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88 active trials for Smoking

Electronic Hookah and Endothelial Cell Function

Electronic nicotine delivery systems (ENDS) are a new rapidly growing global epidemic. More recently, electronic (e-) hookahs, have increased in popularity in the United States, with the greatest uptake by young female adults, who endorse marketing claims that these products are safer alternatives to traditional flavored hookah tobacco smoking. Unlike other ENDS such as e-cigarettes, e-hookah bowls are used through traditional water-pipes, allowing the vapor-containing nicotine, propylene glycol, glycerin, and flavorings-to pass through a water-filled basin, potentially altering the vapor, before it is inhaled through the user's mouth. Contributing to e-hookah bowls' popularity is the belief that the flavored smoke is detoxified as it passes through the water-filled basin, rendering e-hookah a safer tobacco alternative. However, an e-hookah bowl delivers flavored nicotine by creating a vapor of fine particles and volatile organic compounds that could induce vascular toxicity. The objective of this project is to investigate the effects of e-hookah bowl inhalation on endothelial function, vascular biomarkers and volatile compounds; and molecular mechanisms underlying e-hookah induced endothelial injury using freshly harvested human endothelial cells with a specific role of nicotine. In a cross-over study design, the investigators will first assess endothelial function measured by brachial artery flow-mediated dilation and markers of oxidative stress and inflammation in 18 young healthy hookah smokers 21-39 years old, before and after two separate 30-minute e-hookah bowl inhalation sessions using one brand of nicotine-containing and nicotine-free e-hookah liquid and, for control comparison, before and after sham hookah smoking. Then, in freshly harvested venous endothelial cells the investigators will assess nitric oxide bioavailability, and expression of markers of inflammation and oxidative stress before and after the sessions. To compare specific exposures across conditions, the research team will measure changes in plasma nicotine, and highly specific urinary mercapturic acid metabolites of acrolein and benzene. This proposed study will provide critical scientific data on the impact of e-hookah inhalation on vascular health and mechanisms of exposure on known cardiac risk factors. Results will provide critical data to the FDA to inform the development of regulations specific to hookah.

Start: November 2019
Opioids and Smoking Cessation

The selection hypothesis of smoking prevalence posits that smokers who are not able to quit successfully are "burdened" by specific characteristics that make it more challenging to quit1. For example, those less successful in quitting smoking may be more nicotine dependent or more likely to suffer from substance use, psychiatric, or medical conditions. In line with this perspective, smoking prevalence has stabilized in the US, presumably because the remaining population has become increasingly representative of those "at-risk smokers" who are unable to quit2. Emerging evidence suggests that persons who suffer from opioid misuse, defined as opioid use without a prescription, at a dose or frequency higher than prescribed, or for a non-medical purpose (e.g., getting high),3 may constitute such a high-risk group. Opioid misuse affects greater than 16% adults who use opioids4 and up to 29% of those with chronic pain.5 The prevalence of tobacco smoking in this group may exceed twice that observed in the general population, and smokers misusing opioids are almost twice as likely to be dependent on nicotine6,7. Yet, the role of opioid misuse in periods of early abstinence and smoking cessation has yet to be explored. The main objective of the present proposal is to fill existing gaps in knowledge by examining the extent to which opioid misuse is associated with decreased success during early smoking abstinence and over the course of an attempt to quit smoking, and to identify mediators and moderators of opioid-smoking relations in this context. This contribution is clinically-significant from a public health standpoint because it will directly guide the development of novel psychosocial/behavioral smoking cessation interventions to help this high-risk population of smokers quit by targeting unique vulnerability processes that result in poor cessation outcomes.

Start: January 2020