Frailty and delirium are associated with delayed early postoperative mobilisation in older patients with hip fracture

Background Early mobilisation after hip fracture is a known predictor of short- and long-term outcomes. We investigated factors associated with reduced mobilisation in older patients with hip fracture. Methods The study population included 430 patients with hip fracture (70 years or older, 69% women and 61% with an intracapsular fracture) between September 2021 to January 2023. The degree of mobilisation was recorded during the early postoperative period using the Cumulated Ambulation Score (CAS). Multivariable logistic regression analyses were used according to the combined CAS scores of postoperative days 1, 1–2, and 1–3. Fracture type, delirium (4AT test), the Clinical Frailty Scale (CFS) scores, and nutritional status (Mini Nutritional Assessment Short Form (MNA-SF) adjusted for six confounding factors, were the explanatory variables. Results In all three postoperative CAS scores severe frailty (CFS7–9) versus CFS1-3 was associated with lower mobilisation (adjusted Odds Ratio, OR = 5.01, Confidence Interval, 95%CI, 1.61–15.63; OR = 24.92, 95%CI, 2.78-223.47, and OR = 62.88, 95%CI, 6.32–625.70, respectively), and mild-to-moderate frailty (CFS4–6) only in the 2-day CAS (OR = 2.14, 95%CI, 1.07, 4.26). Possible delirium (4AT > 3p) versus no delirium was associated with lower mobilisation in the 1-day CAS (OR = 2.45, 95%CI, 1.23–4.91) and in the 3-day CAS (OR = 2.85, 95%CI, 1.20–6.79). Malnutrition (MNA-SF) did not show association with mobilisation in any of the CAS scores. Conclusion Frailty and delirium were associated with lower postoperative mobilisation in patients with hip fracture. Frailty and prevention of delirium should be given specific attention in the perioperative care of older patients with hip fracture to improve their early ambulatory status. Trial registration The study has been registred locally by the Turku Clinical Research Center, Turku, Finland (study number T145/2021).