Associations Between Autoimmune Conditions and Gastric Cancer Risk Among Elderly Adults in the United States.

INTRODUCTION

Pernicious anemia (PA) is a risk factor for gastric cancer. Other autoimmune conditions may also contribute.

METHODS

In a case-control study, we evaluated 47 autoimmune conditions among 39,125 gastric cancers and 200,000 cancer-free controls.

RESULTS

Six conditions were associated with increased gastric cancer risk (range of adjusted odds ratios: 1.28-1.93, P < 0.05): PA, membranous nephropathy, primary biliary cirrhosis, pure red cell aplasia, primary sclerosing cholangitis, and Graves disease. PA was associated with 8 other autoimmune conditions (adjusted odds ratios: 1.57-4.54, P < 0.05).

DISCUSSION: Autoimmune conditions associated with gastric cancer or PA may reflect effects of autoimmune gastritis or other carcinogenic pathways.