Comparison of saliva cotinine and exhaled carbon monoxide concentrations when smoking and after being offered dual nicotine replacement therapy in pregnancy.
Bhavandeep Slaich, Ravinder Claire, Joanne Emery, Sarah Lewis, Sue Cooper, Ross Thomson, Lucy Phillips, Darren Kinahan-Goodwin, Felix Naughton, Lisa McDaid, Miranda Clark, Anne Dickinson, Tim Coleman
Author Information
Bhavandeep Slaich: Division of Primary Care, University of Nottingham, Nottingham, UK. ORCID
Ravinder Claire: Division of Primary Care, University of Nottingham, Nottingham, UK. ORCID
Joanne Emery: School of Health Sciences, University of East Anglia, Norwich, UK.
Sarah Lewis: Division of Epidemiology and Public Health, University of Nottingham, Nottingham, UK.
Sue Cooper: Division of Primary Care, University of Nottingham, Nottingham, UK.
Ross Thomson: Division of Primary Care, University of Nottingham, Nottingham, UK.
Lucy Phillips: Division of Primary Care, University of Nottingham, Nottingham, UK.
Darren Kinahan-Goodwin: Division of Primary Care, University of Nottingham, Nottingham, UK.
Felix Naughton: School of Health Sciences, University of East Anglia, Norwich, UK. ORCID
Lisa McDaid: School of Health Sciences, University of East Anglia, Norwich, UK.
Miranda Clark: Division of Primary Care, University of Nottingham, Nottingham, UK. ORCID
Anne Dickinson: Division of Primary Care, University of Nottingham, Nottingham, UK.
Tim Coleman: Division of Primary Care, University of Nottingham, Nottingham, UK. ORCID
BACKGROUND AND AIMS: Although English Stop smoking Services routinely offer dual nicotine replacement therapy (NRT) to help pregnant women to quit smoking, little is known about how nicotine and tobacco smoke exposures following this compare with that from smoking. We compared, in pregnant women when smoking and after being offered dual NRT, saliva cotinine and exhaled carbon monoxide (CO) concentrations and numbers of daily cigarettes smoked. DESIGN AND SETTING: Secondary analysis of data from three sequential, observational, mixed-methods cohort studies conducted as part of the nicotine Replacement Effectiveness and Delivery in Pregnancy programme. Participants were recruited on-line or in Nottingham University Hospitals (UK) antenatal clinics between June 2019 and September 2020. PARTICIPANTS: Forty pregnant women, who agreed to try stopping smoking. INTERVENTION: Participants were offered dual NRT, agreed a smoking quit date and received an intervention to improve adherence to NRT. MEASUREMENTS: Saliva cotinine and exhaled CO concentrations and reported number of cigarettes smoked per day. FINDINGS: There were no differences in saliva cotinine concentrations at baseline and day 7 post quit date [n = 20, mean difference = -32.31 ng/ml, 95% confidence interval (CI) = -68.11 to 3.5 ng/ml; P = 0.074, Bayes factor = 0.04]. There were reductions in the reported number of cigarettes smoked per day (n = 26, mean difference = -7 cigarettes, 95% CI = -8.35 to -5.42 cigarettes, P < 0.001) and concurrently in exhaled CO concentrations (n = 17, ratio of geometric means = 0.30 p.p.m., 95% CI = 0.17-0.52 p.p.m.; P < 0.001). CONCLUSION: Pregnant women who smoke and are offered dual nicotine replacement therapy (NRT) appear to show no change in their exposure to cotinine compared with their pre-NRT exposure levels but they report smoking fewer cigarettes, as validated by reductions in exhaled carbon monoxide concentrations.
