High fasting blood sugar predicts poor prognosis in COVID-19: Study

Diabetes has been uniformly reported to be associated with poor prognosis in coronavirus infections. One retrospective analysis by Yang JK in 2006 suggested that a known history of diabetes and ambient hyperglycemia or high blood sugar were independent predictors for death and morbidity in SARS patients.

"And diabetes was seen to be prevalent in approximately 50% of the patients with MERS-CoV in our systematic analysis of 637 cases," says Badawi A in his study released in 2016. However, various recent clinical studies confirmed diabetes as a major comorbidity of COVID-19.

As many authors had studied the associations between Diabetes and the corona virus, Guo et al, and Dong et al had investigated the correlation between diabetes history and prognosis of COVID-19, which analyzed 174 and 193 patients with COVID-19 respectively, but, "No study elucidated the role of fasting blood sugar level in the prognosis of coronavirus disease 2019 (COVID-19)," states Yuli Cai from the Department of Endocrinology, Renmin Hospital of Wuhan University, Wuhan, China.

"We firstly showed FBG ≥7.0 mmol/L predicted worse outcome in hospitalized patients with COVID-19 independent of diabetes history. Our findings indicated screening fasting blood sugar level is an effective method to evaluate the prognosis of patients with COVID-19," he further added. 

The cohort study was conducted in a single-center at Renmin Hospital of Wuhan University, Wuhan, China. Clinical laboratory, and treatment data of 941 hospitalized patients with COVID-19 were collected and analyzed. Outcomes of patients with and without pre-existing diabetes were compared and the associations of diabetes history and/or fasting blood sugar levels with mortality were analyzed and the following results were drawn-

1. There was a positive relationship between pre-existing diabetes and the mortality of patients who developed COVID-19.
2. FBG≥7.0 mmol/L was an independent risk factor for the mortality of COVID-19 regardless of the presence or not of a history of diabetes.

As a result, Yuli Cai and his colleagues from the Departments of Cariology, Infectious Diseases and Endocrinology at the Renmin Hospital of Wuhan University, Wuhan, China came to the conclusion that their study was the first to show that Fasting blood sugar≥7.0 mmol/L was a predictor of mortality in patients with COVID-19 independent of diabetes history. "Besides that, patients with diabetes revealed senior age and much severer inflammatory responses, as well as increased incidences of comorbidities and complications compared with those without diabetes", the authors revealed.