In patients with kidney disease on hemodialysis, a wearable activity tracker paired with a feedback intervention increased daily step count over 12 weeks.
Studies have shown that patients receiving maintenance hemodialysis (HD) for advanced kidney disease can improve their morbidity and mortality through regular physical activity. Through the advent of digital technology to monitor steps and other forms of exercise, the opportunity to improve physical activity in patients with advanced and end-stage kidney disease seems promising.
A Tracker to Improve Physical Activity
An assessment of the potential of these digital tracking devices to spur real improvement has been limited. Furthermore, a comparison between the success of applying a digital tracker alone versus a digital tracker and feedback intervention warrants review. To address this gap in knowledge, Rakesh Malhotra, MD, MPH, and colleagues conducted a 12-week, unmasked, randomized controlled pilot trial to compare the positive impact of a wearable tracker device alone versus a wearable tracker device along with regulated feedback in patients with advanced kidney disease receiving HD. Their findings were published in the American Journal of Kidney Disease.
“We hypothesized that, equipped with activity data, sequentially informing the participants quantitatively about their levels of physical activity relative to other patients receiving HD would promote greater physical activity in this high-risk population,” Dr. Malhotra and colleagues wrote.
80% of Study Patients Had Hypertension
A total of 55 patients were enrolled in the study, of whom 46 completed the 12-week intervention. The patients were randomly assigned into two groups—a group that used the digital tracker alone (n=28 [4 incomplete]; DT) and a group that used the digital tracker plus structured feedback (n=27 [5 incomplete]; DT-F). The study population comprised patients with mean age of 62±14 years, 27 (49%) women, 24 (44%) Black patients, and 20 (36%) Hispanic patients. Hypertension was prevalent in 80% of patients (n=44), and 62% (n=34) had a diabetes diagnosis. The mean length of time on dialysis was 4.7±2.4 years. On average, the patients recorded 3,755±1,730 mean (SD) steps per day in the week before they were assigned into either cohort.
The primary outcome of the study was the change in step count. Both cohorts received thorough instruction on how to use the digital tracker (ie, Fitbit Charge 2), including how to use the corresponding Fitbit app and website. Patients were instructed to always wear the device except during bathing and recharging, which occurred when patients received medical treatment that would have prevented physical activity.
More Steps Logged by the Feedback Group
Patients in the DT-F group experienced a statistically significantly greater increase in the number of steps logged from the start of the study to week 12 compared with patients in the DT group (920±580 vs 281±186; between-group difference delta, 639 [±538 SD] steps; P<0.05) (Table). An increase in the number of steps was most pronounced in the first 4 weeks in the DT-F group compared with the DT group. The variation in total steps between the two groups remained statistically significant throughout the study but tapered off as the study progressed.
“Our findings demonstrate that a face-to-face feedback intervention is feasible and can meaningfully increase step count in patients receiving HD,” the study authors wrote. “The 639 additional steps in the intervention arm were around 17% more steps per day than observed in the comparator arm. This may have important downstream health implications: changes of this magnitude have been associated with standardized risk reductions of approximately 3% to 4% in cardiovascular events and 4% to 6% in mortality in other populations.”
The researchers are hopeful that additional studies will further examine the potential for positive outcomes as a result of combined digital and face-to-face interventions to improve physical activity in patients with kidney disease undergoing HD.
