Smoking, vaping increases risk of death from COVID, study finds

Smokers and vapers are more likely to have a severe case of COVID-19 or die of the disease, a new study finds.

People who reported use of tobacco products prior to their hospitalization were 39% more likely to be put on mechanical ventilation than non-smokers.

What's more, they were 45% more likely to die.

Although it's well-known that smoking and vaping damages the lungs and suppresses the immune system, making people more susceptible to COVID-19 and less likely to fight off the illness, there is limited information on the link between smoking and COVID-19 severity.

"Like everybody else, we were very worried about COVID and trying to understand what are the important risk factors that predispose people for more severe outcomes," first author Dr. Aruni Bhatangar, a professor of medicine, biochemistry and molecular biology at the University of Louisville, told ABC News. "And we were concerned about if tobacco use may be affecting COVID severity, as well as outcomes."

He added, "There's been a lot of work, a lot of observational work that's been done in the area with claims and counterclaims. Some people say smoking's bad, some people say not so bad. So we thought that we really did need a large, comprehensive study to address the issue."

For the study, published in scientific journal PLOS One, the team looked at data from the American Heart Association COVID-19 Cardiovascular Disease registry including more than 4,000 people over age 18 who were hospitalized with COVID-19 between January 2020 and March 2021.

People were classified as smokers if they reported current use of traditional cigarettes or e-cigarettes. However, the study did not evaluate if there was a difference in risk level between those who vape versus those who smoke.

Researchers -- from the AHA Tobacco Regulation Center and the University of Louisville, in Kentucky -- found smoking or vaping were linked to more COVID-19 deaths and hospitalizations regardless of the patients' age, sex, race/ethnicity or medical history.

Bhatangar said the risk estimates were a bit surprising and even "higher than we thought it would be."

However, some subgroups were more likely to be at risk of death from COVID-19 than others.

Smokers between ages 18 and 59 were more likely to die from the diseases than those who are age 60 and older, despite COVID's propensity to affect the elderly.

"That was a surprising finding and we thought about this part for a while, and it seems like maybe because the basal death rates in that age group were lower, so any risk factors are more likely to be pronounced than [in] people who are over 60 years old," Bhatangar said.

Additionally, white smokers had a higher risk of COVID death than Black and Hispanic patients, groups that have been disproportionately affected by the virus and its complications. However, Hispanic patients were more likely to be put on a ventilator.

Smoking was also linked to a higher risk of death among smokers with underlying conditions such as obesity, diabetes, hypertension and chronic kidney disease as well as those receiving anticoagulants before their hospitalization.

The team says its study has some limitations including lack of complete smoking history for participants and no information on how many cigarettes or other tobacco products the patients used per day or for how many years.

For future research, Bhatangar said he is interested in studying how smoking affects vaccine outcomes, whether smoking increases the risk of infection, the difference between current smokers and former smokers, and the same things among a larger vaping group.

"The obvious message is that if you're a smoker you do have a higher risk, [then] the general advice is always quit smoking altogether," he said. "But the more important part ... is with physicians and admitting hospitals, it is important to take medical history [into account] because maybe smokers are more likely to turn onto severe disease and may need more aggressive medical care because they are more likely to turn onto ventilators."