Inheritance of the ApoE epsilon 4 allele increases the rate of brain atrophy in dementia patients

We investigated the influence of the apolipoprotein (ApoE) epsilon 4 allele on the rate of brain atrophy in patients with clinical dementia and in sub jects at risk for dementia. Eighty-one subjects, consecutively referred to a memory clinic due to symptoms of dementia, went through a comprehensive e xamination, including cerebral magnetic resonance imaging. After an initial investigation these subjects were divided into one of six diagnostic group s; Alzheimer's disease (AD, n = 23), objective cognitive impairment (OCI, n = 27), subjective cognitive impairment (SCI, n = 17), vascular dementia (V aD), frontotemporal dementia (FTD) and unspecified dementia (USD). The last three groups were joined into one diagnostic group designated 'other demen tia' (OD, altogether n = 14). In order to study the progression of cognitiv e impairment as well as the rate of atrophy in different brain regions all subjects were reinvestigated after an average period of 16 monhts. Interest was focused on investigating if those subjects with one or two epsilon 4 a lleles differed in either dementia progression or rate of brain atrophy com pared to those without the epsilon 4 allele. We found that the ApoE epsilon 4 carriers had a statistically significantly larger increase in ventricula r volume as compared with the ApoE epsilon 4 noncarriers. In all diagnostic groups the ApoE epsilon 4 carriers showed a greater rate of ventricular vo lume increase, as compared to the noncarriers. However, th is difference wa s statistically significant on ly for the OD subjects. No statistical signi ficant changes over lime were seen for whole brain volume or volume of the temporal lobes and the medial temporal lobes. The diagnostic groups differe d in dementia progression with the AD subjects having the most pronounced r eduction in MMSE scores as compared to subjects at risk for AD (OCI and SCI subjects). The presence of ApoE epsilon 4 allele did not influence the cha nge in MMSE in any of the diagnostic groups.