The risk was higher in the three months following infection, and returns to baseline after 23 weeks for diabetes, and seven weeks for cardiovascular diseases. This means there is not a long-term increase of risk for patients who contracted the virus.
The population-based study is published today by King’s researchers in PLOS Medicine.
The information provided by this very large population-based study on the longer-term effects of COVID-19 on development of cardiovascular conditions and diabetes will be extremely valuable to doctors managing the millions of people who have had COVID-19 by now. It is clear that particular vigilance is required for at least the first 3 months after COVID-19.– Professor Ajay Shah, BHF Chair of Cardiology and Executive Dean of the Faculty of Life Sciences & Medicine
In the new study, researchers investigated whether a sample of COVID-19 patients developed new cases of diabetes and cardiovascular diseases at higher rates than a sample of people who have never had the disease in the year following infection.
They analysed anonymised medical records from more than 428,000 COVID-19 patients, and the same number of control individuals, matched by age, sex, and family practice.
The analysis showed that COVID-19 patients had 81% more diagnoses of diabetes in the first four weeks after contracting the virus and that their risk remained elevated by 27% for up to 12 weeks after infection.
COVID-19 was also associated with a six-fold increase in cardiovascular diagnoses overall, mainly due to the development blood clots in the lungs and irregular heartbeat. The risk of a new heart disease diagnosis began to decline five weeks after infection and returned to baseline levels or lower within 12 weeks to one year.
Based on these findings, they recommend that doctors advise their patients who are recovering from COVID-19 to reduce their risk of diabetes through a healthy diet and exercise.
Lead author Emma Rezel-Potts concludes, “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.”