Methods: This study is a cross-sectional study on 405 students from freshman to senior of high schools in Korea. All students were requested to fill in a self-reported questionnaire. IBS was diagnosed based on the Rome II criteria. For the evaluation of risk factors on the IBS, we surveyed dietary habit, lifestyle, past medical history, the Hospital Anxiety and Depression Scale (HADS) for anxiety and depression, the Brief Encounter Psychosocial Instrument for stress, and Menstrual Distress Questionnaire for PMS. Data were analyzed by chi-squared test and multiple logistic regressions.

Results: The prevalence of IBS was 25.7% in Korean high-school girls. There was significantly increased prevalence of IBS if subjects had higher stress levels (p < .001). Also, subjects who had severe anxiety had a 4.27-fold likehood of IBS (95% CI 1.09-16.71) compared with those who had normal anxiety. The risk of IBS prevalence was increased 13.21-fold (95% CI 1.40-124.91) in subjects who were mild depression, 17.08-fold (95% CI 1.83-159.11) in subjects who were moderate depression and 10.87-fold (95% CI 1.14-103.81) in subjects who were severe depression versus normal depression.

Conclusions: The prevalence of IBS in high school students from this study was higher compared with those reported in adults. This study shows that anxiety, depression and stress were significantly related to IBS. From our study, we found that there are multifaceted health aspects required to reduce symptoms, such as education and encouragement to change lifestyle for psychological distress.