title: [Vitamin B12 deficiency associated with high doses od metformin in older people diabetic].
abstract: BACKGROUND
  The aim of the study was to estimate if B12 deficiency is associated with the use of metformin in the elderly diabetics.
  
  
  METHODS
  Case-control study in diabetic OP. Cases (n = 137) were defined as elderly with B12 < 221 pmol/L and controls (n = 279) elderly with B12 > 221 pmol/L. Four categories of metformin use were defined: non-users, ≤850 mg/day, > 850 and < 2,550 mg/day and ≥2,550 mg/day. Metformin ≥2,550 mg/day was high doses considered. The crude OR for B12 deficiency and consumption of Metformin were calculated. Logistic regression models were developed to explore the association between B12 deficiency and metformin dose. The research protocol was approved by the Ethics Committee of INTA.
  
  
  RESULTS
  The age of cases and controls was (70.2 years vs 68.6 years (p < 0.05). The 62% were women in cases vs 74.9% in controls (p < 0.05). The 73% of cases and 76% of controls used metformin (p < 0.05) the average consumption of metformin was de 1,954.3 mg/day (SD: 1,063.2) in cases and 1,696.6 mg/day (SD: 1,074.4) in controls (p < 0.05). The use of 2,550 mg/day was observed in 29.2% of cases and 19.3% for controls (p < 0.05). It was observed that OP who consumed high doses of metformin had 1.9 times the risk of B12 deficiency (OR: 1.9; 95%CI: 1,08- 3,30).
  
  
  CONCLUSIONS
  These results show a strong association between high doses of metformin and low levels of vitamin B12 in diabetic elderly. This project was funded by FONIS SA11I2092.
authors: Unidad de Nutrición Pública, Instituto de Nutrición y Tecnología de los Alimentos (INTA). Universidad de Chile.. hsanchez@inta.uchile.cl.
authors: Hugo
authors: H
authors: Sánchez
authors: Unidad de Nutrición Pública, Instituto de Nutrición y Tecnología de los Alimentos (INTA). Universidad de Chile.. dominique.masferrer@gmail.com.
authors: Dominique
authors: D
authors: Masferrer
authors: Unidad de Nutrición Pública, Instituto de Nutrición y Tecnología de los Alimentos (INTA). Universidad de Chile.. llera@inta.uchile.cl.
authors: Lydia
authors: L
authors: Lera
authors: Corporación Municipal de Salud y Educación de Peñalolén. Chile.. earancibia@cormup.cl.
authors: Estrella
authors: E
authors: Arancibia
authors: Unidad de Nutrición Pública, Instituto de Nutrición y Tecnología de los Alimentos (INTA). Universidad de Chile.. bangel@inta.uchile.cl.
authors: Barbara
authors: B
authors: Angel
authors: Unidad de Nutrición Pública, Instituto de Nutrición y Tecnología de los Alimentos (INTA). Universidad de Chile.. calbala@uchile.cl.
authors: Cecilia
authors: C
authors: Albala
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D048909:Diabetes Complications / Q000139:chemically induced* / Q000378:metabolism; D003920:Diabetes Mellitus / Q000188:drug therapy*; D005260:Female; D006801:Humans; D007004:Hypoglycemic Agents / Q000009:adverse effects* / Q000627:therapeutic use; D008297:Male; D008687:Metformin / Q000009:adverse effects* / Q000627:therapeutic use; D008875:Middle Aged; D012737:Sex Factors; D014806:Vitamin B 12 Deficiency / Q000139:chemically induced* / Q000453:epidemiology
chemical_list: D007004:Hypoglycemic Agents; D008687:Metformin