Stress-Symptom Interaction in Inflammatory Bowel Disease: Longitudinal Digital Phenotyping Study

Stress and inflammatory bowel disease (IBD) symptoms may vary over short time scales, but these dynamics are not well captured by intermittent clinical assessments.

The study aimed to characterize exploratory time-varying stress-symptom patterns using intensive longitudinal monitoring and to evaluate a transparent, patient-clustered analysis framework.

A prospective longitudinal design was used with 74 patients with IBD monitored for 90 days. Daily data comprised 12 core indicators and 2 auxiliary measures. The canonical analysis used patient-level partial-correlation PCMCI (Peter and Clark Momentary Conditional Independence) with a τ of 0 to 2, patient-specific network scaling, a fixed 30-day cycle-end stress contrast, exploratory module-control, and effective-information summaries, and a secondary exploratory time-varying effect model (TVEM).

Mean stress was higher during cycle days 26 to 30 (mean 4.789, SD 1.079) than during nonwindow days (mean 4.160, SD 1.013), with a mean within-person difference of 0.629 (95% CI 0.550-0.708; P<.001); 71 of 74 (95.9%) participants showed a positive difference. Symptom scores had the highest mean of 9.88 (SD 0.09) and lowest dispersion, whereas stressors showed greater variability (mean 3.68, SD 0.49). The estimated network showed predominant forward connections from psychosocial factors through emotion regulation and psychophysiological amplification indicators to gut-specific symptoms. The psychophysiological amplification module had the highest micro-to-macro flow efficiency and macro-level control metric. In the TVEM analysis, the full module-control and causal-emergence models explained 64.4% and 45.6% of the deviance, respectively.

In this longitudinal IBD patient cohort, daily monitoring identified a reproducible end-of-cycle stress comparison and an exploratory multiscale organization that links psychosocial, emotional, psychophysiological, and gut-specific symptom domains. The psychophysiological amplification module provides the most informative, comprehensive representation, although its organization varies depending on follow-up and disease status. These findings support the use of digital phenotypes to generate clinical evidence for the coordination of stress symptoms, tailored to individual situations.