2 days, 2 new articles calling into the conclusion of a 2024 meta-analysis and systematic review on apparent health effects associated w/ e-cigarette use.

Lessons for how to analyze to reduce bias & confounding 🧵👇 2) Background:

Original systematic review by Glantz et al. examined a variety of health outcomes in relation to e-cig use and dual use, concluding:

evidence.nejm.org/doi/10.1056/EV…

Mini 🧵on recent literature showing the importance of flavored e-cigs

1) Secondary analysis of last year's Auer et al. RCT, where flavor choice was up to participants.

Fruit flavors were more common among those who stopped smoking:

doi.org/10.18332/tpc/1… 2) Secondary analysis of the Wagoner et al. 2023 RCT (which also allowed choice of flavors) showed:

- Only 5% used only tobacco flavor
- Those who used non-tobacco flavors were more likely to continue using e-cigs, reduce cig consump, and (maybe) switch:

doi.org/10.1016/j.addb…

🚨 1) My new commentary with Martino Ruggieri & @RiccardoPolosa at @CoeharUnict on different definitions of youth e-cig use, evaluating pros and cons of each and making rec's.

frontiersin.org/journals/publi…
2) See disclosures in image below, but this paper reflects our own opinions and was not supported or overseen by our funders.

Master🧵of all my 's 🧵on THR science.

Most (but not all) are my own studies.

Disclosures: Through Pinney Associates, I consult for JUUL. I also consult for CoEHAR which rec'd funding from FSFW (now Global Action to End Smoking). My prior academic research motivated this shift. 2) Gateway commentary, on evidence and alternative explanations of the e-cig gateway hypothesis:

https://twitter.com/ArielleSelya/status/1799176202990850552

1) 🚨 My new commentary on the gateway hypothesis (GH) is now published.

The paper is aimed at a lay audience to explain the evidence for and against GH.

Stay to the end & I'll ask your thoughts!

Full text here: link.springer.com/article/10.118…
2) Evidence for GH is based on individual-level survey data showing that youth who use e-cigs are more likely to also smoke cigarettes.

Strengths: this happens with the right time sequence (e-cigs first, then cigs), and has plausible mechanisms (e.g., becoming nic-dependent).

1) What happens when a less-harmful alternative nicotine product (ANP) displaces tobacco smoking in a population?

We can learn a lot from the case of snus in Norway, as I just presented at #SRNT2024 as a personal side project with @LundKarl

osf.io/preprints/osf/…
2) There are concerns about ANP uptake by smoking-naïve individuals (both for snus back then, and for e-cigs now).

Uptake by smoking-naive folks CAN be a bad thing if it's adding to smoking, but in many countries, smoking is declining faster than ever.

What gives?🤔

1/15 “Gateway” fears about e-cigarette use leading to cigarette smoking are a major justification for restrictive policies on e-cigarettes. But what does the actual evidence say about “gateway”? 2/15 First off, there is undoubtedly an *association* between e-cigarette use and cigarette smoking among youth. But does this mean e-cigarette use CAUSED these youth to smoke?

1/15: My new paper in Harm Reduction Journal simulates what the US situation might look like if we promote e-cigarettes as a harm reduction policy: rdcu.be/cg94K . Hint: #VapingSavesLives 2/15: In system dynamics modeling, it’s important to focus on a specific, measurable problem to solve. Here, it’s the combustible tobacco-related death burden (~480,000 lives/year).

1/14 How do e-cigarettes (ECs) affect cigarette smoking among youth? My new paper with @FloeFoxon simulates each scenario and finds out which one best matches actual trends... onlinelibrary.wiley.com/doi/abs/10.111… @jgitchell @mikepesko @SwitchFinder @jkelovuori @TobPolicy @Clive_Bates 2/14 First, let's talk about why this question is so difficult to answer: COUNTERFACTUALS. We can't know the alternate-reality answers, like which smokers would have never started in a world without ECs, and which nonsmokers would now be smoking without ECs as an option.