Hyperglycaemia at admission may predict COVID-19 outcomes in non-diabetics
In non-diabetic patients with COVID-19, an elevated fasting blood glucose (FBG) level at hospital admission may predict negative outcomes including risk of complications and mortality, a recent study showed.
“This two-centre retrospective study shows, for the first time, that elevated FBG (≥7.0 mmol/L) at admission is independently associated with increased 28-day mortality and percentages of in-hospital complications in COVID-19 patients without previous diagnosis of diabetes,” said the researchers.
The study included 605 consecutive patients (median age 59 years, 46.8 percent female) with COVID-19 and no prior diagnosis of diabetes, with 28-day outcomes and FBG at admission at two hospitals in Wuhan, China, between January 24 and February 10, 2020. Of these, 18.8 percent (n=114) died in hospital within 28 days and 39.2 percent (n=237) developed in-hospital complications. About 34 percent of patients had comorbidities, hypertension being the most common. All enrolled participants had CT-confirmed pneumonia. About 45 percent of patients had FBG >6.1 mmol/L and 29.1 percent had FBG ≥7.0 mmol/L.
FBG ≥7.0 mmol/L at hospital admission was an independent predictor of mortality at 28 days (hazard ratio [HR], 2.30, 95 percent confidence interval [CI], 1.49–3.55; p=0.0002). [Diabetologia 2020;63:2102-2111]
An elevated FBG at admission was also associated with an increased risk of in-hospital complications at 28 days, be it FBG ≥7.0 mmol/L (odds ratio [OR], 3.99, 95 percent CI, 2.71–5.88) or 6.1–6.9 mmol/L (OR, 2.61, 95 percent CI, 1.64–4.41) compared with FBG <6.1 mmol/L.
Other risk factors for 28-day mortality were age (HR, 1.02, 95 percent CI, 1.00–1.04; p=0.0252), male sex (HR, 1.75, 95 percent CI, 1.17–2.60; p=0.0060), and CRB-65 score* 1–2 (moderate pneumonia; HR, 2.68, 95 percent CI, 1.56–4.59; p=0.0003) and 3–4 (severe pneumonia; HR, 5.25, 95 percent CI, 2.05–13.43; p=0.0005). FBG 6.1–6.9 mmol/L at admission also showed a trend toward increased risk of 28-day mortality (HR, 1.71, 95 percent CI, 0.99–2.94; p=0.0524).
The effect of elevated FBG levels on 28-day mortality was consistent regardless of pneumonia severity (CRB-65 score 0 [mild pneumonia]: crude HR, 6.57 and 3.42 for FBG ≥7.0 and 6.1–6.9 mmol/L, respectively, vs FBG <6.1 mmol/L; CRB-65 score >0: crude HR, 1.99 for FBG ≥7.0 mmol/L vs FBG <6.1 mmol/L).
The link between elevated glycaemic levels and COVID-19-related morbidity and mortality has been explored in several studies. [J Diabetes Sci Technol 2020;14:813-821; Lancet Diabetes Endocrinol 2020;8:823-833; Lancet Diabetes Endocrinol 2020;8:813-822; J Clin Virol 2020;127:104354]
However, the effect of FBG level at hospital admission on mortality in patients with COVID-19 without diabetes has not been examined, pointed out the researchers.
“We have … demonstrated that FBG ≥7.0 mmol/L is critical to the prognosis of patients with COVID-19 [and that] the incidence of in-hospital complications increases with the elevation of FBG,” they said.
They noted that the lack of data on HbA1c may have impacted the findings, as HbA1c could have established if the elevated FBG levels at admission were due to long-term uncontrolled or stress hyperglycaemia. “However, we believe that acute hyperglycaemia is more important than long-term glycaemic control in predicting the prognosis of hospitalized COVID-19 patients,” they said.
The results suggest that glycaemic testing and control should be carried out for all patients with COVID-19, regardless of their diabetes status. “FBG can facilitate the assessment of prognosis and early intervention of hyperglycaemia to help improve the overall outcomes in the treatment of COVID-19,” they concluded.