Introduction In 2006, the Japanese government introduced a new prevention policy to limit the growth of old age disability care. The policy is based on what Geoffrey Rose called the “high-risk strategy” of prevention, and seeks to identify individuals with multiple risk factors. We provide cohort data to examine the feasibility of the policy.

Methods Older people (≥65 years old, n=11 889) who were independent in activities of daily living were followed up for 3 years as a part of AGES (Aichi Gerontological Evaluation Study) project. The endpoint is becoming functionally dependent. We used eligibility criteria for public long-term care insurance policy.

Results At baseline, 63% of subjects had no risk factors and 3% had three or more risk factors (high-risk group, HRG). After 3 years, 1149 individuals become dependent. Among the HRG, 32% lost independence compared to 6% of those with no risks. Although the HRG showed a higher rate of functional decline, they only comprised 9% of those who became dependent. If the targeted population is expanded to those with one or more risk factors, 57% of dependent people become eligible but the number requiring surveillance rises to more than ten million individuals in the country, with substantial costs of screening.

Conclusion The majority of cases of disability arises among individuals with fewer risk factors, illustrating Rose's principle of the prevention paradox. Pursuing the high-risk strategy results in lower coverage, as well as substantial costs of screening. This suggests that a population strategy is the only sustainable approach.