Pre-morbid glycemic control modifies the interaction between acute hypoglycemia and mortality

Area of Science:

• Critical Care Medicine
• Endocrinology
• Hospital Medicine

Background:

• Glycemic control is crucial in intensive care unit (ICU) patients.
• Pre-morbid glycemic status may influence outcomes in critically ill individuals.
• The interplay between pre-existing hyperglycemia and acute hypoglycemia in the ICU requires further investigation.

Purpose of the Study:

• To investigate how pre-morbid glycemic control affects the association between acute hypoglycemia and in-hospital mortality.
• To analyze the impact of varying levels of pre-admission glycated hemoglobin (HbA1c) on hypoglycemia incidence and outcomes.
• To determine if chronic hyperglycemia modifies the risk posed by acute hypoglycemic episodes in the ICU.

Main Methods:

• A retrospective observational study involving 3084 critically ill patients with pre-ICU HbA1c data.
• Patients were stratified into three cohorts based on pre-admission HbA1c: <6.5%, 6.5-7.9%, and ≥8.0%.
• Logistic regression analysis was used to assess the relationship between hypoglycemia (moderate: 40-69 mg/dL, severe: <40 mg/dL) and mortality, considering pre-morbid glycemic control.

Main Results:

• Hypoglycemia incidence (moderate and severe) significantly increased with higher pre-admission HbA1c levels (p < 0.001).
• Pre-morbid glycemic control significantly modified the association between hypoglycemia and mortality (interaction p = 0.009).
• Patients with severe hypoglycemia and HbA1c ≥8.0% had a substantially elevated mortality risk (OR 23.46, 95% CI 5.13-107.28).

Conclusions:

• Chronic hyperglycemia before ICU admission elevates hypoglycemia risk.
• Pre-morbid hyperglycemia intensifies the adverse association between acute hypoglycemia and mortality in critically ill patients.
• Optimizing glycemic control prior to critical illness may mitigate risks associated with hypoglycemia in the ICU.