Validation of the hospital frailty risk score in China.

Purpose: To validate the Hospital Frailty Risk Score (HFRS) in Chinese hospital settings, describing how patients are allocated to frailty risk groups and how frailty risk is associated with length of stay (LoS) and hospital costs.

Design: Retrospective observational study.

Setting: Forty-eight hospitals in Lvliang City, Shanxi Province, China.

Subjects: Patients aged 75 years or older hospitalised between 1 January 2022 and 31 December 2023 (n = 34,731).

Methods: A logistic regression model examined the association between long length of stay (LoS) and frailty risk. A generalised linear model assessed the association between hospital costs and frailty risk. Subgroup analyses of age group, sex, and hospital tiers were conducted.

Results: 22.2% of patients were categorised as having zero risk, 62.4% as low risk, 15.3% as intermediate risk, and 0.08% as high risk. Compared to the zero risk group: for those with low risk, the probability of long LoS was 1.92 (95% CI 1.79-2.06) times higher and hospital costs were ¥1926 (95% CI 1655-2197) higher; for those with intermediate risk, the probability of long LoS was 2.7 (95% CI 2.49-2.96) times higher and hospital costs were ¥4284 (95% CI 3916-4653) higher; and for those with high risk, the probability of long LoS was 6.7 (95% CI 3.06-14.43) times higher and hospital costs were ¥16,613 (95% CI 12,827-20,399) higher. The explanatory power of the HFRS held across subgroups.

Conclusions: Compared to patients aged 75 + elsewhere, those in China had lower frailty risk scores, likely reflecting a younger age structure and recording of fewer diagnosis codes. Even so, the HFRS is a powerful predictor of long length of stay and hospital costs in China.