Format

Send to

Choose Destination
Am J Clin Nutr. 2015 Jul;102(1):9-19. doi: 10.3945/ajcn.114.097394. Epub 2015 May 20.

Is achlorhydria a cause of iron deficiency anemia?

Author information

1
Department of Internal Medicine, Baylor University Medical Center, Dallas, TX.
2
Department of Internal Medicine, Baylor University Medical Center, Dallas, TX johnfo@baylorhealth.edu.

Abstract

We re-evaluated the old hypothesis that gastritis-induced achlorhydria is a cause of iron deficiency anemia (IDA) in humans. First, we analyzed the currently available research on the association between achlorhydria and IDA. When gastric acid secretion was measured after maximal stimulation, the frequency of achlorhydria (or severe hypochlorhydria) was 44% in patients with idiopathic IDA and 1.8% in healthy controls. In some patients with pernicious anemia, presumed achlorhydria preceded the development of IDA in time. However, we found no credible evidence that IDA caused gastritis or that IDA preceded the development of achlorhydria. Thus, correlational results favor achlorhydria as the causal factor in the association between achlorhydria and IDA. Second, we sought to determine whether gastritis and achlorhydria cause negative iron balance. When biosynthetic methods were used to isotopically label iron in food, achlorhydric patients were found to have severe malabsorption of nonheme iron, which persisted after the development of IDA. In 1 study, achlorhydria reduced the normal increase in heme-iron absorption from hemoglobin in response to iron deficiency. After an injection of isotopic iron into normal men, the physiologic loss of iron from the body was found to be 1 mg/d. Patients with chronic gastritis had excess fecal loss of isotopically tagged plasma iron. Calculations based on these results indicate that the absorption of iron from a typical Western diet by achlorhydric patients would be less than physiologic iron losses, creating a negative iron balance that could not be overcome by the adaptive increase in duodenal iron absorptive capacity that occurs in response to iron deficiency. The combination of results from these correlational and pathophysiologic studies supports the hypothesis that gastritis-induced achlorhydria can be an independent cause of IDA.

KEYWORDS:

achlorhydria; chronic atrophic gastritis; iron deficiency anemia; iron malabsorption; pernicious anemia

Comment in

PMID:
25994564
DOI:
10.3945/ajcn.114.097394
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Silverchair Information Systems
Loading ...
Support Center