Grey matter morphometry in young adult e-cigarette users, tobacco cigarette users & non-using controls

Area of Science:

• Neuroimaging
• Neurobiology
• Addiction Research

Background:

• Increasing prevalence of electronic cigarette (e-cigarette) use among young adults.
• Limited understanding of the neurobiological effects of daily e-cigarette use compared to traditional tobacco smoking.
• Need to investigate structural brain changes associated with substance use in young populations.

Purpose of the Study:

• To examine the impact of regular, exclusive e-cigarette use on grey matter morphometry in young adults (18-25 years).
• To compare brain structure differences between exclusive e-cigarette users, tobacco cigarette smokers, and non-using controls.

Main Methods:

• Structural MRI data acquired from 78 participants across three groups: daily e-cigarette users, daily tobacco cigarette smokers, and controls.
• Voxel-based morphometry (VBM) employed to assess differences in grey matter volume (GMV).
• Partial correlation analyses conducted to explore associations between GMV, smoking history, and nicotine dependence.

Main Results:

• Tobacco cigarette smokers showed significant GMV reductions in the left fusiform gyrus (FG), left/right inferior temporal gyrus (IFG), right middle temporal gyrus (MTG), and right middle cingulate gyrus (MCG) compared to controls.
• Anterior cingulate cortex (ACC) GMV was reduced in tobacco smokers compared to both e-cigarette users and controls, independent of nicotine history.
• In tobacco smokers, GMV in FG, IFG, MTG, and MCG negatively correlated with exposure history, not nicotine dependence; ACC GMV showed no such association.

Conclusions:

• Daily tobacco cigarette smoking is associated with significant grey matter volume reductions in specific brain regions in young adults.
• E-cigarette use did not show similar GMV reductions, suggesting a potentially distinct neurobiological impact compared to tobacco smoking.
• Findings imply that non-nicotine components of tobacco smoke or pre-existing vulnerabilities may contribute to observed brain structural differences.