Association between frailty assessed by the Clinical Frailty Scale 2.0 and outcomes of acute stroke in older patients

Abstract Background Frailty is a geriatric syndrome characterized by an increased vulnerability to stressors and increased risk of adverse clinical outcomes. While older patients with acute stroke are routinely screened for prestroke disability using the modified Rankin Scale (mRS), because of its known association with stroke outcomes, prestroke frailty is still rarely assessed. The Clinical Frailty Scale (CFS) is a popoular tool for retrospective frailty assessment in the acute setting. The study hypothesis was that prestroke frailty measured with CFS was associated with stroke outcome of older patients independent of prestroke disability assessed with mRS. Methods We recruited 4086 individuals aged ≥65 years consecutively admitted with acute stroke to an Italian hospital. Prestroke disability (mRS ≥3) was assessed at admission. Prestroke CFS was retrospectively assessed using information from the medical records. Logistic models determined the association of CFS with poor functional outcome, prolonged discharge, unfavorable discharge setting, and poor rehabilitation potential. Cox models determined the association of CFS with 30-day and 1-month mortality. All models were adjusted for prestroke disability and other major confounders. Results Participants were median age 81 years (25th-75th percentile, 75-87 years), 55.0% female, 82.6% with ischemic stroke, and 26.3% with prestroke disability. Overall prevalence of prestroke frailty (CFS ≥4) was 41.6%. Multivariable-adjusted logistic models showed that CFS was associated with increasing risk of all outcomes except prologed discharge. In severe frailty (CFS 7-8), OR (95%CI) was 3.44 (2.33-5.07) for poor functional outcome, 0.53 (0.38-0.75) for prolonged discharge, 1.89 (0.36-263) for unfavourable discharge, and 6.24 (3.80-10.26) for poor rehabilitation potential (reference CFS 1-3). In multivariable adjusted-Cox models, CFS was unrelated to 30-day mortality but HR (95%CI) of 1-year mortality was significant for both CFS 4-6 (1.70, 1.36-2.11) and CFS 7-8 (1.69, 1.25-2.30). Conclusions Prestroke frailty measured with CFS was associated with higher risk of several adverse outcomes even after adjustment for prestroke disability and other major confounders.