Abstract
Background:Smoking tobacco cigarettes is a major risk factor for cancer, chronic obstructive pulmonary disease (COPD), stroke, and heart disease. Although the United Kingdom (UK) has a comprehensive tobacco control strategy and adult smoking prevalence has reduced considerably over the past decades, from 45% in 1974 to 12.9% in 2022, smoking is still a leading preventable cause of illness and premature death in the UK and worldwide. Additionally, there are significant disparities in smoking prevalence within the population. For example, smoking prevalence is significantly higher in those with mental health conditions compared to those without, and depression and anxiety are two of the most common mental health conditions among people who smoke. Research is needed to explore how further reductions in population-level smoking prevalence can be made, including in those with mental health conditions, in order to reach national “smoke-free” or “tobacco end game” ambitions for all, which are typically defined as ≤5% adult smoking prevalence.
Aim and Objectives:
Aim: Contribute to the evidence base regarding how the provision and uptake of smoking cessation support options (including nicotine vaping products [NVPs]) could be improved.
Objective 1: Review the evidence for the effectiveness of interventions (implementation strategies), which were implemented on a national or state-wide scale, aiming to increase the provision of smoking cessation treatment in primary care.
Objective 2: Describe and characterise the extent to which NVP use has been recorded in primary care electronic health records in the UK.
Objective 3: Examine interactions between health professionals and people who smoke with and without common mental health conditions (depression and/or anxiety), about smoking cessation and nicotine vaping products.
Objective 4: Assess cessation aid utilisation by people who smoke with and without common mental health conditions (depression and/or anxiety) used in their last attempt to quit smoking.
Methods:
To achieve the four objectives, four studies were conducted.
Study 1: Systematic review and narrative synthesis of findings.
Study 2: Exploratory analysis of Clinical Practice Research Datalink (CPRD), 2006–2022: electronic primary care patient data from ~25% of the UK population.
Study 3: Using 2018 cross-sectional International Tobacco Control Four Country Smoking and Vaping Survey data from Australia, Canada, England and the United States (US), weighted logistic regression models examined the association between self-reported current diagnosis/treatment for depression and/or anxiety and health professional interactions about smoking cessation and nicotine vaping (visiting a HP; receiving advice to quit smoking from a HP; discussing NVPs with a HP; receiving a positive recommendation to use NVPs).
Study 4: Using the same survey data as in Study 3, weighted logistic regression models examined the association between self-reported current diagnosis/treatment for depression and/or anxiety and what cessation support option (any cessation support, nicotine replacement therapy [NRT], varenicline or bupropion, behavioural support, or NVPs) was used at last smoking quit attempt.
Results:
Study 1: The systematic review identified 49 studies. Implementation strategies which involved ‘changing infrastructure’, ‘training and educating stakeholders’, and ‘engaging consumers’ increased smoking status recording and cessation advice provision in primary care. Implementation strategies which involved ‘utilizing financial strategies’ increased smoking status recording and cessation advice provision, and smoking cessation. Implementation strategies which involved ‘training and educating stakeholders’ increased smoking status recording and cessation advice provision, and smoking cessation, but the evidence was low-quality.
Study 2: Using UK primary care data, I identified seven medical codes indicating current or former vaping. Vaping documentation was very low: 150,144 unique patients out of the estimated ~16 million patients registered in CPRD had ever received a vaping medical code. The first incidence of vaping documentation was in October 2011; vaping code incidence increased from September 2013. The ‘e-cigarette or vaping product use-associated lung injury’ (EVALI) outbreak in the US (and peak media coverage in September 2019) was significantly associated with a reduction in new records of current vaping, manifested as a declining trend over a period of seven months (September 2019 to March 2020); additionally, there was an immediate increase in new records of former vaping, followed by a declining trend over the subsequent seven-month period. When patients received their first vaping code, mean age was 50.2 years, 52.4% were female, and 82.1% were White. When receiving the first vaping code, the majority of patients were either smoking or had quit smoking in the past, and <2% were recorded as having never smoked. Of those recorded as currently vaping, 98.9% had records of their previous smoking status, and 55.0% had records of their smoking status over a period greater than 12 months. Over a year after being recorded as vaping, 34.2% of people who were smoking prior to being recorded as vaping were still smoking, 23.7% quit smoking, 1.7% received a ‘never smoked’ status, and there was no smoking status for 40.4%.
