Featured Article| Volume 223, ISSUE 5, P857-862, May 2022

Decreases in daily ambulation forecast post-surgical re-admission


      • A gap in knowledge exists in identifying hospital readmissions prior to their occurrence.
      • Measurement of daily walking represents a novel form of health telemetry.
      • A decrease of >50% daily ambulation over two days forecasts hospital readmission.
      • This finding represents a novel form of outpatient telemetry (tracking outpatient ambulation).



      Surgical readmissions are clinically and financially problematic. Our purpose is to determine if a decrease in postoperative ambulation (steps/day) is associated with hospital readmission.


      In this prospective cohort study, patients undergoing elective operations wore an accelerometer activity tracker to measure steps/day for 28 consecutive postoperative days. The primary outcome was hospital readmission. The change in steps/day over two consecutive days prior to the day of the readmission were examined. Predetermined thresholds for decreases of consecutive daily ambulation levels were used to calculate sensitivity and specificity for the outcome of hospital readmission.


      215 patients (aged 63 ± 12 years) were included. Readmission occurred in 10% (n = 21). For each of the first 28-postoperative days, the entire cohort had an average daily step increase of 136 ± 146 steps/day (Spearman correlation rho = 0.990; p < 0.001). A decrease in steps for two consecutive days of >50% from the prior day had a 79% sensitivity and 90% specificity for hospital readmission.


      A decrease of >50% daily ambulation (steps/day) over two consecutive post-discharge days accurately forecasts hospital readmission. The implications of these findings are that monitoring daily ambulation could serve as a form of outpatient telemetry aiding to forecast post-surgical readmissions.


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