Since the start of the pandemic, we have learned a lot about the disease that underlies it. We now view COVID-19 not just as a respiratory disease, but as a multisystem disease.
Many studies have reported on complications that can arise from severe COVID infection, such as heart failure or worsening of existing diabetes.
Heart disease and diabetes are part of a group of common but often preventable diseases called cardiometabolic diseases. While these immediate complications remain a priority, we also know that the virus can affect people’s health months after initial infection.
Results from US Department of Veterans Affairs databases identified an increased burden of various conditions, including heart disease and diabetes, up to six months after COVID infection. Meanwhile, a UK preprint (a study yet to be peer-reviewed) reported that cardiovascular complications were high for up to 49 weeks after infection.
Overall though, very few studies have considered long-term cardiometabolic outcomes after COVID. So, in our new study, we sought to learn more about heart disease and diabetes risk for one year after COVID infection. We found that although the risk was higher shortly after COVID, it decreased again over the course of the year.
We used a national database of electronic primary care records covering over 13 million people in the UK. From these, we identified over 428,000 COVID patients and selected the same number of control participants (who did not have a recorded COVID diagnosis), matched by age, gender, and GP clinic.
We then looked at whether COVID patients developed diabetes and heart disease at higher rates. We analyzed data during the year before their COVID infection (from the date of infection of their equivalent participant for matched controls) and up to one year after. Considering this baseline measurement allowed us to more accurately identify any post-COVID changes.
We found that heart disease and diabetes were slightly higher in COVID patients in the year before infection, compared to controls. We included this baseline risk and other key factors that may affect outcomes, such as BMI and blood pressure, in our analysis.
The risk of being diagnosed with heart disease and diabetes was highest in the first four weeks after contracting the virus. We identified 81% more diabetes diagnoses during this period compared to controls. The risk remained elevated at 27% between four and 12 weeks after infection and returned to baseline after 23 weeks.
Meanwhile, we saw a six-fold increase in heart disease diagnoses in the four weeks following COVID infection. The greatest risk was pulmonary embolism (a blood clot in the lungs), which increased 11-fold. Diagnoses of heart disease declined five to 12 weeks after infection and returned to baseline levels of 12 weeks to a year later.
We actually observed that the risk of heart disease fell below baseline levels in the year following COVID infection. This may be due to increased engagement in COVID-related health care.
How does this work?
Studies indicate that SARS-CoV-2 could directly infect pancreatic cells, leading to reduced insulin production. When we don’t have the right levels of insulin to regulate our blood sugar, it can lead to diabetes. COVID infection could also reduce physical activity, another factor we know can affect blood sugar levels.
It should also be noted that COVID-related medical consultations may have provided additional opportunities to detect previously undiagnosed diabetes. It may therefore be that the COVID infection did not cause the diabetes in all cases.
When it comes to heart disease risk, likewise, there are likely a variety of factors at play. We know that COVID can lead to organ damage, including the heart. The immune response to COVID infection, which triggers a process called inflammation, is also important. This process can affect some of our cells that are important for heart function.
The differences we observed in when heart disease and diabetes risk occur are perhaps not surprising given what we know about how these conditions typically present. Heart disease is associated with events (such as a heart attack) that may lead to a more immediate diagnosis, while diabetes may take time to diagnose, which may contribute to a later decrease in risk.
Although electronic health records have been a powerful tool for us to analyze a large group of people over time, a limitation of this type of source is that we can only use the data that is available there. For example, we had no information on alcohol consumption or physical activity, which could have affected the results.
It is also possible that the risk status was misclassified in some cases. For example, control patients may have had COVID but were not tested or did not inform their GP.
Additionally, we need to be aware of the limitations of observational studies. We can’t say that COVID necessarily caused this increase in heart disease and diabetes diagnoses — just that there was a connection.
Although we don’t understand precisely why we saw the trends we saw, the fact that the risks of heart disease and diabetes decreased in the year following COVID infection is reassuring.
It appears that patients are most at risk during the first four weeks following COVID infection, especially diagnoses of pulmonary embolism and diabetes. As the risk of diabetes remains elevated for at least three months, clinical and public health interventions aimed at reducing the risk of diabetes, such as advice on healthy diet and exercise, could be directed towards the recovery of COVID patients. .
And if you’re someone who has recently recovered from COVID, it pays to be especially vigilant about your health. See a doctor if you feel something is wrong.
Disclaimer:- This story has not been edited by Sen Times staff and is automatically generated from news agency feeds.
Authors: Emma Rezel-Potts, Research Associate in Translational Epidemiology and Public Health, King’s College London