Document Type : Scientific Research

Authors

• Hossein Haji Ali Akbari ¹
• Abbas Mokhtari ²

¹ M.Sc. Student in Clinical Psychology, Department of Clinical Psychology, Na.C., Islamic Azad University, Najafabad, Iran

² Assistant Professor, Department of Health Psychology, Na.C., Islamic Azad University, Najafabad, Iran.

Abstract

Objective: The present study aimed to develop a structural equation model to predict life satisfaction based on the severity of irritable bowel syndrome (IBS) symptoms and perceived stress, with the mediating roles of pain catastrophizing, anxiety sensitivity, emotion regulation, and cognitive flexibility in patients with IBS. Irritable bowel syndrome is considered one of the most prevalent functional gastrointestinal disorders and is characterized by persistent alterations in bowel habits, such as diarrhea, constipation, or a combination of both, accompanied by abdominal pain and discomfort. A defining feature of this disorder is the absence of identifiable structural or biochemical abnormalities in routine clinical examinations and laboratory tests. In other words, despite the substantial impact of these symptoms on patients’ quality of life, no clear organic cause has been established. In recent years, numerous studies have examined the influence of psychological factors on the experience and exacerbation of IBS symptoms. Findings from this body of research indicate a close association between IBS and variables such as perceived stress, pain catastrophizing, anxiety sensitivity, cognitive flexibility, and emotion regulation. Patients with IBS commonly experience high levels of psychological distress, anxiety, and mood disturbances in addition to physical pain, which can substantially diminish their overall life satisfaction. Method: The present study adopted a descriptive–correlational design and was conducted using structural equation modeling (SEM) with a path analysis framework. The target population included all individuals who were diagnosed with irritable bowel syndrome (IBS) by a gastroenterologist, based on endoscopic and colonoscopic examinations, and who referred to gastroenterology clinics and medical centers in Isfahan, Iran, during 2025. Participants were recruited using a convenience sampling method. Although there is no universally accepted guideline for determining sample size in SEM studies, methodological recommendations generally suggest a minimum of 200 participants to ensure adequate statistical power and model stability. Accordingly, an initial sample of 225 patients with IBS, aged 20 to 75 years, was recruited. After screening the data, 25 cases were excluded due to incomplete questionnaire responses. Consequently, data from 200 participants were retained for the final analyses. Data were collected using a battery of standardized self-report instruments, including the IBS Symptom Severity Questionnaire (Solati, 2008), the Perceived Stress Scale (Cohen et al., 1983), the Satisfaction with Life Scale (Diener et al., 1985), the Pain Catastrophizing Questionnaire (Rahmati et al., 2017), the Anxiety Sensitivity Index (Reiss & Peterson, 1986), the Emotion Regulation Questionnaire (Gross & John, 2003), and the Cognitive Flexibility Inventory (Dennis & Vander Wal, 2010). Data analyses were conducted using Pearson’s correlation coefficients and structural equation modeling with path analysis. All statistical analyses were performed using SPSS (Version 26) and AMOS (Version 24). Results: The results of the path analysis indicated that IBS symptom severity had a significant positive direct effect on pain catastrophizing (β=.25, p<.01) and anxiety sensitivity (β=.49, p<.01). However, the direct effect of IBS symptom severity on life satisfaction was not statistically significant  (β = .03, p = .555). In addition, perceived stress demonstrated a significant positive direct effect on anxiety sensitivity (β= .18, p<.01), pain catastrophizing (β=.18, p<.01), and ife satisfaction (β = .21, p <.01). Thedirct effect of pain catastrophizing on emotion regulation was not significant (β=.02, p=.727). I contrast, emotion regulation had a significant positive direct effect on life satisfaction (β=.24, p<.01). Furthermore, anxiety sensitivity did not have a significant direct effect on cognitive flexibility (β=−.11, p=.106). However, cognitive flexibility showed a significant positive direct effect on life satisfaction (β=.23, p<.01). Overall, the findings supported the hypothesized structural model, confirming the proposed relationships among the study variables.Conclusion: The present study aimed to develop a structural equation model to predict life satisfaction based on the severity of irritable bowel syndrome (IBS) symptoms and perceived stress, with pain catastrophizing, anxiety sensitivity, emotion regulation, and cognitive flexibility as mediating variables. The results indicated that the proposed model demonstrated good fit. Findings showed that the severity of IBS symptoms directly increased pain catastrophizing and anxiety sensitivity but had no direct effect on life satisfaction. This suggests that the mere presence of physical symptoms does not necessarily reduce patients’ life satisfaction; rather, such reductions occur through intermediary psychological processes. According to cognitive pain processing and emotion regulation theories, individuals who focus on the negative aspects of physical symptoms and appraise them as threatening experience more intense pain and lower quality of life. Similar results have been reported by Carter et al. (2017), indicating that individuals with functional gastrointestinal disorders who experience high levels of stress and anxiety report lower quality of life. Considering the study’s findings and the significant role of mediating variables, it is essential to develop workshops and programs aimed at enhancing adaptive coping skills, such as problem-solving, mindfulness, and acceptance, for this population.

Keywords

• Anxiety sensitivity
• emotion regulation
• irritable bowel syndrome
• life satisfaction
• perceived stress

Main Subjects

• A