Relation of Serum Vitamin B12 and Red Cell Folate Levels to Age and Cognition in Healthy Individuals of Different Age Groups: A Cross Sectional Study

Background: Folate and vitamin B-12 have important role in cognition. There is scarcity of globally established cut-off levels to demarcate deficiency of either vitamin among different age groups. Aim: To determine age related differences in the levels of serum vitamin B-12, red blood cell folate and their association with cognition. Methods: This cross sectional study was conducted at Baqai Medical University and 240 healthy volunteers (<= 72 years) living in different areas of Karachi, fulfilling the inclusion-exclusion criteria, were included. The participants were grouped as: children (4-12 years); adults (13-55 years); elderly (56-72 years). Results: The mean serum vitamin B-12 and red blood cell folate levels for 4-12 years, 13-55 years, 56-72 years groups were 220.11 +/- 42.02pg/mL, 298.69 +/- 68.13pg/mL, and 197.33 +/- 11.65 pg/ml; 537.68 +/- 64.96ng/mL, 542.38 +/- 49.58ng/mL, and 536.44 +/- 52.05ng/mL, respectively. A significant strong positive correlation existed between serum vitamin B-12 levels and mini mental state examination scores (r = 0.770, p<.001). MMSE scores were significantly negatively correlated with age (r = -.717, p<.001). A significant strong positive correlation between modified child MMSE scores and age was observed (r = 0.784, p<.001). Percent deficiency values of vitamin B-12 was 41.3%, while 42.5% study population had marginal levels. Conclusion: Increased prevalence of vitamin B-12 deficiency and marginal status is a serious health issue. These findings should support dietary recommendations to enhance vitamin B-12 status and to improve cognition, especially for children and elderly individuals. Vitamin B-12 levels should be assessed in work up of cognitive decline and dementia.