The purpose of this study is to investigate the clinical outcomes and glucose control metrics of critically ill patients with previously undiagnosed diabetes compared to those with known diabetes at the time of admission to the intensive care unit (ICU).

This case control study compares previously undiagnosed diabetic patients (defined as HbA1c > 6.5% and no history of diabetes), to those with known diabetes, using 1:1 matching. Patients met inclusion criteria by having HbA1c available on ICU admission and at least four blood glucose tests during their ICU stay. Primary outcomes included ICU length of stay and inpatient mortality. Secondary outcomes included glucose metrics: mean blood glucose, coefficient of variation and percentage of patients who developed hypoglycemia.

Inclusion Criteria:20

• Patients admitted between 9/14/2011 and 11/30/19 with HbA1c available on admission and at least four documented blood glucose tests during their ICU stay.

Exclusion Criteria:

• Patients admitted for diabetic ketoacidosis.
• Patients admitted to the ICU following cardiovascular surgery.

Patients admitted to the ICU where they were subsequently diagnosed for the first time with diabetes.