採用腦影像探討長期K他命使用者認知功能損害與性別差異-第2年計畫

Background: Chronic ketamine use leads to ulcerative cystitis, neurocognitive impairments, including deficits in working memory and executive functions and other social problems. To our knowledge, despite increased physical, psychological and social concerns about ketamine use, no study has systematically documented the effects of ketamine use on prefrontal cortex, cerebral structures and functions. It is imperative to accumulate more understanding of impacts on brain damage of chronic ketamine use because ketamine influences brain in the ways different from heroin, cocaine and amphetamine. This study aims to examine the chronic ketamine exposure effects to higher cognitive function, brain structural and functional change on imaging studies. Brain network and connectivity change under chronic ketamine exposure will also be explored. Methods: Participants received structural and resting functional imaging scan. They also took the N-back task during brain scan. SST task was performed outside machine. Barratt Impulsiveness Scale (BIS), Buss-Perry Aggression Questionnaire, Sensitivity to Punishment and Sensitivity to Reward Questionnaire (SPSRQ ) and Symptom Check List-90 (SCL-90) were also done by all the participants. Results: We recruited 50 ketamine users without using other psychoactive substances and 48 healthy controls. In Ketamine users group, there are 39 men and 11 women, with mean ages of 21.35 (SD=4.80) and mean education of 9.6 (SD=2.32) years; in healthy smokers group, there are 29 men and 19 women, with mean ages of 27.12 (SD=5.38) and mean education of 14.63 (SD=2.18) years. The VBM analysis showed ketamine users have larger right inferior frontal gyrus and smaller left precuneus. The volume of left precuneus was negative correlated with BIS and SCL-90 scores. Besides, the brain network analysis showed chronic ketamine users had less active executive network (ECN) compared to health smoker controls. The correlation between ECN and N-back task performance was observed in HC but not in KU group. Conclusion: For ketamine misuse is a major issue in Asia, it’s quite important to gain more scientific information about the brain effects under chronic ketamine use. Ketamine emerges to be the new antidepressant for refractory depressive patients. Thus understanding the long-term consequences of ketamine use is imperative. The results can be used to develop and design treatment programs, including counseling and psycho-education.