Positive serum antigliadin antibodies without celiac disease in the elderly population: does it matter?

Abstract
Objective. Antigliadin antibodies (AGA) show good sensitivity but low specificity for celiac disease and can also be found in healthy individuals. However, data suggest that AGA positivity might be related to distinct disease entities such as allergy and gluten ataxia. Our aim here is to explore the clinical relevance of positive AGA in the elderly population. Material and methods. Serum IgA- and IgG-class AGA and IgA-class tissue transglutaminase antibodies (tTGA) were determined in 2815 individuals aged 52-74 years. Equal numbers of AGA- and tTGA-negative participants of similar age and gender, but without known celiac disease, were randomly selected as controls. Information on clinical history was obtained from hospital records in all groups. Results. Altogether 381 persons were positive for IgA/IgG-class AGA; 38 (14%) of them were also positive for tTGA. Out of the biopsied subjects, 34 (100%) in the AGA+ tTGA+ group and five (9%) in AGA+ tTGA- group had celiac disease. Rheumatoid arthritis and depression were found significantly more often in AGA- positives than controls. The significance remained even when tTGA-positive and known celiac disease cases were excluded. No statistical differences were found in the occurrence of neurological diseases, diabetes, allergic and cardiovascular diseases or malignancies. Conclusions. Although AGA positivity is of clinical relevance only in a subset of elderly people, it seems to be related to rheumatoid arthritis and depression, both conditions linked to celiac disease. Further studies are needed to reveal the mechanisms underlying this. The poor specificity of AGA for celiac disease was here once more in evidence.