The impact of diet and ethnicity on gut microbiota variation in irritable bowel syndrome: A multi‐center study

Abstract

Background and Aim:The gut microbiota in irritable bowel syndrome (IBS) is known to vary with diet. We aim to (i) analyze the gut microbiota composition of IBS patients from a multi-ethnic population and (ii) explore the impact of a low FODMAP diet on gastrointestinal symptoms and gut microbiota composition among IBS patients. Methods: A multi-center study of multi-ethnic Asian patients with IBS was conducted in two phases: (i) an initial cross-sectional gut microbiota composition study of IBS patients and healthy controls, followed by (ii) a single-arm 6-week dietary interventional study of the IBS patients alone, exploring clinical and gut microbiota changes. Results: A total of 34 adult IBS patients (IBS sub-types of IBS-D 44.1%, IBS-C 32.4%, and IBS-M 23.5%) and 15 healthy controls were recruited. A greater abundance of Parabacteroides species with lower levels of bacterial fermenters and short-chain fatty acids producers were found among IBS patients compared with healthy controls. Age and ethnicity were found to be associated with gut microbiota composition. Following a low FODMAP dietary intervention, symptom and quality of life improvement were observed in 24 (70.6%) IBS patients. Symptom improvement was associated with adherence to the low FODMAP diet (46.7% poor adherence vs 92.9% good adherence, P = 0.014), and gut microbiota patterns, particularly with a greater abundance of Bifidobacterium longum, Anaerotignum propionicum, and Blautia species post-intervention. Conclusion: Gut microbiota variation in multi-ethnic IBS patients may be related to dietary intake and may be helpful to identify patients who are likely to respond to a low FODMAP diet.

Can we predict who will respond to a low‐FODMAP diet in irritable bowel syndrome?

“…In a recent multicenter study amongst Asian IBS patients, Khoo et al . observed that poor adherence to the low‐FODMAP diet was prevalent amongst 51.7% of IBS subjects, despite regular monitoring by dietitians 7 . IBS patients with poorer adherence to a low FODMAP in this study had less symptom improvement (92.9% vs 46.7% symptom improvement between those with good vs poor adherence).…”

“…In a recent multicenter study amongst Asian IBS patients, Khoo et al observed that poor adherence to the low-FODMAP diet was prevalent amongst 51.7% of IBS subjects, despite regular monitoring by dietitians. 7 IBS patients with poorer adherence to a low FODMAP in this study had less symptom improvement (92.9% vs 46.7% symptom improvement between those with good vs poor adherence). However, even amongst IBS patients with a reported poor adherence, 46.7% had symptom improvement, suggesting that factors other than adherence may have influenced the dietary intervention response.…”

“…In the multicenter study by Khoo et al, investigators identified a higher baseline alpha diversity of gut microbiota, with a greater abundance of Bifidobacterium longum, Anaerotignum propionicum, and Blautia species at baseline amongst IBS patients who responded to a low-FODMAP diet, suggesting a difference in gut microbiota pattern between responders and non-responders to a low-FODMAP diet. 7 Similarly, a systematic review and meta-analysis exploring gut microbial changes after a low-FODMAP diet reported a distinct microbial pattern, with predominant reductions in bifidobacteria and actinobacteria organisms. 3 Additionally, investigators have explored measuring microbiota metabolites in both feces and urine as potential predictors of response to a low-FODMAP diet.…”

“…Several studies have explored factors, other than adherence, that may predict a response to a low‐FODMAP diet in adults in with IBS. In the multicenter study by Khoo et al ., investigators identified a higher baseline alpha diversity of gut microbiota, with a greater abundance of Bifidobacterium longum , Anaerotignum propionicum , and Blautia species at baseline amongst IBS patients who responded to a low‐FODMAP diet, suggesting a difference in gut microbiota pattern between responders and non‐responders to a low‐FODMAP diet 7 . Similarly, a systematic review and meta‐analysis exploring gut microbial changes after a low‐FODMAP diet reported a distinct microbial pattern, with predominant reductions in bifidobacteria and actinobacteria organisms 3 …”