SCFA Alterations in IBS Subtypes: Systematic Evidence and Future Prospects for Biomarker-Based Diagnosis in India
Year: 2026
Type: article
Study designs: Systematic Review, Meta-Analysis
Abstract: BackgroundIrritable bowel syndrome (IBS) is a chronic disorder of gut-brain interaction defined by recurrent abdominal pain associated with altered bowel habits, in the absence of structural or biochemical abnormalities.Diagnosis is based on symptom-based criteria, most widely the Rome IV framework, which emphasizes abdominal pain related to defecation and changes in stool frequency or form [1]. Globally, IBS affects approximately 7-10% of the population, though prevalence varies by geography, diagnostic criteria, and cultural reporting patterns [2].Subtypes include diarrhea-predominant (IBS-D), constipation-predominant (IBS-C), mixed (IBS-M), and unclassified (IBS-U), each with distinct symptom burden and therapeutic response profiles [1].Short-chain fatty acids (SCFAs), primarily acetate, propionate, and butyrate, are microbial metabolites generated by fermentation of dietary fiber.They exert diverse physiological effects, including modulation of intestinal motility, maintenance of epithelial barrier integrity, and regulation of immune responses [3].Altered SCFA profiles have been implicated in IBS pathogenesis, with propionate linked Irritable bowel syndrome (IBS) is a chronic disorder of gut-brain interaction characterized by abdominal pain and altered bowel habits.Short-chain fatty acids (SCFAs), microbial metabolites of dietary fiber, play key roles in gut physiology and have been implicated in IBS pathogenesis.Propionate, acetate, and butyrate are of particular interest as potential biomarkers for diagnosis and subtype differentiation.A systematic search of PubMed, Web of Science, and Embase identified studies reporting fecal SCFA concentrations in IBS patients versus healthy controls (HCs).Adult cohorts diagnosed by Rome criteria, casecontrol or randomized designs, and sufficient SCFA data for effect size calculation were included.Data were harmonized to mean ± SD and analyzed; pooled standardized mean differences (SMDs) with 95% confidence intervals (CI) were calculated, with subgroup analyses for IBS-D and IBS-C.Methodological quality was assessed using the Newcastle-Ottawa Scale (NOS).Eleven studies met inclusion criteria.Across all IBS cohorts, propionate was significantly elevated compared to HCs, while acetate and butyrate showed no differences.In IBS-D, propionate was consistently higher.In IBS-C, total SCFAs were significantly reduced, with negligible heterogeneity.Acetate, propionate, and butyrate remained non-significant, with moderate to substantial heterogeneity.NOS assessment indicated that most studies were of good quality, with one rated moderate.This meta-analysis highlights propionate elevation as a biomarker for IBS, particularly IBS-D, and reduced total SCFAs as a distinct metabolic signature in IBS-C.Variability in individual metabolites reflects dietary and methodological influences.The absence of Indian cohorts limits generalizability; future studies integrating SCFA profiling with microbiome analysis in Indian populations are needed to validate biomarker utility and support precision management of IBS.
Authors: Sanika Limaye, Prajkta Bhide, Anup Kale, Neha Bokey
Institution: MIT World Peace University
Language: English
Subfield: Gastroenterology
Field: Medicine
Domain: Health Sciences
Open Access status: bronze
OpenAlex ID: W7220700268