A Retrospective Study on Clinical Features of Autoimmune Gastritis: Impact of Age, Sex, and Autoimmune Thyroid Disease in China.

Abstract

Background/aims: Autoimmune gastritis (AIG) is an immune-mediated chronic atrophic gastritis. This study aimed to investigate the clinical characteristics of AIG patients, stratified by age, sex, and the presence/absence of autoimmune thyroid disease (AITD).

Methods: We reviewed the data of AIG patients treated at a large academic tertiary teaching hospital from January 2018 to October 2023. Patients were grouped according to age (≥60 years or younger), sex, and the presence/absence of AITD and the clinical characteristics of the groups were analyzed.

Results: This study included 183 AIG patients. Older patients (≥60 years) had higher rates of pernicious anemia (26.7% vs 11.8%) and intrinsic factor antibodies (36.8% vs 20.9%) than younger patients (<60 years). However, no significant differences were observed in the extent of gastric atrophy, sex ratio, or serum gastrin levels between the age groups. Female patients were more prone than males to exhibit enterochromaffin-like cell hyperplasia (69.4% vs 39.2%) and had a higher prevalence of iron deficiency anemia (IDA) (25.0% vs 0.0%, p=0.004). AIG patients with AITD were younger (50.9±12.0 years vs 58.0±11.5 years), were more likely to be females (p=0.023), and exhibited milder gastric body atrophy (p=0.009) than those without AITD.

Conclusions: AIG patients demonstrate age- and sex-related differences in clinical characteristics. Older patients are more likely to have intrinsic factor antibody positivity and pernicious anemia, while women are more prone to IDA. There is a high comorbidity rate between AITD and AIG, and patients with AITD-associated AIG are typically younger and tend to have milder gastric body atrophy.