APOE ε4 allele status in Korean dementia patients with severe white matter hyperintensities

Few studies have investigated the apolipoprotein E (APOE) ε4 allele status of dementia patients with severe white matter hyperintensities (WMH). In this study, we aimed to characterize the APOE epsivlon genotypes and clinical features of dementia patients with severe WMH. Four hundred and thirty nine patients with dementia and 152 subjects with normal cognition (NC) were recruited from multiple centers in Korea, known as the Clinical Research Center for Dementia of South Korea (CREDOS), since November 2005. The WMH were rated using the scale that had been developed by the CREDOS study. Dementia patients with minimal WMH were considered to have Alzheimer's disease (AD) without WMH (AD-WMH: 325), and those with severe WMH were considered to have Subcortical Ischemic Vascular Dementia (SIVD: 50) or AD with severe WMH (AD+WMH: 64). Comparisons of APOE ε4 allelic prevalence were performed using chi-square analysis. The APOE ε4 allele was more prevalent in those with AD than in those with SIVD and NC (p < 0.001). It was not more prevalent in those with SIVD than in those with NC (p = 0.169). APOE ε4 allele status in AD+WMH did not differ from that in AD-WMH (p = 0.625). The APOE ε4 allele was more prevalent in those with AD than in those with SIVD. APOE ε4 may not be associated with SIVD although it is one of the vascular risk factors.