TY - JOUR

T1 - Vitamin-B 12-mangel im höheren lebensalter - Pathogenetische aspekte eines weit verbeiteten problems

AU - Ströhle, A.

AU - Wolters, M.

AU - Hahn, Andreas

PY - 2004/3

Y1 - 2004/3

N2 - Vitamin B 12 deficiency is a common problem in the elderly. If a serum cobalamin level of about 150 pmol/L (200 pg/mL) is considered normal, 10-15% of the elderly are deficient. Today, however, levels of 220-258 pmol/L (300-350 pg/mL) are regarded as desirable in the elderly, or more sensitive markers such as the blood concentration of homocysteine or methylmalonic acid are used. Then the prevalence of cobalamin deficiency increases to 43%. In the elderly, this is predominantly caused by atrophic gastritis type B. Atrophic gastritis results in insufficient gastric acid and pepsinogen secretion, leading to poor intestinal absorption of the cobalamin protein complexes from food. This applies to about 20-50% of the elderly. Reduced acid secretion, furthermore, leads to an alkalinisation of the small intestine which may result in bacterial overgrowth and a further decrease of the bioavailability of the vitamin. In addition, many drugs such as proton pump inhibitors or H 2 receptor antagonists inhibit the intestinal absorption of vitamin B 12. A moderately reduced vitamin B 12 level is already associated with vascular disease and neurocognitive disorders such as depression and impaired cognitive performance. A poor vitamin B 12 status, furthermore, is assumed to be involved in the development and progression of dementia (e.g. Alzheimer's disease). This applies especially to cases in which the folic acid status is reduced as well. In view of a possibly inadequate supply, the cobalamin status of elderly persons (≥60 years) should be regularly monitored and a general vitamin B 12 supplementation (≥50 μg/d) be considered.

AB - Vitamin B 12 deficiency is a common problem in the elderly. If a serum cobalamin level of about 150 pmol/L (200 pg/mL) is considered normal, 10-15% of the elderly are deficient. Today, however, levels of 220-258 pmol/L (300-350 pg/mL) are regarded as desirable in the elderly, or more sensitive markers such as the blood concentration of homocysteine or methylmalonic acid are used. Then the prevalence of cobalamin deficiency increases to 43%. In the elderly, this is predominantly caused by atrophic gastritis type B. Atrophic gastritis results in insufficient gastric acid and pepsinogen secretion, leading to poor intestinal absorption of the cobalamin protein complexes from food. This applies to about 20-50% of the elderly. Reduced acid secretion, furthermore, leads to an alkalinisation of the small intestine which may result in bacterial overgrowth and a further decrease of the bioavailability of the vitamin. In addition, many drugs such as proton pump inhibitors or H 2 receptor antagonists inhibit the intestinal absorption of vitamin B 12. A moderately reduced vitamin B 12 level is already associated with vascular disease and neurocognitive disorders such as depression and impaired cognitive performance. A poor vitamin B 12 status, furthermore, is assumed to be involved in the development and progression of dementia (e.g. Alzheimer's disease). This applies especially to cases in which the folic acid status is reduced as well. In view of a possibly inadequate supply, the cobalamin status of elderly persons (≥60 years) should be regularly monitored and a general vitamin B 12 supplementation (≥50 μg/d) be considered.

KW - Atrophic gastritis

KW - Elderly

KW - Homocysteine

KW - Methylmalonic acid

KW - Neurodegenerative diseases

KW - Vitamin B deficiency

KW - Vitamin B supplements

UR - http://www.scopus.com/inward/record.url?scp=2942707767&partnerID=8YFLogxK

M3 - Übersichtsarbeit

AN - SCOPUS:2942707767

VL - 51

SP - 90-95+82

JO - ERNAHRUNGS UMSCHAU

JF - ERNAHRUNGS UMSCHAU

SN - 0174-0008

IS - 3

ER -