Effect of Baseline HbA1c and Inpatient Glycemic Control on Mortality and Organ Dysfunction among Patients with Diabetes Mellitus Hospitalized for COVID-19: A Multicenter Retrospective Cohort Study.

BACKGROUND

Individuals with diabetes mellitus (DM) show increased susceptibility to COVID-19 infection with higher risk for severe disease and mortality.

OBJECTIVES

We investigated whether glycemic-related factors may affect the outcomes of patients with DM hospitalized due to COVID-19.

METHODOLOGY: This is a multicenter retrospective cohort study under the initiative of the Philippine College of Endocrinology, Diabetes, and Metabolism involving eight training hospitals in the Philippines from January 2021 to January 2022. Patients with DM hospitalized due to COVID-19 were included. Univariable and multivariable analyses were done to determine whether baseline glycemic control based on glycosylated hemoglobin (HbA1c) and inpatient glycemic control based on capillary blood glucose are associated with composite poor clinical outcome of mortality and end-organ dysfunction.

RESULTS

Among 1,093 patients, 54% had HbA1c >7%. Critical COVID-19 disease was greater in patients with poor baseline glycemic control (28.43% vs 19.72%, p = 0.001) and poor inpatient glycemic control (25.7% vs 12.64%, p <0.001). Both poor baseline glycemic (AOR 1.41, p = 0.017) and poor inpatient glycemic control (AOR 2.6, p <0.001) were associated with composite poor clinical outcome of mortality and end-organ dysfunction after adjusting for each other, but lost significance after adjusting for age, COVID-19 severity, and presence of comorbidities. COVID-19 severity had the greatest association with composite poor clinical outcome after adjusting for all other variables. HbA1c >7% increased the odds of poor inpatient control (OR = 3.10, 95% CI: 2.32-4.17, p <0.001), even after adjusting for steroid use.

CONCLUSION

COVID-19 severity had the greatest impact and is the only variable with a statistically significant association with composite poor clinical outcomes after adjusting for all other variables. Poor glycemic control on admission and during hospitalization were associated with more severe COVID-19, although they did not directly impact clinical outcomes. Measures to optimize glycemic control both in the long term and during hospitalization should be considered to prevent severe COVID-19, hence improving clinical outcomes and survival.