Stronger Association of the Japanese Cognitive Function Test Than the Mini-Mental State Examination With Mortality in...

Cognitive function is associated with mortality in older adults, but the relative strength across cognitive assessment tools remains unclear, complicating population-level risk screening. The Mini-Mental State Examination is widely used but is limited by ceiling effects and educational bias. This study compared the associations of Mini-Mental State Examination and the Japanese Cognitive Function Test, a digital assessment, with all-cause mortality in a community-based cohort.

A cohort study was conducted among older adults in the National Center for Geriatrics and Gerontology-Study of Geriatric Syndromes in Japan. Participants aged ≥65 years completed the Mini-Mental State Examination and Japanese Cognitive Function Test at baseline during 2015-2018; data were analyzed in 2025. Cox proportional hazards models estimated hazard ratios for mortality, with exposures analyzed as both continuous and categorical variables. The duplication method tested the differences between the 2 tests.

Among 9,514 participants (mean age of 72.9; 55% female), 588 (6.2%) died. Higher scores on both tests were inversely associated with mortality, but the associations were stronger for Japanese Cognitive Function Test. In continuous analyses, adjusted hazard ratios were 0.64 (0.54-0.77) for Mini-Mental State Examination and 0.44 (0.36-0.55) for Japanese Cognitive Function Test (p<0.001). In quintile analyses, hazard ratios for the highest versus the lowest quintile were 0.70 (0.52-0.93) and 0.37 (0.26-0.54). Stronger associations for Japanese Cognitive Function Test were more pronounced among participants with preserved baseline cognition (Mini-Mental State Examination≥24).

Mini-Mental State Examination and Japanese Cognitive Function Test were inversely associated with 5-year mortality, but the association was stronger for Japanese Cognitive Function Test. Japanese Cognitive Function Test captured mortality risk even among those with preserved cognition, supporting its potential as a community-level tool for public health in older adults.