Potential for non-combustible nicotine products to reduce socioeconomic inequalities in smoking: a systematic review and synthesis of best available evidence

Abstract

Background While some experts have emphasised the potential for e-cigarettes to facilitate cessation among smokers with low socioeconomic status (SES), there is limited evidence of their likely equity impact. We assessed the potential for electronic cigarettes and other non-combustible nicotine-containing products (NCNPs) to reduce inequalities in smoking by systematically reviewing evidence on their use by SES in countries at stage IV of the cigarette epidemic. Methods Ten electronic databases were searched in February 2017 using terms relating to e-cigarettes, smokeless tobacco and nicotine replacement therapy (NRT); and socioeconomic status. We included studies published since 1980 that were available in English and examined product use by SES indicators such as income and education. Data synthesis was based on those studies judged to be of medium- to high-quality using guidelines adapted from the Critical Appraisal Skills Programme. Results We identified 54 studies describing NCNP use by SES across 12 countries, of which 27 were judged of sufficient quality to include in data synthesis. We found mixed patterns of e-cigarette current use by SES, with evidence of higher use among low-income adults but unclear or mixed findings by education and occupation. In contrast, smokeless tobacco current use was consistently higher use among low SES adults. There was very limited evidence on the SES distribution of NRT in adults and of all NCNPs in young people. Conclusions The only NCNP for which there are clear patterns of use by SES is smokeless tobacco, where prevalence is higher among low SES groups. While this suggests a potentially positive impact on inequalities in smoking (if NCNP use displaces smoked tobacco use), this has not been seen in practice. These findings do not support the suggestion that e-cigarettes have the potential to reduce social inequalities in smoking, since i) current evidence does not show a clear trend of higher e-cigarette use in population groups with higher tobacco consumption, and ii) the experience of smokeless tobacco suggests that – even where NCNP use is higher among low SES groups – this does not necessarily replace smoked tobacco use in these groups.

Inequalities, harm reduction and non-combustible nicotine products: a meta-ethnography of qualitative evidence

“…This review is part of a larger project and the results of a literature review on quantitative data are reported in a separate paper [7]. A full protocol of this project, including the quantitative and qualitative reviews, has been registered with PROSPERO (ID: CRD42017080672) [37].…”

“…Meanwhile, quantitative data continues to demonstrate a concentration of smoking within socioeconomically disadvantaged communities across Europe [6]. A recent systematic review of quantitative evidence, conducted by the authors of this review, found limited evidence that non-combustible nicotine products (NCNP) had reduced or are likely to reduce socioeconomic inequalities in smoking [7]. The quantitative review included all types of NCNP, including e-cigarettes, in order to explore differential potential for reducing inequalities of the wide range of products that now exists.…”

Inequalities, harm reduction and non-combustible nicotine products: a meta-ethnography of qualitative evidence

“…This review is part of a larger project and the results of a literature review on quantitative data are reported in a separate paper [7]. A full protocol of this project, including the quantitative and qualitative reviews, has been registered with PROSPERO (ID: CRD42017080672) [38].…”

“…A recent systematic review of quantitative evidence, conducted by the authors of this review, found limited evidence that non-combustible nicotine products (NCNP) had reduced or are likely to reduce socioeconomic inequalities in smoking [7]. The quantitative review included all types of NCNP, including ecigarettes, in order to explore differential potential for reducing inequalities of the wide range of products that now exists.…”

Inequalities, harm reduction and non-combustible nicotine products: a meta-ethnography of qualitative evidence

“…Meanwhile, quantitative data continues to demonstrate a concentration of smoking within socioeconomically disadvantaged communities across Europe [6]. A recent systematic review of quantitative evidence, conducted by the authors of this review, found limited evidence that non-combustible nicotine products (NCNP) had reduced or are likely to reduce socioeconomic inequalities in smoking [7]. The quantitative review included all types of NCNP, including ecigarettes, in order to explore differential potential for reducing inequalities of the wide range of products that now exists.…”