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  • Researchers say people with COVID-19 have a higher risk of heart health issues and diabetes in the 12 weeks following an infection.
  • They note that those risks appear to decrease after the initial 12 weeks.
  • Experts say there are a number of potential reasons for the increased risk, including inflammation and cell dysfunction.
  • They also note that the underlying conditions in some people with COVID-19 are also risk factors for diabetes and cardiovascular disease.

COVID-19 may not cause cardiovascular disease or diabetes, but the inflammation caused by a novel coronavirus infection could put people at higher risk of developing these chronic health conditions.

Primary-care patients who contracted COVID-19 had a six-fold increase in cardiovascular diagnoses and had 81 percent more diabetes mellitus diagnoses in the first four weeks after contracting the virus, according to a newstudyfrom researchers at King’s College London.

The cardiovascular risk rose for pulmonary embolism, atrial arrhythmia, and venous thrombosis.

Researchers also reported that the risk of a diabetes diagnosis remained 27% higher for up to 12 weeks after infection. The risk of a new heart disease diagnosis began to decline five weeks after infection and returned to normal or lower by 12 weeks to one year after infection.

However, researchers did not find a long-term association between COVID-19 and cardiovascular disease and diabetes when patient records from follow-ups 12 to 52 weeks after initial illness were examined.

“Our findings are reassuring that cardiovascular disease and diabetes mellitus risks decline within a year after COVID-19,”Emma Rezel-Potts, Ph.D., the study’s lead author and a research associate at King’s College London, told Healthline.

“Our study can’t tell us about the possible mechanisms that lead to cardiometabolic outcomes following COVID-19 infection, but we can look to other research in the field,” Rezel-Potts added. “The virus is believed to trigger events which can affect multiple systems in the body, including a dysregulated immune response and cell dysfunction, which might explain the associations we’re seeing. Another possibility with diabetes is that there is direct infection of SARS-CoV-2 in pancreatic cells.”

“It could also be the case that COVID-19 reduces physical activity leading to greater insulin resistance,” she continued. “Then again, it might be that the COVID-19 diagnosis leads to more contacts with medical services, which then leads to increased opportunities to detect previously undiagnosed diabetes.”

The findings were based on a review of the medical records of 428,000 COVID-19 patients, which were compared to a control group of the same size.

Dr. Swapnil Khare, an endocrinologist at Indiana University Health, praised the study for its large sample size. She added that the findings will add to a significant body of research demonstrating a link between COVID-19 infections and elevated risk of diabetes and cardiovascular disease.

“COVID-19 is a multi-system disease. It has implications far beyond the lungs,” Khare told Healthline. “It’s well-known that viral infections, including COVID-19, cancausetype 1 diabetes. For type 2, there are multiple factors in acute COVID-19 infection that can raise risk, including an increase in inflammatory markers like interleukins and cytokines. The cytokine response to COVID infection is well-known.”

Some medications used to treat COVID-19 symptoms, notably steroids, also canincreaseblood-sugar levels, Khare noted.

Dr. Allan Stewart, a cardiothoracic surgeon at HCA Florida, told Healthline that people who are overweight, have an unhealthy diet, and don’t get adequate exercise, which are among the main risk factors for cardiovascular disease and diabetes, also represent the population that tends to have the most serious COVID-19 complications.

“At their core, cardiovascular disease and diabetes are conditions of chronic inflammation,” said Stewart. “What this study shows is that there are a lot of people who are being kicked over the edge to one of these chronic conditions by COVID.”

In addition to vaccination, Stewart said, “we can reduce the risk of severe COVID by getting people to eat right and lose weight because, by and large, that’s the population that’s at risk.”

“The information provided by this very large population-based study on the longer-term effects of COVID-19 on the development of cardiovascular conditions and diabetes will be extremely valuable to doctors managing the millions of people who have had COVID-19 by now,”Dr. Ajay Shah, the executive dean of the Faculty of Life Sciences & Medicine at King’s College London, said in a statement. “It is clear that particular vigilance is required for at least the first 3 months after COVID-19.”

“Clinical and public health interventions focusing on reducing diabetes risk among those recovering from COVID-19 over the longer term may be very beneficial,” added Rezel-Potts.