Worse long-term control of blood sugar increases risks in diabetic trauma patients

Reviewed by Kate Anderton, B.Sc. (Editor)Dec 18 2019

In trauma patients with diabetes, poorer long-term control of blood glucose levels is linked to a higher risk of death and trauma-related complications, reports a study in SHOCK®: Injury, Inflammation, and Sepsis: Laboratory and Clinical Approaches, Official Journal of the Shock Society. The journal is published in the Lippincott portfolio by Wolters Kluwer.

"Trauma patients with worse long-term glycemic [blood glucose] control had increased risks of developing pneumonia, renal failure, urinary tract infection and death," according to the new research by Jan O. Jansen, MBBS, PhD, Associate Professor of Surgery, and colleagues of University of Alabama at Birmingham (UAB) Trauma Center. They believe assessing diabetes control might help in assessing the risk of adverse outcomes for the many diabetic patients seen at US trauma centers.

Higher HbA1c Levels Lead to Higher Risks in Trauma Patients

The study included approximately 26,000 patients hospitalized at the authors' trauma center between 2011 and 2018. All had available data on the glycated hemoglobin, or HbA1c – the main indicator of long-term blood glucose levels and diabetes control.

Based on HbA1c levels, about 69 percent of patients were classified as nondiabetic or having "excellent" blood glucose control. Another 23 percent of patients had "good" glucose control, while 4.6 had "moderate" and 3.5 percent had "poor" control. Rates of death and major trauma-related complications for patients in the different blood glucose control groups.

Patients without diabetes or with excellent blood glucose control were younger than the other groups. After adjustment for age and injury characteristics, the nondiabetic/excellent control group spent fewer days in the hospital, in the intensive care unit, and on mechanical ventilation, compared to those with good, moderate, or poor blood glucose control.

Several other risks were higher in the groups with higher HbA1c levels, and some of these risks increased as diabetes control decreased. For example, the relative risk of pneumonia was 25 percent higher for patients with good glucose control, climbing to over 50 percent higher for those with poor glucose control.

There was a similar pattern for acute kidney injury (sudden decline in kidney function) – risk was more than three times higher for patients with poor glucose control. All patients with less-than-excellent glucose control were at higher risk of urinary tract infections. Patients with lower diabetes control also tended to have a higher rate of sepsis, although this difference wasn't statistically significant.

Patients with worse glycemic control also had an increased mortality risk. Compared to patients with excellent diabetes control, the relative risk of death was 33 percent higher for the group with good control and about 50 percent for the moderate and poor control groups. (For perspective, the absolute risk of death was 2.6 to 5.0 percentage points higher in the groups with less than "excellent" diabetes control.)

Some associations varied by age: the increased risk of pneumonia was significant only for patients aged 60 or older, while the risks of acute kidney injury and urinary tract infections appeared mainly in younger patients.

Both diabetes and trauma are common in the United States – previous studies have estimated that seven to nine percent of patients admitted to US trauma centers may have a diagnosis of diabetes. While acute (short-term) increases in blood sugar are associated with increased risks in trauma patients, less is known about the effects of long-term diabetes control.

The new study provides evidence that worse long-term control of blood sugar – as indicated by higher HbA1c – is related to increased risks of adverse outcomes in diabetic trauma patients. Dr. Jansen and colleagues conclude: "Routine checking of HbA1c levels as part of admission blood work may be worth considering, particularly since undiagnosed diabetes is common, in the population as a whole, and in trauma patients specifically."