The prevalence of vitamin B12 deficiency in patients with type 2 diabetes: A cross-sectional study

Matthew C. Pflipsen, Robert C. Oh, Aaron Saguil, Dean A. Seehusen, Richard Topolski

Research output: Contribution to journalArticlepeer-review

123 Scopus citations


Purpose: The purpose of this study is to define the prevalence of vitamin B12 deficiency in a type 2 diabetic population within a primary care practice. Metformin use and advanced age are associated with vitamin B 12 deficiency and often present in type 2 diabetic patients, yet the prevalence of vitamin B12 deficiency in the diabetic population is unknown. Methods: We conducted a cross-sectional study of 203 outpatient type 2 diabetic patients at a large military primary care clinic. Patients completed a survey and had B12 levels measured. Patients with borderline B 12 levels also had methylmalonic acid and homocysteine levels drawn. Serum B12 levels <100 pg/mL or serum B12 levels of 100 to 350 pg/mL with elevation of serum methylmalonic acid >243 nmol/L or homocysteine >11.9 nmol/L defined B12 deficiency. Descriptive statistics described frequency and means. χ2 and student's t tests were used to analyze associations between categorical and continuous variables, respectively. Multivariate logistical regression identified covariates independently associated with B12 deficiency. Results: Twenty-two percent (n = 44) of diabetic patients had metabolically confirmed B12 deficiency. Patients on metformin had lower serum B12 levels (425.99 pg/mL vs 527.49 pg/mL; P = .012) and were at increased risk for B12 deficiency (P = .04), as defined by a serum B12 level <350 pg/mL. Prevalence of B12 deficiency was significantly lower for patients using a multivitamin (odds ratio, 0.31; 95% CI, 0.15-0.63). Conclusions: Our results found a 22% prevalence of metabolically confirmed B12 deficiency in the primary care type 2 diabetic population. Although further research needs to be performed to determine the clinical implications of our findings, B12 deficiency should be considered in type 2 diabetic patients, especially those taking metformin. Furthermore, a daily multivitamin may protect against B12 deficiency.

Original languageEnglish (US)
Pages (from-to)528-534
Number of pages7
JournalJournal of the American Board of Family Medicine
Issue number5
StatePublished - Sep 2009

ASJC Scopus subject areas

  • Public Health, Environmental and Occupational Health
  • Family Practice


Dive into the research topics of 'The prevalence of vitamin B12 deficiency in patients with type 2 diabetes: A cross-sectional study'. Together they form a unique fingerprint.

Cite this