Folate and vitamin B12 status in relation to cognitive impairment and anaemia in the setting of voluntary fortification in the UK

Concerns about risks for older people with vitamin B I, deficiency have delayed the introduction of mandatory folic acid fortification in the UK. We examined the risks of anaemia and cognitive impairment in older people with low B-12 and high folate status in the setting of voluntary fortification in the UK. Data were obtained from two cross-sectional studies (n 2403) conducted in Oxford city and Banbury in 1995 and 2003, respectively. Associations (OR and 95% CI) of cognitive impairment and of anaemia with low 131, Status (holotranscobalamin <45 pmol/l) with or without high folate status (defined either LIS Serum folate >30 nmol/l or >60 nmol/l) were estimated after adjustment for a-e. sex. smoking and study. Mean serum folate levels increased from 15.8 (SD 14.7) nmol/l in 1995 to 31.1 (SD 26.2) nmol/l in 2003. Serum folate levels were greater than 30 nmol/l in 9% and greater than 60 nmol/l in 5%. The association of cognitive impairment with low B12 status was unaffected by high v. low folate status (>30 nmol/l) (OR 1.50 (95% CI 0.91, 2.46) v. 1.45 (95% CI 1.19, 1.76)). respectively. The associations of cognitive impairment with low B-12 status were also Similar using the higher cut-off point of 60 nmol/l for folate Status ((OR 2.40: 95% CI 0.90. 0.71) V. (1.56; 95% CI 1.30, 1.88)). There was no evidence of modification by hi-h folate status of the associations of low B-12, with anaemia or cognitive impairment in the setting of voluntary fortification. but periodic surveys are needed to monitor fortification.