The Association Between Vitamin C Levels and Mortality Due to Alzheimer’s Disease

by | Jul 23, 2024 | Alzheimer's Disease, Brain Health, Recent Articles, Vitamin C, Vitamins

Written by Harold Oster, MD. Results suggest an inverse association between vitamin C levels and mortality due to Alzheimer’s Disease.

aging coupleAlzheimer’s disease is a neurodegenerative disease that leads to loss of cognitive function, disability, and death. The etiology of Alzheimer’s Disease is incompletely understood, but it involves the accumulation of amyloid plaques and polymerized tau proteins in the brain, leading to oxidative damage, inflammation, and neuronal loss1. Vitamin C, which cannot be synthesized in humans, is found in various fruits and vegetables. It has antioxidant and anti-inflammatory properties2 and reduces amyloid plaque in a mouse model of Alzheimer’s Disease3.

Duke Appiah et al. studied the association between serum levels of vitamin C and Alzheimer’s Disease mortality in older adults. The authors analyzed data gathered between 1988 and 1994 by the National Health and Nutrition Examination Survey (NHANES), a population-based cross-sectional study conducted by the National Center for Health Statistics at the Centers for Disease Control and Prevention4. Participants in the study were at least sixty years old and free of cognitive dysfunction at baseline. Serum vitamin C levels were measured, and the participants were placed into tertiles based on the results. Cognitive function was assessed by standard clinical measures, including the Mini-Mental State Examination5 and the Weschler Adult Intelligence Scale6. Mortality data was gathered from the National Death Index, a database managed by the National Center for Health Statistics7. The participants were evaluated for possible covariables, including socioeconomic and lifestyle factors, diet, supplement use, medical history, and body mass index.

The authors noted the following:

  • Based on inclusion criteria, data from 4504 participants was used for the study.
  • The average age at baseline was 70.0 years.
  • 7% of the participants were men, and 86% reported non-Hispanic White race.
  • During a median follow-up of fifteen years, there were 153 deaths due to Alzheimer’s Disease.
  • After adjustment for covariables, participants in the highest serum vitamin C tertile had a lower risk of mortality due to Alzheimer’s Disease than those in the lowest tertile. (Hazard Ratio 1 of 0.44)
  • Participants with adequate levels of vitamin C, defined as a level equal to or greater than 0.5 mg/dL8, had a lower risk of Alzheimer’s Disease mortality compared to those with inadequate levels. (HR of 0.54)
  • 1% of participants had a vitamin C level above 2.3 mg/dL. They were more likely to have taken vitamin C supplements (2.0% vs. 0.4%) and had a higher risk of mortality due to Alzheimer’s Disease. (HR of 2.48)

Results suggest an inverse association between vitamin C levels and mortality due to Alzheimer’s Disease. Significantly elevated levels of vitamin C may be associated with an increased risk of Alzheimer’s Disease mortality. Limitations of the study include its observational design, the use of a single blood test for vitamin C levels, and possible residual confounding.

Source:  Appiah, Duke, Elyvine Ingabire-Gasana, Linda Appiah, and Jeanne Yang. “The Relation of Serum Vitamin C Concentrations with Alzheimer’s Disease Mortality in a National Cohort of Community-Dwelling Elderly Adults.” Nutrients 16, no. 11 (2024): 1672.

© 2024 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/
4.0/).

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Posted July 23, 2024.

Harold Oster, MD graduated from medical school in Miami, Florida in 1992 and moved to Minnesota in 2004. After more than 25 years of practicing Internal Medicine, he recently retired. Dr. Oster is especially interested in nutrition, weight management, and disease prevention. Visit his website at haroldoster.com.

References:

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