Is Environmental Enteric Dysfunction Reversible in Adults? A 7‐Year Observational Follow‐up Study of Histological and Biomarker Outcomes in Urban Bangladesh

Background and Aims Environmental Enteric Dysfunction (EED) is a subclinical condition of the small intestine linked to chronic inflammation, impaired absorption, which results in undernutrition. While extensively studied in children, its persistence and reversibility in adults remain poorly characterised. Methods This 7‐year follow‐up study re‐evaluated adults with histology‐confirmed EED originally identified in the Bangladesh Environmental Enteric Dysfunction study. Of 60 adults diagnosed at baseline (2016–2018), 39 were successfully re‐contacted in 2023. Follow‐up assessments included anthropometry, household and hygiene conditions, and stool biomarker measurements for myeloperoxidase (MPO), neopterin (NEO), and alpha‐1 antitrypsin (AAT). EED reversal was defined as achieving a body mass index (BMI) ≥ 18.5 kg/m² along with improvement in at least two of three biomarkers (≥ 0.5 SD reduction from baseline). Associations between environmental changes and reversal were examined using Fisher's exact test and Firth's logistic regression. A p ‐value of < 0.05 was considered significant. Results After 7 years, 28.2% ( n / N = 11/39) of participants met criteria for EED reversal. Agreement between the two definitions was high (92.3%, p > 0.99). Median BMI increased from 17.2 to 18.5 kg/m², with marked declines in log‐transformed NEO (7.2 to 4.2) and MPO (6.6 to 6.3). Favourable transitions in sanitation (uOR: 6.36; 95% CI: 1.11–36.44), overcrowding (uOR: 4.61; 95% CI: 1.01–20.99), and upward social class (uOR: 8.61; 95% CI: 1.75–42.35) were significantly associated with EED status reversal. Neopterin showed the highest degree of improvement (94.9%), followed by MPO (87.2%) and AAT (56.4%). Conclusion This study presents rare long‐term evidence suggesting that EED in adults is at least partially reversible. Recovery was more commonly observed among individuals who experienced improvements in sanitation, reduced household crowding, and improved social class. These findings highlight the potential benefits of integrated interventions, sustained improvements in sanitation and living conditions to promote long‐term intestinal health in adults residing in resource‐limited settings.