Causal association between plant foods intake and Alzheimer's disease: a Mendelian randomization study

ABSTRACT

Background

Alzheimer's disease (AD) is a degenerative disease of the nervous system. Observational studies have found an association between plant food intake and AD. However, it is unclear whether this association is influenced by confounding factors. We aimed to explore the causal relationship between plant-based diet and the risk of AD using two-sample Mendelian randomization.

Materials and Methods

We obtained datasets of exposure from the IEU Open GWAS project, including dried fruit intake, fresh fruit intake, raw vegetable intake, cooked vegetable intake, and cereal intake. The summary data for AD were obtained from a large GWAS meta-analysis containing 71,880 cases and 383,378 controls.

Results

Increased intake of dried fruits was associated with a reduced risk of AD (IVW: OR = 0.88, 95CI = 0.82–0.95). No causal association was found between the intake of other foods and AD.

Conclusion

This MR study suggests that genetically predicted increased intake of dried fruits is a causal protective factor for AD.

KEYWORDS:

• Diet
• dried fruit
• foods‌
• Alzheimer's disease
• Mendelian randomization
• single nucleotide polymorphisms‌
• genome-wide association study
• causal association

Acknowledgments

We thank the following institutions/projects for making the summary data publicly available, including the IEU open GWAS project, and UKB Biobank.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Author contributions

Conceptualization, Xinmin Deng.; Methods, Xinmin Deng and Jingyi Zhu.; Formal Analysis, Xinmin Deng.; Investigation, Wen Chang.; Resources, Xiaofeng Lv and Rui Lai.; Data organization, Jingyi Zhu.; Writing-original draft preparation, Xinmin Deng and Jingyi Zhu.; Writing-review and editing, Xinmin Deng and Jingtao Liang.; Visualization, Wen Chang.; Supervision, Jingtao Liang.; Project management, Xinmin Deng and Jingtao Liang. All authors have read and agreed to the published version of the manuscript.

Informed consent statement and ethics statement

Ethical approval and participant agreement are not necessary because each of the original GWAS has already been approved.

Data availability statement

The original contributions presented in the study are included in the article/Supplementary Material, further inquiries can be directed to the corresponding authors.

Additional information

Funding

The author(s) reported there is no funding associated with the work featured in this article.

Notes on contributors

Xinmin Deng

Xinmin Deng is a graduate student at Chengdu University of Traditional Chinese Medicine. His major research fields include diagnosis, prevention and treatment of neurodegenerative diseases.

Jingyi Zhu

Jingyi Zhu is a graduate student at Chengdu University of Traditional Chinese Medicine. His major research fields include diagnosis, prevention and treatment of neurodegenerative diseases.

Jingtao Liang

Jingtao Liang is the chief physician of the department of neurology, Hospital of Chengdu University of Traditional Chinese Medicine. His main research fields include diagnosis, prevention and treatment of various central and peripheral nervous system diseases.

Wen Chang

Wen Chang is a graduate student at Chengdu University of Traditional Chinese Medicine. His major research fields include diagnosis, prevention and treatment of neurodegenerative diseases.

Xiaofeng Lv

Xiaofeng Lv is a graduate student at Chengdu University of Traditional Chinese Medicine. His major research fields include clinical research on acupuncture and moxibustion treatment of various chronic diseases.

Rui Lai

Rui Lai is a graduate student at Chengdu University of Traditional Chinese Medicine. His major research fields include clinical research on acupuncture and moxibustion treatment of various chronic diseases.