title: The prevalence of vitamin B(12) deficiency in patients with type 2 diabetes: a cross-sectional study.
abstract: OBJECTIVE
  The purpose of this study is to define the prevalence of vitamin B(12) 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 B(12) 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 B(12) levels measured. Patients with borderline B(12) levels also had methylmalonic acid and homocysteine levels drawn. Serum B(12) levels <100 pg/mL or serum B(12) levels of 100 to 350 pg/mL with elevation of serum methylmalonic acid >243 nmol/L or homocysteine >11.9 nmol/L defined B(12) deficiency. Descriptive statistics described frequency and means. chi(2) and student's t tests were used to analyze associations between categorical and continuous variables, respectively. Multivariate logistical regression identified covariates independently associated with B(12) deficiency.
  
  
  RESULTS
  Twenty-two percent (n = 44) of diabetic patients had metabolically confirmed B(12) deficiency. Patients on metformin had lower serum B(12) levels (425.99 pg/mL vs 527.49 pg/mL; P = .012) and were at increased risk for B(12) deficiency (P = .04), as defined by a serum B(12) level <350 pg/mL. Prevalence of B(12) 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 B(12) deficiency in the primary care type 2 diabetic population. Although further research needs to be performed to determine the clinical implications of our findings, B(12) deficiency should be considered in type 2 diabetic patients, especially those taking metformin. Furthermore, a daily multivitamin may protect against B(12) deficiency.
authors.affiliation: Department of Primary Care, Raymond W Bliss Army Health Center, Ft. Huachuca, AZ 85613, USA. matthew.pflipsen@us.army.mil
authors.forename: Matthew C
authors.initials: MC
authors.lastname: Pflipsen
authors.forename: Robert C
authors.initials: RC
authors.lastname: Oh
authors.forename: Aaron
authors.initials: A
authors.lastname: Saguil
authors.forename: Dean A
authors.initials: DA
authors.lastname: Seehusen
authors.forename: D
authors.initials: D
authors.lastname: Seaquist
authors.forename: Richard
authors.initials: R
authors.lastname: Topolski
mesh_terms: D000368:Aged; D015897:Comorbidity; D003430:Cross-Sectional Studies; D003924:Diabetes Mellitus, Type 2; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011320:Primary Health Care; D014806:Vitamin B 12 Deficiency / Q000175:diagnosis / Q000453:epidemiology*; D014861:Washington / Q000453:epidemiology