February 18, 2021
Although half of patients with diabetes hospitalized with COVID-19 will be discharged from hospital within a month of admission, a fifth will have died, suggest the latest results from the French CORONADO study.
The investigation, initiated during the first wave of the pandemic, has already accumulated a large amount of data, with early findings published in May 2020 suggesting 10.6% of patients with type 2 diabetes and COVID-19 and 5.6% of those with type 1 diabetes and COVID-19 died within 7 days of hospital admission.
The current outcomes at 28 days were presented at a press conference held by the Francophone Foundation for Diabetes Research (FFRD) on February 3, and were just published in Diabetologia.
Identifying the Patient Phenotype
For the study, 2796 patients with diabetes were hospitalized with COVID-19 at 68 institutions across France between March 10 and April 10, 2020, and followed for 28 days.
The data analysis was conducted on the basis of "patient phenotype."
"We put together all the relevant medical information: history, usual treatment, clinical and biological presentation, and hospital prognosis," says lead author Matthieu Wargny, MD, L'Institut du Thorax, INSERM, CNRS, University Hospital of Nantes, France.
The primary outcome was tracheal intubation and/or death.
"We were also interested in positive outcomes, like returning home or to a care home, transfer to another hospital, or follow-up care," Wargny notes.
Death Rate of 20%
Of the participants, 63.7% were men, average age was 69.7 years, and median body mass index was 28.4 kg/m2. In addition, 44.2% of patients presented with microvascular complications and 38.6% had macrovascular complications.
After 28 days, 577 patients (20.6%) had died and 1404 (50.2%) had been discharged. The median duration of hospital stay was 9 days.
"We also found that 12.2% of patients were still in hospital and 16.9% had been transferred," says Wargny, who underlines that the data were gathered during the first wave of the pandemic and would certainly be different today, with in-hospital mortality having decreased among patients with COVID-19.
He adds that the researchers "were able to identify the principal prognostic risk factors, both negative and positive."
Among the risk factors that boded poorly, advancing age was the most important. This was followed by a history of microvascular complications, particularly kidney and eye damage, dyspnea on admission, and inflammatory markers (white blood cell count, raised C-reactive protein, and elevated aspartate transaminase).
Among the positive risk factors, researchers identified routine treatment with metformin and a history of COVID-19 symptoms before hospitalization.
On the other hand, blood glucose level was a neutral prognostic factor, a result that Wargny describes as "unexpected."
Another neutral factor was treatment with DPP-4 inhibitors. Statin therapy was a negative prognostic factor, with a 42% increased risk of death among patients on statins for whom complete data were available.
However, "these are post-hoc studies that are not able to answer questions over the treatment of diabetic patients hospitalized with COVID," warns Wargny. In other words, it is not possible to draw conclusions on the impact of one treatment over another.
Subject to publication, other work by the team focuses on prognostic differences based on sex, degree of microangiopathic impairment, and impact of bariatric surgery.
"We have reassuring data for patients who have undergone bypass surgery or sleeve gastrectomy," notes Wargny.
Overall Risk of Dying From COVID-19 Remains Low in Those With Diabetes
In a statement, Faye Riley, senior research communications officer at Diabetes UK, said: "This study supports previous research that has shown that certain risk factors, such as older age and a history of diabetes complications, put people with diabetes at higher risk of harm if they catch coronavirus. It also provides fresh insight into factors that are linked with a quicker recovery from the virus.
"Understanding which people with diabetes are at a higher risk if they're admitted to hospital with coronavirus will help to improve care and save lives. But it's also important to remember the overall risk of dying for people with diabetes remains low and has reduced over the past year."
"Since the data in the study was captured, our understanding of how to treat coronavirus has grown, and new drugs shown to reduce risk of death are now in routine use," she emphasized.
The study received funding from the FFRD, supported by Novo Nordisk, MSD, Abbott, AstraZeneca, Lilly; Federation Franc¸aise des Diabetiques; Societe Francophone du Diabete; and Fonds de dotation du CHU de Nantes. (CORONADO project: Sanofi, Air Liquid Healthcare, Novo Nordisk, NHC, Allergan, LifeScan.) Wargny has reported relationships with Novo Nordisk.