{'fraction_non_alphanumeric': 0.025872067088946384, 'fraction_numerical': 0.014185029886698189, 'mean_word_length': 5.15934065934066, 'pattern_counts': {'":': 0, '<': 1, '<?xml version=': 0, '>': 2, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Supervised preoperative walking on increasing early postoperative stamina and mobility in older adults with frailty traits: A pilot and feasibility study

Abstract Background and Aims Frail older adults are more than twice as likely to experience postoperative complications. Preoperative exercise may better prepare these patients through improved stamina and mobility experienced in the days following surgery. We measured the impact of a walking intervention using an activity tracker and coaching on postoperative stamina, and mobility in older adults with frailty traits. Methods We included patients aged 60+ and scoring 4+ on the Edmonton Frailty Scale. We then randomized patients to intervention versus control stratified by anticipated hospital stay (1 night vs. 2+ night) and baseline stamina (i.e., 6‐min walk distance [6MWD]). Intervention patients received an activity tracker and linked smart phone. An athletic trainer (AT) prescribed a daily step count goal and titrated this up after checking in with patients during weekly telephone calls. Controls received general walking recommendations. We then measured postoperative 6MWD 1–3 days after surgery. We also assessed postoperative mobility by measuring steps walked the day after surgery using a thigh‐worn monitor. Because many patients could not walk postoperatively, we compared intervention‐control difference in both 6MWD and steps using Wilcoxon rank testing and Tobit and ordinal logistic regression adjusting for several patient characteristics. Results We randomized 104 eligible patients; 80 patients remained for final analysis. There was no difference in intervention versus control postoperative 6MWD (median 72 vs. 74 m Wilcoxon p = 0.54) or postoperative steps taken (median 128 vs. 51 steps Wilcoxon p = 0.76). Analysis adjusting for patient characteristics was consistent with these findings. Conclusion Our intervention consisting of goal setting with an activity tracker and telephonic coaching by an AT did not appear to improve stamina or mobility measured in the days after surgery. Small sample size limited our ability to examine this impact in subsets defined by surgical specialty or baseline stamina.


| INTRODUCTION
When compared against their nonfrail counterparts, frail older adult surgical patients have more than a twofold increased risk for postoperative complications, including deep vein thrombosis, renal failure, stroke, deep wound infection, and pneumonia. 1,2 Older adults with frailty traits represent individuals having several of the features and vulnerability of complete syndrome of frailty defined further below in Section 2. As adults age, many lose proprioception, muscular strength, and visual perception. Together these deficits lead to a more sedentary lifestyle. This sedentary lifestyle exacerbates lower extremity muscle weakness which manifests as decreased physical activity, stamina, and mobility. 3 Preoperative exercise, or prehabilitation, may be a feasible solution to improve patient stamina and mobility. Previous interventions have required costly in-person therapy sessions and focused on general surgical patients and not frail older adults. [4][5][6] They also did not include goal setting with a modern pedometer or remote coaching. Prior studies also focused on outcomes collected 4 weeks or longer after surgery, a point at which significant variation in rehabilitation, nursing, and other services has taken place. [5][6][7] In this brief report, we present the results of a pilot study to assess the impact of a preoperative walking intervention using goal setting with a modern pedometer and telephonic coaching on early, that is, in-hospital, postoperative stamina, and mobility in older adults with some or all of the frailty traits.

| METHODS
We previously described our methods but will summarize the main features below. 8

| Population
We screened surgery request orders and appointment logs of patients aged 60 and older seeing surgeons from specialties participating in our study. Specialties participating included colorectal, thoracic, urological, transplant, oncological, and vascular surgery. Once we identified potentially eligible patients, we approached them at a visit with their surgeon or by telephone. We then consented them to participate and screened them for frailty using the Edmonton Frailty Scale (EFS). Those scoring 4 or higher on the EFS were eligible to participate in the randomized trial of our intervention. Scores of 8 or higher typically define the full frailty syndrome but previous research suggests that patients scoring 4 or higher, that is, older adults with frailty traits, are also vulnerable to postoperative complications. 9 To have sufficient time to intervene and also standardize the intervention, we restricted enrollment to patients for whom the anticipated surgery date was at least 3 but not more than 8 weeks from time of enrollment.

| Randomization
We randomized patients in 1:1 fashion to receive our intervention versus general walking instructions stratified on anticipated length of stay and baseline stamina grouped into four categories (<200, 201-300, 301-400, and >400 m).

| Intervention and control procedures
To intervention patients, we issued a wrist worn pedometer, a Garmin Vivofit 4, and a linked smart phone with cellular connectivity.
Through these devices, an athletic trainer reviewed baseline activity, prescribed a daily step count goal, and then titrated up the goal during weekly check-in calls. For controls, we provided general recommendations to stay active and walk before surgery.

