The impact of COVID-19 on smoking cessation in pregnancy

Introduction

A greater number of smokers attempted to stop smoking during the COVID-19 pandemic [1]. Available UK data for pregnant women, however, suggested only a small decrease in smoking rates, falling from a mean of 10.42% in 2019 to 9.75% in the first half of 2020 [2]. To reduce the rates of smoking in pregnancy, all pregnant smokers should be referred to antenatal smoking cessation services [3]. Those clinics provide detailed cessation advice and, in line with current National Institute for Clinical Excellence (NICE) guidelines, can recommend behavioural interventions, such as cognitive behavioural therapy and motivational interviewing, as first line interventions to help women stop smoking [3]. If those methods are unsuccessful, NICE guidance advises the use of pharmacological nicotine replacement therapies (NRT) [3]. From March 2020 smoking cessation services continued their clinics virtually due to the COVID-19 pandemic.

Despite increased attempts to stop smoking during the pandemic, no increase in uptake of smoking cessation support, including NRT use, was observed amongst non-pregnant adults [1]. The impact of the COVID-19 pandemic on the demand for antenatal smoking cessation services, however, has not been considered. We, therefore, audited the use of a community antenatal smoking cessation service and uptake of nicotine replacement therapies in pregnant women, before and during the COVID-19 pandemic.

Materials and methods

Anonymized data from pregnant women attending the Lambeth and Southwark community specialist smoking cessation service from the 1st of April 2019 to March 31st, 2021 were reviewed. These data included demographic information, medical history, cigarette smoking habits, the smoking cessation strategies utilised and the success of those strategies. The impact of the COVID-19 pandemic was considered by comparing data from 2019–2020 to data from 2020–2021. This audit was approved by the local Trust Clinical Governance and Audit department.

Results

A total of 252 pregnant women who smoked were referred to their local antenatal smoking cessation service, of which 90 (35.7%) (median age: 31 years [19–52 years]) chose to attend smoking cessation clinics. The COVID-19 pandemic was not associated with an increase in the number of women attending smoking cessation clinics (2020–2021 n=46 of 110 [40.8%] compared to pre-pandemic 2019–2020 n=44 of 142 [30.9%] referred pregnant women) (p=0.061). Eighteen (20%) women had a history of mental health problems. The number of women disclosing mental health problems did not increase in the COVID-19 pandemic (2019–2020 n=9, 2020–2021 n=9). Other medical co-morbidities included asthma (n=7, 7.8%), dermatological conditions (n=3, 3.3%) and cancer (n=1, 1.1%).

Prior to smoking cessation, 30% of women (2019–2020 n=14, 2020–2021 n=12) reported smoking 11 cigarettes or less, and 26.7% of women smoked 11 to 20 cigarettes per day (2019–2020 n=11, 2020–2021 n=13). Thirty women (33.3%) exclusively utilised cigarettes, whilst 14 (15.6%) used roll-ups, and 6 (6.7%) women used both. One woman reported only using chewing tobacco, 39 women did not quantify their smoking habits (2019–2020 n=19, 2020–2021 n=20).

Most women (n=59, 65.6%) had the date on which they stopped smoking as well as the due date for their pregnancy recorded. Women stopped smoking a median of 127 days (range: 18–274 days) into their pregnancy in the 2019–2020 cohort. Similarly, women stopped smoking a median of 124 days (43–237 days) during the COVID-19 pandemic. When comparing cessation dates before and during the pandemic, there was no significant difference (p=0.235) in the number of women trying to stop smoking before 20 weeks of gestation (Figure 1).

Figure 1:

Comparison of smoking cessation dates in context of pregnancy duration before and during the COVID-19 pandemic.

To help them stop smoking, 82 women (91.1%) utilised NRT, whilst 8 did not. There was no significant difference (p=0.420) in the frequency of NRT use before and during the COVID-19 pandemic (2019–2020 n=39, 2020–2021 n=43). NRT was provided in multiple different formats, including a nicotine patch, nicotine inhalators, mouth sprays, chewing gums or lozenges. Fifty-eight (64.4%) women utilised more than one type of NRT throughout their pregnancy and 19 (21.1%) utilised more than two different types. The most frequently utilised NRT format was the nicotine patch (n=71, 78.8%), followed by mouth spray (n=38, 42.2%), nicotine inhaler (n=27, 30%), chewing gum (n=19, 21.1%) and lozenges (n=12, 13.3%). The popularity of different NRT formats did not change due to the COVID-19 pandemic (Figure 2).

Figure 2:

Frequency of use of varying nicotine-replacement therapies.

When considering the impact of the COVID-19 pandemic on smoking cessation rates (Table 1), there was no significant difference in the rates of abstinence at either four-week (p=0.285) or twelve-week follow-up (p=0.829) (Table 1).

Discussion

Our results demonstrate that during the COVID-19 pandemic there were no significant changes in smoking cessation rates in pregnancy or the demand for antenatal smoking cessation services. Rates of NRT use also remained unchanged. A recent study of smoking cessation in non-pregnant adults, similarly, demonstrated no increased uptake of formal smoking cessation support or the use of NRT during the COVID-19 pandemic [1]. Smoking cessation rates, however, remained unaffected by the COVID-19 pandemic in our cohort of pregnant women, whereas greater attempts to stop smoking were observed in non-pregnant adults [1]. As such, other factors may be exerting a greater influence on smoking cessation in pregnancy independent from the COVID-19 pandemic. For instance, mental health diagnoses are well-recognised confounding factors that may hinder pregnant women from giving up smoking [4] and were the most frequent co-morbidity observed in our cohort of women, both before and during the COVID-19 pandemic. Similar levels of did not attend rates were seen pre and during the pandemic

Recent studies have demonstrated widespread non-adherence to smoking cessation therapies in large cohorts of pregnant women [5]. As the majority of women were utilising NRT, the unchanged smoking cessation rates may reflect a lack of effectiveness of NRT. Indeed, hepatic nicotine metabolism is increased in pregnancy, potentially explaining the need for women to utilise different types of NRT with varying onsets of action [6]. Our data may reflect insufficient use of higher dose levels of NRT rather than ineffectiveness of NRT.

In conclusion, our data demonstrate that smoking cessation rates in pregnant women and the demand for antenatal smoking cessation services remained unchanged during the COVID-19 pandemic, thereby differing from the trends observed in the general adult population during the COVID-19 pandemic.