Early program participation and treatment retention in outpatients with gambling disorder: a real-world retrospective...

Real-world evidence on outpatient program participation and time to treatment discontinuation (treatment retention) in patients with gambling disorder in Japan remains limited. In this study, we characterized baseline clinical and sociodemographic profiles of outpatients receiving care for gambling disorder and described patterns of engagement, including treatment retention, in a group program.

We retrospectively enrolled outpatients with gambling disorder who first visited Tarumi Hospital between April 2019 and December 2023 and followed them up until December 2024. Program participation referred to attendance at a structured cognitive behavioral therapy (CBT)-based group program designed as 24 sessions over 1 year, provided in addition to usual outpatient care. The primary analysis used a Cox proportional hazard analysis, with program participation as a time-dependent covariate; a 30-day landmark analysis was used to evaluate retention after day 30 among patients retained in the program for at least 30 days. Abstinence at the final observation was defined as a self report of no gambling in the preceding 2 weeks and was compared between the program participation and non-participation groups among patients who gambled at baseline.

The program was initiated for 82 patients within 30 days of their first hospital visit, and 55 patients did not participate in the program. By day 30, retention was higher in the participation group than in the non-participation group (89.0% vs. 45.5%). Program participation was associated with a lower estimated hazard of discontinuation (hazard ratio = 0.64, 95% confidence interval 0.40-1.03; p = 0.067), but the estimate was imprecise and compatible with no difference. Among patients retained beyond day 30, retention after day 30 did not differ between groups (log-rank p = 0.886). Abstinence was higher in the participation group than in the non-participation group among patients who discontinued treatment within 3 months but not among those who continued treatment for ≥ 3 or ≥ 6 months.

Early participation in a structured CBT-based program may be associated with a longer observed retention duration, with divergence occurring within 30 days. Strengthening clinical contact soon after the first visit may be a practical priority; prospective studies with standardized severity and motivational measures are warranted.