Healthy aging predicts mortality risks: Results from the Korean longitudinal study of aging (2006-2014)

Introduction: While there has been some gerontological research on healthy aging, few studies have identified a reasonable health status for the older adults. Guided by the four healthy aging concepts in studies from the US and Spain, this study sought to determine a useful definition for Korean older adults by examining the associations between each of the four healthy aging definitions and mortality. Methods: A longitudinal analysis was conducted based on the 2,960 older people (65 years or older) who participated in the Korean Longitudinal Study of Aging (2006-2014). Four healthy aging gradient definitions (Rowe and Kahn, Group I, Group II, and Group III) were determined: absence of disease, free of disability, physical and cognitive function, and engagement with life. Results: The young old who failed to achieve healthy aging were found to have a higher risk of mortality in all four healthy aging gradient definitions in both males (HR range from 4.15 to 5.39) and females (HR range from 4.07 to 9.55). In old old, however, the unhealthy aging mortality risk in Rowe and Kahn's definition was disappeared, but predominant mortality risks were found in Group III for both male (HR = 3.16, 95% CI 1.67 - 5.98) and female (HR = 3.65, 95% CI 1.36 - 9.81) Conclusion: To promote healthy aging, we suggest that the definition for the young old includes rigid disease criteria, and old old emphasize functional ability. Age-specific aims for healthy aging may be useful for defining healthy aging.