A Comparison of Electronic Cigarettes and Combination Nicotine Replacement Therapy among Individuals with Obesity who Smoke

Brown University, Providence RI

Investigators

Linked publications, trials & patents

Abstract

PROJECT SUMMARY Tobacco use, poor diet and physical inactivity are the leading causes of preventable death in the US.1, 2 The life expectancy of individuals who smoke cigarettes and have obesity is seven years shorter than that of normal-weight individuals who smoke and 13 years shorter than that of normal-weight individuals who do not smoke.3 Risk of all-cause mortality is 3.5 - 5 times higher among individuals with obesity who smoke cigarettes compared to normal-weight individuals who have never smoked.4 Smoking increases insulin resistance and central adiposity (i.e., the accumulation of fat tissue around the abdominal area), increasing the risk of metabolic syndrome, diabetes, and CVD. 5-7 Because smoking and obesity have synergistic health risks, finding effective ways of reducing smoking among individuals who smoke cigarettes with obesity (SWO) is a public health priority. Although SWO are at disproportionately higher risk for disease, disability, and premature death, they may be reluctant to give up smoking due to the fear of difficulty managing their weight without cigarettes. Individuals who quit smoking typically gain weight,12 and pre-cessation obesity is a significant predictor of weight gain after quitting.13 Compared to normal-weight individuals who smoke, SWO report greater likelihood of smoking to control their appetite and weight, greater concern about post-cessation weight gain, less confidence in their ability to maintain their weight without smoking, and greater likelihood of resuming smoking if they gain too much weight.14-16 Because nicotine has been shown to reduce appetite and caloric intake,17 understanding whether other reduced-risk, nicotine-containing products may be viable alternatives to cigarettes is of particular importance to this population. Nicotine and tobacco products lie on a continuum of risk, with combustible cigarettes as the most harmful to health, electronic cigarettes (EC), i.e., battery-powered devices that heat nicotine, considerably less harmful, and medicinal nicotine (e.g., nicotine replacement therapy; NRT) as the least harmful.18-20 Combination NRT, consisting of a long-acting nicotine product (nicotine patch), plus a short-acting nicotine product (lozenge, gum), is typically recommended as an efficacious cessation treatment. However, EC may be more effective than NRT for reducing smoking in SWO. While adherence to NRT is typically poor,21 EC are highly appealing to individuals who smoke,22 which improves compliance23, 24 and EC may be more effective for preventing weight gain than NRT for both behavioral and pharmacological reasons. While both approaches may reduce cigarette use in SWO, their efficacy, acceptability, and potential to limit weight gain and improve health have not been compared among SWO. We aim to randomize 60 SWO to receive (1) EC, (2) NRT (nicotine patch plus lozenge or gum), or (3) to a no-product control (CON) condition for 8 weeks. All study procedures will be conducted remotely. At baseline and 1, 2, and 3-months follow-up we will measure cigarette, EC, and NRT use, smoking cessation attempts, product acceptability and adherence, tobacco exposure (i.e., exhaled carbon monoxide; CO), indicators of obesity (i.e., weight, central adiposity), and clinical indicators (i.e., glucose regulation, lipid metabolism, inflammation, blood pressure) to inform a future fully-powered clinical trial. Aim 1: Assess study feasibility, preliminary efficacy, and obtain preliminary effect size data to inform a fully-powered future trial. (H1a) Those assigned to EC or NRT will have a greater reduction in cigarettes per day (CPD) and CO, and more quit attempts than those in CON at 1, 2, and 3-months follow-up. (H1b) The size of the effect of EC on CPD and CO reductions will be larger than that of NRT. Aim 2a: Assess assigned product acceptability and usage. (H2a) Those assigned to EC will report greater product acceptability (e.g., helpfulness, satisfaction) and will have greater product adherence (% days product use) at 1 and 2 months than those assigned to NRT. Effect sizes for acceptability and adherence outcomes will be calculated inform future mechanistic analyses (i.e., mediation of CPD and CO outcomes). Aim 2b: Determine the effects of product provision on indicators of obesity and relevant clinical outcomes at follow-up. (H2b) We hypothesize that those in EC and NRT will have greater improvements in glucose regulation, lipid metabolism, inflammation, and blood pressure (from reduced tobacco exposure) than those in CON at 2 months (end of treatment) and (H2c) that, among those with significant reductions in their smoking, relative to NRT, EC will result in less gain in weight and central adiposity at 1, 2, and 3 months. This study will provide key information on the potential impacts of reduced risk nicotine products in a population that is highly vulnerable to smoking-related morbidity and mortality. Findings could inform clinical practice recommendations when treating individuals with obesity who smoke cigarettes.