Association between frailty and MACE and all-cause mortality in Chinese maintenance haemodialysis patients: a retrospective cohort study

BACKGROUND: Frailty is common among patients undergoing maintenance haemodialysis (MHD) and is linked to multiple adverse outcomes, including increased mortality. However, large-scale cohort studies in China on the associations between frailty and major adverse cardiovascular events (MACE) as well as all-cause mortality in patients undergoing haemodialysis are lacking. This study aimed to investigate the associations between frailty and MACE and all-cause mortality in this population. METHODS: This single-centre retrospective cohort study enrolled patients on haemodialysis at the First Affiliated Hospital, Zhejiang University School of Medicine, from August 2020 to December 2021, with follow-up until August 31, 2025. Frailty status was assessed using the Fried Frailty Scale. Endpoints included the occurrence of all-cause mortality and MACE. A competing risk model was used to examine the associations between frailty and both MACE and all-cause mortality. Additionally, multidimensional sensitivity analyses were performed to assess the robustness of the findings. RESULTS: This study encompassed a cohort of 810 patients undergoing maintenance haemodialysis (MHD). The cumulative incidence of major adverse cardiovascular events (MACE) over five years was 33.0% (95% CI: 26.1-39.8%), while the cumulative incidence of all-cause mortality was 61.0% (95% CI: 53.4-68.7%). Both incidences were significantly elevated in the frail patient group compared to their non-frail counterparts (P < 0.001). Following multivariable adjustment, the Fine-Gray competing risk model revealed that frail patients exhibited a 4.96-fold increased risk of MACE (95% CI: 2.50-9.85; P < 0.001) and a 3.35-fold increased risk of all-cause mortality (95% CI: 2.10-5.35; P < 0.001), underscoring a significant positive association. Sensitivity analyses corroborated that frailty remained significantly associated with both MACE and all-cause mortality. CONCLUSION: Frailty demonstrated a significant correlation with an increased risk of MACE and all-cause mortality in patients undergoing MHD, with the risk escalating in a linear manner in accordance with the severity of frailty.