title: Low serum cobalamin levels in a population study of 70- and 75-year-old subjects. Gastrointestinal causes and hematological effects.
abstract: We examined causes and hematological consequences of low serum cobalamin (vitamin B12) concentration in two representative population samples of 70-year-old (N = 293) and 75-year-old subjects (N = 486). Subjects with values below 130 pmol/liter (4.8% and 5.6%, respectively) were investigated with Schilling test, upper gastrointestinal endoscopy, determination of serum gastrin and group I pepsinogens, and bone marrow examination. Gastrointestinal abnormalities of etiologic significance were found in 26 of the 32 examined subjects: atrophy of the gastric body mucosa (N = 16, with pernicious anemia in six), partial gastrectomy (N = 6), and intestinal malabsorption (N = 4). Megaloblastic hematopoiesis was found in 10 individuals, four of whom had macrocytic anemia. Our results indicate that low serum cobalamin concentration in the elderly is usually a consequence of disease rather than of high age per se and that gastric mucosal atrophy is a major etiologic factor.
authors.affiliation: Department of Medicine, Ostra Hospital, Göteborg, Sweden.
authors.forename: H
authors.initials: H
authors.lastname: Nilsson-Ehle
authors.forename: S
authors.initials: S
authors.lastname: Landahl
authors.forename: G
authors.initials: G
authors.lastname: Lindstedt
authors.forename: L
authors.initials: L
authors.lastname: Netterblad
authors.forename: R
authors.initials: R
authors.lastname: Stockbruegger
authors.forename: J
authors.initials: J
authors.lastname: Westin
authors.forename: C
authors.initials: C
authors.lastname: Ahren
mesh_terms: D000368:Aged; D000375:Aging / Q000097:blood*; D000748:Anemia, Macrocytic / Q000097:blood*; D000749:Anemia, Megaloblastic / Q000097:blood* / Q000209:etiology; D000752:Anemia, Pernicious / Q000097:blood* / Q000209:etiology; D001856:Bone Marrow Examination; D004064:Digestive System / Q000473:pathology; D004724:Endoscopy; D005260:Female; D005755:Gastrins / Q000097:blood; D005767:Gastrointestinal Diseases / Q000097:blood* / Q000150:complications; D006801:Humans; D008297:Male; D010435:Pepsinogens / Q000097:blood; D012546:Schilling Test; D014805:Vitamin B 12 / Q000097:blood*
chemical_list: D005755:Gastrins; D010435:Pepsinogens; D014805:Vitamin B 12