The concept of dynamic frailty: an exploratory study of the trajectory to postoperative mortality

Frailty is a heightened vulnerability to stress due to decreased physical and mental abilities. Preoperative frailty has been associated with poorer outcomes. However, frailty is not static, and those patients who eventually die appear to become more frail. Our hypothesis is in-patient, postoperative changes in frailty after major operations predicts the trajectory to postoperative discharge alive or in-hospital mortality.

The accumulating deficit model of frailty was used. Data from the medical records of patients who have undergone major operations were used to determine the mFI preoperatively, postoperative day 1, and day before discharge or death. Of the 1063 patients who met inclusion criteria, 50 patients with in-hospital postoperative death and 50 patients discharged alive were randomly selected.

Patients in the in-hospital mortality group had significantly greater median preoperative mFI scores than those in the discharged alive (0.178 vs. 0.115 p = 0.00009). This significant difference was present on postoperative day 1, while also increasing in margin (0.240 vs. 0.143, p < 0.00001). Median Pre-Post mFI differences were also significant between the two groups, with operations leading to in-hospital mortality experiencing a greater increase in mFI (0.06 vs. 0.01 p = 0.00019), and the day before death or discharge (0.276 vs. 0.014, p < 0.00001).

Preoperative mFI is a useful predictor of postoperative mortality. Moreover, worsening mFI score as early as day 1 and continued worsening scores throughout hospitalization are associated with a postoperative trajectory toward mortality. Recognition of worsening frailty may be helpful in identifying patients in need of early intervention.