APOE ε4 genotype, lifestyle profiles, and cognitive function among Chinese oldest old

Abstract

Background APOE ε4 is the single most important genetic risk factor for cognitive impairment and Alzheimer disease. While its interaction with lifestyle profile on cognition has been controversial and a recent study indicated that healthy lifestyle profiles only showed its benefits among APOE ε4 non‐carriers among those elderly aged over 65 years old. Accordingly, we examined the association between the APOE genotype and cognitive impairment and its interaction with lifestyle profiles among Chinese oldest old (aged over 80 years old). Method APOE ε4 is the single most important genetic risk factor for cognitive impairment and Alzheimer disease. While its interaction with lifestyle profile on cognition has been controversial and a recent study indicated that healthy lifestyle profiles only showed its benefits among APOE ε4 non‐carriers among those elderly aged over 65 years old. Accordingly, we examined the association between the APOE genotype and cognitive impairment and its interaction with lifestyle profiles among Chinese oldest old (aged over 80 years old). Result Among the 6,160 participants, 57.6% were women and 17.5% were APOE ε4 carriers, with a mean age of 90.1 (SD 7.2) years. The mean MMSE score was 23.3 (SD: 0.4) and 18.2% of the participants had cognitive impairment at baseline. Carrying APOE e4 allele was associated with 22% higher odds (95% CI: 1.02‐1.46) of cognitive impairment. Compared with those with unhealthy lifestyle score, participants with healthy lifestyle score were associated with a 38% (95% CI: 23% ‐ 50%) lower odds of cognitive impairment. No significant interaction between APOE genotype and lifestyle profiles was observed. The association between lifestyle profiles and cognitive function did not vary by APOE genotype. Conclusion APOE genotype and lifestyle profiles were associated with cognitive function among Chinese oldest old, respectively and healthier lifestyle is associated with lower odds of cognitive impairment regardless of APOE genotype.