The Ebetsu Active Future Study (EAFS) established a cohort of 1189 residents aged 55-75 years to track age-related physical and mental changes, finding that 53.6% of participants had operational MCI at baseline and maintaining a 98.5% follow-up rate by wave 3.
The EAFS cohort enrolled 1189 participants aged 55-75 years who were independent in activities of daily living, with a baseline year of 2023.
The EAFS cohort achieved a high follow-up rate of 98.5% by wave 3 (2025).
53.6% of EAFS participants met criteria for operational MCI as assessed by the Montreal Cognitive Assessment-Japanese (MoCA-J) at baseline.
The prevalence of APOE4 gene carriers, associated with increased Alzheimer's disease risk, was 1.2% for homozygous and 22.1% for heterozygous carriers in the cohort.
The EAFS protocol includes comprehensive annual assessments covering cognitive function, physical function, blood tests, questionnaires, and biological sample storage.
The Ebetsu Active Future Study (EAFS) is a long-term research project based in Ebetsu City, Japan, that is following nearly 1,200 adults aged 55 to 75 over multiple years to understand how physical and mental health change with aging. At the study's start in 2023, participants underwent a comprehensive set of tests including memory and thinking assessments, physical fitness evaluations, blood draws, and questionnaires about their lifestyle and health history. Blood and DNA samples are being frozen and stored for future research. Notably, the study has maintained an exceptionally high follow-up rate of 98.5% through its third wave in 2025, meaning nearly all participants are continuing to take part. One of the most striking findings from the baseline assessment is that over half of participants (53.6%) showed signs of what the researchers call 'operational mild cognitive impairment' (MCI) based on a standard cognitive screening tool, and this proportion increased among older participants. The study also found that about 22% of participants carry one copy of the APOE4 gene variant, which is linked to higher Alzheimer's disease risk, and about 1% carry two copies. These findings highlight how common early cognitive concerns are in this age group. This research suggests that community-based studies like EAFS can successfully track a large number of older adults over time with very low dropout rates. The stored biological samples and detailed health records will allow researchers to investigate whether certain markers in the blood can detect early cognitive decline, and whether specific dietary habits might slow or prevent the development of dementia. The study is planned to continue through 2032, and findings are intended to be shared back with the local community to inform public health planning.
Kagami-Katsuyama H, Ito N, Hazama M, Toya N, Wataya T, Satoh K, et al.. (2026). Ebetsu Active Future Study (EAFS): cognitive function and physical and mental health in elderly residents of Ebetsu City, Japan - cohort profile.. BMJ open. https://doi.org/10.1136/bmjopen-2026-118786