Monday, February 26, 2018

New Study Concludes that Vaping Causes Heart Attacks

A new study presented Saturday at the annual meeting of the Society for Research on Nicotine and Tobacco (SRNT) concludes that vaping causes heart attacks, increasing the heart attack risk for dual users beyond that of smoking alone. The research has not yet been published but was presented as a poster at the conference.

The study was a cross-sectional analysis of nearly 70,000 respondents to the combined 2014 and 2016 National Health Interview Surveys (NHIS), a nationally representative survey of health risk factors and outcomes in U.S. adults. Respondents were asked to report their current vaping and smoking statuses and to report whether they had ever had a heart attack. The researchers found that there was a significant association (odds ratio = 1.8) between daily e-cigarette use and having experienced a heart attack. The analysis controlled for level of current cigarette use.

Based on this observation, the study concludes that daily e-cigarette use doubles the risk of heart attacks.

The Rest of the Story

Hold your horses.

Before accepting the conclusion that vaping causes heart attacks in unsuspecting smokers, remember the old adage: correlation does not equal causation. This study is a perfect demonstration of that phenomenon.

Because this is a cross-sectional study, and because respondents were asked whether they had ever had a heart attack, one cannot determine whether the heart attacks followed e-cigarette use or preceded it. In other words, we do not know that vaping preceded the heart attack for any of the subjects. It is entirely possible that in most of these cases, the smokers suffered a heart attack and then started vaping in an attempt to quit smoking. In fact, I believe that is the most likely explanation for the observed study findings.

It is not even biologically plausible that vaping could increase the risk of cardiovascular disease beyond that of smoking. Why? Because the cardiovascular effects of tobacco smoke saturate at a very low level, meaning that it takes only a little exposure to increase your risk. But beyond that, there is little additional risk.

On the other hand, it is quite plausible that smokers make quit attempts after experiencing a heart attack and that in recent years, these quit attempts have often involved the use of e-cigarettes.

It is true that many of the adverse effects of smoking were first observed in cross-sectional studies. However, these were followed up with longitudinal studies that confirmed the findings. Before we reach a conclusion on whether vaping poses a heart attack risk, we need longitudinal studies. This single cross-sectional study is not enough because there is no way to tell the direction of the observed association between current use of e-cigarettes and having experienced a heart attack in the past.

Although I question the validity of the study's conclusions, it is still important to emphasize that smokers who use e-cigarettes should aim to quit smoking completely. The full health benefits of vaping will not accrue to smokers unless they quit smoking completely. Dual use - if the cigarette consumption drops substantially - will reduce respiratory disease risks, but it will not reduce cardiovascular disease risk because of the saturation phenomenon noted above.

Wednesday, January 24, 2018

WBUR Interview Regarding National Academy of Sciences E-Cigarette Report

Here is the link to an article on WBUR that includes edited excerpts from an interview I did regarding the new National Academy of Sciences report on electronic cigarettes.

National Academy of Sciences Report on Electronic Cigarettes Confirms that Vaping is Much Safer than Smoking and Has No Known Long-Term Health Effects

My commentary on the conclusions and implications of the National Academy of Sciences report on electronic cigarettes was just accepted as an op-ed piece in U.S. News & World Report. I expect it to be published tomorrow. For this reason, I have had to take down the original commentary. However, below I have posted the parts of the original blog post that had to be cut from the op-ed because of length concerns. Also, I will post a link to the op-ed as soon as it appears.

The key findings of the report are:

1. "There is substantial evidence that except for nicotine, under typical conditions of use, exposure to potentially toxic substances from e-cigarettes is significantly lower compared with combustible tobacco cigarettes."

2. "There is conclusive evidence that completely substituting e-cigarettes for combustible tobacco cigarettes reduces users’ exposure to numerous toxicants and carcinogens present in combustible tobacco cigarettes."

3. "There is moderate evidence that risk and severity of dependence are lower for e-cigarettes than combustible tobacco cigarettes."