| Postoperative stamina
We evaluated stamina and mobility in the days after surgery.
Prior studies have not measured recovery in frail older adults in the days following surgery. We selected this phase of care because it avoids confounding by heterogeneity in post-acute care rehab and other services. For patients whose stay was anticipated to last two or more nights, we measured 6MWD on the second postoperative day (POD2). If the patient was unable, we re-attempted on POD3. For patients staying only one night, we measured 6MWD on POD1. For any patient unable to walk after these attempts, we assigned a 0 as their postoperative 6MWD.

| Postoperative mobility
For postoperative mobility, we compared intervention and control patients for steps walked from 9:00 a.m. to 5:00 p.m. on POD1 using the ActivPal3, a thigh-worn research grade accelerometer. 10 For patients for whom the full 8 hour was not available (such as those discharged early on POD1), we projected number of steps they walked based on their hourly average. We also analyzed the adherence and preoperative step counts of intervention patients.
Specifically, we calculated the percentage of days that the patients met their step count goal as well as the change in the average daily step count that they walked in the first 3 days of wearing the wrist pedometer (baseline assessment period) compared with the week leading up to surgery.

| Postoperative loss of stamina
We also examined loss of stamina (Δ6MWD) as the difference between baseline and postoperative 6MWD. We elected not to make loss of stamina our primary outcome given the ambiguous significance and difficulty analyzing values for patients unable to walk postoperatively.

| Covariates
Covariates included patient characteristics (i.e., age, gender, race/ ethnicity, frailty score as measured by the EFS, specialty of surgery performed, baseline 6MWD, days elapsed from randomization to surgery, anticipated length of stay, and American Society of Anesthesiologists classification).

| Sample calculation and analysis
Applying 80% power with 5% type I error rate for two-sided hypothesis testing and using a standard deviation of 48 m for normally distributed within-patient Δ6MWD found in Gillis et al., 5 we originally computed that we would need follow-up outcome data on 40 patients per treatment arm to detect a mean betweengroup difference in Δ6MWD of 30.5 m (0.63 effect size). Because several patients could not walk for the postoperative 6MWD measurement when approached, yielding a nonnormal distribution, we assessed the intervention-control difference using Wilcoxon rank testing. We also assessed the difference using covariateadjusted analyses following the Tobit approach 11 and ordinal logistic regression. For the ordinal regression, we grouped patients into three distance categories 0, 1-100, and >100 m. We followed a similar procedure for our postoperative step outcome. For our secondary outcome, that is, loss of stamina, we examined the distribution of values. Given these values followed a normal distribution as described in Section 3, we constructed a linear regression model adjusting for covariates.

| Descriptive
We identified and randomized 104 eligible patients. Twenty-four patients did not undergo surgery, withdrew, or were not available for outcome assessment. Eighty patients remained for analysis. (Figure 1).   In terms of the adherence, we found few intervention patients consistently met their daily step counts with mean F I G U R E 1 CONSORT flow diagram. *Measured on second or third postoperative day (POD2 or POD3) for patients that stayed 2+ nights. For patients staying one night, we measured 6MWD on POD1. **Step counts walked 9:00 a.m. to 5:00 p.m. on POD1. 6MWD, 6-min walk distance; CONSORT, consolidated standards of reporting trials.

| Postoperative mobility
percentage of days where a patient met their goals equaling 41% ± standard deviation of 17%. Despite this, intervention patients improved their average daily step count by 879 ± standard deviation of 1720 from beginning to end of the intervention.   absence of a significant increase in postoperative stamina and mobility. Outside of the perioperative context, studies exist that support longer duration and resistive training. 12,13 In many cases, it would be infeasible to delay surgery more than 8 weeks. Further pilot study of the duration and acceptability of a longer training period would be informative in planning larger trials. The absence of impact on postoperative stamina and mobility for our intervention occurred despite significant improvements in physical activity. We did not monitor preoperative step counts in control patients, but it is possible that they also improved physical activity. Because we did not have preoperative step counts for control patients, we could not measure between group difference in change in step counts from baseline to after surgery. Equipping controls with activity trackers to capture these counts may have unduly encouraged them to walk more.

| Postoperative loss of stamina
At the time of our study, there was no significant alternative exercise program recommended for participants. We are unaware of any studies looking at improvements in physical activity based on general recommendations such as those provided to our control patients.
In conclusion, our intervention consisting of goal setting with an activity tracker and telephonic coaching did not appear to have an impact on stamina or mobility measured in the days after surgery. Small sample size limited our ability to examine this