mHealth Physical Activity and Patient-Reported Outcomes in Patients With Inflammatory Bowel Diseases: Cluster Analysis
Authors: Griffin Ashley C , Mentch Lucas , Lin Feng-Chang , Chung Arlene E 
Published: July 2024

Background
Regular physical activity is associated with improved quality of life in patients with inflammatory bowel diseases (IBDs), although much of the existing research is based on self-reported data. Wearable devices provide objective data on many rich physical activity dimensions including steps, duration, distance, and intensity. Little is known about how patients with IBDs engage in these varying dimensions of exercise and how it may influence their symptom and disease-specific patient-reported outcomes (PROs).

Objective
This study aims to (1) cluster physical activity patterns from consumer-grade wearable devices and (2) assess the relationship between the clusters and PROs in patients with IBDs.

Methods
We conducted a cross-sectional and longitudinal cohort study among adults with IBDs in the Crohn’s and Colitis Foundation IBD Partners cohort. Participants contribute physical activity data through smartphone apps or wearable devices in a bring-your-own-device model. Participants also complete biannual PRO questionnaires from the Patient-Reported Outcomes Measurement Information System short forms and IBD-specific questionnaires. K-means cluster analysis was used to generate physical activity clusters based on 3 key features: number of steps, duration of moderate to vigorous activity (minutes), and distance of activity (miles). Based on the clusters, we conducted a cross-sectional analysis to examine differences in mean questionnaire scores and participant characteristics using one-way ANOVA and chi-square tests. We also conducted a longitudinal analysis to examine individual cluster transitions among participants who completed multiple questionnaires, and mean differences in questionnaire scores were compared using 2-tailed paired sample t tests across 6-month periods.

Results
Among 430 participants comprising 1255 six-week physical activity periods, we identified clusters of low (33.7%, n=423), moderate (46%, n=577), and high (20.3%, n=255) physical activity. Scores varied across clusters for depression (P=.004), pain interference (P<.001), fatigue (P<.001), sleep disturbance (P<.001), social satisfaction (P<.001), and short Crohn Disease Activity Index (P<.001), with those in the low activity cluster having the worst scores. Sociodemographic characteristics also differed, and those with low physical activity were older (P=.002), had higher BMIs (P<.001), and had longer disease durations (P=.02) compared to other clusters. Among 246 participants who completed at least 2 consecutive questionnaires consisting of 726 questionnaire periods, 67.8% (n=492) remained in the same cluster, and only 1.2% (n=9) moved to or from the furthest clusters of low and high activity across 6-month periods.

Conclusions
For patients with IBDs, there were positive associations between physical activity and PROs related to disease activity and psychosocial domains. Physical activity patterns mostly did not fluctuate over time, suggesting little variation in exercise levels in the absence of an intervention. The use of real-world data to identify subgroups with similar lifestyle behaviors could be leveraged to develop targeted interventions that provide support for psychosocial symptoms and physical activity for personalized IBD care.