Wearable‐Based Monitoring of Autonomic and Gastrointestinal Function in Disorders of Gut‐Brain Interaction: A Systematic Review and Meta‐Analyses

BACKGROUND: Autonomic nervous system (ANS) activity is implicated in the pathogenesis of disorders of gut-brain interaction (DGBI). Technological advances enable more accurate investigation of ANS function. AIM: This study aimed to evaluate the clinical utility of wearable devices in monitoring autonomic and gastrointestinal (GI) function in DGBI. METHODS: A systematic search identified studies in adults with DGBI using wearables to assess heart rate variability (HRV), sleep, skin conductance, or gastric myoelectric activity as clinical readouts for ANS and GI function. The review provides an overview of available devices, while the meta-analysis evaluates consistency in detecting differences between DGBI and healthy controls (HCs). Associations between autonomic function and GI symptom severity were explored. Methodological quality was assessed using the Cochrane risk of bias tool and ROBINS-I. Meta-analyses used random-effects models with standardized mean differences (SMDs). RESULTS: Thirty-six studies (3 RCTs, 33 observational) involving 3986 DGBI patients were included (HRV: n = 16, sleep: n = 7, gastric myoelectric activity: n = 14, skin conductance: n = 0). Meta-analyses showed lower Root Mean Square of Successive Differences (SMD = -0.503, SE 0.189, 95% CI [-0.873, -0.132]) and percentage of successive RR intervals differing by > 50 ms (SMD = -0.430, SE 0.176, 95% CI [-0.775, -0.085]), reflecting HRV alterations in DGBI versus HCs. No consistent differences were found for other metrics, except normal gastric slow waves (SMD = -0.722, SE 0.216, 95% CI [-1.146, -0.298]). Heterogeneous ANS-symptom associations precluded definitive conclusions. CONCLUSIONS: Wearables show potential for detecting altered ANS and GI function in DGBI, particularly via HRV. Result variability highlights need for further research to confirm accuracy and clinical utility.