Apolipoprotein E polymorphism carriers exhibit objective cognitive deficits: a single center trial

ABSTRACT

Objective

To assess the correlation between objectively measured cognitive function and apolipoprotein E polymorphism within one geographic region.

Methods

61 patients, aged 55–90 years old, were enrolled in a memory clinic at the Beijing Luhe Hospital affiliated with Capital Medical University from September 2016 to September 2018. At this center, they were evaluated with neuropsychological scales to assess their memory and other aspects of cognitive function. Specific gene segments were extracted from venous blood by PCR amplification, and ApoE genotyping was carried out by chip hybridization.

Results

Among all patients, 0 had the genotype ε2/2, 7 had the genotype ε2/3, 0 had the genotype ε2/4, 40 had the genotype ε3/3, 12 had the genotype ε3/4, and 2 had the genotype ε4/4. The allele frequency ε2 accounted for 5.74%, ε3 accounted for 81.15% and ε4 accounted for 13.11%. The Mini-Mental State Examination (MMSE) scores of ε4 carriers (18.14 ± 0.39) were significantly lower than those of non-ε4 carriers (23.77 ± 6.29) (P < 0.05), and the Montreal Cognitive Assessment (MoCA) scores of ε4 carriers (14.36 ± 7.56) were also significantly lower than those of non-ε4 carriers (20.55 ± 8.08) (P < 0.05).

Conclusion

The rate of the ε3/3 homozygous genotype was the highest, followed by the rates of the ε3/4 and ε2/3 genotypes. The rates of the ε2/4, ε4/4, and ε2/2 genotypes were the lowest. Deficits in memory and other cognitive processes were significantly more pronounced in ε4 carriers than in non-ε4 carriers.

KEYWORDS:

• Memory clinic
• memory function
• cognitive function
• apolipoprotein E

Acknowledgments

We would like to thank professor Yuchuan Ding from Department of Neurosurgery at Wayne State University School of Medicine for the technical support he provided. This work was supported by grants from the Beijing Tongzhou District Science and Technology Planning Project (KJ2016CX037-16, KJ2018CX009-42).

Disclosure statement

No potential conflicts of interest were reported by the authors.

Additional information

Funding

Beijing Tongzhou District Science and Technology Planning Project (KJ2016CX037-16, KJ2018CX009-42).

Notes on contributors

Yanfang Zeng

Yanfang Zeng is a professor of Neurology at the Beijing Luhe Hospital, Capital Medical University (China). She has conducted in-depth research on cerebrovascular disease and dementia.

Xin Huang

Xin Huang is a doctor of Neurology at the Beijing Luhe Hospital, Capital Medical University (China). She has performed in-depth research on the subject of neurosis.

Kenneth Elkin

Kenneth Elkin is a medical student with the department of Neurosurgery at Wayne State University School of Medicine (USA). He has published on neuroprotection in the context of stroke.

Christopher Stone

Christopher Stone is a medical student with the department of Neurosurgery at Wayne State University School of Medicine (USA). He has published on neuroprotection in the context of stroke.

Gary B. Rajah

Yanfang Zeng is a professor of Neurology at the Beijing Luhe Hospital, Capital Medical University (China). She has conducted in-depth research on cerebrovascular disease and dementia.

Gary B. Rajah is an endovascular fellow with the department of Neurosurgery at the Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, New York, USA; he is also associated with the Gates Vascular Institute at Kaleida Health in Buffalo, New York, USA.

Longfei Guan

Longfei Guan is a research associate in the China-America Institute of Neuroscience at the Beijing Luhe Hospital, Capital Medical University (China).

Huishan Du

Huishan Du is a professor of Neurology at the Beijing Luhe Hospital, Capital Medical University (China). He has published on neuroprotection in the context of stroke.

Xiaokun Geng

Xiaokun Geng is a professor of Neurology at the Beijing Luhe Hospital, Capital Medical University (China). He has published on neuroprotection in the context of stroke.