Posted 11.14.2016 | by AMRA
Life expectancy of tobacco smokers is cut by 10 years, and smoking is responsible for nearly a half-million deaths in the United States each year. The vast majority of smokers want to quit, but unassisted attempts usually fail, and those that succeed often end in relapse. Studies show that acute stress increases both the likelihood of smoking and the risk of relapse. That is the reason why stress reduction techniques are often offered as a key component in smoking cessation programs.
Kober et al. [Neuroimage] investigated differences in the brain’s response to stress in cigarette smokers participating in one of two smoking cessation interventions: mindfulness training for smoking (MT) or the American Lung Association’s Freedom from Smoking (FFS) program.
The study reported on 23 adult smokers (average age = 48, 70% male, 58% Caucasian) who volunteered for a smoking cessation intervention. The participants were randomly assigned to either MT or FFS, and the relative success of these interventions was reported on in a separate publication (both interventions were effective, with MT participants demonstrating a greater improvement in smoking reduction). Both group interventions met twice a week over a four-week period. The MT program emphasized present-moment awareness and acceptance as strategies for coping with negative emotions and cravings and utilized mindfulness and loving-kindness meditations. The FFS program emphasized self-monitoring, identifying triggers, developing individualized quitting plans, maintaining a healthy lifestyle, and cognitive-behavioral coping strategies.
The participants underwent functional magnetic resonance brain imaging (fMRI) immediately after smoking cessation treatment. The participants listened to recordings of individualized stressful and neutral scenarios during their brain scans. The individualized scenarios were developed based on actual stressful life events the participants had reported during prior interviews in order to assure that the scenarios would actually trigger a stress-response. The researchers then compared participant brain activity while listening to the stressful versus neutral scenarios. They also monitored the number of cigarettes smoked per day during the intervention and three-month follow-up periods.
Listening to the stressful scenarios significantly increased participant’s reported level of stress (Cohen’s d=.60) and cigarette cravings (d=.36), whereas the neutral scenarios did neither. For the entire sample, brain stress response in a wide variety of limbic, insular, and midbrain structures was inversely correlated with post-treatment and three-month follow-up reductions in smoking (d >1.0). That is, the smokers who had the greatest success in decreasing their smoking also showed the smallest brain stress responses, whereas the least successful showed the highest brain stress reactivity.
Comparing treatment groups, FFS participants showed significantly larger brain stress responses than MT participants in 10 different brain regions. On the other hand, no brain region showed a significantly larger stress response for the MT participants. There were several stress-responsive brain regions (the amygdala, the insula, and the parahippocampal gyrus) that were specifically associated with successful smoking reduction and showed comparatively lower levels of stress-reactivity for MT participants (d >1.0).
Results support the hypothesis that mindfulness training for smoking successfully alters brain stress reactivity, and that this reduction in stress reactivity facilitates smoking reduction. The study also raises the possibility that mindfulness and acceptance strategies may be more successful at reducing smoker’s stress reactivity than cognitive behavioral strategies, at least as they are taught in FFS. The study is limited by its small sample size.
Kober, H., Brewer, J. A., Height, K. L., & Sinha, R. (2016). Neural stress reactivity relates to smoking outcomes and differentiates between mindfulness and cognitive-behavioral treatments. NeuroImage.