4. "There is moderate evidence that second-hand exposure to nicotine and particulates is lower from e-cigarettes compared with combustible tobacco cigarettes."

5. "There is no available evidence whether or not e-cigarette use is associated with clinical cardiovascular outcomes (coronary heart disease, stroke, and peripheral artery disease) and subclinical atherosclerosis (carotid intima media-thickness and coronary artery calcification)."

6. "There is insufficient evidence that e-cigarette use is associated with long-term changes in heart rate, blood pressure, and cardiac geometry and function."

7. "There is no available evidence whether or not e-cigarette use is associated with intermediate cancer endpoints in humans. This holds true for comparisons of e-cigarette use compared with combustible tobacco cigarettes and e-cigarette use compared with no use of tobacco products."

8. "There is no available evidence whether or not e-cigarettes cause respiratory diseases in humans."

9. "There is limited evidence for improvement in lung function and respiratory symptoms among adult smokers with asthma who switch to e-cigarettes completely or in part (dual use)."

10. "There is limited evidence for reduction of chronic obstructive pulmonary disease (COPD) exacerbations among adult smokers with COPD who switch to e-cigarettes completely or in part (dual use)."

11. "While the overall evidence from observational trials is mixed, there is moderate evidence from observational studies that more frequent use of e-cigarettes is associated with increased likelihood of cessation."

12. "There is substantial evidence that e-cigarette use increases risk of ever using combustible tobacco cigarettes among youth and young adults."

13. "There is conclusive evidence that, other than nicotine, the number, quantity, and characteristics of potentially toxic substances emitted from e-cigarettes is highly variable and depends on product characteristics (including device and e-liquid characteristics) and how the device is operated."

The Rest of the Story

I agree with all of the above conclusions, other than #12, which is not wrong on its face but needs careful interpretation.

Therefore, let me say a few words about conclusion #12 above ("There is substantial evidence that e-cigarette use increases risk of ever using combustible tobacco cigarettes among youth and young adults"). It is true that youth who experiment with e-cigarettes are more likely to also experiment with tobacco cigarettes and therefore, to become smokers. It would be shocking if this were not the case because we know that youth who experiment with one risky behavior are more likely to experiment with other risky behaviors. But this doesn't necessarily mean that the experimentation with e-cigarettes is causing the youth to start smoking.

For example, there probably are not many kids who use heroin who have never taken a sip of alcohol. If you did a study, you would find that alcohol use is associated with later use of heroin. But this doesn't support the conclusion that experimenting with alcohol causes kids to become heroin junkies. It simply reflects the fact that kids who take huge health risks are more likely to already have taken smaller health risks. A youth is not going to decide to rebel one day by injecting a drug into their veins. The rebellion process would likely start with a less hazardous behavior, such as taking a toke on a cigarette and then for a very small number of kids, they would end up progressing to hard drug use.

So the important question is not whether youth who experiment with e-cigarettes are more likely to end up smoking (of course they are!), but instead, whether youth who experiment with e-cigarettes are more likely to become addicted to vaping and then be led to smoking addiction, such that without having become addicted to vaping, they unlikely would have become smokers. So far, the evidence suggests that this is not the case: very few youth have been identified who started as nonsmokers, became regular vapers, and then progressed to smoking.

Sunday, January 07, 2018

International Scientific Forum on Alcohol Research (ISFAR) is Still Hiding Conflicts of Interest of Its Members

The International Scientific Forum on Alcohol Research (ISFAR) claims to be "an independent organization of scientists that prepares critiques of emerging research reports on alcohol and health." The Forum describes itself as "an international group of invited physicians and scientists who are specialists in their fields and committed to balanced and well researched analysis regarding alcohol and health." It is "a joint undertaking of Boston University School of Medicine in the United States and Alcohol in Moderation (AIM) of the United Kingdom. Its Co-Directors are R. Curtis Ellison, MD, Professor of Medicine & Public Health, Boston University School of Medicine, and Helena Conibear, Executive Director, Alcohol-in-Moderation (AIM), UK."

