Association between proton pump inhibitor use and anemia: a retrospective cohort study

Dig Dis Sci. 2011 Aug;56(8):2349-53. doi: 10.1007/s10620-011-1589-y. Epub 2011 Feb 12.

Abstract

Background: Proton pump inhibitors (PPIs) are widely prescribed to treat gastrointestinal diseases. However, concerns have been raised regarding their long-term use. Gastric acid suppression may decrease iron absorption, and it remains uncertain whether iron-deficiency anemia may result from chronic PPI therapy.

Aims: We aimed to explore the association between chronic PPI use and iron-deficiency anemia.

Methods: We conducted a retrospective cohort study of adult patients in an academic outpatient setting who received PPI therapy for at least 1 year between January 1, 2004 and January 1, 2006. We compared the change in hematologic indices among patients receiving PPI therapy for at least 1 year with matched controls.

Results: Of the 98 patients on chronic PPI therapy who met inclusion criteria, 35% had no documented indication for such therapy. At baseline, demographics and hematologic indices were similar between PPI-users and controls. Among patients on PPI therapy, all hematologic indices decreased from baseline, including hemoglobin (-0.19 g/dL, P=0.03), hematocrit (-0.63%, P=0.02), and mean corpuscular volume (-0.49 fL, P=0.05). PPI users had significant decreases in mean hemoglobin and hematocrit (P<0.01 for both) compared with matched controls. After adjustment for confounders, including rates of esophagogastroduodenoscopy, colonoscopy and remote cancer status, the odds ratio of decreasing hemoglobin by 1.0 g/dL while on chronic PPI therapy was 5.03 (95% CI, 1.71-14.78, P<0.01), while the odds ratio of decreasing hematocrit by 3% was 5.46 (95% CI, 1.67-17.85, P<0.01).

Conclusions: Among adult patients receiving chronic PPI therapy, there is a significant decrease in hematologic indices from baseline.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Anemia, Iron-Deficiency / chemically induced*
  • Erythrocyte Indices / drug effects
  • Female
  • Gastric Acid / metabolism
  • Hematocrit
  • Humans
  • Male
  • Middle Aged
  • Proton Pump Inhibitors / adverse effects*
  • Proton Pump Inhibitors / therapeutic use
  • Retrospective Studies
  • Young Adult

Substances

  • Proton Pump Inhibitors