Deficient and Unreliable Studies of Vaping and Disease

 

At least a dozen medical studies over the past few years have found that vaping is associated with heart attack, stroke, hypertension, emphysema and other lung disease, as well as diabetes (see the list at the end of this entry).  The studies are cross-sectional; they are drawn from population samples at one point in time.  They only produce associations, but those are then inflated to imply or outright claim that vaping causes those disease conditions.  The studies appeared in respected medical journals and, together, form a powerful disincentive for smokers to switch to vaping.  They also add fuel to the regulatory fire to suppress vape products, which are actually vastly safer than cigarettes. 

My research group has published a new analysis entitled, “Cross‑sectional e‑cigarette studies are unreliable without timing of exposure and disease diagnosis,” in the journal Internal and Emergency Medicine.

Our analysis shows that the dozen are irrevocably deficient and unreliable.  Some used data from National Health Interview Surveys (NHIS), the Behavioral Risk Factor Surveillance System (BRFSS), or the FDA’s Population Assessment of Tobacco and Health (PATH) surveys, all of which profile participants who smoked and/or vaped and who had ever been diagnosed with numerous diseases.  However, there is absolutely no information in the NHIS or BRFSS about when participants started to smoke or vape, or when they were first diagnosed with a disease. Absent this critical data, it is impossible to demonstrate that smoking or vaping preceded the disease, and therefore had any role in causing it.

While authors of some of the studies tried to use a statistical sleight of hand by claiming that their results were “adjusted” for smoking, that is not a legitimate work-around for the missing cause-and-effect information.

Some studies used PATH data, which does contain all of the information needed to analyze whether smoking and vaping preceded the diseases and therefore might have caused them.  Readers of my blog know that my research group in 2019 used PATH data to demonstrate that a heart attack study published in the flagship journal of the American Heart Association was pure fiction, resulting in its retraction by journal editors.  Now we have analyzed PATH data to demonstrate that none of the vaping-caused-disease claims in the recent studies are valid.

Our design was simple: We started by determining at what age participants were diagnosed with smoking-attributable diseases – chronic obstructive pulmonary disease (COPD), emphysema, myocardial infarction (MI, or heart attack) and stroke.  We then noted when participants started smoking or vaping.  The results were crystal clear.  As we reported in our study, “Only 4% of COPD and emphysema cases, 6% of MIs and 11% of stroke had occurred in PATH participants who had used e-cigarettes prior to the diagnoses. In contrast, over 94% of all cases occurred after smoking cigarettes fairly regularly.” 

In summary, the cited studies’ claims that vaping is related to or causes airway and circulatory diseases are not valid, as the authors lacked or ignored causative pathway information.  As for those few cases in which vaping preceded the disease, we note in our article, this may indicate “a potential reverse association between e-cigarette use and these diseases. In other words, having a diagnosis for respiratory and cardiovascular diseases leads smokers to use e-cigarettes.”

 

   Deficient and Unreliable Studies of Vaping and Disease

   Alzahrani T, Pena I, Temesgen N, Glantz SA (2018).  Association between electronic cigarette use and myocardial infarction.  Am J Prev Med 55(4):455-461. https://pubmed.ncbi.nlm.nih.gov/30166079/   

Vindhyal MR, Okut H, Ablah E, Ndunda PM, Kallail KJ, Choi WS (2020).  Cardiovascular outcomes associated with adult electronic cigarette use.  Cureus 12(8): e9618.  https://pubmed.ncbi.nlm.nih.gov/32923219/ 

Wills TA, Pagano I, Williams RJ, Tam EK (2019).  E-cigarette use and respiratory disorder in an adult sample.  Drug Alc Depend 194:363-370.  https://doi.org/10.1016/j.drugalcdep.2018.10.004 

Osei AD, Mirbolouk M, Orimoloye OA, et al (2019).  Association between e-cigarette use and cardiovascular disease among never and current combustible-cigarette smokers.  Am J Med 132:949-954.  https://doi.org/10.1016/j.amjmed.2019.02.016 

Parekh T, Pemmasani S, Desai R (2020).  Risk of stroke with e-cigarette and combustible cigarette use in young adults.  Am J Prev Med 58(3):446-452.

   Bircan E, Bezirhan U, Porter A, Fagan P, Orloff MS (2021).  Electronic cigarette use and its association with asthma, chronic obstructive pulmonary disease (COPD) and asthma-COPD overlap syndrome among never cigarette smokers.  Tob Ind Dis 19:23. https://doi.org/10.18332/tid/132833 

   Wills TA, Choi K, Pokhrel P, Pagano I (2022).  Tests for confounding with cigarette smoking in the association of e-cigarette use with respiratory disorder: 2020 national-sample data. Prev Med  https://doi.org/10.1016/j.ypmed.2022.107137

Perez MF, Atuegwu N, Mead E, Oncken C, Mortensen EM (2018).  E-cigarette use is associated with emphysema, chronic bronchitis and COPD.  Am J Respir Crit Care Med 197:A6245.  

