Distinct psychophysiological biomarkers and risk stratification models for irritable bowel syndrome with constipation (IBS-C) and diarrhea (IBS-D)

Irritable bowel syndrome (IBS) is a prevalent disorder of gut-brain interaction (DGBI) with a complex, multifactorial pathogenesis. Emerging evidence underscores the significant role of psychosocial factors; however, comprehensive models integrating multidimensional psychophysiological biomarkers to predict IBS subtypes often lack validation in this highly heterogeneous population. To evaluate the value of a psychophysiological multimodal approach in identifying predictive signatures for irritable bowel syndrome with constipation (IBS-C) and diarrhea (IBS-D). In this cross-sectional study, 80 IBS-C patients, 80 IBS-D patients, and 80 healthy controls were included. Assessments included eye-tracking (cognitive-emotional interaction), heart rate variability (autonomic function), psychological scales (SCL-90, SCSQ, EPQ), and the Pittsburgh Sleep Quality Index (PSQI). Multivariable logistic regression and ROC analyses were utilized to identify predictors and evaluate internal model performance. Shared predictive factors for both subtypes included the SCL-90 hostility factor, EPQ neuroticism, negative coping, and global PSQI score (all P < 0.05). IBS-C was specifically associated with hostility and neuroticism, whereas IBS-D was distinctively predicted by prolonged prosaccade latency, reduced HRV medium-frequency power, and a lack of positive coping. The models demonstrated strong internal discrimination, with AUCs up to 0.983 for IBS-C and 0.967 for IBS-D. Psychosocial factors and sleep disturbances are robust shared predictive risk factors for IBS-C and IBS-D. Furthermore, multimodal profiling reveals subtype-specific predictive signatures: prominent emotional reactivity in IBS-C, and altered sensory-autonomic integration in IBS-D. These findings underscore the associative heterogeneity of IBS and highlight the potential utility of psychophysiologically targeted interventions.