(PS5-A1) Impact of Home Practice on Treatment Responder Status Within a Randomized Trial of Group Yoga, CBT, and Stress Education for Generalized Anxiety Disorder

Background: Home practice is an important component of cognitive behavioral therapy (CBT) and is theorized to be a mechanism of treatment change. However, less is known about the role of yoga home practice in anxiety treatment outcomes. This study examines the association between home practice engagement and anxiety outcome within a two-site randomized control trial comparing Kundalini yoga, CBT, and stress education (SE) group treatments for generalized anxiety disorder (GAD; Simon et al, 2021). We hypothesized that better engagement with home practice would be associated with treatment responder status across treatment arms.

Methods: 153 adults with a primary diagnosis of GAD (71% women, M age=34±14) were randomized to 12 sessions of group yoga (N=60), CBT (N=67), or SE (N=26), attended two or more sessions, and completed post-treatment assessment. Participants were instructed to complete 20 minutes of daily home practice for all treatments. Home practice was measured as: 1) self-reported average days per week of homework; and 2) compliance rated by staff on a 0 (none completed)-6 (all completed) Likert scale.  Treatment responders had a score of 1 (very much improved) or 2 (much improved) on the Clinical Global Impression-Improvement (CGI-I) assessed at Week 12 (post-treatment) and 38 (follow-up). 

Results: All of the aforementioned subjects submitted one or more homework logs and were included in analyses. On average, subjects engaged in approximately half of the prescribed days of practice (2.9±1.4 days/week) and were moderately compliant (3.6±1.3). Treatment responders (N=90, 59%) practiced for more days per week (3.1±1.2 vs. 2.6±1.5, t(151) = -2.2, p=.03) and were more compliant (3.9±1.1 vs. 3.3±1.4, t(109) = -2.8, p=.006) than non-responders (N=63, 41%). In logistic regressions that accounted for treatment arm and number of sessions attended, home practice compliance predicted outcome at post-treatment (OR=1.37, 95% CI [1.02, 1.84], p=.037) and at follow up (OR=1.39, 95% CI [0.99, 1.96], p=.059), but weekly days of practice did not (OR=1.18, 95% CI [0.89,1.58], p=.259). Days practiced were similar between the yoga and CBT groups (3.0±1.4 vs. 3.2±1.2, t(125)= -1.1, p= 0.30), whereas compliance scores were marginally higher for subjects in CBT compared to those in yoga (3.9±1.0 vs. 3.5±1.3, t(106.1)= -1.9, p=0.057).



Conclusions:  Average days per week of home practice and staff-rated homework compliance were related to treatment response for individuals with GAD, but only compliance predicted response when accounting for treatment arm and session attendance. Results were limited by missing data due to study drop out. Further analyses will incorporate week-by-week trajectories of home practice to examine the optimal quantity and pattern of home practice needed for anxiety response. Analyses by treatment arm will tailor home practice recommendations to each treatment modality.