Frailty Index Associated with All-cause Mortality, Long-term Institutionalization, and Hip Fracture

Purpose: To assess the association between frailty, measured using a frailty diagnosis tool, and adverse outcomes using regular health checkup data and National Health Insurance claim data of 66-year-old Koreans.

Methods: We evaluated all Koreans born between 1942 and 1946 who received a 66-year lifetime transition period health examination and regular biennial general and cancer screenings between 2008 and 2012. These patients were observed until December 31, 2015. The Lifetime Transition Period Health Examination version of the Korean Frailty Index (THE frailty index) was used to examine adverse geriatric outcomes based on levels of frailty. THE frailty index scores were used to classify participants as "robust" (0-2), "pre-frail" (3-4), or "frail" (more than 5). The main outcomes included the risks of all-cause mortality, long-term care facility institutionalization, and hip fracture.

Results: Among 725,759 Korean men and women, the prevalence of frail and pre-frail conditions was 3.4% and 26.6%, respectively. After an average of 4.4 years of follow-up, frail older persons had significantly higher mortality rates [men: hazard ratio (HR) 2.031 (95% confidence interval [CI], 1.894-2.178); women: HR 2.092 (95% CI 1.920-2.279)], long-term care facility institutionalization [men: HR 2.997 (95% CI 2.750-3.268); women: HR 3.057 (95% CI 2.866-3.261)], and hip fracture [men: HR 2.230 (95% CI 1.854-2.681); women: HR 2.356 (95% CI 2.086-2.660)] than those of robust older persons.

Conclusions: Aged frail persons diagnosed using the THE frailty index had higher all-cause mortality, more frequent entry into long-term care facilities, and greater risk of hip fracture.