Patients hospitalized for severe COVID-19 have permanent changes in their cholesterol 3 months after recovery, according to a study from the University of Oslo. This increases the risk of heart disease later in life.
Many doctors and scientists have wondered if COVID-19 affects people’s health later in life. Several recent studies have shown that there is a relationship between COVID-19 and heart disease. Does being severely ill with COVID-19 increase the risk of heart disease?
“Recent studies have indicated that COVID-19 increases the risk of cardiovascular disease. However, the mechanisms for this are still unclear,” says Ida Gregersen, a researcher at the University of Oslo and Oslo University Hospital.
Norwegian researchers found that patients, who were hospitalized with severe COVID-19, had permanent changes in their cholesterol after they recovered.
“We believe that COVID-19 increases the risk of developing heart disease later in life, and that these changes are a possible explanation for this increased risk,” says Bente Halvorsen, a professor at the University of Oslo and lead researcher on the study.
LDL cholesterol increases the risk of heart disease
Cholesterol is one of the fatty substances in the body and is an important building block of the body. There are different types of cholesterol, one of which is LDL, which is made up of several LDL particles.
“The LDL cholesterol is responsible for transporting fats in the body and is sometimes called ‘bad cholesterol,'” Gregersen says.
It is called bad cholesterol because high levels of LDL cholesterol in the blood increase the risk of heart disease and stroke.
“It is a well-known fact that the risk of cardiovascular disease increases with higher levels of low-density lipoprotein in the blood. In addition, the risk also increases when there are changes in the composition of LDL particles,” she says.
Changes in LDL particles observed in patients who recovered from severe COVID-19
The researchers observed such changes in LDL composition in these patients, 3 months after they had recovered from severe COVID-19.
“Patients who have had severe COVID-19 have had the composition of these LDL particles change after they got sick. Among other things, they contain many inflammatory substances,” says Gregersen.
These changes can affect LDL particles to aggregate in the walls of blood vessels. This can drive the development of heart disease in the long term.
“So we think that severe COVID-19 causes long-term changes in the composition of LDL particles, that is, in the body’s system for transporting fats around the body. It could lead to an increased risk of cardiovascular disease later on, but we don’t. I don’t know.” So after,” she says.
We can prevent heart disease when we know more about the risks
According to the researchers, it is important that people who have severely contracted COVID-19 are aware of their risk of developing cardiovascular disease.
“It is very important for patients who have severely ill COVID-19 to know that they may have an altered cholesterol composition in their body. We know from previous research that they have a higher risk of developing cardiovascular disease later in life,” says Halvorsen.
By identifying people who have an increased risk, it is possible to engage in preventive measures. Among other things, there are effective measures aimed at people who have high levels of LDL cholesterol in their blood.
“The more we know, the better we can prevent and treat this risk,” she says. “We have tools to address the risk of heart disease in people with high LDL.”
Lifestyle factors such as smoking and obesity are also important
Halvorsen recommends that those who become severely ill with COVID-19 see their GP. To find out if you have a higher risk of developing cardiovascular disease, you can order a blood test.
“We cannot say with certainty that these patients will actually develop cardiovascular disease. Environmental factors and lifestyle factors such as smoking, obesity and high blood pressure will play a role in whether this progresses further,” says Halvorsen.
A new method can isolate and measure changes in LDL particles
Researchers investigated a specific property of LDL particles, called LDL aggregation, which occurs when LDL particles clump together in blood vessels. To investigate LDL aggregation, the researchers collaborated with the Wihuri Research Institute in Finland who have created a method that can isolate and measure these changes in LDL.
“We know that LDL can aggregate, i.e. clump together. However, this method can obtain quantitative measures that can show if there is a change in LDL accumulation in the blood. We can therefore use this as a measure of cardiovascular disease risk,” Halvorsen explains.
Persistent changes in LDL indicate active immune activation
“The fact that these differences in LDL composition appear 3 months after patients have recovered from COVID-19 is significant,” Halvorsen notes.
LDL has a half-life in plasma of only a few days before it is regenerated. Half-life means the time it takes for LDL to decrease by half. After a few days, new LDL is produced. Normally, one would therefore expect the changes in LDL composition to disappear after a few days.
“When we still see changes in the composition of LDL after 3 months, it indicates that COVID-19 could lead to long-term disruptions in the system that transports fats in our bodies. In addition, LDL carries inflammatory markers. This shows us that there is no The body’s immune system is still activated 3 months after recovering from COVID-19,” explains Halvorsen. The professor thinks the results are surprising.
“We’ve seen huge differences in the way LDL is grouped together, between healthy people who didn’t get COVID-19, and those who are sick, who were sick and hospitalized with severe COVID-19. To me, that’s very exciting. This is a new finding, It will be interesting to see how that develops further,” says Halvorsen.
Blood samples from Norway’s first COVID-19 patients have been analyzed
The researchers analyzed blood samples from 66 people hospitalized with severe COVID-19, taken during a check-up 3 months after they were discharged from the hospital. These patients were hospitalized during the first wave of COVID-19 in March 2020. The researchers then compared these samples with 42 healthy adults who served as controls, and examined whether factors such as age, gender and ethnicity played a role.
More research is needed
Halvorsen concludes, “Our data point to novel mechanisms of increased cardiovascular disease risk in patients with COVID-19. However, further, larger studies that can examine associations between these LDL characteristics and the development of cardiovascular disease are needed, to further support our findings.” Larger”.
Oland, T.; et al. (2023). Low-density lipoprotein particles carrying proinflammatory proteins with an altered aggregation pattern detected in COVID-19 patients 3 months after hospital admission. Infection Journal. doi.org/10.1016/j.jinf.2023.02.024.