Blood Sugar matters in COVID outcomes even without a history of diabetes

June 26, 2020

Blood Sugar matters in COVID outcomes even without a history of diabetes.

Elevation of blood glucose level predicts worse outcomes in hospitalized patients with COVID-19: a retrospective cohort study 

Peer Reviewed and Published in BMJ Open Diabetes Research and Care - Retrospective Review

Data from consecutive inpatients with COVID-19 from Wuhan Hankou Hospital and No. Six Hospital of Wuhan between 26 December 2019 and 15 March 2020 were collected in this study (n=2289). The final follow-up date was 19 March 2020 (**although not specifically stated, this would mean that not all patients had a conclusion of their disease by the final follow up date which would impact outcomes).  The primary purpose was to explore the effect of blood glucose on the outcomes of critical disease and mortality.  Any patient, regardless of prior diabetes status, who had an elevated admission glucose was included.

Cox proportional hazard regression models were applied to evaluate the association between the multiple blood glucose indexes and prognosis. Sensitivity analysis was conducted to evaluate the association of admission blood glucose level with the risk of critical cases/death among non-critical patients without diabetes hospital admission and critical care admission.

Conclusions:  This study found that blood glucose level was an independent risk factor to predict the progression to critical cases/death in non-critical cases and in-hospital mortality in critical cases, whereas patients with higher median glucose level during hospital stay or after critical diagnosis had significantly poorer clinical outcomes

Newly diagnosed diabetes is associated with a higher risk of mortality than known diabetes in hospitalized patients with COVID ‐19

Peer Reviewed and Published in Diabetes, Obesity and Metabolism

This study included 453 adult patients who were hospitalized with laboratory + COVID-19 at Wuhan Union hospital between January 22, 2020 and March 17, 2020.

Patients were classified into four categories based on the first laboratory measurement and a history of diabetes after hospital admission: normal glucose, hyperglycemia (fasting glucose 5.6-6.9 mmol/L and/or HbA1c 5.7-6.4%),  newly diagnosed diabetes (fasting glucose > 7mmol/L or HbA1c > 6.5%, and diabetes. The main composite endpoints were invasive mechanical ventilation (IMV), admission to the intensive care unit (ICU), or death.  All patients had a final outcome of their disease (this is an important factor in interpreting results). 

Pearson’schi-square or the Fisher’s exact test for categorical variables and the General Linear Model forcontinuous variables after adjustment for age and sex. Cox proportional hazards regression was used to estimate hazard ratios (HRs) for all-cause mortality among patients with different glucose status and 4 models of adjustment were used

  • Patients with newly diagnosed diabetes had the highest and patients with known diabetes had higher mean values of CRP, white blood cell count, erythrocyte sedimentation rate, fibrinogen, lactate dehydrogenase, blood urea nitrogen and fasting glucose than patients with either normal glucose or hyperglycemia.
  • Patients with known diabetes and newly diagnosed diabetes had higher COVID-related complications including ARDS (3.1-10.5% vs 0.8-3.1%), acute kidney injury (15.3-17.0% vs 1.5-3.1%), shock (11.2-23.4% vs 2.3-4.7%), and hypoalbuminemia (36.7-39.4% vs 10.8-19.4%), as well as higher severe or critical types of COVID-19 (82.7-89.4% vs 61.4- 72.1%) compared with patients with normal glucose or hyperglycemia
  • HR of mortality for known diabetes became higher than that for newly diagnosed diabetes after additional adjustment for using glucose-lowering drugs before hospital admission and during hospitalization, and using corticosteroid

This study raises a number of interesting questions involving altered beta cell function and inflammation related to the newly diagnosed diabetes. I will be discussing this topic more in future posts.