Assessing pre- and postoperative activity levels with an accelerometer: a proof of concept study

BACKGROUND Postoperative recovery after abdominal surgery is measured mostly based on subjective or self-reported data. In this article we aim to evaluate whether recovery of daily physical activity levels can be measured postoperatively with the use of an accelerometer. METHODS In this multicenter, observational pilot study, 30 patients undergoing laparoscopic abdominal surgery (hysterectomy, adnexal surgery, cholecystectomy and hernia inguinal surgery) were included. Patients were instructed to wear an Actigraph wGT3X-BT accelerometer during one week before surgery (baseline) and during the first, third and fifth week after surgery. Wear time, steps taken and physical activity intensity levels (sedentary, light, moderate and vigorous) were measured. Patients were blinded for the accelerometer outcomes. Additionally, an activity diary comprising patients' self-reported time of being recovered and a list of 18 activities, in which the dates of resumption of these 18 activities were recorded after surgery, was completed by the patient. RESULTS Five patients were excluded from analyses because of technical problems with the accelerometer (n = 1) and protocol non-adherence (n = 4). Light, moderate, vigorous, combined moderate and vigorous intensity physical activity (MVPA), and step counts showed a clear recovery curve after surgery. Patients who underwent minor surgery reached their baseline step count and MVPA three weeks after surgery. Patients who underwent intermediate surgery had not yet reached their baseline step count during the last measuring week (five weeks after surgery). The results of the activity diaries showed a fair agreement with the accelerometer results (Cohens Kappa range: 0.273-0.391). Wearing the accelerometer was well tolerated and not regarded as being burdensome by the patients. CONCLUSIONS The accelerometer appeared to be a feasible way to measure recovery of postoperative physical activity levels in this study and was well tolerated by the patients. The agreement with self-reported physical recovery times was fair.