The association of serum ionized calcium and vitamin D with adult cognitive performance.
BACKGROUND
High serum calcium levels have been associated with cognitive decline in older adults. These associations have not been studied in younger adults. The possible association of vitamin D with cognitive function, independent of calcium, is unknown.


METHODS
A cross-sectional study of associations of serum ionized calcium and 25-hydroxyvitamin D levels with cognitive function in younger adults (20-59 years) and older adults (60-90 years) was conducted using data from the US third National Health and Nutrition Examination Survey (NHANES III).


RESULTS
Neither serum ionized calcium nor 25-hydroxyvitamin D was associated with cognitive function in either age group. For example, the confounder-adjusted mean difference in reaction time in young adults was 0.00 (95% confidence interval = -0.07 to 0.06) per 1 SD calcium.


CONCLUSIONS
Our results do not support an important role for calcium or vitamin D in cognitive performance in adults.
Tolppanen
Anna-Maija
AM
MRC Centre for Causal Analyses in Translational Epidemiology, School of Social and Community Medicine, University of Bristol, Bristol, United Kingdom.
Williams
Dylan M
DM
Lawlor
Debbie A
DA
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002118:Calcium / Q000097:blood*; D002136:Calcium, Dietary; D003071:Cognition / Q000502:physiology*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009749:Nutrition Surveys; D014481:United States; D014807:Vitamin D / Q000097:blood*; D055815:Young Adult
D002136:Calcium, Dietary; D014807:Vitamin D; D002118:Calcium