The risk of developing diabetes is higher in the three months after a Covid-19 infection, UK researchers have found.
A large analysis of health records from almost 430,000 Covid-19 patients and the same number of matched controls found an 81% increased risk of diabetes in the acute infection period which remained increased by 27% from four to 12 weeks later.
But the risk returns to normal after 23 weeks, the researchers from King’s College London reported in PLoS Medicine.
They also found a six-fold increased risk in cardiovascular diagnoses associated with Covid-19, which included an 11-fold increase in pulmonary embolism.
That risk began to decline five weeks after infection and returned to normal between 12 weeks and one year, the records from GP practices in England between 2020 and 2021 showed.
The researchers said it was reassuring to find no long-term increase in risk of the conditions in those who had not already been diagnosed but that patients recovering from Covid-19 should be advised to consider measures to reduce diabetes risk including healthy diet and taking exercise.
It follows previous studies that suggest Covid-19 may be linked with new onset diabetes but have often been in hospitalised patients with shorter follow up, the researchers noted.
Possible reasons have included evidence that the SARS-CoV-2 virus infects pancreatic beta cell, reduces insulin production, and promotes beta-cell apoptosis, the researchers wrote.
But Covid-19 infection may also mean less physical activity and deconditioning leading to greater insulin resistance. Contacts with medical care may also lead to increased opportunities to detect previously undiagnosed diabetes, they noted.
Study lead Emma Rezel-Pottssaid: ‘Use of a large, national database of electronic health records from primary care has enabled us to characterise the risk of cardiovascular disease and diabetes mellitus during the acute and longer-term phases following Covid-19 infection.
‘Whilst it is in the first four weeks that Covid-19 patients are most at risk of these outcomes, the risk of diabetes mellitus remains increased for at least 12 weeks.
‘Clinical and public health interventions focusing on reducing diabetes risk among those recovering from Covid-19 over the longer-term may be very beneficial.’