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

Frailty is increasingly recognised as a prognostic marker in cardiovascular disease, but its role in cardiogenic shock is less defined. 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. 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). 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.