Double-blind, placebo randomised controlled trial of standard dose nicotine patches for smoking cessation in pregnancy: SNAP trial findings
Author(s)
Tim Coleman, Sue Cooper and Sarah Lewis
Presenter(s)
Professor Tim Coleman Professor in Primary Care, Division of Primary Care, UKCTCS, University of Nottingham
Abstract
Introduction
Nicotine replacement therapy (NRT) may not work in pregnancy because pregnant women metabolise nicotine and cotinine more quickly. This trial tested 15mg/16hr nicotine patches, added to behavioural support, for effectiveness and safety in pregnancy.
Methods
Participants were aged 16 to 50 years, between 12 and 24 weeks’ gestation and smoked > 5 daily cigarettes. All received behavioural cessation support and were randomised to eight weeks’ active or placebo patches. Further behavioural support was provided by research midwives and local NHS cessation service staff. The primary outcome was validated smoking cessation (by CO and / or saliva cotinine) between a quit date set after randomisation and delivery and birth outcomes were monitored.
Results
521 women received NRT (529 placebo). There was no difference in cessation between groups at delivery; rates were 9.4% (NRT) and 7.6% (placebo), respectively [odds ratio with NRT, 1.26; 95% CI, 0.82 to 1.96)]. However, at 1 month cessation was higher in the NRT group (21.3% vs. 11.7%). Only 7.2% of women given NRT used patches for more than 1 month (2.8% for placebo). Rates of adverse pregnancy and birth outcomes were similar.
Conclusions
Adding a 15mg/16hr nicotine patch to behavioural cessation support for pregnant women is not effective for smoking cessation and has neither a beneficial nor negative impact on birth outcomes.
Source of funding: NIHR Health Technology Programme
Declaration of interest: Tim has provided consultancy services on a number of occasions for drug companies which manufacture NRT (Pfizer, Johnson and Johnson, Pierre Fabre Laboratories). He has done this on four occasions during the past decade and NRT used in this trial was paid for by the NHS and was manufactured provided by a company that Tim has not done consultancy work for.
