A Study Linking E-Cigs to Heart Attacks Was Just Retracted – What Does That Mean for Vaping's Health Risks?

By Ed Cara on at

This week, a study that had suggested using e-cigarettes could increase the risk of heart attack was retracted, following an investigation by the journal’s editors that deemed its findings “unreliable.” But does the retraction mean vaping is safe, and should we be concerned about the validity of other vaping research?

The study was published last June in the Journal of the American Health Association (JAHA) by a pair of researchers from the University of California San Francisco. Using population data, they found that people currently vaping or smoking cigarettes were more likely to also have had a heart attack. Those who reported using e-cigarettes and cigarettes at the same time had an even higher associated risk than using either alone, the study found.

At face value, the findings lined up with similar research pointing to health risks in e-cigarette and cigarette users, as well as a greater possible risk among users of both. The study received some media attention, though Gizmodo did not cover it. But it wasn’t long before some scientists and journalists began to criticize the study.

One major flaw, highlighted in a letter sent to the JAHA in January by several scientists, was that the researchers had not tried to exclude cases where people had a heart attack before they reported ever vaping. Another criticism was that the authors had not accounted for the smoking history of current vapers in their analysis. Because the effects of smoking, including on the heart, can take years to fade away, many vapers who previously smoked could have been more likely to have a heart attack, regardless of their new vaping habit.

The pushback was enough for some of JAHA’s editors to look again at the study and how it was peer-reviewed. There, they found out that the reviewers had pointed out these critiques to the authors and asked them to redo their analysis, but the “reviewers and editors did not confirm that the authors had both understood and complied” with their request, according to the retraction notice.

The authors were then asked to correct their work but ran into further stumbles. They told the journal that they no longer had access to the database originally used for their study and were unable to do another analysis by the journal’s deadline. Given these issues, the journal’s editors wrote, they were concerned the study conclusions were unreliable and retracted it.

“A retraction is not a trivial matter,” Brad Rodu, a researcher at the University of Louisville in Kentucky and one of the study’s early critics, told VICE. “It’s a significant action. Saying it was a mistake is too weak.”

The retraction is a flashpoint in what’s become an increasingly contentious debate between scientists and public health experts who study vaping and e-cigarettes. Many experts, particularly in the harm reduction world, believe that e-cigarettes represent one of the best ways to ease people off cigarette smoking, which is undoubtedly one of the most damaging habits a person can have.

But other experts argue that too much is still unknown about their potential risk, especially long-term, for vaping products to be embraced wholeheartedly. They contend, with mixed evidence, that vaping may not really help people quit smoking any better than other options; many people instead just become dual users. Meanwhile, plenty of teens who otherwise might have never touched nicotine are becoming vaping fans.

Last year, the debate amped up even more, when waves of vape users across the country began coming down with severe, sometimes fatal, lung disease. The outbreak, which peaked in September 2019 but hasn’t completely ended yet, has involved over 2,600 cases along with 68 deaths in the US.

The majority of these cases were eventually linked to unregulated vaping products made with toxic oily additives like vitamin E that were used to vape cannabis, not store-bought e-cigarettes with nicotine. But the crisis nonetheless fuelled calls for new laws in the US to restrict and even ban flavoured e-cigarettes – policies that many experts bemoaned as unwarranted and only likely to drive more people to smoke.

Where does that leave us? Well, just as a single study alone can’t tell us for certain whether vaping is harmful, one retracted study can’t tell us that it’s not. Other research still suggests that there’s a real link between e-cigarette use and potential bodily harms, including to our heart and circulation. None of this research is a smoking gun, but science works by adding up all the best evidence we can, adjusting for or tossing out weaker evidence, and making a judgement call.

Right now, the evidence does clearly point to e-cigarettes being safer than cigarettes, tainted products not included. But it’s tougher to say for sure that e-cigarettes have helped drive down the rate of cigarette smoking, which has been on the decline for decades, or that these products are any better for helping smokers quit than other available options. And yes, there’s still a lot we don’t know about how vaping could affect health over the long haul or what will happen to the new generation of vaping teens as they age.

The most practical advice I can give – if the hardest to follow, given nicotine’s addictive nature – is to avoid both e-cigarettes and cigarettes altogether.

Featured image: Dante Diosina Jr. (AFP via Getty Images)