Self-Guided Internet-Based Mindfulness-Informed Stress Management for Generalized Anxiety Disorder: Randomized Controlled Trial With Longitudinal Network Analysis.

BACKGROUND: Generalized anxiety disorder (GAD) is characterized by stress-anxiety reinforcement cycles. Evidence for brief, self-guided, internet-based stress management as an adjunct to pharmacotherapy remains limited.

OBJECTIVE: This study aimed to evaluate the efficacy of an 8-week self-guided, internet-based stress management program (iSM) incorporating mindfulness techniques as an adjunct to treatment as usual (TAU) in adults with GAD and to examine individual predictors of response and symptom dynamics.

METHODS: A single-blind, parallel-group, superiority randomized controlled trial was conducted at Tongji Hospital, Wuhan, China. A total of 140 adults with GAD were randomly assigned to iSM+TAU (n=73) or TAU (n=67). Outcome assessors were blinded to group allocation. The iSM intervention consisted of 8 weekly self-guided online modules integrating mindfulness-based training and Baduanjin-based stretching exercises. TAU comprised routine pharmacotherapy. Primary outcomes were posttreatment changes in anxiety and depressive symptoms. Secondary outcomes included sleep quality, somatic symptoms, social functioning, mindfulness, rumination, and perceived stress. Exploratory cross-lagged panel network (CLPN) and random-intercept cross-lagged panel modeling (RI-CLPM) analyses were used to examine temporal symptom dynamics.

RESULTS: All 140 randomized participants were included in the intention-to-treat analysis. Compared with TAU, iSM+TAU showed greater reductions at posttreatment in anxiety (Cohen d=-0.277, 95% CI -0.521 to -0.033) and depressive symptoms (Cohen d=-0.309, 95% CI -0.592 to -0.026). Significant between-group differences were also observed in somatic symptoms (Cohen d=-0.340, 95% CI -0.604 to -0.077), state anxiety (Cohen d=-0.537, 95% CI -0.849 to -0.224), mindfulness (Cohen d=0.666, 95% CI 0.327-1.006), rumination (Cohen d=-0.344, 95% CI -0.626 to -0.062), and perceived stress (Cohen d=-0.429, 95% CI -0.725 to -0.133), but not in sleep quality or social functioning. No serious adverse events were reported. Median session completion was 7 of 8. In exploratory analyses, higher baseline acting with awareness predicted greater treatment response (standardized β=0.167; 95% CI 0.031-0.335), whereas higher trait anxiety predicted poorer outcomes (standardized β=-0.150; 95% CI -0.234 to -0.002). CLPN and RI-CLPM identified 2 key within-person pathways, a bidirectional association between perceived stress (mean β=0.219; P<.001) and state anxiety (mean β=0.165; P=.02), and a unidirectional effect of mindfulness on subsequent anxiety reduction (mean β=-0.285; P<.001).

CONCLUSIONS: To our knowledge, this is the first trial to evaluate a brief, self-guided, culturally adapted digital mindfulness intervention as an adjunct to pharmacotherapy in Chinese adults with GAD. The intervention showed clinically meaningful benefits and practical potential as a scalable, resource-efficient approach. Unlike prior studies focused mainly on symptom outcomes alone, this trial combined a randomized design with CLPN and RI-CLPM analyses to provide preliminary insight into symptom change processes over time, adding a more process-oriented analytic perspective that may inform future intervention refinement.