Significance of Rome II-defined functional constipation in Taiwan and comparison with constipation-predominant irritable bowel syndrome C.-L. LU, F.-Y. CHANG, C.-Y. CHEN, J.-C. LUO & S.-D. LEE Division of Gastroenterology, Taipei Veterans General Hospital, School of Medicine National Yang-Ming University, Taipei, Taiwan Correspondence to: Dr F.-Y. Chang, Division of Gastroenterology, Taipei Veterans General Hospital, No. 201, Sec. 2, Shih-Pai Rd, Taipei 11217, Taiwan. E-mail: changfy@vghtpe.gov.tw Publication data Submitted 3 March 2006 First decision 23 March 2006 Resubmitted 27 March 2006 Accepted 31 March 2006 SUMMARY Background The epidemiology and impact of functional constipation on Asians remain unclear. Aim To determine the prevalence of functional constipation, its social/med- ical impact, and its distinction from constipation-predominant irritable bowel syndrome (C-IBS) in Taiwan. Methods A Rome II questionnaire was administered to an apparently healthy adult Chinese population (n ¼ 2865). Results The prevalence of functional constipation was 8.5% and it was 2.7% for C-IBS. The functional constipation subjects were predominantly female and had excessive gastrointestinal-related doctor visits, absenteeism and sleep disturbance compared with controls (P < 0.01). Among functional constipation subjects, approximately 40% were ‘consulters’ with exces- sive doctor consultations, absenteeism and sleep disturbance. Female gender, the presence of sleep difficulty and higher constipation symptom scores were predictive of their consultation behaviour (P < 0.05). No dif- ferences existed in demographic variables, doctor consultations and absenteeism between 172 functional constipation and 54 C-IBS subjects. However, the C-IBS subjects experienced more severe constipation symptoms and sleep disturbance than functional constipation subjects. Conclusions Functional constipation in Taiwan is comparable with that in other countries. The clinical presentation of constipation-predominant irritable bowel syndrome differ somewhat from that of functional constipation. Aliment Pharmacol Ther 24, 429–438 Alimentary Pharmacology & Therapeutics ª 2006 The Authors 429 Journal compilation ª 2006 Blackwell Publishing Ltd doi:10.1111/j.1365-2036.2006.02949.x