Effectiveness of digital health interventions in improving mental health in older adults with mild cognitive impairment: A systematic review and meta-analysis

Background: Mental health challenges are common among older adults with mild cognitive impairment. Despite growing use of digital health interventions to improve cognitive function, their effects on mental health remain unexplored. Objective: To assess the overall and subgroup-specific effectiveness of digital health interventions on mental health in older adults with mild cognitive impairment. Methods: A systematic review and meta-analysis of randomized controlled trials was conducted following PRISMA guidelines, searching seven databases from inception to March 2024. Evidence quality was assessed using the GRADE framework and risk of bias with the Cochrane Collaboration's tool. Interrater agreement for screening and data extraction was assessed using the Kappa coefficient. Subgroup analyses assessed differences based on intervention characteristics such as type, setting, and duration, while meta-regression and sensitivity analysis identified other sources of heterogeneity and tested robustness. Results: Eleven studies involving 610 participants met the criteria. Digital health interventions significantly reduced depressive symptoms (Standardized Mean Difference [SMD] -0.55, 95% CI -0.92 to -0.19) and anxiety symptoms (SMD -0.47, -0.76 to -0.18), but showed no significant effects on positive (SMD 0.74, -0.46 to 1.94) or negative affect (SMD -0.23, -0.60 to 0.14). Subgroup analyses indicated that hospital or nursing home settings with non-portable modality were optimal. Interventions over 6 weeks, with sessions exceeding 30 min up to 2 per week, were more effective for depressive symptoms. Among intervention types, only robot interventions reduced depressive symptoms. Fully digital interventions showed greater effectiveness than hybrid formats and yielded more favorable outcomes compared to controls. Overall, digital health interventions showed a significant benefit over usual care, while effects compared to waitlist controls were larger but not statistically significant. Conclusions: This review indicates that digital health interventions hold promise for enhancing mental health in older adults with mild cognitive impairment. Future research should integrate digital therapeutic technologies to optimize interventions.