title: Long-term use of proton pump inhibitors and vitamin B12 status in elderly individuals.
abstract: BACKGROUND
  Some studies have shown that short-term use of proton pump inhibitors decreases the absorption of vitamin B12, but the results of studies into long-term proton pump inhibitor use and vitamin B12 deficiency are inconsistent.
  
  
  OBJECTIVE
  To investigate whether long-term proton pump inhibitor use is associated with an abnormal vitamin B12 status in elderly individuals.
  
  
  METHODS
  One hundred and twenty-five long-term (>3, years) proton pump inhibitor users aged 65, years and above were recruited from general practices. Their 125 partners (who did not use proton pump inhibitors) served as the reference group. Vitamin B12 status was determined by serum levels of vitamin B12 and homocysteine, and mean corpuscular volume.
  
  
  RESULTS
  No differences in mean vitamin B12 levels were observed between the long-term proton pump inhibitor users and their partners [345 (s.d. 126), pm vs. 339 (s.d. 133), pm, P, =, 0.73], even after adjustment for age, gender, Helicobacter pylori status and C-reactive protein levels (P, =, 0.87). Four proton pump inhibitor users and three partners had vitamin B12 levels <150, pm (3% vs. 2%, P, =, 1.00). No differences between the groups were observed in homocysteine levels and mean corpuscular volume.
  
  
  CONCLUSIONS
  No association between long-term proton pump inhibitor use and vitamin B12 status was observed. Regular testing for low vitamin B12 levels in elderly patients on long-term treatment with proton pump inhibitors is therefore not recommended.
authors.affiliation: Department of Public Health and Primary Care, Leiden University Medical Centre, Leiden, The Netherlands. w.p.j.den_elzen@lumc.nl
authors.forename: W P J
authors.initials: WP
authors.lastname: den Elzen
authors.forename: Y
authors.initials: Y
authors.lastname: Groeneveld
authors.forename: W
authors.initials: W
authors.lastname: de Ruijter
authors.forename: J H M
authors.initials: JH
authors.lastname: Souverijn
authors.forename: S
authors.initials: S
authors.lastname: le Cessie
authors.forename: W J J
authors.initials: WJ
authors.lastname: Assendelft
authors.forename: J
authors.initials: J
authors.lastname: Gussekloo
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008297:Male; D009426:Netherlands; D054328:Proton Pump Inhibitors; D017494:Proton Pumps / Q000009:adverse effects; D013272:Stomach Diseases / Q000188:drug therapy; D013997:Time Factors; D014805:Vitamin B 12 / Q000097:blood; D014806:Vitamin B 12 Deficiency / Q000139:chemically induced*
chemical_list: D054328:Proton Pump Inhibitors; D017494:Proton Pumps; D014805:Vitamin B 12