Zhang Z, Jiao Z, Blaha MJ, et al (2022).  The association between e-cigarette use and prediabetes: results from the Behavioral Risk Factor Surveillance System, 2016-2018.  Am J Prev Med 62(6):872-877.  https://doi.org/10.1016/j.amepre.2021.12.009 

Atuegwu NC, Perez MF, Oncken C, Mead EL, Maheshwari N, Mortensen EM (2019).  E-cigarette use is associated with a self-reported diagnosis of prediabetes in never cigarette smokers: results from the Behavioral Risk Factor Surveillance System Survey.  Drug Alc Depend 205: 107692. doi:10.1016/j.drugalcdep.2019.10769

Miller CR, Shi H, Li D, Goniewicz ML (2021).  Cross-sectional associations of smoking and e-cigarette use with self-reported diagnosed hypertension: findings from Wave 3 of the Population Assessment of Tobacco and Health Study.  Toxics 9:52 https://doi.org/10.3390/toxics9030052 

Osei AD, Mirbolouk M, Orimoloye OA et al. Association between e-cigarette use and chronic obstructive pulmonary disease by smoking status: Behavioral Risk Factor Surveillance System 2016 and 2017.  Am J Prev Med 58, ISSUE 3, P336-342, March 01, 2020.  https://doi.org/10.1016/j.amepre.2019.10.014  

Osei AD, Mirbolouk M, Orimoloye, OA et al. The association between e-cigarette use and asthma among never combustible cigarette smokers: Behavioral Risk Factor Surveillance System (BRFSS) 2016 & 2017. BMC Pulm Med 19, 180 (2019). https://doi.org/10.1186/s12890-019-0950-3

Smoking May Harm Mental Health

Research has documented a strong link between smoking and various mental health disorders, including anxiety, depression, schizophrenia and bipolar disorder.  The CDC advises that about 20% of American adults had some form of mental illness in 2009-2011, and the smoking rate for that group was 36%, in contrast to 21% for all others (here).

There is certainly an association, but there are four distinct possibilities with respect to causality:

·       Mental health problems cause people to smoke.

·       Smoking causes mental health problems.

·       Both pathways exist.

·       Neither pathway exists.

My economist colleague Dr. Nantaporn Plurphanswat is the lead author of an innovative analysis that identifies a potential causal pathway for mental illness and smoking; the work appears in the American Journal of Health Behavior (abstract here).  Our co-author is University of Illinois professor Dr. Robert Kaestner.  We used data from people in almost all states participating in the federal Behavioral Risk Factor Surveillance System (BRFSS) from 2000 to 2010.  BRFSS collected information on smoking and asked participants “…for how many days during the past 30 days was your mental health [which includes stress, depression, and problems with emotions] not good?”

Recognizing that traditional approaches cannot identify a causal pathway between smoking and mental illness, Drs. Plurphanswat and Kaestner employed an instrumental variable approach, in which variation in smoking at the state level is strongly associated with cigarette excise taxes, but the excise taxes are completely unrelated to outcomes like mental health.  The IV analysis provides information on whether smoking leads to mental health problems, or vice versa.

Our results indicate that smoking may harm mental health: it is significantly associated with 14 or more days of poor mental health.  Most of the effect due to smoking is from large increases in the number of mentally unhealthy days and not by small increases among many smokers. 

The BRFSS data cannot tell us whether smoking is a form of self-medication practiced by those who suffer from specific mental health disorders.  However, our analysis confirms that smoking may contribute to anxiety, depression and emotional distress.  Thus, policies that reduce smoking may have a positive spill-over effect in improving mental health.

  

The CDC: Your Online Source for Incredible Tobacco Information

The U.S. government is battling tobacco and tobacco users, based to a great extent on misinformation promulgated by the Centers for Disease Control and Prevention (CDC). The CDC bills itself as “Your Online Source for Credible Health Information,” but two recent reports clearly demonstrate that the agency is deliberately deceiving Americans about fundamental facts concerning tobacco use.

Last week, the CDC published an article in the Morbidity and Mortality Weekly Report (MMWR) about the dual use of smokeless tobacco and cigarettes among men and women in the U.S. (available here). The data was from the 2009 Behavioral Risk Factor Surveillance System (BRFSS), an on-going telephone health survey tracking U.S. health conditions and risk behaviors yearly since 1984.

The information in the CDC report was routine: Smokeless tobacco use was highest in Wyoming and West Virginia (9 percent), and lowest in California (1 percent). Smoking rates were highest in Kentucky, West Virginia and Oklahoma (about 26 percent), and lowest in Utah (10 percent), California (13 percent) and Washington (15 percent).

Still, CDC director Dr. Tom Frieden used the results to rejoin the attack, with a special focus on smokeless products: “Tobacco use is the leading preventable cause of death in this country and unfortunately smokers are also using smokeless tobacco. If you smoke, quitting is the single most important thing you can do to improve your health. Use of smokeless tobacco may keep some people from quitting tobacco altogether. We need to intensify our anti-tobacco efforts to help people quit using all forms of tobacco.”

This week, with the help of the Wall Street Journal (here), the CDC turned its attention back to cigarettes, with the claim that smoking rates stopped declining several years ago. Here’s the lead:

“Many cash-strapped U.S. states are slashing budgets for tobacco-prevention programs, raising alarms among public-health groups as the nation's progress toward getting adult smokers to quit has stalled. The adult smoking rate was 20.6% in 2009, the same as a year earlier and largely unchanged since 2004, according to the Centers for Disease Control and Prevention.”

The basis for these numbers was the 2009 National Health Interview Survey (NHIS)(available here), which reported that the prevalence of smoking has been “largely unchanged” for the past several years, at just above 20%. But what about the BRFSS (discussed above)? What does that survey say about smoking rates?

For 2004, BRFSS reported the prevalence of current smoking as 20.9%, about the same as the NHIS. But for 2009, according to BRFSS, smoking prevalence had dropped to 17.9%. That’s a whopping decline of 14% in just 5 years!

One year ago I discussed in this blog how different federal surveys report contrasting data on smoking in the U.S. (here). We now have a brilliant example of how the CDC creates a consistent anti-tobacco narrative by cherry-picking data from what are essentially conflicting datasets. The public, and government budgeting officials, would be better served by a CDC that focused on reporting and explaining the unvarnished facts, free of any social behavioral bias.