One in 10 coronavirus patients with diabetes died within the first seven days of hospitalization, and one in five needed a ventilator to breathe, according to a new study by French researchers.

Diabetes is one of the underlying health conditions that health experts believe put people at greater risk for developing more severe symptoms of Covid-19 and the study, published in the journal Diabetologia Thursday, seems to confirm this. 

The researchers looked at more than 1,300 coronavirus patients in 53 hospitals in France between March 10 and March 31. Most — 89% — had Type 2 diabetes; 3% had Type 1 diabetes; and the rest had other forms of the disease. A majority of the patients were men and the average age of all the patients in the study was 70.

By day seven of the study, 29% of the patients were either on a ventilator or had died. Researchers said 1 in 5 patients were on a ventilator and 1 in 10 had died, while 18% had been discharged from the hospital.