Association of psychological factors with advanced-level functional competency: Findings from the Aichi workers’ cohort study, 2002–2019

Objective: This study examined the longitudinal association of perceived stress, ikigai, and having someone one can count on in middle age with the advanced-level functional competency in older age, which is crucial for the maintenance of independent life among older adults. The issue is especially relevant in super-aged countries like contemporary Japan, where more and more older people live in a household consisting only of older people. Methods: Data were collected in 2019 from a total of 1692 retirees of the Aichi Workers’ Cohort Study participants in which baseline survey including psychological factors was conducted during their employment in 2002. Japan Science and Technology Agency Index of Competence (JST-IC) was used to measure the advanced-level functional competency. Multivariable-adjusted odds ratios (ORs) were obtained for having low JST-IC in later life by the degrees of psychological factors reported in the middle age adjusting for the presence of depressive mood in 2019. Results: Those who were not sure about ikigai (OR: 2.02, 95 % CI: 1.33 to 3.08) and who have no one to count on (OR: 2.19, 95 % CI: 1.52 to 3.16) in the middle age were significantly associated with low JST-IC after retirement. Having much stress was significantly inversely associated with a low JST-IC (OR: 0.69, 95 % CI: 0.50 to 0.97). Conclusion: Having ikigai and someone reliable, and stress during middle age might play a role in preventing impaired advanced-level functional competency. Improved ikigai and increased social interaction and support might improve functional competency. Further research might explore avenues for improving ikigai.