Lion Shahab

University College London | UCL · Department of Behavioural Science and Health

Modeling trajectories in cigarette smoking prevalence, initiation and quitting for populations and subgroups of populations is important for policy planning and evaluation. This paper proposes an agent-based model (ABM) design for simulating the smoking behaviors of a population using the Capability, Opportunity, Motivation - Behavior (COM-B) model...

Background Vaping prevalence has increased rapidly in England since 2021. This study estimated trends between 2013 and 2024 in vaping among ex-smokers, overall and among those who did not use e-cigarettes to support their quit attempt. Methods Data were collected via nationally-representative, monthly cross-sectional surveys in England, October 20...

Introduction Thousands of patients with mental illness are admitted to acute adult mental health wards every year in England, where local guidance recommends that all mental health settings be entirely smokefree. Mental health trusts presently invest substantial effort and resources to implement smokefree policies and to deliver tobacco dependence...

Objectives There is evidence that general practitioners (GPs) can increase the uptake of weight management programmes that enhance weight loss compared with self-directed efforts, but the rate at which they do so is unclear. This study examined the prevalence of weight control efforts and practices, the reported frequency and impact of receipt of G...

Background This study aimed to characterise patterns of tobacco smoking and vaping among older adults (≥ 65 years) in England, to explore harm perceptions of e-cigarettes among those who smoke, and to estimate the real-world effectiveness of e-cigarettes for helping older adults to stop smoking. Methods Data were collected as part of a representat...

Introduction There is majority support in parliament and across the United Kingdom to implement a “smoke-free generation” policy which would mean people born on or after January 1, 2009, could never legally be sold tobacco. To explore the potential impact this policy could have, we estimated the number of young adults (18–25 years) currently taking...

Background Cigarette smoking is incredibly harmful, even for people who do not smoke every day. This study aimed to estimate trends in non-daily smoking in England between 2006 and 2024, how these differed across population subgroups, and to explore changes in the profile of non-daily smokers in terms of their sociodemographic and smoking character...

Introduction Studies consistently demonstrate smoking is a socially contagious behaviour, but less is known about the influence of social connections on vaping. This study examined associations between having close social connections who smoke or vape and relevant smoking and vaping outcomes. Methods This was a representative cross-sectional surve...

Background: Smoking rates in the UK have declined steadily over the past decades, masking considerable inequalities, as little change has been observed among people with a mental health condition. This trial sought to assess the feasibility and acceptability of supplying an electronic cigarette (e-cigarette) starter kit for smoking cessation as an...

Importance A wide range of medications, non-combustible nicotine products, behavioural support, and alternative treatments are available in England to help people stop smoking. Understanding their effectiveness in the real world can support informed decision-making. Objectives To provide up-to-date estimates of the prevalence and real-world effect...

Introduction The sale of factory-made cigarettes with menthol as a characterizing flavor has been prohibited in Great Britain since May 2020. However, menthol accessories like flavored filters for roll-your-own (RYO) tobacco can be sold legally, possibly undermining the policy. This study aimed to explore the association between RYO and menthol cig...

Background The burden of morbidity and mortality in England, is greater among priority groups such as those with lower income or routine and manual occupations. Using a microsimulation model, we estimate projected changes in smoking prevalence according to socio-economic position under selected policy scenarios that are relevant to ongoing policy i...

Background/Aims: E-cigarettes are frequently used by people who smoke. This study examined how the prevalence and patterns of smoking and vaping ('dual use') in England have changed as the vaping market has rapidly evolved. Design: Representative monthly cross-sectional survey, July 2016 to April 2024. Setting: England. Participants: 128,588 adults...

Background and Aims: Due to the COVID-19 pandemic, the survey mode of the Smoking and Alcohol Toolkit Study, a long-running repeat cross-sectional survey, had to change from face-to-face to telephone interviews. This study aimed to assess similarities and differences in sociodemographic, smoking, alternative nicotine and alcohol use estimates betwe...

Background: Vaping prevalence has increased rapidly in England since 2021. This study estimated trends between 2013 and 2024 in vaping among ex-smokers, overall and among those who did not use e-cigarettes to support their quit attempt. Methods: Data were collected via nationally-representative, monthly cross-sectional surveys in England, October-2...

Introduction The effectiveness of e-cigarettes for smoking cessation may differ by source of purchase. The changing influence of self-selection on purchase location caused by COVID-19 pandemic-related vape shop closures means we can examine the association between smoking abstinence e-cigarette use by purchase source and test for the moderation of...

Objective To examine trends in long term (>6 months) vaping among adults in England. Design Population based study. Setting England. Participants 179 725 adults (≥18 years) surveyed between October 2013 and October 2023. Main outcome measures Time trends in prevalence of long term vaping using logistic regression, overall and by vaping frequenc...

