Association of Inpatient Glucose Measurements With Amputations in Patients Hospitalized With Acute Diabetic Foot

Context: The association of inpatient glucose measurements with amputations in patients admitted with acute diabetic foot has not been described.

Objective: To evaluate the relationship of hyperglycemia, hypoglycemia, and glucose variability during hospitalization with amputations in patients hospitalized with acute diabetic foot.

Design: Retrospective cohort study.

Setting: Academic tertiary hospital.

Patients: We reviewed demographic, clinical, laboratory, and point-of-care glucose data in patients hospitalized with acute diabetic foot in the Diabetic Foot Unit during 2015 through 2017.

Main outcome measures: The primary outcomes were any or major amputations during hospitalization. Secondary outcomes included length of hospitalization and in-hospital mortality.

Results: During the study period, 418 patients were hospitalized in the Diabetic Foot Unit and 45,496 glucose measurements were taken. Patients experiencing any hyperglycemia and any or severe hypoglycemia were more likely to undergo any or major amputations during hospitalization. High glycemic variability was associated with major amputations. Peripheral vascular disease (PVD), high Wagner score, and hypoglycemia were independent predictors of amputations. Older age, PVD, previous amputation, elevated white blood cell level, high Wagner score, and hypoglycemia were independent predictors of major amputations.

Conclusions: In-patient hypoglycemia emerged as an independent risk factor for any and major amputations. Although it is unclear whether hypoglycemia directly contributes to adverse outcomes or is simply a biomarker of disease severity, efforts to minimize in-hospital hypoglycemic events are warranted.