Prevalence Of Functional Gastrointestinal Disorders In Northern Chinese College And University Students

Background and aimsFunctional gastrointestinal disorders, including functional dyspepsia, irritable bowel syndrome and functional constipation are very common functional disease worldwide. They have become more prevalent with the global process of social and economic development. Functional gastrointestinal disorders are characterized by abdominal pain or discomfort with altered bowel habits, but without any organic damages to the intestine such as tumor or inflammation. They have a significant negative impact on health-related quality of life and result in high health care expenditures. Patients suffering from functional gastrointestinal disorders are badly bothered with both somatic and mental problems.The Rome Ⅲ criteria have been established in2006by the Rome Ⅲ Committee. Compared to the Rome Ⅲ criteria, Rome Ⅱ criteria have been used to examine a12-week period of time in the past12months, which is less than a continuous6-month period in the Rome Ⅲ criteria, thus expanding the scope of diagnosis.The prevalence of functional gastrointestinal disorders varied greatly among different investigations from different countries, which may be due to the differences such as varied study population from different countries and different diagnostic criteria or research methods used. Functional dyspepsia is divided into two subgroups according to the Rome Ⅲ criteria:epigastric pain syndrome and postprandial distress syndrome. The frequency of functional dyspepsia varied from8%-23%of the population. The prevalence of irritable bowel syndrome was15%-24%in the general population of Western countries, regardless of sex, age or ethnicity, with a male/female ratio of1:1.5. The distribution of three subtypes irritable bowel syndrome with constipation, irritable bowel syndrome with diarrhea and mixed irritable bowel syndrome was varied greatly. Research about epidemiology of functional constipation was rare. A survey showed the prevalence of FC in the general population of United States was14.7%.Until now, the prevalence of functional gastrointestinal disorders has been reported most frequently in general populations in Western countries, but not often in Chinese college and university students. This large school-based research aims to estimate the prevalence and associated factors involved in functional gastrointestinal disorders in Northern Chinese college and university students using the Rome III criteria.MethodsA total of5000students from Shandong University in China were asked in January-May2012to complete Chinese version of functional gastrointestinal disorders Rome III criteria questionnaires. The students have good consistency in age, diet, environment, family background and life habit. They are suitable for large population questionnaire survey. The students have high grade, good education background and better compliance. The data got from them are reliable.The students were randomly recruited from3areas of study (liberal arts, science, medicine), aged from17to25years old. The-study was approved by the Ethics Committee of Qilu Hospital of Shandong University, China.The20medical investigators and5keyboard operators were trained for this research before the survey process. Then, the experts on gastroenterology and epidemiology did the data selection and statistical analysis.The questionnaire was4-page long with83questions, including preface and introductions. The item types were single-choice and multiple-choice questions. It took about12minutes to finish the whole questionnaire. The questionnaire included the Chinese version Rome III questionnaire, hospital anxiety and depression scale, negative life events scale, and irritable bowel syndrome--quality of life questionnaire.Characteristics of students, prevalence of functional gastrointestinal disorders, scores of hospital anxiety and depression scale, negative life events scale and irritable bowel syndrome--quality of life questionnaire were measured and analyzed. The other underlying associated factors such as diet, alcohol and exercise were also involved.All eligible questionnaires were coded. Data analysis was performed using the SPSS12.0. Distributions of sex and lifestyle factors were analyzed by Pearson’s χ2or Fisher’s exact test. For each of the lifestyle factors and psychological measures, the choice or scores of participants were divided into3degrees. Analysis of variance was used to compare the anxiety and depression levels between groups. Possible risk factors were assessed by logistic regression analysis. Odds ratio (OR) with95%confidence interval (CI) was calculated. Data are presented as mean±SD. All calculated P-values were two-tailed and P<0.05was considered statistically significant.ResultsValid responses were obtained from4638participants, with a response rate of92.76%. Of the valid4638participants,2215(47.8%) were males and2423(52.2%) were females, with a mean age of20.64±1.428years and20.88±1.572years, respectively. The average college level of the students was2.53±0.162. Of the valid4638participants,3461(74.6%) were natives of Shandong Province.The prevalence of functional dyspepsia, irritable bowel syndrome and functional constipation in college and university students of Northern China worked out to be9.25%,8.34%and5.45%respectively. They were much more frequent in female students.In subtype group analysis,429were functional dyspepsia, including164(38.2%) had epigastric pain syndrome and265(61.8%) had postprandial distress syndrome. And387were irritable bowel syndrome, with150(38.8%) had IBS-C,189(48.8%) had IBS-D,48(12.4%) had IBS-M.The factors of anxiety (OR1.07;95%CI0.99to1.16, P=0.002,0.05) and depression (OR0.55;95%CI0.15to1.05, P=0.045,0.05) indicated a high risk of causing irritable bowel syndrome, and were independently associated with irritable bowel syndrome. The mean anxiety score were6.23±4.564(IBS-C),6.65±4.934(IBS-D), and6.47±4.360(IBS-M). The mean depression score were6.76±3.946(IBS-C),6.69±4.362(IBS-D), and6.96±4.658(IBS-M).The mean score of irritable bowel syndrome patients was74.2±4.242on the irritable bowel syndrome--quality of life questionnaire. No difference was found in measures related to the intake of dairy product (P=0.796), cold dishes (P=0.774) and alcohol (P=0.750) between the patients and normal groups, but significant differences were observed in exercise level, indicating that a low exercise level (P=0.007) is a high risk factor for irritable bowel syndrome.ConclusionsFunctional gastrointestinal disorders, including functional dyspepsia, irritable bowel syndrome and functional constipation are common in Chinese college and university students, with the prevalence of9.25%,8.34%and5.45%. Postprandial distress syndrome and irritable bowel syndrome with diarrhea are the most common subtype of functional dyspepsia and irritable bowel syndrome. Psychological disorders such as anxiety and depression are independently associated with irritable bowel syndrome. And low exercise level provides significant risk factors for irritable bowel syndrome patients.SignificationFunctional gastrointestinal disorders, including functional dyspepsia, irritable bowel syndrome and functional constipation are very common worldwide. They have become more prevalent with the global process of social and economic development. They have a significant negative impact on health-related quality of life and result in high health care expenditures. Patients suffering from functional gastrointestinal disorders were badly bothered with both somatic and mental problems.Until now, most research in our country was based on Rome criteria in diagnosing functional gastrointestinal disorders. Although the Rome III criteria have been established in2006by the Rome III Committee, there were little data about Rome III criteria on functional gastrointestinal disorders, especially the research on specific population.Furthermore, many investigators consider that the Rome Ⅱ criteria have their advantages in rapid diagnosis and have better maneuverability in clinical practice. That is why they prefer the Rome Ⅱ criteria and the popularization of Rome Ⅲ criteria is much slower.This is the first large school-based investigation on the epidemiology of functional gastrointestinal disorders in Northern Chinese college and university students using the Rome Ⅲ criteria.Our research has high quality in trial design, questionnaire selection, standardization, professional analysis, validation, and so on. It provides many important materials for further clinical trial, systematic analysis and population survey. It can also be imitated by other investigators.The questionnaire used in this program was a comprehensive Chinese version of functional gastrointestinal disorders Rome Ⅲ criteria. It will be very useful in the future research.