an academic trauma service between January 2013 and June 2017. A HbA1C < 6.5 is defined by the American Diabetes Association as a more stringent A1C goal. Therefore, a HbA1C ≥ 6.5 was used to define our study population. A Cox proportional hazards model assuming equal time at risk and adjusted for age, sex, Injury Severity Score (ISS) and injury mechanism was used to estimate risk ratios (RRs) and associated 95% confidence intervals (CIs) for the association between HbA1C and specific outcomes of interest.
Results: Total of 10,586 patients were admitted to the trauma service during the period of study. Of these, 9,230 patients had admission HbA1C available and were included in the study. A total of 871 patients had a HbA1C ≥6.5 at admission. These patients were more likely to be Caucasian (74% vs. 66%, p<0.001) and were older (mean 59 vs. 42 years, p<0.001) compared to those with normal HbA1C. Individuals with HbA1C ≥6.5 had a longer hospital length of stay (mean 12 vs. 9 days, p<0.0001), ICU days (mean 13 vs. 10, p<0.001), and required longer ventilator assistance (mean 13 vs. 10, p=0.001). Despite having less severe injuries, patients with HbA1C ≥6.5 had a 43% increased risk of developing pneumonia (RR 1.43, 95% CI 1.09-1.88), a 46% increased risk of death (RR 1.46, 95% CI 1.14-1.87), and a 2.2 fold increased risk of renal failure(RR 2.25, 95% CI 1.58-3.19).
Conclusion: Trauma patients with less than stringent glycemic control on admission are at increased risk of morbidity and mortality. These results can help identify patients at increased risk on admission following traumatic injury and help inform future trials evaluating glycemic control in trauma.
