SUMMARY: However, epidemiology data may be misleading due to several contentious diagnostic issues. The diagnostic conundrums are due to inherent complexity of the GEJ as a functional and pathological unit. Challenging diagnostic issues in Asia include the following: nonstandardized landmark of the GEJ, misclassification of Barrett esophagus, targeted versus nontargeted tissue sampling, histopathology disagreement and challenges in screening or surveillance of dysplastic BE and early GEJ cancer. The recent Asian-Pacific survey led by the Asian Barrett Consortium (ABC) has provided useful insights into these contentious issues. A key learning point from these diagnostic limitations is that the awareness of the disease and adherence to existing recommendations or guidelines are poor in the region. Key Messages: Standardization in diagnostic methodology is vital for accurate epidemiology data, and this can only come from better awareness and adherence through educational and international efforts. Last, surveillance strategy may need a paradigm shift from a purely diagnostic approach to a combined targeted surveillance and treatment approach using novel endoscopic techniques.
METHODOLOGY: Consecutive Asian adults with Rome III diagnosed common FGIDs (functional dyspepsia/FD, IBS and functional constipation/FC) and non-FGID controls were subjected to glucose breath testing, with hydrogen (H2) and methane (CH4) levels determined.
RESULTS: A total of 244 participants (FGIDs n = 186, controls n = 58, median age 45 years, males 36%, Malay ethnicity 76%) were recruited. FGIDs had a higher prevalence trend of SIBO compared to controls (16% FGIDs vs. 10% controls, p = 0.278) with 14% in FD, 18% in IBS and 17% in FC. Compared to controls, SIBO was associated with diarrhoea-predominant IBS (IBS-D) (24% vs. 10%, P = 0.050) but not with other types of FGIDs. IBS-D remained an independent predictor of SIBO (OR = 2.864, 95% CI 1.160-7.071, p = 0.023) but not PPI usage nor history of diabetes (both p > 0.050) at multivariate analysis. Compared to controls, SIBO in IBS-D was associated with an elevated H2 level (≥ 20 ppm from baseline) (18% vs. 3%, p = 0.017), but not CH4 levels (≥ 10 ppm) (9% vs. 7%, p = 0.493). In addition, no difference was found in the prevalence of methane-positive SIBO between chronic constipation (constipation-predominant IBS and FC) compared to controls (9% vs. 7%, P = 0.466).
CONCLUSION: SIBO is prevalent amongst multi-ethnic Asian adults with and without FGIDs. Amongst various FGIDs, only IBS-D is significantly associated with SIBO.