Objectives This study explores the association between vaccine hesitancy, vaccine knowledge and psychological well-being with (1) receipt of/willingness to receive an initial vaccine against COVID-19, and (2) willingness to get vaccinated yearly against COVID-19. The importance of different vaccine attributes (eg, vaccine technology, effectiveness,...

Background There is majority support in parliament and across the United Kingdom (UK) to implement a ‘smokefree generation’ policy which would increase the legal age of sale of tobacco from 18 by one year each year from 2027 onwards, such that people born on or after 1 January 2009 could never legally be sold tobacco. To explore the potential impac...

Background and aims In March 2024, the UK government announced plans to introduce a Vaping Products Duty that will tax e‐liquids based on their nicotine strength. This study examined trends in the nicotine strength of e‐liquids used by adult vapers and differences in those currently used across relevant subgroups. Design Nationally‐representative,...

Background In the UK in May 2016, standardised packaging of tobacco products was implemented, including minimum pack sizes of 20 sticks or 30 g loose tobacco. The change was intended to reduce uptake by increasing upfront costs to young people, but there was concern it may unintentionally increase consumption among people smoking. This study aimed...

Objective To examine whether the real-world effectiveness of popular smoking cessation aids differs between users with and without a history of mental health conditions. Design Nationally-representative cross-sectional survey conducted monthly between 2016–17 and 2020–23. Setting England. Participants 5,593 adults (2,524 with a history of ≥1 men...

Introduction This study aimed to estimate time trends in cigarette consumption among smokers in England between 2008 and 2023 and to explore differences by key potential moderators. Aims and Methods We used data from 57 778 adult cigarette smokers participating in a nationally representative monthly cross-sectional survey between January 2008 and...

Background There has been a rapid rise in disposable (single-use) e-cigarette vaping among young adults in England since June 2021 (leading to a planned ban on these products). We examined how this has affected population trends in current (i) vaping, (ii) tobacco smoking, and (iii) inhaled nicotine use. Methods We used data from a nationally-repr...

Background and aims Varenicline is one of the most effective smoking cessation treatments. Its supply in England was disrupted in July 2021 due to nitrosamine impurities found by its supplier, Pfizer. This study measured the impact of this disruption on smoking cessation in England. Design, setting and participants The study used repeated cross‐se...

Background Tobacco smoking affects women’s fertility and is associated with substantial risks of adverse pregnancy outcomes. This study explored trends by socioeconomic position in patterns of smoking, use of non-combustible nicotine products, and quitting activity among women of reproductive age in England. Methods Data come from a nationally rep...

Background Increasingly, people smoke cigarettes outdoors and avoid exposing bystanders to harm. People may not have the same motivation to vape outdoors since e-cigarettes, unlike cigarettes, do not create side stream emissions and exhaled aerosol contains fewer toxicants than secondhand smoke. This study aims to estimate the prevalence and correl...

Objectives This study assessed public support for four proposed tobacco control policies in Great Britain: (1) Raising the sales age of tobacco by 1 year every year (Smokefree Generation); (2) Raising the sales age of tobacco from 18 years to 21 years; (3) Providing prescription e-cigarettes as smoking cessation aids to adults who smoke; (4) Restri...

Objectives Gambling is associated with cigarette smoking and alcohol consumption. We explored the intersection of gambling across all risk levels of harm with smoking and alcohol use among adults in Great Britain. Design A nationally representative cross-sectional survey in October 2022. Setting Great Britain. Participants A weighted total of 23...

Background/Aims: In March-2024, the UK government announced plans to introduce a new Vaping Products Duty that will tax e-liquids based on their nicotine strength. This study examined trends in the nicotine strength of e-liquids used by adult vapers and differences in those currently used across relevant subgroups. Design: Nationally-representative...

Background Menthol cigarettes have been banned in Great Britain (GB) since May 2020. Still, menthol accessories and unlabelled cigarettes perceived as mentholated are available, and people can buy menthol cigarettes overseas or illicitly. This study assessed: trends in smoking menthol cigarettes among all adults and 18–24-year-olds in GB between Oc...

Introduction The UK Government intends to implement a “smokefree generation” policy prohibiting the sale of all tobacco products to people born after 2008. National surveys provide comprehensive data on cigarette smoking, but little is known about patterns of non-cigarette tobacco smoking across key population groups. Aims and Methods Using data f...

Importance Electronic cigarettes (e-cigarettes) are less harmful to users than combustible cigarettes. However, public health and media reporting have often overstated the potential risks of e-cigarettes, and inaccurate perceptions of the harms of vaping relative to smoking are pervasive. Objective To examine time trends in harm perceptions of e-c...

