[Introduction]
White matter hyperintensities (WMH) are considered manifestation of arteriosclerotic small vessel disease and WMH burden increases risk of ischemic stroke and cognitive decline. There are only a few evidences concerning the relationship between polyunsaturated fatty acids (PUFA) and WMH. The present study was designed to elucidate the association between WMH and PUFA profile including eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA) and arachidonic acid (AA) in patients with Alzheimer’s disease (AD).
[Methods]
The present study was based on 119 patients who were diagnosed as having a probable AD according to the NINCDS-ADRDA criteria. Their mean age was 78.3 years old. All subjects underwent neuropsychological evaluation including mini mental state exam (MMSE) and 1.5-Tesla MRI. Fasting blood samples were also collected for the PUFA measurements. We measured the ratio of serum EPA, DHA and AA concentration to the total PUFA concentration. The WMH were evaluated on T2-weight images and classified into periventricular hyperintensity (PVH) and deep white matter hyperintensity (DWMH). The severity of WMH was graded 5 categories. We investigated the relationship between WMH and PUFA profiles.
[Results]
The EPA ratio correlated negatively with both PVH (rs=-0.2036, p=0.0264) and DWMH grade (rs=-0.3155, p=0.0005). It remained still significant after adjustment for age, sex, statins use, antithrombotics use, mean blood pressure and presence of hypertension (standardized partial regression coefficient(β)=-0.2516, p=0.0122 for PVH, β=-0.3598, p=0.0001 for DWMH). Neither DHA nor AA ratio correlated with DWMH or PVH grade. The EPA ratio but not DHA or AA ratio correlated positively with total MMSE score (rs=0.2310, p=0.0115).
[Conclusions]
Our data revealed that the serum EPA was protective against WMH as well as cognitive decline in AD patients. Pathophysiology underlying WMH is complex and the possible mechanisms involved in the pathogenesis of WMH encompass incomplete brain ischemia, increased permeability of blood-brain barrier, and inflammation responses. The relationship between serum EPA and WMH can be partly explained by those anti-ischemic and anti-arteriosclerotic effects of EPA.
O4-09-04: Association of magnetic resonance imaging white matter lesions and cognitive decline in Alzheimer's disease
