Comparing the Effectiveness of Schema Therapy and Mindfulness-Based Cognitive Therapy on Sleep Quality in Patients with Irritable Bowel Syndrome

Abstract

The present study aimed to compare the effectiveness of schema therapy and mindfulness-based cognitive therapy (MBCT) on sleep quality in patients with irritable bowel syndrome (IBS) in Isfahan. This study employed a quasi-experimental design with pretest, posttest, three-month follow-up, and a control group. The statistical population consisted of patients diagnosed with IBS who had referred to medical and treatment centers in Isfahan in 2025. Forty-five eligible participants were selected through convenience sampling and randomly assigned to three groups: schema therapy (n = 15), mindfulness-based cognitive therapy (n = 15), and control (n = 15). The schema therapy group received twelve 90-minute sessions based on Young’s schema therapy protocol, while the MBCT group participated in eight 90-minute sessions based on Kabat-Zinn’s mindfulness-based cognitive program. The control group received no psychological intervention. Sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI). Data were analyzed using mixed repeated-measures analysis of variance and Bonferroni post hoc comparisons. The multivariate mixed repeated-measures analysis revealed a significant group effect on the combined sleep quality components (Wilks’ Lambda = .007, F = 12.40, p = .001, η² = .915). Significant group and Time × Group interaction effects were observed across all sleep quality components, including subjective sleep quality, sleep latency, sleep duration, sleep efficiency, sleep disturbances, use of sleep medication, and daytime dysfunction (p < .05). Bonferroni post hoc analyses indicated that both schema therapy and MBCT produced significantly greater improvements in sleep quality than the control group at posttest and follow-up assessments (p < .01). However, no statistically significant differences were found between schema therapy and MBCT in any sleep quality outcome (p > .05). Both schema therapy and mindfulness-based cognitive therapy were effective in improving sleep quality among patients with IBS, and these therapeutic gains were maintained at the three-month follow-up. Although both interventions significantly outperformed the control condition, neither demonstrated superiority over the other, suggesting that schema therapy and MBCT are comparably effective psychological approaches for enhancing sleep quality in this population.