4%. This result is comparable with the response rate (47.8%) for abdominal discomfort/pain in the recent largest, multinational Western study which used similar definition.15 IBS-specific quality of life has rarely been used as a primary end-point in the assessment of the effect of tegaserod on IBS, but IBS patients suffer from impaired health-related QOL as well as their IBS-related bowel symptoms.7-9 LB42708? Therefore, it is useful to evaluate the effect on QOL of patients with IBS by certain medication in clinical trials. However most clinical studies usually assessed symptomatic improvement or used only a summary score even if QOL was assessed. The pattern of bowel symptoms related to IBS seems to be similar across the country,29 but quality of life perceived by IBS patients varied depending on different cultural environments and countries rather than racial differences.

30,31 In the current study, the subscales with low scores (60-65) that can be considered as moderate to severe IBS were dysphoria, health worry, and food avoidance subscale and the score of health worry subscale was lowest. This result suggests that IBS patients suffer more from anxiety about their disease than impairment of social activity or relationship by bowel symptom. This poor QOL is an important factor that causes patients to consider their disease severe and self-reported severity only significantly correlated with QOL score, but not symptom score. For this reason, the assessment of IBS-QOL should be included as part of the therapeutic outcome in clinical trials that assess the efficacy of certain drugs on IBS patients.

The score of sexual function subscale was over 80 points and was not affected by tegaserod therapy in the present study, but there was a possibility that subjects did not report their actual sexual life. Koreans, especially females who make up the current study population, are reluctant to express sexual problems and this tendency was already observed in the previous study.20 There was no difference of baseline QOL between responders and nonresponders, but QOL was significantly improved in responder group. Interestingly, if symptom was aggravated after treatment, there was a tendency of decrease in QOL with greater score reduction in the subscales of interference with activities, social reaction, and relationship than other subscales.

This result suggests that as bowel symptoms become severe, Brefeldin_A the QOL about social activity is more impaired than the QOL about disease-related worry. Based on these results, it is suggested that we should try the bowel-directed treatment first, for the IBS-related anxiety and poor QOL and then if there is no improvement by this general management, additional treatment modality, such as antidepressant or psychiatric treatment, should be considered.