[Japan-multimodal intervention trial for prevention of dementia (J-MINT) and its societal implementation: Concepts,...

The prevalence of dementia and mild cognitive impairment (MCI) is projected to increase further in Japan, underscoring the urgent need for effective non-pharmacological prevention strategies. Multidomain interventions targeting multiple risk factors simultaneously have gained increasing attention. In Japan, the J-MINT study evaluated the efficacy of a lifestyle-tailored multidomain intervention.J-MINT was an 18-month randomized controlled trial in older adults with MCI, combining exercise, nutrition, cognitive training, and management of lifestyle-related diseases. Although no significant difference was observed in the primary outcome (composite cognitive score) between intervention and control groups, participants with high adherence to exercise showed significant cognitive improvement. Subgroup analyses further demonstrated greater benefits among APOE ε4 carriers, individuals with elevated GFAP levels, and those with untreated or poorly controlled vascular risk factors, suggesting that intervention effects depend on target populations. Cost-effectiveness analysis indicated that J-MINT simultaneously reduced healthcare and long-term care costs while improving quality-adjusted life years.However, challenges for real-world implementation include the lack of evidence-based programs, shortage of trained personnel, difficulties in recruitment and retention, and the absence of sustainable business models. To address these issues, a 6-month community-based J-MINT Brain Health program, instructor certification systems, and a business framework have been developed. A cluster randomized trial across 20 municipalities is currently underway. Future efforts should focus on optimizing target populations, leveraging blood biomarkers, refining delivery methods, and elucidating mechanisms, with an emphasis on early detection and intervention.