Effects of smoking cessation treatment attendance on abstinence: The moderating role of psychologically based behavioral health conditions.

Available smoking cessation treatments have shown only modest quit success. Presence of a psychologically based behavioral health condition (PBHC), such as depression, anxiety, or addiction, can impact smoking cessation treatment engagement and quit success; however, the differential effect of treatment engagement on smoking cessation outcomes across smokers with and without a PBHC is unknown. The current study examined the moderating effect presence (versus absence) of a PBHC on the relation between treatment attendance and early smoking abstinence following a 4-session smoking cessation treatment. Participants included 529 (45.9% male; Mage = 38.23 years, SD = 13.56; 75.4% White) smokers enrolled in a large randomized controlled trial evaluating the efficacy of a transdiagnostic smoking cessation treatment. A repeated-measures latent class analysis (RMLCA) was conducted to examine treatment attendance. The effects of treatment attendance, PBHC (present/absent), and their interaction were modeled on biochemically-verified point prevalence abstinence using a latent growth curve from 1-week to 1-month post-quit. The RMLCA provided evidence for three classes: Drop-outs (n = 197), Titrators (n = 89), and Completers (n = 243). A significant interaction emerged such that Completers without a PBHC were significantly more likely to be abstinent relative to Completers with a PBHC (b = 2.69, SE = 0.67, p < .001) and Titrators without a PBHC (b = 3.36, SE = 0.80, p < .001). These results provide novel data that implicate the clinical importance of treatment attendance and PBHC status on smoking abstinence.