The Relationship Between Acute and Chronic Hyperglycemia and Outcomes in Burn Injury

Abstract

A significant proportion of patients with burn injury have diabetes. Although hyperglycemia during critical illness has been associated with poor outcomes, patients with chronic hyperglycemia based on elevated hemoglobin A1c (HbA1c) measurements at admission have been shown to tolerate higher glucose levels during hospitalization. This relationship has not been evaluated in the burn population. The objective of this study was to examine the impact of chronic glucose control on outcomes in the acute period after burn. This is a retrospective analysis comparing outcomes in patients with chronic hyperglycemia (HbA1c ≥ 6.5%) and euglycemia (HbA1c <6.5%). Patients aged 18 to 89 years, admitted for initial burn care between January 1, 2009, and June 30, 2010, with an HbA1c measurement at admission were included. The primary endpoint was unplanned readmissions, with secondary endpoints of length of stay and mortality. We included 258 patients (32 with chronic hyperglycemia and 226 with euglycemia). Burn severity was similar between the groups. Patients with chronic hyperglycemia were significantly older and were more likely to have diabetes, respiratory disease, and hypertension. Chronic hyperglycemia was associated with significantly higher time-weighted glucose and glucose variability. Survival rates were similar, but the chronic hyperglycemia group had a significantly longer length of stay (13 vs 9 days; P = .038) and a higher rate of unplanned readmission (18.8 vs 3.6%; P = .001). Chronic hyperglycemia before burn injury is associated with altered glycemic response after burn injury and worse outcomes. Further research is needed to identify whether chronic hyperglycemia necessitates a modified approach to burn care or glycemic management.