Two prominent vaping researchers are facing off over claims that electronic cigarettes double the risk of heart attacks in adults, muddying the science over how best to stop smoking.

Brad Rodu, a University of Louisville professor, asked the Journal of the American Heart Association to retract a study out last month by University of California, San Francisco professor Stanton Glantz.

The study, co-authored by Dharma Bhatta, claimed adult vaping was "associated with" a doubled risk of heart attack, but Glantz went farther in a blog post, saying the study represented "more evidence that e-cigs cause heart attacks."

However, when Rodu obtained the federal data, he found the majority of the 38 patients in the study who had heart attacks had them before they started vaping — by an average of 10 years earlier. In his letter to the editors, Rodu called Glantz's findings "false and invalid."

"Their analysis was an indefensible breach of any reasonable standard for research on association or causation," wrote Rodu and Nantaporn Plurphanswat, a research economist at University of Louisville's James Graham Brown Cancer Center. "We urge you to take appropriate action on this article, including retraction."

Glantz says Rodu has a history of "slicing and dicing" his and others' research "to make the effects go away."

Glantz insists vaping leads to heart attacks even if he first called his secondary analysis that included the timing of heart attacks "not statistically significant." He now says it is simply "underpowered" due to the small number of cases. It was his second study in 10 months to focus on heart attacks and vaping, using battery-powered devices to heat liquid-based nicotine into inhalable vapor.

Both of the academics have been published extensively in medical journals and are well respected in the field — even if not by each other.

Glantz highlighted his achievements: two statistics textbooks, the research behind the dangers of secondhand smoke and much of what's been learned about the tobacco industry's historical misstatements on the addictive nature of tobacco. He also noted he is "a for-real rocket scientist," having worked for NASA.

In addition, Glantz was the principal investigator on a five-year 2013 $20 million federal grant to research tobacco and e-cigarettes and serves the same role on another $20 million grant National Institutes of Health grant that runs until 2023. Glantz's two recent reports on vaping and heart attacks were funded through the first and second federal grants. He and Bhatta said in the reports that they had no financial disclosures to report.

Rodu, who New York University public health professor Ray Niaura calls a "fastidious scientist," has thousands of entries in UCSF's tobacco library, which both Glantz and Rodu cite to prove their points about the Kentucky researcher.

Glantz calls Rodu a "tobacco industry apologist" and points to documents UCSF has collected that show Rodu's connections to the tobacco industry.

Rodu says his work since 2005 has been supported by unrestricted grants to the University of Louisville from Altria (which operates Philip Morris), US Smokeless Tobacco, Swedish Match, British American Tobacco and Reynolds American. He is also a senior fellow at the Heartland Institute, a right-leaning group that doesn't disclose its funding, but says he only receives reimbursement for travel.

Rodu says he sought industry funding after the National Cancer Institute treated him as if he was unethical to suggest that smokeless tobacco was safer than cigarettes when he applied for funding there in 1995. He says he has "worked tirelessly for the elimination of combustible tobacco" and is "an advocate for science and fact-driven academic discourse to educate smokers and consumers of smoke-free alternative products."

It's not just personal. It's a matter of public health.

The dispute goes beyond researchers' wrangling because it has ramifications on efforts to lower the smoking rate. The decline in smoking has been steady, but slowed in 2018 to 13.7% from 14% in 2017. But it's still a dramatic drop from 21% in 2005, according to the Centers for Disease Control and Prevention.

Federal regulators have been weighing whether there's enough of a public health benefit to having adults quit smoking by vaping to risk hooking a new generation of young people on nicotine.

The debate over the heart research also underscores how entrenched many advocates' views are in the tobacco debate, the financial stakes for both industry and academia and how even disputed conclusions can make it into journal articles.

This sector of the industry is hot: E-cigarette sales grew from less than $200 million in sales in the fourth quarter of 2015 to more than $400 million two years later, according to a 2018 report in the journal BMJ. Companies are also rushing to introduce new versions of smokeless tobacco, also known as snuff.

The competition to prove or disprove the best way to quit smoking is also big business. It includes the fight for the $40 million in federal grants Glantz and UCSF were awarded.

Niaura, who is also the former science director at the anti-tobacco Truth Initiative, says Glantz is the most prominent researcher blaming vaping for heart attacks. Niaura has also reanalyzed some of the results of studies linking vaping with heart attacks and said "we don’t find evidence for a relationship."

"We are just not able to answer the basic question of which came first," the heart attack or the vaping, he said. "The proven link between cigarettes and heart disease came over two or three decades. E-cigarettes haven’t been around long enough."

Glantz notes the study was peer reviewed and included a secondary analysis reflecting the timing of heart attacks. But the peer-review process for medical journal articles can be less than robust, according to the co-founders of the site Retraction Watch, which monitors them.

As the publisher of several scientific journals, the American Heart Association says it follows the Committee on Publication Ethics guidelines, meaning editors ask the author to respond to any questions brought to its attention. After the author’s response, if deemed appropriate, the editors may contact the author's institution for further review. The journal may revise the publication record, if it's determined necessary.

Glantz said he was "agnostic" about vaping at first, but believes his opposition is now justified. He's led efforts to warn against the devices as a way for adult smokers to quit.

There has also been growing concern about the increase in vaping by teens.

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When the liquid in electronic cigarettes is heated up, it creates "ultra fine particles" that Glantz says "are dangerous. They cause heart attacks," citing extensive literature on particle biology.

Niaura notes, however, that the particles in e-cigarettes "are not air pollution" and are compounds that are "generally considered safe."

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What can help smokers quit?

A report out in February in the New England Journal of Medicine found smokers who used vaping rather than nicotine replacement therapies such as gum or patches, were twice as likely to successfully quit. The NEJM report did raise concerns, however, about the yet unknown risks of long-term vaping.

Joanna Cohen, a professor at the Johns Hopkins School of Public Health and director of its Institute for Global Tobacco Control, calls the data on the health effects of vaping "young and messy."

"There are dangers from e-cigarettes but most agree that they will not be nearly as bad as for cigarettes," says Cohen. "But there are dangers, so the only people who should be using e-cigs are cigarette smokers who are trying to quit."

Michael Blaha, a cardiologist and director of clinical research at Johns Hopkins ospital's Cicccarone Center for the Prevention of Heart Disease, says he doesn't raise any objections to vaping when he's discussing ways for his patients to quit smoking. He says there is "no high-quality evidence" that there is an association between vaping and heart attacks.

The American Heart Association says that if people choose to use e-cigarettes to quit smoking other tobacco products, they should have a plan to subsequently stop vaping.

Rose Marie Robertson, the group's deputy chief science and medical officer, agrees there is "no long-term safety data on e-cigarettes," but urges those trying to quit to try nicotine replacement therapies including gums and patches, combined with "multi-episode counseling and medication support as needed." These, she notes, have "decades of data" proving they are safe and effective and are FDA approved.

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