Association between dietary vitamin E intake and cognitive decline among old American: National Health and Nutrition Examination Survey

Eur Geriatr Med. 2023 Oct;14(5):1027-1036. doi: 10.1007/s41999-023-00814-w. Epub 2023 Aug 24.

Abstract

Purpose: Numerous studies have reported that vitamin E plays a key role in nervous system development and neurotransmitter production. This study aimed to investigate changes in vitamin E intake in older adults with low cognitive performance using NHANES.

Methods: In this cross-sectional study, we examined a sample of 2255 American adults aged 60 and over between 2011 and 2014. We collected dietary data by averaging two recalls for dietary use to determine vitamin E intake. We assessed cognitive function using five tests and analyzed the association between these variables using a multivariate logistic regression model.

Results: A total of 2255 participants aged ≥ 60 years from the National Health and Nutrition Examination Survey (NHANES) for the 2011-2014 cycle were included in the analysis. Vitamin E intake was negatively associated with cognitive function. In the Z test, with each 1 mg/day increase in dietary intake of vitamin E, there was a 6% decrease in the correlation with cognitive impairment (OR = 0.94, 95% CI 0.91-0.97) in the fully fitted model (OR = 0.94, 95% CI 0.91-0.97). These findings remained consistent when analyzing the exposure as a categorical variable. In comparison to Q1, Q4 showed a 53% reduction in the incidence of cognitive impairment in the Z test (OR = 0.47, 95% CI 0.33-0.67).No significant statistical interaction between the variables was found.

Conclusion: An increased dietary intake of vitamin E has been associated with decreased cognitive impairment in individuals over 60 years old. The dose-response curve showed an L-shaped association between dietary vitamin E intake and cognitive decline in US adults, with an inflection point of approximately 9.296 mg/day.

Keywords: Association; Cognition; Generalized additive model; Subgroup analysis; Vitamin E intake.