Poor long-term blood glucose management increases the risk people with diabetes will need intensive care if they contract Covid-19, a study suggests.
Although it was known that having type 2 diabetes (T2D) raised the chances of being hospitalised and dying from Covid-19, researchers designed a retrospective cohort study to identify which patients with type 2 diabetes were most at risk of developing severe disease and needing intensive care.
Researchers used deidentified claims and electronic health record data from the US OptumLabs Data Warehouse from January 2017 to November 2020, which included 16,504 individuals with type 2 diabetes and a Covid-19 diagnosis.
After adjusting for variables, they found the average of a patient’s two to three-year HbA1c levels was significantly associated with Covid-19 severity.
Patients with poor longitudinal glycaemic control (HbA1c ³ 9%) were 48% more likely to be admitted to intensive care with Covid-19 compared with patients who had adequate longitudinal glycaemic control (HbA1c 6% – 9%), the researchers reported in BMJ Open Diabetes Research & Care.
Every 1% increase in average HbA1c levels was associated with a 12% increased risk of a patient needing intensive care for Covid-19, the study found.
‘Here, we present a potential method to use HbA1c history, which presented a stronger association with Covid-19 severity than single-point HbA1c, to identify those more at risk of intensive care due to Covid-19 in the T2D population,’ the study authors wrote.
Inadequate glycaemic control has been shown to impair the immune response to infection in people with type 2 diabetes, the researchers said.
It also created a reaction that causes molecules known as advanced glycation end-products (AGEs) to accumulate, potentially leading to a loss of lung function and respiratory efficiency.
In addition, the study found that people with type 2 diabetes who were taking metformin when they contracted Covid-19 had a 12% lower risk of needing intensive care, while those prescribed metformin and insulin had an 18% lower risk and those on corticosteroids had a 29% lower risk.
However, antihypertensive medications were not associated with a decreased risk of intensive care.
‘The combined use of metformin and insulin and the use of corticosteroids might be significant to prevent patients with T2D from becoming critically ill from Covid-19’, the study concluded.
It follows research that found that blood pressure medication could help prevent type 2 diabetes.