TY - JOUR
T1 - High folic acid or folate combined with low vitamin B-12 status
T2 - Potential but inconsistent association with cognitive function in a nationally representative cross-sectional sample of US older adults participating in the NHANES
AU - Bailey, Regan L.
AU - Jun, Shinyoung
AU - Murphy, Lisa
AU - Green, Ralph
AU - Gahche, Jaime J.
AU - Dwyer, Johanna T.
AU - Potischman, Nancy
AU - McCabe, George P.
AU - Miller, Joshua William
N1 - Publisher Copyright:
© 2020 Published by Oxford University Press on behalf of the American Society for Nutrition 2020.
Copyright:
Copyright 2021 Elsevier B.V., All rights reserved.
PY - 2020/12/1
Y1 - 2020/12/1
N2 - Background: Potential safety concerns relative to impaired cognitive function may exist when high folic acid exposures are combined with low vitamin B-12 status. Objectives: We aimed to examine the relation of the coexistence of high folate and low vitamin B-12 status with cognitive function, utilizing various definitions of "high"folate status. Methods: Cross-sectional data from older adults (≥60 y; n = 2420) from the 2011-2014 NHANES were analyzed. High folate status was defined as unmetabolized serum folic acid (UMFA) > 1 nmol/L or serum total folate > 74.1 nmol/L, and low vitamin B-12 status as methylmalonic acid > 271 nmol/L or serum vitamin B-12 < 150 pmol/L. Logistic regression models estimated ORs of scoring low on 1 of 4 cognitive tests: the Digit Symbol Substitution Test (DSST), the Consortium to Establish a Registry for Alzheimer's Disease Delayed Recall (CERAD-DR) and Word Learning tests, and the Animal Fluency test (AF). Results: A significant interaction was observed relative to scoring low on the DSST (<34; UMFA; P-interaction = 0.0071) and AF (serum folate; P-interaction = 0.0078) for low vitamin B-12 and high folate status. Among those with low vitamin B-12, high UMFA or high serum total folate was associated with higher risk of scoring low on the DSST (OR: 2.16; 95% CI: 1.05, 4.47) and the AF (OR: 1.93; 95% CI: 1.08, 3.45). Among those with "normal"vitamin B-12, higher UMFA or serum total folate was protective on the CERAD-DR. In noninteraction models, when high folate and normal vitamin B-12 status was the reference group, low vitamin B-12 combined with high UMFA was associated with greater risk based on the DSST (<34, OR: 2.87; 95% CI: 1.85, 4.45; <40, OR: 2.22; 95% CI: 1.31, 3.75) and AF (OR: 1.97; 95% CI: 1.30, 2.97); but low vitamin B-12 and lower UMFA (OR: 1.69; 95% CI: 1.16, 2.47) was also significantly associated for DSST < 40 risk. Conclusions: Low vitamin B-12 was associated with cognitive impairment both independently and in an interactive manner with high folate for certain cognitive performance tests among older adults.
AB - Background: Potential safety concerns relative to impaired cognitive function may exist when high folic acid exposures are combined with low vitamin B-12 status. Objectives: We aimed to examine the relation of the coexistence of high folate and low vitamin B-12 status with cognitive function, utilizing various definitions of "high"folate status. Methods: Cross-sectional data from older adults (≥60 y; n = 2420) from the 2011-2014 NHANES were analyzed. High folate status was defined as unmetabolized serum folic acid (UMFA) > 1 nmol/L or serum total folate > 74.1 nmol/L, and low vitamin B-12 status as methylmalonic acid > 271 nmol/L or serum vitamin B-12 < 150 pmol/L. Logistic regression models estimated ORs of scoring low on 1 of 4 cognitive tests: the Digit Symbol Substitution Test (DSST), the Consortium to Establish a Registry for Alzheimer's Disease Delayed Recall (CERAD-DR) and Word Learning tests, and the Animal Fluency test (AF). Results: A significant interaction was observed relative to scoring low on the DSST (<34; UMFA; P-interaction = 0.0071) and AF (serum folate; P-interaction = 0.0078) for low vitamin B-12 and high folate status. Among those with low vitamin B-12, high UMFA or high serum total folate was associated with higher risk of scoring low on the DSST (OR: 2.16; 95% CI: 1.05, 4.47) and the AF (OR: 1.93; 95% CI: 1.08, 3.45). Among those with "normal"vitamin B-12, higher UMFA or serum total folate was protective on the CERAD-DR. In noninteraction models, when high folate and normal vitamin B-12 status was the reference group, low vitamin B-12 combined with high UMFA was associated with greater risk based on the DSST (<34, OR: 2.87; 95% CI: 1.85, 4.45; <40, OR: 2.22; 95% CI: 1.31, 3.75) and AF (OR: 1.97; 95% CI: 1.30, 2.97); but low vitamin B-12 and lower UMFA (OR: 1.69; 95% CI: 1.16, 2.47) was also significantly associated for DSST < 40 risk. Conclusions: Low vitamin B-12 was associated with cognitive impairment both independently and in an interactive manner with high folate for certain cognitive performance tests among older adults.
KW - cognitive function
KW - folate
KW - interaction
KW - NHANES
KW - older adults
KW - unmetabolized folic acid
KW - vitamin B-12
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U2 - 10.1093/ajcn/nqaa239
DO - 10.1093/ajcn/nqaa239
M3 - Article
C2 - 32860400
AN - SCOPUS:85098456764
VL - 112
SP - 1547
EP - 1557
JO - American Journal of Clinical Nutrition
JF - American Journal of Clinical Nutrition
SN - 0002-9165
IS - 6
ER -