Cost-Utility Analysis of Internet-Delivered Cognitive Control Training Plus Treatment as Usual Versus Treatment as Usual Alone for Relapse Prevention in Major Depressive Disorder

BackgroundDepression is a highly recurrent condition, and many individuals remain vulnerable to relapse during the remission phase. Cognitive Control Training (CCT), particularly the internet-delivered adaptive Paced Auditory Serial Addition Task (aPASAT), has shown promise in preventing relapse, yet its health economic value has not been evaluated. This study assessed the cost-utility of adding aPASAT to treatment as usual (TAU) for adults in remission from major depressive disorder (MDD).MethodsA Markov state-transition model simulated a hypothetical cohort of Belgian adults aged 18-65 years in remission from MDD over a five-year time horizon from a healthcare payer perspective. Model parameters were mainly derived from published literature. Outcomes included incremental costs, incremental quality-adjusted life years (QALYs), incremental cost-effectiveness ratios (ICERs), and incremental monetary benefit (INMB). Uncertainty was evaluated using one-way sensitivity, two-way sensitivity and probabilistic sensitivity analysis (5,000 simulations), and multiple deterministic scenario analyses.ResultsIn the base case, aPASAT + TAU dominated TAU alone, yielding additional QALYs (Δ = 2192) and lower healthcare costs (Δ = –€77.38M), resulting in an INMB of €182.6M at a €48,000 per QALY threshold. Probabilistic sensitivity analysis indicated a 99.9% probability of cost-effectiveness. Scenario analyses varying adherence, coverage, remission prevalence, and time horizon consistently confirmed cost savings and improved health outcomes.ConclusionInternet-delivered CCT using the aPASAT appears to be a cost-effective strategy for preventing MDD relapse. Its low-cost and fully unguided format supports scalable integration into stepped, prevention-oriented mental healthcare systems.