Impact of blood type, functional polymorphism (T-1676C) of the COX-1 gene promoter and clinical factors on the development of peptic ulcer during cardiovascular prophylaxis with low-dose aspirin.

AIMS: To investigate the impact of blood type, functional polymorphism (T-1676C) of the COX-1 gene promoter, and clinical factors on the development of peptic ulcer during cardiovascular prophylaxis with low-dose aspirin. METHODS: In a case-control study including 111 low-dose aspirin users with peptic ulcers and 109 controls (asymptomatic aspirin users), the polymorphism (T-1676C) of the COX-1 gene promoter was genotyped, and blood type, H pylori status, and clinical factors were assessed. RESULTS: Univariate analysis showed no significant differences in genotype frequencies of the COX-1 gene at position -1676 between the peptic ulcer group and control group. Multivariate analysis revealed that blood type O, advanced age, history of peptic ulcer, and concomitant use of NSAID were the independent risk factors for the development of peptic ulcer with the odds ratios of the 2.1, 3.1, 27.6, and 2.9, respectively. CONCLUSION: The C-1676T polymorphism in the COX-1 gene promoter is not a risk factor for ulcer formation during treatment with low-dose aspirin. Blood type O, advanced age, history of peptic ulcer, and concomitant use of NSAID are of independent significance in predicting peptic ulcer development during treatment with low-dose aspirin.