Five-Year Cognitive Trajectories in Individuals with Mild Cognitive Impairment and Mild Dementia: Associations with Attendance in a Multimodal Day-Care Program

Abstract

Introduction: Mild cognitive impairment (MCI) and mild dementia are critical stages at which non-pharmacological strategies may help delay further cognitive decline. While multimodal interventions show short-term benefits, evidence on long-term cognitive trajectories, particularly regarding adherence, remains limited. We examined 5-year changes in cognitive function among individuals with MCI or mild dementia participating in a multimodal day-care program, focusing on adherence levels.

Methods: This single-arm longitudinal observational study was conducted at the University of Tsukuba Hospital (April 2013-February 2020). The multimodal program (exercise, cognitive training, music and art therapy) was conducted 3 days/week in two 2-h sessions (morning and afternoon). Most participants (approximately 94%) attended once weekly; some attended more often. Cognitive function was assessed annually using the Japanese version of the Mini-Mental State Examination (MMSE-J). Participants were grouped according to attendance thresholds (i.e., the proportion of sessions attended out of the total sessions scheduled: 50%, 60%, 70%, and 80%) to examine the association with cognitive outcomes. Mixed-effects models adjusted by propensity scores evaluated longitudinal MMSE-J changes.

Results: Among 96 participants (mean age: 71.4 years; baseline MMSE-J: 26.2; mean participation: 3.8 years), the average annual MMSE-J decline was 0.53 points (95% confidence interval [95% CI]: -0.70, -0.36). At the 60% threshold, ≥60% attendance was associated with a 2.3-point decline (vs. 6.6 points for <60%), yielding a -4.6-point difference (95% CI: -7.38, -1.73). Similar findings appeared at 70% (-4.2 points; 95% CI: -6.78, -1.55) over 5 years. No significant interactions were observed at the 50% or 80% threshold.

Conclusion: Consistent participation - attending at least 60% of sessions - in a multimodal day-care program was associated with relatively stable cognitive trajectories over 5 years, indicating the importance of sustained engagement. The findings support the potential value of continued participation and warrant further investigation in controlled settings.

Keywords: Cognitive trajectories; Mild cognitive impairment; Mild dementia; Multimodal day-care program.