Frailty transition and burden on mortality risk in middle-aged and older population: a prospective cohort study

The effect of frailty transition and burden on the risk of all-cause mortality in South Korea remains unclear. This study aimed to investigate the risk of all-cause mortality using the most recent frailty index (FI), changes in FI, and frailty burden. We analyzed data from the Korean Genome and Epidemiology Study (2013-2020). A total of 3,134 participants aged 53-87 years with a computable FI based on the osteoporotic fracture index during their initial visit. The FI was updated biennially during re-examinations and changes between the initial and last visits were categorized into four groups: (1) improved or maintained to non-frail, (2) worsened to pre-frail, (3) improved or maintained to pre-frail, and (4) worsened or maintained to frail. We used the Cox proportional hazards model, adjusted for age, sex, education, lifestyle factors, and diseases. During the follow-up, 218 participants died. Compared to those who were robust at the last visit, pre-frailty and frailty were associated with an increased risk of all-cause death. Of those who visited > 2 times, 62.3% improved or remained robust, and had a decreased risk of all-cause death. Those with > 63% of pre-frailty or frailty burden significantly higher risk of death, with > 60% increase compared to their non-frail counterparts. Maintaining or achieving robustness is associated with a decreased risk of mortality. To prevent premature death and extend healthy life expectancy, identifying biological aging through surrogate measures and implementing interventions to maintain or achieve a robust health status are needed.