Background Several personality traits have been linked to addictive behaviours, including smoking and excessive drinking. We hypothesised that the combination of low conscientiousness, high extraversion and high neuroticism would be synergistically associated with smoking, excessive drinking and both behaviours combined. Methods Respondents aged 16...

Background Following the onset of the COVID-19 pandemic, in March 2020 health care delivery underwent considerable changes. It is unclear how this may have affected the delivery of Brief Interventions (BIs) for smoking and alcohol. We examined the impact of the COVID-19 pandemic on the receipt of BIs for smoking and alcohol in primary care in Engla...

Objectives: To examine trends in long-term (>6 months) vaping among adults in England. Design: Nationally-representative monthly cross-sectional survey. Setting: England. Participants: 179,725 adults (≥18y) surveyed between October 2013 and October 2023. Main outcome measures: We used logistic regression to estimate time trends in the prevalence of...

Nicotine vaping products (NVPs) and heated tobacco products (HTPs) are designed to replicate the sensory and behavioural aspects of smoking cigarettes while avoiding combustion. The success of these products as harm reduction tools will partially depend on their ability to satisfy smokers and alleviate nicotine-related withdrawal symptoms. This stu...

Background Studies conducted during the early stages of the pandemic documented mixed changes in smoking behaviour: more smokers quitting successfully but little change in prevalence. This study aimed to examine whether there have been sustained impacts of the COVID-19 pandemic on smoking patterns in England. Methods Data were from 101,960 adults...

This study assessed independent and interaction effects of the frequency of cannabis use, high-risk alcohol use, and depressive symptomology on motivation and attempts to quit cigarette smoking among adults who regularly smoked. Cross-sectional data are from the 2020 International Tobacco Control Four Country Smoking and Vaping Survey and included...

Objectives: To estimate time trends in cigarette consumption among smokers in England between 2008 and 2023, and explore differences by key potential moderators. Methods: We used data from 57,778 adult cigarette smokers participating in a nationally-representative monthly cross-sectional survey between January-2008 and September-2023. We estimated...

Background: The UK Government intends to implement a 'smokefree generation' policy prohibiting the sale of all tobacco products to people born after 2008. National surveys provide comprehensive data on cigarette smoking, but little is known about patterns of non-cigarette tobacco smoking across key population groups. Methods: Using data from a nati...

Objectives: The UK government is consulting on banning disposable e-cigarettes. This study aimed to describe trends in disposable e-cigarette use among adults in Great Britain since 2021 and establish who would currently be affected by a ban on disposables. Study design: Nationally-representative monthly cross-sectional survey. Methods: We analysed...

Introduction The COVID-19 pandemic and attendant lockdowns have had a substantial negative effect on alcohol consumption and physical activity globally. Pre-pandemic evidence in the adult population suggests that higher levels of physical activity were associated with higher levels of drinking, but it is unclear how the pandemic may have affected t...

Objective: To assess the role of self-reported desire over obligation in explaining continued smoking abstinence in recent ex-smokers. Method: A 12-month prospective study of 230 (45.2% female; mean age 45.4 years) adults in England who confirmed they had made a serious quit attempt and were not currently smoking at baseline. The predictor variable...

Background: Menthol cigarettes have been banned in Great Britain (GB) since May 2020. Still, menthol accessories and unlabelled cigarettes perceived as mentholated are available, and people can buy menthol cigarettes overseas or illicitly. This study assessed: trends in smoking menthol cigarettes among all adults and 18-to-24-year-olds in GB betwee...

Background It is not currently clear what impact alternative nicotine-delivery products (electronic cigarettes, heated tobacco products and snus) have on smoking rates and cigarette sales. Objective To assess whether access to these products promotes smoking in the population. Design and data sources We examined associations of alternative nicoti...

Background Alcohol and smoking brief interventions (BI) in general practice have been shown to be effective in lowering alcohol- and smoking-related harm. Aim Assess prevalence of self-reported BI receipt among increasing/higher risk drinkers and past-year smokers in Great Britain (GB) and associations between intervention receipt and socioeconomi...

Importance: In the last 3 years, people in England have lived through a pandemic and cost-of-living and health care crises, all of which may have contributed to worsening mental health in the population. Objective: To estimate trends in psychological distress among adults over this period and to examine differences by key potential moderators....

Introduction: In the last five years, there has been a dramatic shift in the types of nicotine products being purchased. This study aimed to estimate how much users spend on types of cigarettes and alternative nicotine products (e-cigarettes, nicotine replacement therapy (NRT), heated tobacco, nicotine pouches) and describe changes between 2018 an...

