Role of nerve growth factor on cognitive impairment in Alzheimer's disease patients carrying apolipoprotein E ε4

Abstract Background Apolipoprotein E (APOE) ε4 and neurotrophic factors are related to Alzheimer’s disease (AD). This study aimed to investigate roles of neurotrophic factors on cognition in AD patients carrying APOE ε4. Methods 173 AD patients were divided into the APOE ε4 carrier and the APOE ε4 non-carrier groups. Demographics, cognition, and neurotrophic factors in CSF were compared between two groups. Correlations among APOE ε4, neurotrophic factors, and cognition were analysed. Results 55 AD patients carried APOE ε4. Global cognition and multiple domains were impaired in the APOE ε4 carrier group. Nerve growth factor (NGF) in CSF from the APOE ε4 carrier group were decreased. NGF correlated with global cognition and multiple domains. NGF mediated associations between APOE ε4 and language, attention/executive function. All P < 0.05. Conclusion In AD, APOE ε4 is associated with cognitive impairment and patients carrying APOE ε4 have decreased NGF in CSF. Declined NGF correlates with compromised cognition. NGF mediates APOE ε4-related cognitive impairment.