Abstract
BACKGROUND: Irritable bowel syndrome (IBS) is one of the most common functional gastrointestinal disorders worldwide. However, its prevalence varies substantially across countries and regions, reflecting heterogeneity in diagnostic approaches, study populations, and cultural factors. In China, which has the world's largest population, the true burden of IBS remains uncertain. A comprehensive synthesis of prevalence estimates is needed to inform public health strategies and clinical care. METHODS: We systematically searched Chinese and international databases from inception to August 2025 to identify observational studies reporting IBS prevalence in Chinese populations. Eligible studies were assessed for quality and extracted independently by two reviewers. Random-effects meta-analyses using logit transformation and random-intercept logistic regression models were applied. Subgroup analyses by sex, age group, and IBS subtype were performed. Heterogeneity was quantified using the I (2) statistic and tau(2). RESULTS: A total of 65 studies (37 in Chinese and 28 in English) involving 197,764 participants and 23,341 IBS cases were included. Studies covered 23 provinces, with a concentration in Beijing, Shanghai, and Hubei, while no prevalence data were available for several regions including Hunan, Tianjin, Qinghai, and Xinjiang. The pooled prevalence of IBS in China was 11.0% (95% CI 9.0-13.4), with substantial heterogeneity (I (2) = 99.4%). Sex-stratified analyses showed prevalence estimates of 9.0% (95% CI 6.8-11.8) in men and 11.1% (95% CI 8.1-14.9) in women, with no significant difference between sexes (p = 0.29). By age, prevalence was highest in adults aged 18-59 years (12.0, 95% CI 9.6-14.9), lower in the elderly (8.2, 95% CI 5.1-13.0), and rare among children (<18 years: 1.4, 95% CI 0.2-11.4). Subtype analysis showed comparable prevalence across IBS-C (3.9%), IBS-D (4.3%), IBS-M (3.0%), and IBS-U (2.7%). CONCLUSION: This systematic review and meta-analysis reveals that IBS affects approximately 1 in 10 Chinese adults, with considerable variation across regions and subgroups. The findings highlight the need for nationally representative studies, standardized diagnostic criteria, and targeted health policies to address the burden of IBS in China.