Commonly used cholesterol-lowering statins may reduce the risk of death and severity of COVID-19 disease, says a new study.

According to the American Heart Association, one in four Americans over 40 take statins to lower their cholesterol and reduce their risk of heart attack, stroke, and other cardiovascular diseases.

"While there is no 'magic bullet' to help patients who are very ill with COVID-19, statins decrease inflammation, which may help reduce the severity of the disease," said lead author Ettore Crimi University of Central Florida, Orlando.

"Results of our study clearly showed regular statin use is associated with reduced risk of death and improved outcomes in hospitalised COVID-19 patients," Crimi added.

For the study, presented at the Anesthesiology 2022 annual meeting, the team analysed the electronic medical records of 38,875 patients hospitalised for COVID-19 at 185 hospitals in the US between January 1 and September 30, 2020.

Of those patients, 30 per cent regularly used statins to treat high cholesterol. Statin users had a 37 per cent lower risk of dying from COVID-19 than those who did not use statins.

In addition, regular statin users were significantly less likely to be discharged to hospice, be admitted to the intensive care unit (ICU), or develop blood clots. They also had shorter hospital stays and spent less time on a ventilator.

While COVID-19 causes inflammation, in some cases, the immune system creates further inflammation by responding too aggressively to the infection.

This extreme reaction causes much damage to the body, including difficulty breathing and damage to the lungs, kidneys, heart, brain, and vascular system.

The anti-inflammatory actions of statins "cool the process" so that the disease is not as severe, Crimi said.

One in four Americans over the age of 40 take statins to lower their cholesterol and reduce their risk of heart attack, stroke, and other cardiovascular diseases, according to the American Heart Association, making them one of the most commonly prescribed drugs.