• Posted September 7, 2021

Vaping Raises Blood Clotting Risks, Harms Small Arteries: Study

Nicotine-laden e-cigarettes raise a user's risk of blood clots, damage small blood vessels and can also raise heart rate and blood pressure, a new study finds.

The effects are similar to those caused by traditional cigarettes, and raise the concern that long-term vaping could help cause heart attacks or strokes, the Swedish research team warned.

"Our results suggest that using e-cigarettes that contain nicotine have similar impacts on the body as smoking traditional cigarettes," said study author Gustaf Lyytinen, a clinician at Helsingborg Hospital and researcher at the Karolinska Institute in Stockholm. His team presented the findings this week at the virtual annual meeting of the European Respiratory Society.

"This effect on blood clots is important because we know that in the long-term this can lead to clogged-up and narrower blood vessels, and that of course puts people at risk of heart attacks and strokes," Lyytinen explained in a society news release.

One U.S. expert wasn't surprised by the new findings.

Nicotine, whether it's found in traditional or electronic cigarettes "can lead to heart attack and stroke," said Dr. Len Horovitz, a pulmonary specialist at Lenox Hill Hospital in New York City. "Another reason why e-cigarettes should not be thought of as safer than cigarettes."

In the new study, Lyytinen' team conducted experiments with 22 women and men aged 18-45 who were occasional smokers but otherwise healthy.

Participants were tested before and after taking 30 puffs from an e-cigarette containing nicotine, and before and after 30 puffs from an e-cigarette without nicotine. The two tests were conducted on separate occasions, at least one week apart. On each occasion, the researchers measured heart rate and blood pressure and collected a blood sample before the volunteers used the e-cigarettes, then 15 minutes after use and again 60 minutes after use.

Puffing on e-cigarettes containing nicotine led to immediate short-term changes in the volunteers, including an average 23% increase in blood clots after 15 minutes, with levels returning to normal after an hour, the study found.

There was also an increase in average heart rate after vaping -- from 66 to 73 beats per minute -- and a rise in average blood pressure from 108 to 117 mmHg, the researchers said.

In one more finding, high-tech visualization using laser technology showed that the volunteers' small blood vessels became temporarily narrower after they vaped with nicotine.

None of these effects occurred after the participants used e-cigarettes without nicotine, the study authors noted.

That makes sense, because nicotine is known to boost levels of hormones such as adrenaline, which can raise the the odds for blood clots, Lyytinen's group noted.

Patricia Folan directs the Center for Tobacco Control at Northwell Health in Great Neck, N.Y. She wasn't involved in the new study, but agreed with Horovitz that vaping is far from harmless.

"E-cigarettes in their many forms were brought to market without proper regulation," Folan said. "Their safety and effectiveness in assisting smokers to quit was not proven or demonstrated with supporting research."

Smokers may believe that vaping can help them kick the nicotine habit, but instead smokers "often become dual users of both the vape products and combustible cigarettes, frequently preventing them from engaging in actual quit attempts," Folan said.

While larger studies are needed to confirm the Swedish findings, research like this can help "contradict the advertising, marketing and social media influencing to which patients [who smoke] are often exposed" and which can encourage them to take up vaping, Folan said.

Because the study was presented at a medical meeting, the findings should be considered preliminary until published in a peer-reviewed journal.

More information

The U.S. National Institutes of Health has more the risks of vaping.

SOURCES: Len Horovitz, MD, pulmonary specialist, Lenox Hill Hospital, New York City; Patricia Folan, DNP, director, Center for Tobacco Control, Northwell Health, Great Neck, N.Y.; European Respiratory Society, news release, Sept. 5, 2021