Two-hour nicotine withdrawal does not alter interoceptive dysfunction in male smokers with nicotine dependence: evidence from heartbeat-evoked potentials

Nicotine dependence (ND) is an addictive disorder involving physical and psychological dependence on nicotine. Nicotine withdrawal encompasses a spectrum of physiological and psychological changes, often manifesting as significant emotional dysregulation. Understanding whether smokers have interoceptive dysfunction and the effects of 2-hour nicotine withdrawal on this function may provide valuable insights to enhance smoking cessation programs. In this study, we used heartbeat-evoked potentials (HEPs) to investigate male smokers’ interoceptive function and the changes in this function after 2-hour nicotine withdrawal. Participants included 32 ND patients and 32 healthy controls (HCs), and HEP measurements were performed during the heartbeat attention task. The HEP amplitudes were compared by using a mixed model Repeated Measure Analysis of Variance. HEP amplitudes in the ND group were lower than those in the HC group, especially evident in the central lobe and parietal lobe regions. However, there were no differences in electrocardiogram (ECG) amplitudes between the two groups. There were no differences in the HEP amplitudes between baseline (Time 1) and withdrawal state (Time 2) in all brain regions for the ND group, and 2-hour nicotine withdrawal did not alter the HEP amplitudes. HEP amplitudes in central lobe and parietal lobe regions were lower than those in frontal lobe region in the ND group, and parietal lobe region had the lowest HEP amplitudes. The somatic awareness scores and autonomic nervous system scores of Body Perception Questionnaire in the ND group were lower than those in the HC group. Evidence from the abnormal HEP characteristic suggests that ND patients have interoceptive dysfunction. However, we found no evidence that 2-hour nicotine withdrawal improved interoceptive dysfunction in ND patients. Targeting interoceptive function in smoking cessation programs offers a novel approach to addressing the physiological and psychological aspects of nicotine dependence, providing a comprehensive strategy for improving outcomes in individuals striving to quit smoking.