Prevalence and incidence of pernicious anemia. An evaluation for gastric screening.

To evaluate the feasibility of gastroscopic screening for gastric malignancy in patients with pernicious anemia, all individuals treated with vitamin B12 in a well-defined population were identified. Individuals treated for an uncertain diagnosis were submitted to supplementary examinations. Of all individuals treated with vitamin B12 41% had unequivocal pernicious anemia, 13% possible pernicious anemia, 26% vitamin B12 malabsorption other than pernicious anemia, and 20% no verified vitamin B12 deficiency. The maximum crude prevalence of pernicious anemia was 1.98 per mile and the crude maximum incidence 16.7 x 10(-5) x year-1. The estimated annual cost of endoscopic gastric screening at 3-year intervals in patients with pernicious anemia younger than 75 years of age would be SEK 15,000/100,000 inhabitants, a cost that to a great extent could be financed by a more adequate prescription of vitamin B12 treatment.