Study 3: People with anxiety and/or depression who smoke were more likely to visit a HP than those without, but only those with depression were more likely to receive cessation advice. Among those who had visited their HP, less than half (47.9%) reported receiving advice to quit smoking. Those with both depression and anxiety were more likely to discuss NVPs, compared to those without depression/anxiety. The likelihood of receiving a positive recommendation to use NVPs did not differ by mental health condition. NVP discussions and receiving a positive recommendation to use them were rare overall.
Study 4: A large proportion (40%) of respondents did not use any cessation aid in their last quit attempt and there was a high rate of unsuccessful quit attempts: 76%. At their last smoking quit attempt, those with anxiety, and both anxiety and depression were more likely to use any cessation support than those without these mental health conditions. Specifically, those with depression and anxiety were more likely to use NRT, and those with depression and/or anxiety were more likely to use behavioural support, compared to those without depression/anxiety. However, the use of NVPs and varenicline/bupropion to quit smoking was similar among adults with and without depression/anxiety.
Conclusions:
The rate at which health professionals deliver smoking cessation advice and support is suboptimal. I found evidence towards the effectiveness of utilizing financial strategies, and some (limited) evidence towards training and educating stakeholders, on increasing smoking cessation rates. I recommend that health professionals conduct continued professional development/training to ensure that they are up to date with the smoking cessation support options that are available, and the guidance regarding their use. I recommend that cessation support options be made available to people who smoke free of charge. Also, while not all the evidence is certain for all forms of provider incentivisation, I did find some evidence that they may increase cessation rates. I recommend that future implementation strategies attempt to better align with the existing technologies and the routine systems in place. In future research, researchers could explore if there are any ways to optimise Very Brief Advice (VBA) further, and I advise that studies assess the effectiveness of implementation strategies on both (practitioner-level) provider performance as well as (patient-level) smoking outcomes.
I found that the documentation of vaping in UK primary care was low but increasing over time. Given that population-level electronic health records could be employed to investigate the long-term health effects and smoking cessation outcomes of vaping, I proposed recommendations to improve the completeness, accuracy and consistency of vaping status recording, by refining medical codes for vaping, and introducing a Quality and Outcomes Framework indicator for recording vaping status.
I found that there are missed opportunities for health professionals to provide cessation advice and recommendations about using NVPs to quit smoking, and to offer cessation support. Given that a large proportion of respondents did not use any cessation aid in their last quit attempt and there was a high rate of unsuccessful quit attempts, I advise that health professionals should systematically offer ongoing cessation support to all patients, regardless of mental health status. However, in order to address the disparity in smoking prevalence between those with and without mental health conditions, health professionals need to increase the rate of smoking cessation support provision to those who smoke and have mental health conditions (above the rate of provision to people who smoke without mental health conditions). As NVPs are potentially the most effective smoking cessation support option currently available, it is important that healthcare professionals provide accurate information about and access to NVPs to people who smoke, especially for individuals with mental health conditions. To achieve this, people with mental health conditions could be specifically targeted as a priority population in some of the policy recommendations recently made in the Khan review and the initiatives recently announced by the UK government, such as the national ‘swap to stop’ programme, where people who smoke will be able to switch cigarettes for NVPs.
| Date of Award | 1 Mar 2024 |
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| Original language | English |
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| Supervisor | Leonie Brose (Supervisor) & Ann McNeill (Supervisor) |