Table 1. Key mechanisms underlying tobacco dependence in individuals with schizophrenia.

nAChRs: nicotinic acetylcholine receptors

Mechanism	Description	Impact on Tobacco Use
Nicotine's effect on dopamine release [14]	Nicotine increases dopamine levels in the brain, providing a sense of pleasure and reward	Individuals with schizophrenia may use nicotine to self-medicate, increasing dependence
Cognitive dysfunction [11]	Schizophrenia is associated with cognitive impairments such as memory, attention, and executive functioning	Tobacco use may improve attention and working memory, reinforcing the habit
Negative symptoms [2]	Schizophrenia often involves negative symptoms such as lack of motivation and social withdrawal	Nicotine may temporarily alleviate these symptoms, encouraging repeated use
Altered nicotine receptor sensitivity [15]	Schizophrenia may involve alterations in the brain’s nAChRs	This altered sensitivity could enhance nicotine’s reinforcing effects, increasing dependence
High stress and anxiety levels [16]	High levels of stress and anxiety often accompany schizophrenia	Nicotine is used as a coping mechanism to relieve stress, fostering addiction
Impaired impulse control [17]	Individuals with schizophrenia often exhibit poor impulse control and higher susceptibility to addiction	Difficulty in resisting cravings or controlling tobacco use, leads to higher dependence
Comorbid substance abuse [18]	Schizophrenia frequently co-occurs with substance use disorders, including alcohol and drugs	The presence of other addictions may heighten nicotine dependence
Social isolation and marginalization [19]	Many individuals with schizophrenia face social isolation and stigma	Smoking may become a social or coping activity, reinforcing habitual use