Salient Cue Reactivity and Eating Behaviors in Ex-Smokers, Abstinent Alcohol Use Disorder, and Obesity

Introduction Neural cue reactivity is increasingly being investigated as a biomarker of treatment response and relapse prediction in addiction disorders. While aberrant brain responses to salient cues (e.g., drugs) have been widely reported in addiction, it is unclear whether these brain responses persist during longer-term abstinence and how they compare between substance use disorder and obesity and relate to potential differences in eating behaviors. As part of the Gut Hormones in ADDiction (GHADD) neuroimaging study, we investigated how salient cue reactivity to drugs or food, craving and eating behaviors compare in three clinical populations where alterations have been previously observed: abstinent nicotine use disorder (NUD), alcohol use disorder (AUD), and obesity. Methods This study compared group differences in salient cue reactivity and eating behaviors among ex-smokers ( n = 25, ExS), adults with alcohol dependence but who are abstinent ( n = 26, AAD), and adults with obesity who were actively dieting ( n = 26, OB). Participants completed a high-energy food, preferred alcohol, and cigarette functional magnetic resonance imaging (fMRI) cue reactivity task, along with eating behavior questionnaires, appetite visual analogues scales, and an ad libitum test meal. Results ExS exhibited greater blood oxygen level dependent (BOLD) signal to high-energy food pictures in several reward processing regions in both whole brain and region of interest (ROI) analyses, compared with the OB and AAD groups, with no difference in their appeal rating. Compared with the OB group, ExS exhibited greater BOLD signal to cigarette pictures in the frontal gyrus, orbitofrontal cortex, frontal pole, and insula, with no difference in their appeal rating. There were no group differences in preferred alcohol cue reactivity. The AAD group rated sweet taste as more pleasant and consumed more calories from sweet dishes in the ad libitum meal than the OB and ExS groups. Conclusions The presence of heightened cue reactivity to high-energy foods in ex-smokers could contribute to post-quitting weight gain after smoking cessation. Neuroimaging findings were consistent with the persistence of some salient drug cue reactivity, despite absence of craving, after medium term abstinence in ExS, but not in AAD. This study also adds to the body of evidence supporting a sweet taste preference endophenotype predisposing individuals to AUD. These changes in eating behavior in NUD and AUD may provide targets for treatments to reduce substance misuse and facilitate abstinence.