Retrospective Cohort Study in Two UK Regional Vascular Centres to Investigate the Effect of Frailty on Death following Lower Limb Amputation

OBJECTIVE: The study aimed to demonstrate the long term relationship between frailty, death and discharge following major limb amputation (MLA) for chronic limb threatening ischaemia. The primary outcome was death at five years, and the secondary outcome was length of stay (LOS) following MLA. METHODS: A retrospective, multicentre, long term cohort study of MLA was performed between 2016 and 2021. Data were obtained from a prospectively collected database. Patients were assessed for frailty (Clinical Frailty Scale [CFS]) and categorised as not frail (CFS score 1 - 3), living with mild frailty (CFS score 4 - 5), and living with moderate or severe frailty (CFS score 6 - 8). CFS was calculated retrospectively from the electronic medical records. In the primary analysis, pre-operative data were adjusted for site, age, amputation level, Charlson comorbidity index, and indices of multiple deprivation. A Cox proportional hazards regression was used. RESULTS: A total of 823 patients were included: 17% were not frail, 53% were living with mild frailty, and 30% were living with moderate to severe frailty. Survival rates at one and five years were 91.0% (95% confidence interval [CI] 85 - 95%) and 57.0% (95% CI 46 - 66%) for those not frail, 77.0% (95% CI 73 - 81%) and 37.0% (95% CI 32 - 42%) for those with pre-operative mild frailty, and 59.0% (95% CI 52 - 65%) and 18.0% (95% CI 13 - 24) for those with moderate or severe frailty, respectively. Pre-amputation frailty, site, Charlson comorbidity index, and age were prognostic factors (all p < .001). There was no relationship between pre-operative frailty and LOS. CONCLUSION: Frailty was associated with death following MLA, but not LOS. A patient's frailty status should be part of the shared decision making process.