Long-term health outcomes of people without celiac disease avoiding gluten consumption: a 25-year prospective cohort study

BACKGROUND: Self-reported abdominal symptoms after consuming gluten-containing cereals in individuals without celiac disease (CeD) are common. The long-term outcomes of these individuals are unknown. METHODS: Seventy-six adults experiencing symptoms from gluten-containing cereals underwent exclusion of CeD and wheat allergy in 1995-1997 and were thus advised to revert to a normal gluten-containing diet. These individuals were invited to a comprehensive health examination, including measurement of CeD antibodies and symptoms and assessment of quality of life using the Gastrointestinal Symptom Rating Scale (GSRS) and Psychological General Well-Being Index (PGWB). Healthy individuals (n = 160) and untreated CeD patients (n = 128) served as controls. RESULTS: Altogether, 28 individuals participated, half of whom were still avoiding gluten-containing cereals. None had acquired a diagnosis of any gastrointestinal disease, and all had negative CeD serology. The entire study group presented with significantly higher GSRS total (participants 2.8, 95% confidence interval 2.5-3.1 vs. controls 1.8, 1.7-1.9; p < 0.001) and other sub-scores than healthy controls, and higher total (vs. patients 2.5, 2.3-2.6; p = 0.041) and constipation scores than untreated CeD patients. Additionally, the group had worse PGWB total (participants 92.1, 84.9-99.4 vs. controls 105.3, 102.5-108.7; p = 0.002) and anxiety, self-control, general health, and vitality sub-cores than healthy controls, as well as self-control, general health, and vitality scores than untreated CeD patients. Twelve participants fulfilled the criteria for irritable bowel syndrome. CONCLUSIONS: None of the participants had developed CeD or been diagnosed with gastrointestinal disease for 25 years. They reported more gastrointestinal symptoms and a poorer quality of life, even when compared to untreated CeD patients.