Safety of e-cigarettes and nicotine patches as stop-smoking aids in pregnancy: Secondary analysis of the Pregnancy Trial of E-cigarettes and Patches (PREP) randomised controlled trial

Pesola, Francesca; Smith, Katie Myers; Phillips-Waller, Anna; Przulj, Dunja; Griffiths, Christopher; Walton, Robert; Mcrobbie, Hayden; Coleman, Tim; Lewis, Sarah; Whitemore, Rachel; Clark, Miranda; Ussher, Michael; Sinclair, Lesley; Seager, Emily; Cooper, Sue; Bauld, Linda; Naughton, Felix; Sasieni, Peter; Manyonda, Isaac; Hajek, Peter

Abstract

Aims

To examine safety of e-cigarettes (EC) and nicotine patches (NRT) when used to help pregnant smokers quit.

Design

A recent trial of EC versus NRT reported safety outcomes in the randomised arms. We conducted a further analysis based on product use.

Setting

23 hospitals in England and a stop-smoking service in Scotland. Participants 1,140 pregnant smokers.

Interventions:

We compared women using and not using EC and NRT regularly during pregnancy.

Measurements:

Nicotine intake compared with baseline, birth weight, other pregnancy outcomes, adverse events, maternal respiratory symptoms, relapse in early abstainers.

Findings:

Use of EC was more common than use of NRT (47% vs 21%, p<0.001). Women who stopped smoking (abstainers) and used EC at the end-of-pregnancy (EOP) reduced their salivary cotinine by 45% (49.3ng/ml, 95% confidence interval [CI]: -79.8 to -10). Only one abstainer used NRT at EOP. In dual users, cotinine increased by 19% (24ng/ml, 95%CI: 3.5 to 58.0). In women reporting a reduction of at least 50% in cigarette consumption, cotinine levels increased by 10% in those using nicotine products and by 9% in those who did not. Birthweights in dual-users and exclusive smokers were the same (3.1kg). Birthweight in abstainers using either nicotine product was higher than in smokers (3.3 kg (standard deviation [SD]=0.7) vs 3.1 kg (SD=0.6); difference=0.15 kg, 95%CI: 0.05 to 0.25) and not different from abstainers not using nicotine products (3.1 kg (SD=0.8)). Abstainers and smokers using nicotine products had no worse pregnancy outcomes or more adverse events than abstainers and smokers not using them. EC users reported more improvements than non-users in cough (adjusted relative risk=0.59, 95%CI:0.37 to 0.93) and phlegm (aRR=0.53, 95%CI:0.31 to 0.92), controlling for smoking status. EC or NRT use had no association with relapse.

Conclusions:

Regular use of e-cigarettes or nicotine patches by pregnant smokers does not appear to be associated with any adverse outcomes

Citation

Pesola, F., Smith, K. M., Phillips-Waller, A., Przulj, D., Griffiths, C., Walton, R., Mcrobbie, H., Coleman, T., Lewis, S., Whitemore, R., Clark, M., Ussher, M., Sinclair, L., Seager, E., Cooper, S., Bauld, L., Naughton, F., Sasieni, P., Manyonda, I., & Hajek, P. (2024). Safety of e-cigarettes and nicotine patches as stop-smoking aids in pregnancy: Secondary analysis of the Pregnancy Trial of E-cigarettes and Patches (PREP) randomised controlled trial. Addiction, 119(5), 875-884. https://doi.org/10.1111/add.16422

• Journal Article Type: Article
• Acceptance Date: Nov 29, 2023
• Online Publication Date: Jan 17, 2024
• Publication Date: 2024-05
• Deposit Date: Dec 11, 2023
• Publicly Available Date: Jan 18, 2025
• Journal: Addiction
• Print ISSN: 0965-2140
• Electronic ISSN: 1360-0443
• Publisher: Wiley
• Peer Reviewed: Peer Reviewed
• Volume: 119
• Issue: 5
• Pages: 875-884
• DOI: https://doi.org/10.1111/add.16422
• Public URL: https://nottingham-repository.worktribe.com/output/28419474
• Publisher URL: https://onlinelibrary.wiley.com/doi/10.1111/add.16422