A Three‑Stage Autonomic Biofeedback Program Improves IBS Symptoms and Quality of Life

Background. Irritable bowel syndrome (IBS) is a prevalent disorder of gut–brain interaction with substantial quality‑of‑life (QoL) burden and heterogeneous mechanisms, motivating individualized, mechanism‑informed care. Methods. We conducted a single‑arm, prospective pre–post study of 120 enrolled adults with IBS offered a 12‑week, three‑stage, therapist‑delivered program integrating psychoeducation; autonomic self‑regulation with heart‑rate variability (HRV), skin conductance level (SCL), and peripheral temperature biofeedback; targeted interoceptive provocation paired with real‑time autonomic stabilization; and psychosocial trigger work with relapse‑prevention planning. Pelvic‑floor/anorectal sEMG biofeedback was not included. The primary outcome was IBS‑SSS total (0–500); secondary outcomes were IBS‑QoL total (sum of 34 items; each 1–5 transformed to 0-100) and eight QoL subscales. Analyses used paired tests with effect sizes and FDR correction for subscales; exploratory correlations linked ΔIBS‑SSS to ΔIBS‑QoL. Results. Of 120 enrolled, 84 (70.0%) completed all 12 sessions and both assessments (drop‑out 30.0%). In the complete‑case cohort (n=84), IBS‑SSS decreased from 307.7 ± 100.2 to 137.0 ± 83.1 (Δ=−170.7; 95% CI −186.7 to −154.7; dz=2.32; p≈2.6×10⁻³⁵; Wilcoxon p≈1.71×10⁻¹⁵). The IBS‑QoL mean paired increase was +45.17 points (95% CI +41.89 to +48.46; dz = 2.98; t(83) = 27.35, p = 2.80×10⁻⁴³; Wilcoxon p = 1.71×10⁻¹⁵). All eight domains improved substantially and significantly after the program (q ≪ 0.001 across all subscales). The largest average gains were in Health Worry and Food Avoidance, followed by Social Reaction and Sexual function; Body Image improved the least. Symptom improvement correlated moderately with QoL gains (Pearson r≈−0.342). There was no evidence of sex moderation (ΔSeverity×Sex: b = +0.0422, SE = 0.0584, t = 0.72, p = 0.472), indicating similar severity–QoL coupling in women and men. The ΔSeverity×Age interaction was small and non-significant (b = +0.0030 per year, SE = 0.0018, t = 1.69, p = 0.0943); the point estimate corresponds to a very slight attenuation of the slope with older age (about 3 QoL points less per 100-point IBS-SSS decrease for someone 10 years above the sample mean), but this did not reach conventional thresholds. Interpretation. A structured, autonomic‑anchored complex therapy was feasible and associated with large, clinically meaningful improvements in IBS symptoms and QoL across multiple domains – particularly health worry, food avoidance, and social reaction –that are not uniformly addressed by diet or drugs alone. Causal inference is limited by the uncontrolled design and 30% attrition; a randomized controlled trial is warranted to test the incremental value of autonomic biofeedback within integrated IBS care and to evaluate durability and mechanistic biomarkers alongside patient‑reported outcomes. Keywords: Irritable Bowel Syndrome; Disorders of Gut–Brain Interaction; Heart Rate Variability (HRV) Biofeedback; Electrodermal Activity (Skin Conductance); Peripheral Temperature Biofeedback; Autonomic Nervous System Regulation; Interoceptive Exposure; Resonance Frequency; Health‑Related Quality of Life (IBS‑QoL); IBS Symptom Severity Scale (IBS‑SSS).