Alhakak A, Butt JH, Gerds TA, et al. - Using data from Danish nationwide registries, the risk of adverse outcomes was examined across the spectrum of glycated hemoglobin (HbA1c) levels among hospitalized COVID-19 patients with and without diabetes.

• A composite of COVID-19 severe acute respiratory syndrome (ie, severe COVID-19 infection [ICD-10 code: B972A]), ICU admission (NCSP codes: NABE, NABB, BGDA), or all-cause mortality was assessed as the primary study outcome.

• All-cause mortality was assessed as the secondary study outcome.

• A total of 3,295 hospitalized COVID-19 patients with an available HbA1c (56.2% male, median age 73.9 years) were identified; 35.8% of these had diabetes.

• A higher associated risk of the composite outcome was observed among patients with COVID-19 and HbA1c < 48 mmol/mol or HbA1c > 64 mmol/mol.

• Similarly, varying HbA1c levels were linked with higher risk of the composite outcome among patients without diabetes.

• Among patients without diabetes, there was greater standardized absolute risk difference of the composite outcome with HbA1c < 31 mmol/mol and HbA1c 42 to 47 mmol/mol, when compared with HbA1c 31 to 36 mmol/mol (reference).