| This study was conducted to determine if depression vulnerability is a moderator of smoking cessation treatment within a previously designed clinical trial analyzing the efficacy of group cognitive behavioral therapy relative to a time-equated psychoeducational comparison group. By analyzing a modest sample size (N = 100) comprised of both depression-vulnerable smokers and smokers not prone to depression, a moderator effect of depression proneness on efficacy of cognitive behavior therapy (CBT) was found. More specifically, the baseline self-reported depression vulnerability (sample median split on the pre-treatment Depression Proneness Inventory) moderated treatment response, such that depression-prone smokers had better post-treatment abstinence rates in CBT whereas less depression-prone smokers had better post-treatment abstinence rates in the comparison condition. Additional analyses were completed to see if there were any outcome differences in (a) cognitive coping skills, (b) acceptance, (c) dichotomous thinking, and (d) outcome expectancies for smoking between the treatment conditions among the entire randomized sample, the highly depression prone sample, and the low depression prone sample. Although this study found a moderator effect of depression vulnerability, the outcome differences across coping skills, acceptance, dichotomous thinking, and outcome expectancies suggest the need for further research. Improvement in compensatory coping skills adversely impacted smoking cessation outcomes for low depression prone participants and did not impact smoking outcomes for the highly depression-vulnerable. The decrease of dichotomous thinking in the highly depression prone also adversely impacted smoking cessation outcomes. Measures of acceptance did not appear to play a significant role in overall smoking cessation treatment outcome despite the level of depression vulnerability. Finally, both positive and negative expectations related to smoking decreased across the entire sample in both treatment conditions while those who were highly depression prone potentially benefited from internalizing negative consequences of smoking, which occurred more often in CBT relative to the Comparison condition. Although future research is needed to clarify these findings, practitioners may be able to enhance smoking cessation outcomes by measuring depression proneness at baseline and incorporating CBT mood-management interventions only for the highly depression-vulnerable. |
