Frailty and long-term mortality in cardiogenic shock: a binational multicentre cohort study.

BACKGROUND: Frailty is increasingly recognised as a prognostic marker in cardiovascular disease, but its role in cardiogenic shock is less defined. METHODS: In this retrospective cohort study across 188 intensive care units (ICUs), we analysed data from the Australia and New Zealand Intensive Care Society Adult Patient Database on adults (≥ 16 years) with admitted with cardiogenic shock between 2017–2023, and a documented Clinical Frailty Scale (CFS). The primary outcome was death at up to four years using an adjusted Cox proportional hazards model, which we also assessed using a time-varying model. We conducted subgroup analyses based on age, sex, aetiology of cardiogenic shock, and a landmark survival analysis at ICU discharge. RESULTS: We included 71,359 patients (median age 68.6 years, 70.0% males); 11,087 had frailty. Frailty was associated with a higher hazard of death (adjusted Hazard ratio [aHR]: 2.27, 95% confidence interval [CI]: 2.05–2.51) in a non-linear incremental fashion; this was consistent across sensitivity analyses. Time-varying analysis found that frailty demonstrated the highest hazard for death at approximately six months post-ICU admission (HR: 3.71, 95%-CI: 3.29–4.18). Frailty was more strongly associated with death in patients with ischaemic than non-ischaemic cardiogenic shock, and in males more than females. Frailty was also associated with death in a landmark survival analysis at ICU discharge (aHR: 3.13, 95%-CI: 2.82–3.48). CONCLUSIONS: Frailty is associated with mortality beyond ICU discharge in cardiogenic shock in a non-linear, stepwise fashion. These findings support the integration of frailty assessment into ICU risk stratification and post-discharge care planning.