People with diabetic eye disease have a five-fold increased risk of requiring intubation when hospitalised with Covid-19, according to a new study which calls for better clinical monitoring of patients with this complication.
The study, published in the journal Diabetes Research and Clinical Practice on Tuesday, identified for the first time the risk associated with diabetic retinopathy and Covid-19.
This eye disease is a common complication of diabetes and is caused by damage to the small blood vessels in the eye, the researchers, including those from King's College London in the UK, explained.
In the study, the scientists investigated 187 people with diabetes hospitalised with Covid-19 between March and April 2020.
They found that 67 patients had diabetic retinopathy, a majority with background eye damage.
Of the 187 patients hospitalised with severe Covid-19, the scientists said 26 per cent were intubated, and 45 per cent of these patients had retinopathy.
According to the study, retinopathy was associated with a five-fold increased risk for intubation with no association observed between this condition and mortality.
"This is the first time that retinopathy has been linked to severe Covid-19 in people with diabetes," said study co-author Antonella Corcillo from King's College London.
"Retinopathy is a marker of damage to the blood vessels, and our results suggest that such pre-existing damage to blood vessels may result in a more severe Covid-19 infection requiring intensive care treatment," Corcillo added.
According to the researchers, people with diabetes are at high risk of vascular complications affecting the large and small blood vessels.
"We hypothesise that the presence of diabetes related vascular disease such as retinopathy may result in greater vulnerability and susceptibility to respiratory failure in severe Covid-19," Corcillo said.
The scientists believe looking for presence or history of retinopathy or other vascular complications of diabetes may help health care professionals identify patients at high risk of severe Covid-19.
Citing the limitations of the study, the researchers said it included a relatively small sample size and was unable to identify a causal relationship between retinopathy and severe Covid-19 outcomes.
"Further studies are required to investigate the possible mechanisms that explain the links between markers and manifestations of diabetic vascular disease such as retinopathy and severe Covid-19," Corcillo added.