The Rest of the Story

About a year and a half ago, I reported that ISFAR was hiding its conflicts of interest with Big Alcohol. At that time, ISFAR published a scathing review of a meta-analysis which concluded that moderate alcohol consumption does not reduce mortality as previously thought. The review contained statements from 14 members of ISFAR, and every one of the 14 blasted the study, with the review concluding that the study "markedly distorts the accumulated scientific evidence on alcohol and CVD [cardiovascular disease]."

It turns out that five of the Forum members who reviewed the article had conflicts of interest by virtue of either their having received research funding from the alcohol industry or serving on advisory boards of alcohol industry-funded organizations, yet none of these conflicts were disclosed.

Not only did ISFAR hide its conflicts of interest with alcohol companies on its web site, but it also hid these conflicts in a public interview.

More recently, one of the Forum members and reviewers was forced to publish a correction to a journal article because he failed to disclose that he is a beer industry consultant.

Has ISFAR reformed itself, and is it now disclosing the conflicts of interests of the reviewers who write its critiques?

The answer, unfortunately, is no.

Nowhere on its website does it list the specific conflicts of interest of its members/reviewers. Nowhere in its critiques does it disclose these conflicts of interest. And to top it all off, the biographies provided for its members do not disclose their conflicts of interest.

For example, Dr. de Gaetano's bibliography fails to disclose that he consults for the beer industry -- the precise conflict of interest for which he was forced to publish a correction in the Journal of the American College of Cardiology.

Dr. Estruth's biography states that he is a member of the Advisory Board for "ERAB." The reader is not told what ERAB stands for, hiding from the public the fact that ERAB is "supported by The Brewers of Europe, the voice of the brewing industry in Europe, whose members are the national brewing trade associations, representing more than 90% of European beer production."

Ms. Stockley's biography states that she works for the Australian Wine Research Institute, which it states is "an independent, not-for–profit research institution." But it hides the fact that this Institute is funded by the alcohol industry. Far from being independent, the Australian Wine Research Institute is actually the "wine industry’s own research organisation."

Dr. Teissedre's biography fails to disclose that his research group received alcohol industry funding.

Dr. Waterhouse's biography hides the fact that he has received alcohol industry research funding.

Dr. Skovenborg's biography fails to disclose that he was on the Board of ERAB, which is funded by the alcohol industry.

Dr. Mattivi's biography fails to disclose that he has received alcohol industry research funding.

Dr. Klatsky's biography fails to disclose that in the past, he received alcohol industry funding.

Dr. Lanzmann-Petithory's biography fails to disclose that in the past, she has received alcohol funding.

Dr. Gretkowsky's biography fails to disclose that in the past, she has received alcohol funding.

So of the supposedly "independent" and "balanced" reviewers, at least 10 of them have conflicts of interest with the alcohol industry that are not disclosed on the web site, even in their own biographies.

Unfortunately, ISFAR continues to be essentially an industry front group that is providing highly biased reviews without readily disclosing the intricate details of the financial connections of many of its reviewers to the alcohol industry.

They should not fool anybody any longer. The time to end this scam operation is now. Especially in a period in which the federal government has basically tossed scientific objectivity out the window.

Sadly, what ISFAR is doing bears a strong resemblance to the fraudulent public relations activities of the tobacco industry many years ago. 

On a personal note, I feel somewhat ashamed that the Boston University School of Medicine has been playing a role in this scam, as ISFAR has been hosted, in part, by our medical center.

On a larger note, this story illustrates why the alcohol industry-funded NIAAA study of the potential cardiovascular benefits of moderate drinking is so problematic. The background research that informs the study is tainted by serious conflicts of interest. But the worst is yet to come -- as I will reveal shortly, the research is not an objective attempt to get at the answer to this research question.