Frailty and healthy working life expectancy: a multicohort modelling study.

Background: Raising the retirement age and extending working years have become key strategies for many countries to mitigate the challenges of global population ageing. However, the association of frailty, a dynamic and reversible clinical condition, with healthy working life expectancy (HWLE) remains unclear. Methods: We used data from five harmonised health and retirement cohorts from across 33 countries, from which we tracked participants aged ≥50 years from baseline until their last available data point or death. Using this data, we evaluated frailty through the Frailty Index based on the cumulative deficit model, which classifies frailty status as robust, pre-frail, or frail. Then, we used discrete-time multistate Markov models to explore the association between frailty and HWLE, and further stratified our analyses by individual and country-level factors. Results: Among 180,314 participants, HWLE at the age of 50 years was 11.87 years (95% confidence interval (CI) = 11.74-12.00) for participants in the robust group, 7.34 years (95% CI = 7.19-7.50) for participants in the pre-frail group, and 3.77 years (95% CI = 3.57-3.97) for participants in the frail group. Compared with participants in the robust group, HWLE was 4.53 years shorter for those in the pre-frail group (Bonferroni-adjusted 95% confidence interval (95% CI Conclusions: While frailty was generally associated with shorter HWLE at the age of 50 years, individual and country-level inequalities were also evident across frailty statuses. These results highlight a need to integrate targeted frailty prevention and intervention programmes with broader initiatives aimed at fostering national economic and political development, thereby promoting healthier, voluntary, and supported work participation in later life.