Background Smoking and excessive drinking place a strain on household budgets. We aimed to examine the impact of the cost-of-living crisis in Great Britain on the nature of smoking cessation and alcohol reduction attempts, and explore changes in health professionals offering support. Methods Data were from 14,567 past-year smokers and high-risk dr...

To help health economic modelers respond to demands for greater use of complex systems models in public health. To propose identifiable features of such models and support researchers to plan public health modeling projects using these models. A working group of experts in complex systems modeling and economic evaluation was brought together to dev...

Objective: To explore whether expenditure on national tobacco control mass media campaigns moderates the association between motivation to stop smoking and future quit attempts. Method: Data were from 2601 people who smoke participating in a population survey with 12-month follow-up between April 2015 and February 2021. We used logistic regressi...

Background: Several personality traits have been linked to addictive behaviours, including smoking and excessive drinking. We hypothesised that the combination of low conscientiousness, high extraversion and high neuroticism would be synergistically associated with smoking, excessive drinking and both behaviours combined. Methods: Respondents aged...

Background Adherence to health-protective behaviours (regularly washing hands, wearing masks indoors, maintaining physical distancing, carrying disinfectant) remains paramount for the successful control of COVID-19 at population level. It is therefore important to monitor adherence and to identify factors associated with it. This study assessed: 1)...

Background: This study aimed to examine whether there have been sustained impacts of the Covid-19 pandemic on smoking patterns in England. Methods: Data were from 101,960 adults (≥18y) participating in a monthly representative household survey between June-2017 and August-2022. Interview were conducted face-to-face until March 2020 and via telephon...

BACKGROUND: Tobacco smoking cessation is associated with improvements in mental health. This study assessed psychological distress, using the K6 non-specific screening tool ((items cover feelings of nervousness, hopelessness, restlessness, depression, ‘everything an effort’ and worthlessness), by smoking status, time since quit, and use of a non-co...

Aim To examine the level of support for tobacco availability policies across Great Britain (GB) and associations between support for policy and sociodemographic, smoking and quitting characteristics. Methods A cross-sectional representative survey (the Smoking Toolkit Study) of adults in GB (n=2197) during September 2021. Logistic regressions esti...

Background The COVID-19 pandemic has seen repeated government enforced restrictions on movement. This study aimed to evaluate longitudinal trends in physical activity (PA) in a self-selected UK-based sample and identify the key correlates of these trends. Methods From 23 April 2020 to 30 January 2021, measures of PA engagement were collected in a...

BACKGROUND: Due to the COVID-19 pandemic, from April 2020 data collection for the Smoking and Alcohol Toolkit Study (STS/ATS) shifted from a face-to-face to a telephone survey. In March 2022 a parallel face-to-face survey was conducted alongside the telephone survey to explore whether the change in data collection to telephone affected key sociodem...

Aim: To examine the association of self-reported COVID-19 disease status with cutting down, past-month and past-year quit attempts and motivation to stop smoking. Design and setting: Repeat cross-sectional survey, representative of the adult population in England. Participants: Past-year smokers, n = 3338 (aged ≥ 18 years) responding between M...

Background Novel nicotine delivery devices (NNDDs) are a safer alternative to combustible tobacco smoking. Understanding what factors can facilitate people who smoke to use NNDDs can inform intervention design and public health messaging. This study aims to explore the facilitators and barriers to NNDD use from the perspective of smokers without pr...

Background: We examined whether, in adults receiving behavioural support, offering e-cigarettes together with varenicline helps more people stop smoking cigarettes than varenicline alone. Methods: A two-group, parallel-arm, pragmatic randomised controlled trial was conducted in six English stop smoking services from 2019-2020. Adults enrolled on...

Background: There is a strong shared association between smoking tobacco and drinking alcohol. This study aimed to compare smoking prevalence and smoking characteristics in drinkers who were versus were not at risk of alcohol dependence in England. Methods: We used cross-sectional data from a monthly, nationally representative survey of adults i...

Objectives Understanding changes in moderate to vigorous aerobic physical activity (MVPA) and muscle-strengthening activity (MSA) at the start of the COVID-19 pandemic and their correlates (socio-demographics, health characteristics, living and exercise conditions and pre-pandemic MVPA/MSA) can inform interventions. Design A cross-sectional analys...

Smoking prevalence in several high-income countries is steadily declining but remains persistently high in ‘lower’ socioeconomic position (SEP) groups, contributing to inequities in morbidity and mortality. Smoking to relieve stress is a commonly endorsed motive for continued smoking; however, it remains unclear whether smoking to relieve stress ha...